Childhood and  Adult Obesity--a new approach provides the world with a challenge

                                                Thomas T. Samaras

                                                Reventropy Associates

                                                San Diego, CA

Many health authorities subscribe to the belief that abundant nutrition; high birth weight, rapid growth and taller height characterize healthy children. Unfortunately, this approach appears to have produced the current epidemics in obesity and chronic diseases.

Obesity and nutrition experts such as, Barry Popkin, Colin Campbell, Hugh Trowell and Denis Burkitt, have noted that the Western food system developed over the last 150 years has been devastating to our health. These experts attribute our health problems to excessive animal protein and processed foods. For example, the combination of modern nutrition, greater height and higher body mass index have led to undesirable higher levels of cholesterol, glucose, insulin, C-reactive protein, insulin-like growth factor-1, and lower levels of sex hormone binding globulin, adiponectin, and high density lipoprotein. Undesirable levels of these factors are also related to cardiovascular disease (CVD), type 2 diabetes, and many cancers.

Many researchers attribute our increased life expectancy over the last 150 years to our food system. However, increased life expectancy is more likely tied to improved sanitation, public health practices, medical developments, and improved working conditions. In fact, Stephen Kunitz observed that life expectancy started increasing at least 50 years before our nutrition system started producing taller people. However, abundant food production does correlate with greater body height and life expectancy. This correlation has led to our deep conviction that increased height reflects improved nutrition and that taller height is a sign of improved health. However, based on my research over the last 37 years, it appears that this is a false idol that is driving the obesity epidemic. Certainly, sharply reduced infant mortality plays an important role in our increased life expectancy. However, many health authorities incorrectly associate increased life expectancy with improved health, and ignore the fact that our health is not very good. For example, among Americans over 65 years of age, 50% take 5 or more medications a day and 25% take 10 to 20 medications a day. In addition, a recent survey found that 86% of the U.S. work force has at least one chronic health problem, such as diabetes, heart disease, cancer, high blood pressure, asthma, depression or obesity.

Jose Granados reported that children born during the Great Depression experienced the greatest percentage increase in life expectancy of the 20th century. In spite of widespread decreased food availability and the stress of unemployment and poverty, virtually all age groups saw a reduction in mortality, including infants. Similar experiences were observed during food shortages in WW II Europe, the 1989-2000 economic crisis in Cuba, and the Great Leap Forward Famine in China. During the 20th century, Okinawans consumed a nourishing diet but it contained almost  40%  fewer calories during childhood and 20% fewer calories in adulthood compared to mainland Japan. However, Okinawans had a higher life expectancy compared to Japan and the world’s highest percentage of centenarians. (Male centenarians averaged 147 cm for males and 138 cm for females.)

I am not citing these findings to promote systematic under nutrition of our children. However, medical professionals and nutritionists need to re-evaluate traditional nutritional standards since they are not working as demonstrated by the current weight and health problems of our population. Hopefully, nutritional experts will formulate a new and effective dietary system within the context of our modern society that will promote both healthy children and adults.

The following sections summarize research on nutrition and growth over the past few decades to provide a basis for encouraging openness to new ideas so that caloric intake can be reduced for all age groups. More extensive details are available from the book: Human Body Size and the Laws of Scaling: Physiological, Performance, Growth, Longevity and Ecological Ramifications, Samaras TT (ed) and other publications cited in the bibliography.

Of course, one can cite opposing evidence to my findings, but it is obvious that there is something seriously wrong with the accepted approach to childhood nutrition and growth practices in view of our growing obesity and health problems. In addition, repeating the mistakes of the past with isolated adjustments is not likely to help us improve the current situation.

Maternal nutrition and childhood and adulthood health

Birth weight is correlated with the mother’s height, her pre-pregnancy weight and her weight gain during pregnancy. Nutrition drives to all three factors. While many believe that increases in these factors are desirable, there is evidence that they are not. For example, 

Tom Forsen found that adult males born to the thinnest mothers had the lowest mortality from coronary heart disease (CHD). In addition to increasing maternal weight, nutrition levels drive the child’s growth; e.g., Johan Eriksson found that males that were tallest at 11 years of age had the highest mortality from CHD in adulthood. In addition, Tessa Parsons reported that high early childhood protein intake was tied to adult obesity.

Japanese women have been gaining weight at a slower rate than other developed countries for over 30 years. When Japanese women get pregnant, they go on a restricted calorie diet and produce babies that average 200 grams lower than in 1980. The average birth weight for Japan is 3000 grams. While this moderately reduced birth weight may seem undesirable by conventional standards, the facts are that Japanese infant mortality is second lowest in the world and their life expectancy is third from the top. The 200-gram lighter birth weight of Japanese infants may have an advantage if excess weight is to be avoided in adulthood. For example, Henrik Sorensen found the difference between being an average weight adult and an obese adult is due to  ~ 125 gram difference in birth weight (3445 vs 3571 grams)  However, low birth weight (2500 grams) babies appear to be at higher risk of future adult chronic disease when they grow rapidly or become overweight adults.

Another example of lower birth weight not creating health problems involves infants exposed to the Dutch famine during their last trimester. Children conceived during the famine had a higher early mortality. However, at 57 years of age, they were found to have a substantially lower mortality than the same age adults who were conceived after the famine ended.

In view of the preceding, the current view of how much food mothers, infants and children should consume for optimum health needs re-evaluation.

Is higher birth weight necessary?

Birth weight has been increasing for many decades in the Western world. This is generally considered a good development and is tied to reduced infant mortality. However, almost all studies show that as birth weight  increases so does adult body mass index (BMI). In addition, based on over 153,000 children, Francisco Mardones found a positive linear relation between birth weight and later obesity.

