The vitamin D obtained from sun exposure may be a proxy for other beneficial factors associated with being outdoors, rather than a direct benefit of the vitamin D itself.

“the improvements that we see in outcomes in studies with higher people with higher vitamin D levels are a proxy for sun exposure rather than pushing high vitamin D because when we do interventional studies with people and give them a whole bunch of vitamin D we don't see the same effects”

“I do not think it's my personal opinion sort of medical perspective that taking vitamin D is not the same as getting sunlight and that the benefits of sunlight the benefits of sunlight are”

“taking vitamin D is not the same as getting sunlight and that the benefits of sunlight the benefits of sunlight are unique and cannot be mimicked by vitamin D”

“it suggests that either the Sun has unique benefits or the people who are in the Sun more are doing other valuable things”

“I think that the huge confounder is all these people outside are exercising. That's what's been giving them the benefit. It's not the sun per se or the vitamin D per se.”

“the vitamin d that you take supplementally Ain't fixing the problem the vitamin d that's getting fixed in the sun is a proxy for things that are happening good in the sun”

“A lot of the epidemiology that suggests the significant benefits of vitamin D some have speculated that it might be less the vitamin D the higher vitamin D levels in those individuals and more what they're doing to achieve high levels of vitamin D if they're doing it without supplementation namely just being outside and being active”