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[myloginacct]

Okay, now explain how mainland Europe gained on average 3 inches of height in a century, if not for nutrition.

This is a tough nut to crack. For one, height isn't related to just one gene.

Secondly, there's a big association in early childhood health and final height. So it was not only nutrition over the generations, but the fact most kids were being disease and parasite-free.

Bear in mind the study linked here also said height plateaued in countries like Japan, after a big period of growth.

Change in height around the world over 100 years


On Japan:

The pace of growth in height has not been uniform over the past century. The impressive rise in height in Japan stopped in people born after the early 1960s (Figure 6). In South Korea, the flattening began in the cohorts born in the 1980s for men and it may have just begun in women. As a result, South Korean men and women are now taller than their Japanese counterparts. The rise is continuing in other East and Southeast Asian countries like China and Thailand, with Chinese men and women having surpassed the Japanese (but not yet as tall as South Koreans). The rise in adult height also seems to have plateaued in South Asian countries like Bangladesh and India at much lower levels than in East Asia, e.g., 5–10 cm shorter than it did in Japan and South Korea.

So it seems different peoples (genes, for all intents and purposes) have different peak levels.

Considering the tallest people in the world a century ago are also the tallest people in the world nowadays (the Dutch, Montenegrin, Scandinavians), this is clearly the work of nutrition in association with genetics and better early childhood health.

So, again, the claim that height differences among countries is mostly explained by factors other than genetics is bs.

There's a German member of this forum with a 170cm (5'7) dad and a mother around 160cm who grew to 182cm (~6 feet). This would most likely never happen in a couple of Portuguese, Japanese or Peruvian origin. This seems obviously the result of German genetics, the same genetics that allowed them to get such a big height increase over a century.

What can happen now is that if height starts being heavily sxxually selected for in countries where the height has already plateaued, like Japan, then their average height will probably start increasing little by little, as they'll be selecting for the genes with taller height potential.



Now, this is also all my theory based on all that I've read and observed so far. If an actual researcher on this subject is reading my post and wants to call bs on anything that I said, please do. It'd be highly appreciated and enlighten us all.

tl;dr I think different genes have different peak height potentials. Nutrition, genetics, and early childhood health over the generations are the main factors defining height increase and final height.

[Bigpoppapump]

Starting the day off with carbs is not a good way to start the day. Breakfast cereals and other similar foods typically give people a dramatic rise in energy followed by a slump in energy that then makes the body tired and causes cravings for more carb foods. People who eat high carb foods first thing in the morning are generally fat.

Regardless of which stage it is released poor sleep will definitely blunt HGH production and potentially stunt a persons growth during the growth years.

[ivan]

I beg to differ regarding your carb statement. If you eat an oatmeal or similar complex carb this won't create such an issue. Fruit is also ok since it has fiber. And fat people are generally fat because they eat too much fat and simple carbs like pure sugar.

What do you mean by poor sleep? Only total lack of sleep have the potential to literally stunt someone's growth. I unlike you have read enough papers to claim this. If you have any scientific information to back up your claim, I'll be happy to read it.

[myloginacct]

I'm sorry to say but I think I know now for certain that being often sick in your youth and having a low-protein diet will stunt your growth.

This, of course, doesn't mean everyone was actually going to be 6 feet, and just didn't get to that height due to their youth and nutrition. We have had plenty of anecdotal cases here of people with good health during their childhood and high protein diets who still did not become tall. They'd just have been possibly much shorter had everything gone wrong.

[ivan]

If a person is sick all year round maybe. Infections such as diarrhea and helminthiasis are more correlated with stunted growth though. Many people get sick when there is a flu season.

I agree with the diet statement. However, if a person is well fed, even with not necessary high protein diet as long as he isn't starving and have good amount of minerals and vitamins that may no affect growth (at least significantly). When we give examples with poor countries with low protein consumption we have to keep in mind that these people are not nourished, left alone protein fueled.

[myloginacct]

If a person is sick all year round maybe. Infections such as diarrhea and helminthiasis are more correlated with stunted growth though. Many people get sick when there is a flu season.