Contrary to popular opinion, a number of studies indicate that moderately lower birth weight is not a risk factor for infants. For example, a Norwegian study found that infants born to Vietnamese mothers were the lowest in birth weight compared to other ethnic groups and had the lowest infant mortality. However, when all ethnic groups were considered, birth weight was not a factor in terms of infant mortality. An earlier study found that Vietnamese mothers born in Vietnam but living in Australia had infants with lower birth weight and lower infant mortality when compared to higher weight infants whose Vietnamese mothers were born in Australia.

Malcolm Zaretsky studied about 26,000 twins that were WW II veterans and found that identifical twins had a life expectancy of 82 years and fraternal twins averaged 80.5 years. Another study found that WW II veterans (essentially singletons) had a life expectancy of 78 years. Twins average 1000 grams lighter in birth weight vs. singletons, and identifcal twins average about 150 grams lighter than fraternal twins. Thus, lower birth weight did not appear to be a negative factor in terms of longevity.

As mentioned, Japanese infants have seen a reduction in birth weight, but Japan is still second lowest in the world in terms of infant mortality and third from the top of the list for life expectancy. During the 20th century, Patrick Bradley reported that the non-developed world was characterized by lower birth weight compared to the West but diabetes and CVD were almost absent. As mentioned, during the Great Depression lower income women ate less than normal and many infants were on the lower end of the usual birth weight. Yet, infant mortality declined.

It appears that a high birth weight is not necessary for good health and low infant mortality when a well-balanced diet is provided in a wholesome environment with good medical care.

Accelerated growth and early maturation

Elisabetta Marini and others recently noted that over nutrition, higher birth weight, rapid growth and taller height increases health problems at older ages and reduces longevity. Tessa Parsons also reported that rapid growth in height and higher birth weight during childhood increases the risk of obesity at 33 years of age.  In contrast, Barbara Alexander found that slow growth in early infancy reduces CVD risk. Another study found that males who reach sexual maturity before 18 years of age have 3 times the risk of adult prostate cancer compared to those who reach it after 20 years of age.

David Freedman also found that children who were tall at about 8 years of age had 5 times the risk of becoming obese adults compared to children that were shorter than average.  Freedman also found that children who experienced adiposity rebound before 5 years of age were likely to have an adult BMI that is 4.5 points higher than those who reached adiposity rebound after 7 years of age.

Separate reports by Atul Singhal, Jonathan Wells, and Andrzej Bartke have reported that rapid catch up growth or body size discordance between birth weight and weight at older ages are related to increased risk of age related diseases. Singhal also noted that overnutritiion during infancy increases the risk of CVD. Another study found that children are receiving about 20% more calories than they need.

A study on early sexual maturity of females found that those who reached menarche at 11 years of age had about a 20% higher mortality in adulthood vs. those that reached menarche at 17 years of age.

It appears that promoting rapid growth has many negative ramifications in terms of health and the prospects of later obesity. In contrast, slower growth may be protective due to differences in resource allocation during growth. For example, rapid growth may divert resources needed for cell maintenance and repair in order to expand the number of cells in the body. This thesis is supported by 20th century findings from Okinawa. During the 20th century, Okinawan children consumed almost 40% fewer calories than mainland Japanese children. They were also smaller but had a longer life expectancy and the highest percentage of centenarians in the world.

Are low calorie diets dangerous?

David Rollo reported that over 80 years of research has shown nutritious low calorie diets stunt growth but are not harmful to health and longevity. In fact, they appear to improve health, reduce the incidence of chronic diseases and increase longevity. Most studies have been based on animal populations and have shown that a calorie restricted diet started early in life is beneficial. As mentioned before, the low calorie diet of Okinawan children seems to promote health and longevity.

Caloric restriction for adults also appears to be beneficial. For example, a Spanish study placed a cohort of elderly on a normal calorie diet for one day and a 50% lower diet the other day. When compared to a second cohort that ate the same number of calories every day, the reduce calorie cohort had much lower death rate and spent fewer days being sick.

Bradley Willcox reported that a study of elderly Hawaiian Japanese found males who ate fewer calories had lower mortality. Mortality declined progressively down to a daily intake of 970 kcal. However, below this caloric intake, mortality began to increase.

Male vs. Female Longevity and Size

Most medical authorities explain the difference in longevity between men and women as due to hormonal differences. Hormones certainly play a role, but based on recent research, it appears that male-female body size differences are the major cause of greater female longevity.

Virtually all populations of humans show that women are smaller than men and live longer. When I looked at US men and women who were born around 1980, I found that men were 9% taller and their life expectancy was 9% lower than that of women. Other findings have supported this result. For example, Dennis Miller found that when he compared deceased men and women of the same height, their longevity was about the same. David Rollo found that the difference in longevity between male and female rodents was due to their differences in body size. In addition, Holly Brown-Borg reported that dwarf male rodents lived longer than normal size female siblings.

Sarah Moore and Kenneth Wilson found that larger males had a higher mortality compared to smaller female animals. They also found that when females are larger than males, the females experience higher mortality than smaller males. Body size was related to higher parasite levels, which appeared to promote increased mortality. Both larger males and females had higher parasitic levels compared to their smaller counterparts.

Villagrande Strisaili is a remote village in Sardinia noted for its great longevity and the short stature of its population. While most countries show female centenarians outnumber males by up to 14 times, the Sardinians have a one-to-one ratio. While the men are taller than women, overall they are quite short at 160 cm. Thus, it is unlikely that differences in hormones explain the worldwide differences in longevity between men and women.

Maximizing height and reduced longevity

The widespread belief that taller people are healthier and livelonger than shorter ones is based on the much higher life expectancy in the developed world that parallels our increase in height. There are certainly many studies that show taller people within the developed world have a lower mortality than shorter people. These studies primarily track people from their 20s to 50, 60 or 70 years of age. A potential confounder is that people in higher economic groups, who are also taller, have substantially lower death rates compared to people in lower economic brackets who are shorter.

