Comment by v8xi | Hacker News Reader

Comment by v8xi | Hacker News Reader

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That's what they seem to hint at in the final sentence.

> "Suggesting to the study authors that city life in Milan has provided a stable environment for thousands of years"

This does throw a wrench in prevailing thought that improved childhood nutrition is leading to taller people. I would guess that, when it comes to changes in stature, environment/nutrition are more cataclysmic effectors while genetics vis-a-vis sexual preferences play a more sustained role in shaping it. i.e. in a stable environment you would expect change mostly to be effected by the cultural preference of taller/shorter people.

On cataclysmic effectors - one really interesting study I think back on often[1] is a serendipitous survey of island lizards hind-leg lengths before and after a major hurricane season. Basically, they found that over the course of one year, there was a 6% reduction in the populations leg lengths due to, they claim, the taller ones being unable to hold onto trees during the storms.

[1] https://www.smithsonianmag.com/science-nature/lizards-with-b...

In stark contrast to Milan. Koreans were steadily around 5'3"/4'10" in the Joseon era, 15th to 19th century, then grew 6 inches in the past century. Improved childhood nutrition might not lead to a taller population, but poor childhood nutrition definitely leads to shorter adult height.

https://www.koreaherald.com/view.php?ud=20120131000667

Ehh you can't draw that conclusion. North and South Koreans have a 7 height difference of 6 inches. What's more likely happening here is that the Milanese diet has no changed since the Roman Era. Or has to changed very little in meaningful ways, i.e. more nutritious meals.

> the Milanese diet has no changed since the Roman Era. Or has to changed very little in meaningful ways, i.e. more nutritious meals.

Interesting to note that potatoes, tomatoes, and pasta were not present in their diet during Roman times.

Those products are more southern Italian cusine. Northern is typified by cheese, butter, lard, and corn/rice.

True. But the average Korean was also around and often under 4 feet tall up until the 1950s. So yeah. Now depending where you are they average 6 feet. And well, they haven't been ethnically replaced. So unless the Koreans have a magic gene that has made them gain 2 feet in height. No, it's definitely their diet.

You have to provide a credible reference for a ridiculous claim like this. Cursory search says Korean’s average height has grown about 6 inches in a century. Two feet or 50% taller might as be a new subspecies.

Here's an article from a credible source on Korean height. https://www.vox.com/videos/2023/2/23/23611947/world-south-ko...

From that article:

> For example, the average South Korean woman was about 4-foot-7 ...

That's closer to 5 feet than 4 feet. And 4 foot 7 is kind of hard pressed to be "around 4 feet", which most people would read as "around 4 foot 0".

Maybe Korea's issue (as well as other East Asian countries) issue with a rice-based diet (especially white rice) in the absence of modern levels of consumption of meat or other animal-derived food. While bread (especially whole bread) has some level of protein in and of itself, and Italians have also had cheese and milk available at least some of the time, trying to survive off of a diet of rice and vegetables must be particularly unsuited to growing to your genetic potential. My impression of Korean food is that it would be quite unsatisfying from a nutritional standpoint without the meat, whereas Indian and even Chinese food seem to be a little more nutritious.

> without the meat, whereas Indian and even Chinese food seem to be a little more nutritious.

> even

Interesting word to describe the cuisine with arguably the richest history of vegetarian dishes/diet.

Hmm, I would consider Indian to have the richer history of vegetarian dishes, hence why I used "even Chinese". Moreover, Indian cuisine uses cheese and butter, unlike Chinese cuisine

> This does throw a wrench in prevailing thought that improved childhood nutrition is leading to taller people.

It absolutely can lead to taller people if the genetic height potential had been suppressed by poor childhood nutrition. You see this in stark form in developing countries where heights are rising rapidly (sometimes nearly a foot in one generation in individual cases). It's not only nutrition - it's access to more modern medicine, including vaccines and treatments, and improved sanitation that prevent childhood diseases that stunted people in the past.

If a population is already on average at its maximum genetic height potential, however, improved nutrition and healthcare isn't going to change height much.

Anecdotally, in the Milan area in every single generation of people I know, the males are taller than both parents and the females are often taller than their mother.

How much taller? People do shrink in height a few centimeters starting at age 40.

10 cm or more. That's 4 inches. That started with boomers many years ago.

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