I agree with the diet statement. However, if a person is well fed, even with not necessary high protein diet as long as he isn't starving and have good amount of minerals and vitamins that may no affect growth (at least significantly). When we give examples with poor countries with low protein consumption we have to keep in mind that these people are not nourished, left alone protein fueled.

The nutrition aspect is something I'd be willing to pay money to know for sure, but I don't think most nutritionists and endocrinologists really know the finer details between diet and height. Sure, nutrition affects height. We know that much.

However, let's imagine monozygotic twins living in developed nations. One is fed a vegan, high-carb, low-protein diet all his life, and the other is fed a high-protein, average Western diet until his growth plates are closed. What difference could we expect in their heights?

[ivan]

However, let's imagine monozygotic twins living in developed nations. One is fed a vegan, high-carb, low-protein diet all his life, and the other is fed a high-protein, average Western diet until his growth plates are closed. What difference could we expect in their heights?

It's hard to conduct such study due to the fact that vegan parents would not feed only one of their kids vegan. However, there are many people nowadays that decide to rise their children vegan. If they are living in a developed nation with access to quality food I think we still may see the effect.
I happen to know such people and their kids are really well fed and quite healthy since their parents are mindful regarding important drawbacks of the diet such as vitamin b12 deficiency and other nutrients. At least for now their height velocity is similar to other well-fed kids.


This is far from well conducted study and it's not for vegans but vegetarians but it shows that well fed children will still reach their peers and may even outgrow them: https://www.ncbi.nlm.nih.gov/pubmed/1855500

[myloginacct]

It's hard to conduct such study due to the fact that vegan parents would not feed only one of their kids vegan. However, there are many people nowadays that decide to rise their children vegan. If they are living in a developed nation with source to quality food I think we still may see the effect.
I happen to know such people and their kids are really well fed and quite healthy since their parents are mindful regarding important drawbacks of the diet such as vitamin b12 deficiency and other nutrients. At least for now their height velocity is similar to other well-fed kids.


This is far from well conducted study and it's not for vegans but vegetarians but it shows that well fed children will still reach their peers and may even outgrow them: https://www.ncbi.nlm.nih.gov/pubmed/1855500

I saw that one before. It had gave me some ease of mind.

I decided to google some more and found these very interesting studies:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3736755/ - This one is a must read for anyone on this forum interested in this subject. Still dissecting it myself.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3275599/ - This one is less related, but still linking it.

[ivan]

I'll check these, thanks.

[myloginacct]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5732171/

Other than this bs quote repeated ad nauseam as gospel truth in these studies, the other parts of the study seem alright: "Taller people live longer." No... They absolutely don't. I don't know why this is repeated so often. The longest living Europeans, and indeed the world, are the short Sardinians, not the tall Dutch... The close contenders are also all much smaller in stature (e.g. Okinawans, Ryukyuans, Nicoyan Costa Ricans).

Study authors: Josep Peñuelas, Ivan A. Janssens, Philippe Ciais, Michael Obersteiner, Tamás Krisztin, Shilong Piao, Jordi Sardans.

[myloginacct]

Graph by Dr. Randal Olson.

It's interesting to note how the height increase did not seem to be affected in Germany, despite, you know, the two world wars, which they both lost and brought economic turmoil. The US, France and Italy all had some drops in median height throughout this time period, though (1820-2013)...

Would also like to see data on Russia.

The last drop in the US is also far less important, as the country got vast amounts of immigrants from shorter ethnic groups.

[myloginacct]

Original page: http://www.randalolson.com/2014/06/23/why-the-dutch-are-so-tall/

[W]

I would say up to 5cm because I have a twin brother who is 4-5cm shorter than me that avoided gym class with a sugar & carb based diet.

[myloginacct]

I would say up to 5cm because I have a twin brother who is 4-5cm shorter than me that avoided gym class with a sugar & carb based diet.

What you described is not enough to stunt height that much, in my current opinion. I'm assuming you are dizygotic twins. Not monozygotic twins. 

If you guys are indeed monozygotic, then, well, pardon my tone, and I'll be eating some socks.

