Ask any health nut what supplements you should be taking every day and vitamin D will surely be on the list. Low levels of it have been linked to increased rates of just about everything you want to avoid: diabetes, allergies, cancer, heart disease, mental illness and death.
But a new study published in the Canadian Medical Association Journal says low levels of vitamin D may be associated with something many of us want: longevity.
Dutch researchers looked at 380 families with at least two siblings over 90 years old, their offspring and their offspring's partners, who could help researchers understand the influence of genetics compared with that of environmental factors, since spouses would share the latter but not the former.
Researchers measured vitamin D levels and examined the influence of genetic variation in a handful of genes linked to vitamin D levels.
After controlling for age, sex, body mass index, time of year, kidney function and supplement use, which can all influence a person's vitamin D levels, researchers discovered that low levels of vitamin D may be a good thing, at least when it comes to living longer.
"We found that familial longevity was associated with lower levels of vitamin D and a lower frequency of allelic variation in the CYP2R1 gene, which was associated with higher levels of vitamin D," Dr. Diana van Heemst, one of the study's authors, said in a release.
Specifically, researchers found that offspring of people in their 90s with at least one nonagenarian sibling had lower levels of vitamin D than people in the control group "independent of possible confounding factors." Those same offspring also had less of a genetic variant that predisposes people to high levels of vitamin D.
Although low levels of vitamin D have been associated with so many ills, it is not known if low levels cause them or are instead a consequence of such conditions.
The study's authors say their findings clearly support a connection between low levels of vitamin D and familial longevity, although they also noted that more research needs to be done in order to better understand that link.