The belief that children should reach their maximum genetic height potential is widespread. However, no one currently believes that reaching our maximum genetic potential for weight is a desirable goal.  Years of research have shown that even moderate overweight is dangerous for our health. However, in the 19th century many believed that being overweight was a positive value reflecting opulence and a higher standard of living. Evidence is provided below to question our strongly held belief that taller height is a sign of good health.

Many studies reveal that there are no differences between taller and shorter people. Also, a number of studies have found shorter people have the same or lower all-cause or cardiovascular disease mortality compared to taller ones. While researchers adjust for various variables, their adjustments are crude and inexact. The reason that conflicting results occur is that height is only about 10% of the longevity picture. Genetics, body mass index, diet, smoking, economics, medical care, etc. have a much larger impact.

A wide range of animal and human studies provide consistent evidence that smaller bodies tend to live longer. A brief review of these facts is presented next.

Alex Comfort and many other researchers have reported that within the same species, smaller individuals usually live longer than bigger ones. It is well known that various animal groups support this statement. For example, smaller dogs, mice, rats, and horses live longer than bigger ones. In addition, the Asian elephant lives about 7 years longer than the larger African elephant.

Andrzej Bartke recently published a review paper entitled: Healthy Aging: Is Smaller Better? His evaluation of animal and human studies led him to conclude that smaller body size was an advantage for achieving better health and longevity.

Martin Holzenberger tracked 1.3 million men over a 70-year period and found that shorter men lived longer. Subsequently, he also reported that they lost .8 yr/cm of increased height. More recently, Luisa Salaris and Michel Poulain studied a sample of about 500 men in an isolated mountain village in Sardinia. This village, Villagrande Strisaili, was previously found to have the highest longevity in Sardinia and other European countries and the men averaged 160 cm. Within this population, elderly shorter men were found to live about 2 years longer than taller ones. The findings were consistent with earlier findings in Sardinia, which found that as a region got shorter, longevity increased.

US ethnic mortality data from 1985 to 2000 shows that Asians have the lowest all-cause mortality while Blacks and Whites have roughly double the mortality. Latinos and Native Americans fit in-between. Yet, Asians were the shortest and Blacks and Whites the tallest of the ethnic groups. Latinos and Native Americans were in-between in height. These findings are based on about 18 million deaths.

I have conducted or reviewed studies on longevity and mortality data based on Ohio, Sweden, Paris, Hawaii, and Okinawa. In addition, I have looked at deceased San Diego veterans, baseball players, football players, basketball players, and famous people and these data provide consistent results that show shorter people do better.

The top life expectancy populations around the end of the 20th century were Andorra, Macao, Japan, Singapore and Hong Kong. Their average ranking was 3.5 from the top. In contrast, the top tallest populations in Western Europe (Scandinavia, The Netherlands, and Germany) ranked 28 from the top. While a ranking of 28 is still excellent, it is substantially lower than for the shorter group.

The Dutch have increased in height in recent decades, but their life expectancy ranking has dropped from 5 to 21. While smoking may be part of it, it does not explain the entire decline in longevity ranking of the Dutch. However, the decline is consistent with many findings showing increased height has a negative impact on longevity.

Cancer and height

Many researchers now believe that greater height is tied to increased cancer risk. Based on a review of about 7000 papers and reports, the World Cancer Research Fund published a report in 2007, which concluded that several major cancers were related to greater height. In addition, a review published in 2012 found similar results. Also, David Gunnell did about 300 studies in 2001 and found that shorter people had lower cancer.

Cardiovascular disease and height

Some researchers quickly dismiss the idea that shorter people may have inherently lower CHD. Yet, many studies have shown that populations where there is virtually no evidence of CHD or stroke, male height ranges from under 152 cm to 163 cm. These include mid 20th century studies of Fiji, Cook, Solomon and Papua New Guinea Islands, Kalahari bushmen, and Congo pygmies. Other populations with little to no CHD include Kitava Island, Yanomamo and Xingu Indians, and the people of Vilcabamba. Of course, it is well known that the southern Europeans have traditionally had lower CHD compared to the taller north. In the 1960’s, Keys found that the relatively short people in the Greek island of Crete, had 1/10 the heart disease of northern Europeans.  Colin Campbell also reported that American males had 17 times the mortality from CHD as shorter rural Chinese males. In addition, late in the 20th century, the relatively shorter people of Japan, Hong Kong, France, Portugal, Spain and Italy had the lowest CHD mortality in the developed world.

An interesting paradox exists for the proponents of lower CHD and taller height. For example, Walter Willett reported that CHD was extremely rare in the early 1900s. Yet, Americans were a few inches shorter than they are today. In addition, up to 1970, higher income men had higher CHD compared to lower income men. After 1970, the situation reversed and working class people had higher death rates from CHD compared to higher income groups. Higher income people were taller in both periods. Therefore, taller height was not the cause for lower CHD after 1970.

Dog studies support the previous findings. Agneta Egenvall reported that smaller dogs had a substantially lower risk of heart failure. For example, the miniature dachshund has a mortality risk of 0.3 vs. 21 for the Great Dane. This 70 to 1 advantage is most likely a major reason for why smaller dogs live longer than bigger ones.

Centenarians

While tall people can reach 100 years of age, I am not aware of a peer-reviewed study that has found tall people are predominately centenarians. All the studies I have seen show centenarians to be short or medium in height. For example, Chan, Suzuki and Yamamoto reported that being short and lean was an important factor for reaching 100 years of age. In addition, an Italian report based on 2500 centenarians concluded that being short and lean was an important factor.

Okinawan male centenarians average 147 cm and Sardinian centenarians were shorter than 157 cm. They also are at the top of the list for the highest world percentage of people who reach the 100-year mark. A recent Cuban study found the average male height of centenarians to be about 155 cm. Supercentenarians is rare, but they were also found to be short.