Because height is influenced by nutrition, particular scrutiny for confounding by cumulative nutrition is important. Diet is influenced by genetic factors, and monozygotic twins repeatedly have been shown to be similar in nutritional status (15, 16). These height-dant twins, in the view of their mothers, had similar diets as children. According to the young adult twins themselves, the most sensitive observers of between-twin differences, their food preferences, habits, and levels of obesity were nearly identical at the time of contact and are unlikely to have changed since childhood (15, 25). Thus, the available evidence suggests that the relative frequency of infections may be independently associated with adult height.

If causal, several possible mechanisms could explain the association. Infections during early childhood result in periods of catabolism, diverting calories away from growth (14).

[...]

We report that childhood infection is significantly associated with height differences in monozygotic twins, independent of genetics, socioeconomic status, parental behavior, and available indicators of nutrition. Although the relationship between childhood infections and growth has been studied extensively in developing countries, our results also suggest a relationship between childhood infections and adult height in a generally healthy, economically developed population.

Study Authors: Amie E. Hwang, Thomas M. Mack, Ann S. Hamilton, W. James Gauderman, Leslie Bernstein, Myles G. ckburn, John Zadnick, Kristin A. Rand, John L. Hopper, and Wendy Cozen.

Shorter height at 6, 10, 13, and 18 years of age was more strongly associated with shorter adult height than was weight at each age. Shorter height at age 6 years was most strongly predictive of shorter adult height (odds ratio = 27.4; ratio of exposure-dant twin pairs = 89/3); 41% of the taller and 40% of the shorter twins reported that the disparity in height had appeared before age 6; 58% and 56%, respectively, indicated that it had appeared before the age of 12 years.

The twin with more maternally reported episodes of childhood infection was approximately twice as likely to be the shorter twin (Table 2). This was evident for each measure of illness frequency and persisted after adjustment for birth weight and birth length (Table 2; Web Figure 2). There were no statistically significant differences in the odds ratios among the 5 age categories (χ2 test of heterogeneity not shown).

In a stepwise model, the within-pair difference in febrile illness frequency during the toddler years was the strongest and most significant predictor of adult height difference (data not shown).

The association between more toddler infections and shorter stature was stronger among the subset of pairs differing by more than 1 inch compared with the subset differing by just 1 inch [...]

Because most questions to mothers were related to infections, (e.g., frequency of antibiotic use and febrile illness), and since those with chronic disease had been excluded, infections probably accounted for the majority of reported illnesses. The association was strongest for infections during the toddler years, when the difference in height usually appeared, and was independent of birth length and weight. In this study of monozygotic twins, the association between illness in the early years and adult height was independent of heritable factors, childhood social class, and parental behavior.

This is from a study linked earlier in the thread.

[myloginacct]

If you guys are indeed identical (i.e. monozygotic) twins, then that'd be awesome to know.

[myloginacct]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1720514/pdf/v090p00807.pdf#page=5&zoom=auto,-12,500

Eveleth and Tanner reported that differences in body proportions are genetically controlled and different for European, African, and Oriental populations (Caucasians
have tall stature with long legs, in contrast to Orientals). With better environmental circumstances, relatively longer legs appear in all ethnic groups. In fact, monitoring leg length might even be a better tool for reflection of environmental improvements than height. Abused children, who have relatively short legs, showed a significant recovery of leg length after social interventions.

Authors: A M Fredriks, S van Buuren, W J M van Heel, R H M Dijkman-Neerincx, S P Verloove-Vanhorick, J M Wit

This quote seems to also state and expand on what I've had previously seen stated in this other study:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2872302/

The reason for this is the general principle that those body parts growing the fastest will be most affected by a shortage of nutrients, infection, parasites, physical or emotional trauma, and other adverse conditions. The cephalo-caudal principle of growth as applied to the human species means that the legs, especially the tibia, are growing faster relative to other body segments from birth to age 7 years. Relatively short LL in adolescents and adults, therefore, is likely to be due to adversity during infancy and childhood leading to competition between body segments, such as trunk versus limbs and between organs and limbs.

Authors: Barry Bogin and Maria Inês Varela-Silva

Mind you, the article I'm quoting now (first link) specifically refers to Dutch people. So their definition of "relatively short legs" and its associated numbers and ratios will follow the standard for modern-era Dutch people.