Meeting News

Vitamin D is underestimated, researcher says

ANAHEIM, Calif. – John J. Cannell, MD, medical director of the Vitamin D Council, illustrated the importance of vitamin D and lack of a consensus on its significance across all areas of medicine here at the Ocular Nutrition Society meeting.

The society held its meeting prior to the American Academy of Optometry meeting.

“[Cannell] is interested in the big picture, what is going on around him and how we can improve the lives of everyone around us,” Stuart Richer, president of the Ocular Nutrition Society, said in the introduction.

Cannell John
John J. Cannell

Vitamin D is a steroid hormone that is made by a cholesterol molecule and works by going to the genes and regulating them, Cannell explained.

“There are about 3,000 vitamin D receptors in your body making proteins because a vitamin D receptor told them to, or not making them because that’s what they’ve been told,” Cannell said.

Vitamin D is a hormone just like testosterone or cortisol, he said.

“You have to grasp the seriousness of this: Steroid hormones do a lot of things. They help with brain and eye health and athletic performance and many other processes, and it’s an important thing to know,” he continued.

Vitamin D steroid compounds are essential for the maintenance of normal calcium. One’s body maintains calcium levels at strict ranges, he said.

“It is truly hard to find a tissue in the body where vitamin D is not a part of the function,” Cannell added.

Vitamin D receptors are present all over the eye, according to Cannell. With more research, age-related cataracts, dry eye syndrome and childhood myopia management could be revolutionized.

Autism may be impacted as well.

Children with autism have lower vitamin D levels then those without autism. Children with autism have lower vitamin D levels than their identical twin, he said.

In a randomized control trial involving 80 children with autism, researchers prescribed 450 IU/kg of weight. Half the children lost the diagnosis of autism on the Childhood Autism Rating Scale, and 25% of the children were improved but still on the scale, he explained.

“It needs to be present in food to prevent this. You can’t get mothers all around the world to take 6,000 IU a day. It just won’t happen. Grains, condiments, lima beans, it can be in anything and can be totally tasteless,” he said.

For normal adults, he recommends taking 5,000 IU daily of vitamin D.

He recommends 6,000 IU/daily for pregnant and breastfeeding women. For infants, he recommended 1,000 IU for the first year and 1,000 IU for every 25 pounds after that.

No one has overdosed on vitamin D, he added. – by Abigail Sutton


Cannell JJ. Vitamin D and eye health. Presented at: Ocular Nutrition Society annual meeting; November 8, 2016; Anaheim, Calif.

Disclosure: Cannell founded the 501(c)(3) nonprofit the Vitamin D Council and is the author of Athlete’s Edge: Faster, Quicker, Stronger with Vitamin D and numerous peer-reviewed papers.


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