Leonid and Natalia Gavrilov found WW I veterans were more likely to reach 100 years of age if they were medium in height. However, American researchers, Roth, Ingram, and Lane, found centenarians were often of small stature.

Data from Sicily, Hungary and Poland also found that short height was common to centenarians. Of course, throughout most of the world, shorter women centenarians outnumber taller men by 3 to 14 times.

Sardinia provides remarkable findings in terms of the extreme longevity index. This index measures the number of people who reach 100 years of age out of every 1000 birth cohorts. Villagrande Strisaili, the shortest people in Sardinia, has the highest longevity index of 10.8. People in long-living region within Sardinia, known as the blue zone, are taller than the people in Villagrande, and this taller region averages 5.1. The remainder of Sardinia, which is taller than the previous two groups, averages 2.1.

If being short was a health disadvantage, it is hard to see how they would be over-represented in the general population of centenarians. However, it should be pointed out that with advances in medicine, more tall people would be reaching the centenarian milestone.

Reasons for conflicting findings

Height represents about 10% of the longevity picture. Many other factors can overwhelm the benefits of shorter height. These include economic status, BMI, diet, exercise, smoking, and lack of exercise, genetics, stress and trauma. During the 20th century, poorer people tended to be obese and were at higher risk for CVD and diabetes compared to better off classes. Better off classes were taller as well. The Spanish and Sardinian males probably reflect a more homogeneous lifestyle and genetic background than many Western populations. That’s probably the reason that they showed a consistent negative association between height and longevity.

In recent years, catch-up growth of low birth weight children has been found to correlate with adult diabetes and CVD. An excessive diet may cause these effects by increasing cholesterol levels and adult weight.

A study found that 50% short children had pathological conditions. If this is widespread, then their shorter height and health problems can be incorrectly connected as cause and effect.  Note that height tends to track through the growth period.

Another factor for potential confounding is BMI. Most studies that find tall people have lower mortality do not compare short and tall groups of similar body types. To do this, they would have to compare taller people with BMIs that are higher than shorter people. The reasons for this are that when the body increases in height by 10%, its weight increases by 33%. Thus, the taller cohort of a study should have a 10% higher BMI compared to the shorter cohort. Song and Song found that shorter people in their study tended to have higher BMIs.

Conclusions and Recommendations

Studies can be provided to counter the preceding findings. However, most studies supporting the “taller is healthier “ thesis are mortality studies, not longevity studies that track relatively homogeneous groups of people through their entire life cycle. In contrast, the evidence supporting the “smaller is healthier” thesis is based on extensive animal and human research, including cohort, ecological, descriptive and centenarian studies. In addition, support is provided by studies, which show that reduced nutrition and growth appear to reduce adult mortality and increase longevity. These include the Cuban economic crisis; the Finnish, Dutch and Chinese famines; WW II food shortages and the Great Depression. Certainly, one can challenge any of these findings on an individual basis but it is hard to believe that all these independent studies provide such consistent evidence by accident or confounding factors.

My conclusions are based on numerous studies that show higher protein intake, increased birth weight, rapid growth and taller height are related to the current obesity epidemic. For example, Tessa Parsons reported that high protein intake during early childhood promotes the risk of obesity in young adulthood.  Cornelia Metzger also reported that increased protein intake early in life increased childhood obesity. PAO Montero found that rapid growth in height and weight during the first 42 months of life increased the risk of childhood obesity.

Some recommendations for countering the growing trend towards increased obesity and associated chronic disease follow.

1.We need to take a new look at current food system policies and the Western diet and                             develop a healthful diet while minimizing calorie consumption, salt intake and                                     avoiding excessive protein intake. (The plant-based diet appears to have                                     substantial support.)

2. Deemphasize the importance of higher birth weight, rapid growth and attaining taller height.

3. Emphasize education in good nutrition.

4. Establish clinics for new mothers and young children to teach portion control and healthful                         nutrition. Student participation in preparing healthful meals would also help change                         current nutrition problems.

5. Increase taxes on junk and other undesirable food. Healthful food should be cheaper than             unhealthful food.

6. Shift food subsidies to healthful, low calorie, and plant-based foods.

7. Reward normal weight children with special trips and awards.

If the recommendations seem draconian, they are. Failure to take strong and early action will increase our already bloated deficit. In the coming decades, we are looking at increased health costs of trillions of dollars a year. We can’t afford a moderate program that will require decades to implement.

Bibliography

Bartke A. Healthy aging: Is smaller better? A mini-Review. Gerontology, 2012, 58:337-43.

Campbell TC and Campbell TM. The china study: Startling implications for diet, weight loss and long-term health. Ben Bella Books, Dallas, Texas, 2006.

Cannon G. The fate of nations: Food and nutrition policy in the new world. Royal Society, Caroline Walker Trust, London, 2003.

Eberhardt MS, Ingram DD, Makuc DM, et al. Urban and Rural Health Chartbook, Health, United States, 2001, Hyattsville, Maryland, National Center for Health Statistics, 2001.

Elrick H, Samaras TT, Demas A. Missing links in the obesity epidemic. Nutrition Research 2002; 22: 1101-1123.

Killewo J, Heggenhougen HK, Quah SR (eds). Epidemiology and Demography in Public Health, San Diego, Academic Press, 2010. Longevity in Specific Populations, TT Samaras, pp. 415-420.

Matsuyama K, Gale J. Diets by pregnant women spur underweight babies in Japan. Bloomberg News.com  Oct 28, 2010.

Parsons TJ, Power C, Logan S, Summerbell CD. Childhood predictors of adult obesity: a systematic review. International Journal of Obesity. 1999; 23, Suppl 8: S1-S107.

Popkin, B. The World is Fat. Avery, New York, 2009.

