Low levels of vitamin D in the blood stream have been linked to a variety of chronic health problems including arthritis, diabetes, heart disease, infection, kidney disease, osteoporosis, stroke and cancer. Now add dementia to that list.

A study in the Journal of the American Geriatrics Society followed almost 3,000 older adults for four years. They were tested for cognitive function at the beginning and end of the study. Vitamin D levels were also measured.

The investigators found an association between low vitamin D levels and a drop in cognitive performance. The scientists caution that their study does not prove cause and effect. To do that will require some different types of studies.

The value of vitamin D is becoming so clear, however, that it makes sense to have levels assessed and take steps to bring them into a normal range if they are low. For many older people, sun exposure is impractical or may be too hazardous given pre-existing skin conditions. In that case, the answer may lie in supplements.

[Journal of the American Geriatrics Society, April 15, 2014]

Those who would like to learn more about vitamin D and how to assess blood levels may be interested in our 8-page Guide to Vitamin D Deficiency. The guide also describes what sorts of supplements may be useful.

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  1. Gail S.

    I am interested in the level of Vitamin D that is considered normal. What type of supplement should be taken – important to know at age 71 – trying not too get too much sunshine………

  2. Helen M

    I have read that you can take up to 10000 units of D3 daily without toxicity. If you google upper safety limits of D, you will probably be taken to the cite.
    Speaking for myself only: I began with 1000 units and some sun several years ago. Last levels, while taking 5000 units a day, and less sun, were 49. Since I would like them higher, I have added another 5000 three times a week.
    Getting out in the sun is difficult here. Winter is grey, virtually no sun. Summer is broiling, most days over 95. I try to get out in the more temperate times of the year for 15 to 30 minutes, usually sitting and doing some work. Walking in the sun would be best; however, no longer possible.

  3. Soozi

    I wonder if high levels of D relate to people who are athletic and out in the sunshine. That would mean they are active, exercise and have muscle development. If all that good health is not the same for people who take supplements, perhaps it’s really an exercise effect.
    I live with a person who mows the lawn, is a sports photographer and never touches mushrooms, salmon, fortified foods or vitamins. He is super active and his D levels are normal. My level is low. I take D supplements and seems obvious that he is much healthier than I am… in my small sample of two.
    Just a thought… any comments on that?

  4. ou.alum

    I have raised my D from 17 to 31. I would like to know safe amount of daily supplement.

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