FOXO3—what a gene: Men who get a "protective" version of it will experience a number of longevity-related upsides: It contributes to regulating insulin, suppressing tumors, and protecting cells from oxidative stress. But it's also likely to make them short. Such is the conclusion of a study of roughly 8,000 Japanese-American men in Hawaii. These men, born between 1900 and 1919, were split into two groups (5-foot-2 and shorter, and 5-foot-4 and taller) and tracked for more than 40 years beginning in 1965, reports Popular Science. "This study shows for the first time that body size is linked to this gene," says researcher Bradley Willcox. "We knew that in animal models of aging. We did not know that in humans." About 250 of the study's subjects are still alive today.
The situation is not entirely straightforward, however. The authors of the study, published in PlosOne, point out that although the gene's role in regulating insulin seems to be its key link to longevity, there are a number of complicating factors, and the hypothesis needs to be tested in a more diverse group of subjects. Willcox was categorical in stating of his test subjects that "the folks that were 5-2 and shorter lived the longest. The taller you got, the shorter you lived." But the study points out that conditions in early childhood, diet, and other variables contribute to one's height and health as well. Thus, Willcox advises that "no matter how tall you are," living a healthy lifestyle can help offset a less-than-favorable version of FOXO3. (Another recent study found that short man syndrome is real.)