Rollo CD.  Growth negatively impacts the life span of mammals. Evolution and Development 2002; 4: 55-61.

Salaris L, Poulain M, and Samaras TT. Height and survival at older ages among males born in an in-land village in Sardinia (1866-1915). Biodemography and Social Biology, 2012; 58:1, 1-13.

Samaras TT. Commentary. Human growth, height, size: Reasons to be small, World Nutrition, 2011, 2,3:108-135

Samaras TT. Ramifications of increasing birth weight, accelerated growth and greater height on health, the obesity epidemic, and longevity, Journal of Chinese Clinical Medicine, 2010, 5(8): 433-449.

Samaras TT, Storms LH. Impact of height and weight on life span. Bulletin of the World Health Organization 1992; 70: 259-267.

Samaras TT. Role of height in cancer and cardiovascular disease. Journal of Chinese Clinical Medicine 2010, 51, 87-99.

Samaras TT. Are 20th-century recommendations for growth and height correct? A review. South African Journal of Clinical Nutrition 2009, 22, 171-178.

Samaras TT. Should we be concerned over increasing body height and weight? Experimental Gerontology 2009 ; 44: 83-92.

Samaras TT, Elrick H, Storms LH. Birth weight, rapid growth, cancer, and longevity: a review. Journal of the National Medical Association 2003; 95: 1170-1183.

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Childhood and Adult Obesity--a new approach provides the world with a challenge

 Childhood and Adult Obesity--a new approach provides the world with a challenge

                                                Thomas T. Samaras

                                                Reventropy Associates

                                                San Diego, CA

Many health authorities subscribe to the belief that abundant nutrition, high birth weight, rapid growth and taller height characterize healthy children. Unfortunately, this approach appears to have produced the current epidemics in obesity and chronic diseases.

Obesity and nutrition experts such as, Barry Popkin, Colin Campbell, Hugh Trowell and Denis Burkitt, have noted that the Western food system developed over the last 150 years has been devastating to our health. These experts attribute our health problems to excessive animal protein and processed foods. For example, the combination of modern nutrition, greater height and higher body mass index have led to undesirable higher levels of cholesterol, glucose, insulin, C-reactive protein, insulin-like growth factor-1, and lower levels of sex hormone binding globulin, adiponectin, and high density lipoprotein. Undesirable levels of these factors are also related to cardiovascular disease (CVD), type 2 diabetes, and many cancers.

Many researchers attribute our increased life expectancy over the last 150 years to our food system. However, increased life expectancy is more likely tied to improved sanitation, public health practices, medical developments, and improved working conditions. In fact, Stephen Kunitz observed that life expectancy started increasing at least 50 years before our nutrition system started producing taller people. However, abundant food production does correlate with greater body height and life expectancy. This correlation has led to our deep conviction that increased height reflects improved nutrition and that taller height is a sign of improved health. However, based on my research over the last 37 years, it appears that this is a false idol that is driving the obesity epidemic. Certainly, sharply reduced infant mortality plays an important role in our increased life expectancy. However, many health authorities incorrectly associate increased life expectancy with improved health, and ignore the fact that our health is not very good. For example, among Americans over 65 years of age, 50% take 5 or more medications a day and 25% take 10 to 20 medications a day. In addition, a recent survey found that 86% of the U.S. work force has at least one chronic health problem, such as diabetes, heart disease, cancer, high blood pressure, asthma, depression or obesity.

Jose Granados reported that children born during the Great Depression experienced the greatest percentage increase in life expectancy of the 20th century. In spite of widespread decreased food availability and the stress of unemployment and poverty, virtually all age groups saw a reduction in mortality, including infants. Similar experiences were observed during food shortages in WW II Europe, the 1989-2000 economic crisis in Cuba, and the Great Leap Forward Famine in China. During the 20th century, Okinawans consumed a nourishing diet but it contained almost  40%  fewer calories during childhood and 20% fewer calories in adulthood compared to mainland Japan. However, Okinawans had a higher life expectancy compared to Japan and the world’s highest percentage of centenarians. (Male centenarians averaged 147 cm for males and 138 cm for females.)

I am not citing these findings to promote systematic under nutrition of our children. However, medical professionals and nutritionists need to re-evaluate traditional nutritional standards since they are not working as demonstrated by the current weight and health problems of our population. Hopefully, nutritional experts will formulate a new and effective dietary system within the context of our modern society that will promote both healthy children and adults.

The following sections summarize research on nutrition and growth over the past few decades to provide a basis for encouraging openness to new ideas so that caloric intake can be reduced for all age groups. More extensive details are available from the book: Human Body Size and the Laws of Scaling: Physiological, Performance, Growth, Longevity and Ecological Ramifications, Samaras TT (ed) and other publications cited in the bibliography.

Of course, one can cite opposing evidence to my findings, but it is obvious that there is something seriously wrong with the accepted approach to childhood nutrition and growth practices in view of our growing obesity and health problems. In addition, repeating the mistakes of the past with isolated adjustments is not likely to help us improve the current situation.

Maternal nutrition and childhood and adulthood health

Birth weight is correlated with the mother’s height, her pre-pregnancy weight and her weight gain during pregnancy. Nutrition drives to all three factors. While many believe that increases in these factors are desirable, there is evidence that they are not. For example, 

Tom Forsen found that adult males born to the thinnest mothers had the lowest mortality from coronary heart disease (CHD). In addition to increasing maternal weight, nutrition levels drive the child’s growth; e.g., Johan Eriksson found that males that were tallest at 11 years of age had the highest mortality from CHD in adulthood. In addition, Tessa Parsons reported that high early childhood protein intake was tied to adult obesity.

