Recently, a study came out saying that after the growing prominence of agriculture, a gene increased in frequency which controls the amount of sugar in the blood. Makes sense, right?

Yet, this study questions how that could be the case if such old farming cultures such as India and China still have such a problem with diabetes.

See:
https://ourworldindata.org/grapher/r...ity-prevalence

Yet, the Middle East is an old farming area, as are parts of southern Europe. So, what gives?