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Indemnity4 t1_iw43kb8 wrote

The greatest example we have is a Longitudinal Aging Study Amsterdam. At the end of WW2, the Nazis starved the Dutch city of Amsterdam for ~ 2 years.

Women who were starving when pregnant gave birth to children who when they reached adult height were short than expected by ~4.5cm.

Second generation children (grandchildren of the starving pregnant woman) were also shorter than expected, by ~4 cm.

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tt1702y t1_iw8fxli wrote

Are we talking about extreme starvation like famine and starving for most of childhood?

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Indemnity4 t1_iw997em wrote

Dutch Famine of 1944-45 was starving-to-death starvation. 20,000 people died.

The legacy is historically and scientifically interesting because the Netherlands is a modern, wealthy, highly educated population with excellent health care. The entire famine was extremely well documented, which makes later followups very complete.

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tt1702y t1_iwa1kif wrote

So if I was to get adequate nutrition living in a third world country and I lived good, I would reach full potential of height right?

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Indemnity4 t1_iwa7d69 wrote

Too difficult to diagnose at a distance. At a minimum, way more complicated.

There is good evidence that about 80% of your adult height is determined by genetics, with the remaining 20% due to environmental factors. Mostly nutrition and disease.

But in poor African countries or other poor areas of the world, only approximately 65% is determined by genetics. There is something different in poor countries besides just genetics or simple environmental factors like nutrition.

The Dutch Famine study is the evidence of something that affects your genetics via something called epigenetics. If your mother was starving while pregnant, you would be shorter than a sibling born before the famine. Plus your children would also be shorter than your nieces and nephews. But then 4th generation is back to normal.

Overall: you need multigenerational optimum nutrition/disease conditions to reach maximum potential based on your genetics.

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tt1702y t1_iwacepl wrote

We are talking about extreme malnutrition am I right? For example starving to death for most of childhood and prenatal growth like the dutch famine where many died from starvation am I right? Therefore having adequate nutrition from parents, you would be good right?

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Indemnity4 t1_iwaeblz wrote

As a rough rule, it's about averages. Rich people with lots of resources will be taller and reach a plateau within their society, compared to poorer people with fewer resources. But there are always exceptions in each group.

Diseases or childhood illness may prevents you obtaining maximum height.

Nutrition is more than just calories. Ideally you have a varied diet. For instance, you could be really obese from eating sugar but your diet is lacking in protein or a particular vitamin.

The final thing is we can't rule out any effects from your grandparents epigentics, or other random things we cannot predict. Some medications will affect future children.

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