Japanese women have been gaining weight at a slower rate than other developed countries for over 30 years. When Japanese women get pregnant, they go on a restricted calorie diet and produce babies that average 200 grams lower than in 1980. The average birth weight for Japan is 3000 grams. While this moderately reduced birth weight may seem undesirable by conventional standards, the facts are that Japanese infant mortality is second lowest in the world and their life expectancy is third from the top. The 200-gram lighter birth weight of Japanese infants may have an advantage if excess weight is to be avoided in adulthood. For example, Henrik Sorensen found the difference between being an average weight adult and an obese adult is due to  ~ 125 gram difference in birth weight (3445 vs 3571 grams)  However, low birth weight (2500 grams) babies appear to be at higher risk of future adult chronic disease when they grow rapidly or become overweight adults.

Another example of lower birth weight not creating health problems involves infants exposed to the Dutch famine during their last trimester. Children conceived during the famine had a higher early mortality. However, at 57 years of age, they were found to have a substantially lower mortality than the same age adults who were conceived after the famine ended.

In view of the preceding, the current view of how much food mothers, infants and children should consume for optimum health needs re-evaluation.

Is higher birth weight necessary?

Birth weight has been increasing for many decades in the Western world. This is generally considered a good development and is tied to reduced infant mortality. However, almost all studies show that as birth weight  increases so does adult body mass index (BMI). In addition, based on over 153,000 children, Francisco Mardones found a positive linear relation between birth weight and later obesity.

Contrary to popular opinion, a number of studies indicate that moderately lower birth weight is not a risk factor for infants. For example, a Norwegian study found that infants born to Vietnamese mothers were the lowest in birth weight compared to other ethnic groups and had the lowest infant mortality. However, when all ethnic groups were considered, birth weight was not a factor in terms of infant mortality. An earlier study found that Vietnamese mothers born in Vietnam but living in Australia had infants with lower birth weight and lower infant mortality when compared to higher weight infants whose Vietnamese mothers were born in Australia.

Malcolm Zaretsky studied about 26,000 twins that were WW II veterans and found that identifical twins had a life expectancy of 82 years and fraternal twins averaged 80.5 years. Another study found that WW II veterans (essentially singletons) had a life expectancy of 78 years. Twins average 1000 grams lighter in birth weight vs. singletons, and identifcal twins average about 150 grams lighter than fraternal twins. Thus, lower birth weight did not appear to be a negative factor in terms of longevity.

As mentioned, Japanese infants have seen a reduction in birth weight, but Japan is still second lowest in the world in terms of infant mortality and third from the top of the list for life expectancy. During the 20th century, Patrick Bradley reported that the non-developed world was characterized by lower birth weight compared to the West but diabetes and CVD were almost absent. As mentioned, during the Great Depression lower income women ate less than normal and many infants were on the lower end of the usual birth weight. Yet, infant mortality declined.

It appears that a high birth weight is not necessary for good health and low infant mortality when a well-balanced diet is provided in a wholesome environment with good medical care.

Accelerated growth and early maturation

Elisabetta Marini and others recently noted that over nutrition, higher birth weight, rapid growth and taller height increases health problems at older ages and reduces longevity. Tessa Parsons also reported that rapid growth in height and higher birth weight during childhood increases the risk of obesity at 33 years of age.  In contrast, Barbara Alexander found that slow growth in early infancy reduces CVD risk. Another study found that males who reach sexual maturity before 18 years of age have 3 times the risk of adult prostate cancer compared to those who reach it after 20 years of age.

David Freedman also found that children who were tall at about 8 years of age had 5 times the risk of becoming obese adults compared to children that were shorter than average.  Freedman also found that children who experienced adiposity rebound before 5 years of age were likely to have an adult BMI that is 4.5 points higher than those who reached adiposity rebound after 7 years of age.

Separate reports by Atul Singhal, Jonathan Wells, and Andrzej Bartke have reported that rapid catch up growth or body size discordance between birth weight and weight at older ages are related to increased risk of age related diseases. Singhal also noted that overnutritiion during infancy increases the risk of CVD. Another study found that children are receiving about 20% more calories than they need.

A study on early sexual maturity of females found that those who reached menarche at 11 years of age had about a 20% higher mortality in adulthood vs. those that reached menarche at 17 years of age.

It appears that promoting rapid growth has many negative ramifications in terms of health and the prospects of later obesity. In contrast, slower growth may be protective due to differences in resource allocation during growth. For example, rapid growth may divert resources needed for cell maintenance and repair in order to expand the number of cells in the body. This thesis is supported by 20th century findings from Okinawa. During the 20th century, Okinawan children consumed almost 40% fewer calories than mainland Japanese children. They were also smaller but had a longer life expectancy and the highest percentage of centenarians in the world.

Are low calorie diets dangerous?

David Rollo reported that over 80 years of research has shown nutritious low calorie diets stunt growth but are not harmful to health and longevity. In fact, they appear to improve health, reduce the incidence of chronic diseases and increase longevity. Most studies have been based on animal populations and have shown that a calorie restricted diet started early in life is beneficial. As mentioned before, the low calorie diet of Okinawan children seems to promote health and longevity.

Caloric restriction for adults also appears to be beneficial. For example, a Spanish study placed a cohort of elderly on a normal calorie diet for one day and a 50% lower diet the other day. When compared to a second cohort that ate the same number of calories every day, the reduce calorie cohort had much lower death rate and spent fewer days being sick.

Bradley Willcox reported that a study of elderly Hawaiian Japanese found males who ate fewer calories had lower mortality. Mortality declined progressively down to a daily intake of 970 kcal. However, below this caloric intake, mortality began to increase.

Male vs. Female Longevity and Size

Most medical authorities explain the difference in longevity between men and women as due to hormonal differences. Hormones certainly play a role, but based on recent research, it appears that male-female body size differences are the major cause of greater female longevity.

Virtually all populations of humans show that women are smaller than men and live longer. When I looked at US men and women who were born around 1980, I found that men were 9% taller and their life expectancy was 9% lower than that of women. Other findings have supported this result. For example, Dennis Miller found that when he compared deceased men and women of the same height, their longevity was about the same. David Rollo found that the difference in longevity between male and female rodents was due to their differences in body size. In addition, Holly Brown-Borg reported that dwarf male rodents lived longer than normal size female siblings.

Sarah Moore and Kenneth Wilson found that larger males had a higher mortality compared to smaller female animals. They also found that when females are larger than males, the females experience higher mortality than smaller males. Body size was related to higher parasite levels, which appeared to promote increased mortality. Both larger males and females had higher parasitic levels compared to their smaller counterparts.

Villagrande Strisaili is a remote village in Sardinia noted for its great longevity and the short stature of its population. While most countries show female centenarians outnumber males by up to 14 times, the Sardinians have a one-to-one ratio. While the men are taller than women, overall they are quite short at 160 cm. Thus, it is unlikely that differences in hormones explain the worldwide differences in longevity between men and women.

Maximizing height and reduced longevity

The widespread belief that taller people are healthier and livelonger than shorter ones is based on the much higher life expectancy in the developed world that parallels our increase in height. There are certainly many studies that show taller people within the developed world have a lower mortality than shorter people. These studies primarily track people from their 20s to 50, 60 or 70 years of age. A potential confounder is that people in higher economic groups, who are also taller, have substantially lower death rates compared to people in lower economic brackets who are shorter.

The belief that children should reach their maximum genetic height potential is widespread. However, no one currently believes that reaching our maximum genetic potential for weight is a desirable goal.  Years of research have shown that even moderate overweight is dangerous for our health. However, in the 19th century many believed that being overweight was a positive value reflecting opulence and a higher standard of living. Evidence is provided below to question our strongly held belief that taller height is a sign of good health.

Many studies reveal that there are no differences between taller and shorter people. Also, a number of studies have found shorter people have the same or lower all-cause or cardiovascular disease mortality compared to taller ones. While researchers adjust for various variables, their adjustments are crude and inexact. The reason that conflicting results occur is that height is only about 10% of the longevity picture. Genetics, body mass index, diet, smoking, economics, medical care, etc. have a much larger impact.

A wide range of animal and human studies provide consistent evidence that smaller bodies tend to live longer. A brief review of these facts is presented next.

Alex Comfort and many other researchers have reported that within the same species, smaller individuals usually live longer than bigger ones. It is well known that various animal groups support this statement. For example, smaller dogs, mice, rats, and horses live longer than bigger ones. In addition, the Asian elephant lives about 7 years longer than the larger African elephant.

Andrzej Bartke recently published a review paper entitled: Healthy Aging: Is Smaller Better? His evaluation of animal and human studies led him to conclude that smaller body size was an advantage for achieving better health and longevity.

Martin Holzenberger tracked 1.3 million men over a 70-year period and found that shorter men lived longer. Subsequently, he also reported that they lost .8 yr/cm of increased height. More recently, Luisa Salaris and Michel Poulain studied a sample of about 500 men in an isolated mountain village in Sardinia. This village, Villagrande Strisaili, was previously found to have the highest longevity in Sardinia and other European countries and the men averaged 160 cm. Within this population, elderly shorter men were found to live about 2 years longer than taller ones. The findings were consistent with earlier findings in Sardinia, which found that as a region got shorter, longevity increased.

US ethnic mortality data from 1985 to 2000 shows that Asians have the lowest all-cause mortality while Blacks and Whites have roughly double the mortality. Latinos and Native Americans fit in-between. Yet, Asians were the shortest and Blacks and Whites the tallest of the ethnic groups. Latinos and Native Americans were in-between in height. These findings are based on about 18 million deaths.

I have conducted or reviewed studies on longevity and mortality data based on Ohio, Sweden, Paris, Hawaii, and Okinawa. In addition, I have looked at deceased San Diego veterans, baseball players, football players, basketball players, and famous people and these data provide consistent results that show shorter people do better.

The top life expectancy populations around the end of the 20th century were Andorra, Macao, Japan, Singapore and Hong Kong. Their average ranking was 3.5 from the top. In contrast, the top tallest populations in Western Europe (Scandinavia, The Netherlands, and Germany) ranked 28 from the top. While a ranking of 28 is still excellent, it is substantially lower than for the shorter group.

The Dutch have increased in height in recent decades, but their life expectancy ranking has dropped from 5 to 21. While smoking may be part of it, it does not explain the entire decline in longevity ranking of the Dutch. However, the decline is consistent with many findings showing increased height has a negative impact on longevity.

Cancer and height

Many researchers now believe that greater height is tied to increased cancer risk. Based on a review of about 7000 papers and reports, the World Cancer Research Fund published a report in 2007, which concluded that several major cancers were related to greater height. In addition, a review published in 2012 found similar results. Also, David Gunnell did about 300 studies in 2001 and found that shorter people had lower cancer.

Cardiovascular disease and height

Some researchers quickly dismiss the idea that shorter people may have inherently lower CHD. Yet, many studies have shown that populations where there is virtually no evidence of CHD or stroke, male height ranges from under 152 cm to 163 cm. These include mid 20th century studies of Fiji, Cook, Solomon and Papua New Guinea Islands, Kalahari bushmen, and Congo pygmies. Other populations with little to no CHD include Kitava Island, Yanomamo and Xingu Indians, and the people of Vilcabamba. Of course, it is well known that the southern Europeans have traditionally had lower CHD compared to the taller north. In the 1960’s, Keys found that the relatively short people in the Greek island of Crete, had 1/10 the heart disease of northern Europeans.  Colin Campbell also reported that American males had 17 times the mortality from CHD as shorter rural Chinese males. In addition, late in the 20th century, the relatively shorter people of Japan, Hong Kong, France, Portugal, Spain and Italy had the lowest CHD mortality in the developed world.

An interesting paradox exists for the proponents of lower CHD and taller height. For example, Walter Willett reported that CHD was extremely rare in the early 1900s. Yet, Americans were a few inches shorter than they are today. In addition, up to 1970, higher income men had higher CHD compared to lower income men. After 1970, the situation reversed and working class people had higher death rates from CHD compared to higher income groups. Higher income people were taller in both periods. Therefore, taller height was not the cause for lower CHD after 1970.

Dog studies support the previous findings. Agneta Egenvall reported that smaller dogs had a substantially lower risk of heart failure. For example, the miniature dachshund has a mortality risk of 0.3 vs. 21 for the Great Dane. This 70 to 1 advantage is most likely a major reason for why smaller dogs live longer than bigger ones.

Centenarians

While tall people can reach 100 years of age, I am not aware of a peer-reviewed study that has found tall people are predominately centenarians. All the studies I have seen show centenarians to be short or medium in height. For example, Chan, Suzuki and Yamamoto reported that being short and lean was an important factor for reaching 100 years of age. In addition, an Italian report based on 2500 centenarians concluded that being short and lean was an important factor.

Okinawan male centenarians average 147 cm and Sardinian centenarians were shorter than 157 cm. They also are at the top of the list for the highest world percentage of people who reach the 100-year mark. A recent Cuban study found the average male height of centenarians to be about 155 cm. Supercentenarians is rare, but they were also found to be short.

Leonid and Natalia Gavrilov found WW I veterans were more likely to reach 100 years of age if they were medium in height. However, American researchers, Roth, Ingram, and Lane, found centenarians were often of small stature.

Data from Sicily, Hungary and Poland also found that short height was common to centenarians. Of course, throughout most of the world, shorter women centenarians outnumber taller men by 3 to 14 times.

Sardinia provides remarkable findings in terms of the extreme longevity index. This index measures the number of people who reach 100 years of age out of every 1000 birth cohorts. Villagrande Strisaili, the shortest people in Sardinia, has the highest longevity index of 10.8. People in long-living region within Sardinia, known as the blue zone, are taller than the people in Villagrande, and this taller region averages 5.1. The remainder of Sardinia, which is taller than the previous two groups, averages 2.1.

If being short was a health disadvantage, it is hard to see how they would be over-represented in the general population of centenarians. However, it should be pointed out that with advances in medicine, more tall people would be reaching the centenarian milestone.

Reasons for conflicting findings

Height represents about 10% of the longevity picture. Many other factors can overwhelm the benefits of shorter height. These include economic status, BMI, diet, exercise, smoking, and lack of exercise, genetics, stress and trauma. During the 20th century, poorer people tended to be obese and were at higher risk for CVD and diabetes compared to better off classes. Better off classes were taller as well. The Spanish and Sardinian males probably reflect a more homogeneous lifestyle and genetic background than many Western populations. That’s probably the reason that they showed a consistent negative association between height and longevity.

In recent years, catch-up growth of low birth weight children has been found to correlate with adult diabetes and CVD. An excessive diet may cause these effects by increasing cholesterol levels and adult weight.

A study found that 50% short children had pathological conditions. If this is widespread, then their shorter height and health problems can be incorrectly connected as cause and effect.  Note that height tends to track through the growth period.

Another factor for potential confounding is BMI. Most studies that find tall people have lower mortality do not compare short and tall groups of similar body types. To do this, they would have to compare taller people with BMIs that are higher than shorter people. The reasons for this are that when the body increases in height by 10%, its weight increases by 33%. Thus, the taller cohort of a study should have a 10% higher BMI compared to the shorter cohort. Song and Song found that shorter people in their study tended to have higher BMIs.

Conclusions and Recommendations

Studies can be provided to counter the preceding findings. However, most studies supporting the “taller is healthier “ thesis are mortality studies, not longevity studies that track relatively homogeneous groups of people through their entire life cycle. In contrast, the evidence supporting the “smaller is healthier” thesis is based on extensive animal and human research, including cohort, ecological, descriptive and centenarian studies. In addition, support is provided by studies, which show that reduced nutrition and growth appear to reduce adult mortality and increase longevity. These include the Cuban economic crisis; the Finnish, Dutch and Chinese famines; WW II food shortages and the Great Depression. Certainly, one can challenge any of these findings on an individual basis but it is hard to believe that all these independent studies provide such consistent evidence by accident or confounding factors.

My conclusions are based on numerous studies that show higher protein intake, increased birth weight, rapid growth and taller height are related to the current obesity epidemic. For example, Tessa Parsons reported that high protein intake during early childhood promotes the risk of obesity in young adulthood.  Cornelia Metzger also reported that increased protein intake early in life increased childhood obesity. PAO Montero found that rapid growth in height and weight during the first 42 months of life increased the risk of childhood obesity.

Some recommendations for countering the growing trend towards increased obesity and associated chronic disease follow.

1.We need to take a new look at current food system policies and the Western diet and                             develop a healthful diet while minimizing calorie consumption, salt intake and                                     avoiding excessive protein intake. (The plant-based diet appears to have                                     substantial support.)

2. Deemphasize the importance of higher birth weight, rapid growth and attaining taller height.

3. Emphasize education in good nutrition.

4. Establish clinics for new mothers and young children to teach portion control and healthful                         nutrition. Student participation in preparing healthful meals would also help change                         current nutrition problems.

5. Increase taxes on junk and other undesirable food. Healthful food should be cheaper than             unhealthful food.

6. Shift food subsidies to healthful, low calorie, and plant-based foods.

7. Reward normal weight children with special trips and awards.

If the recommendations seem draconian, they are. Failure to take strong and early action will increase our already bloated deficit. In the coming decades, we are looking at increased health costs of trillions of dollars a year. We can’t afford a moderate program that will require decades to implement.

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