Overdosing on vitamin D supplements is possible and harmful.
A case report in the BMJ:
Vitamin D supplement ‘overdosing’ is possible and harmful, warn doctors
The MEA Comments
Dr Charles Shepherd, Honorary Medical Adviser to the ME Association comments:
This is an important warning about the dangers of overdosing on vitamin supplements.
Although there have been some small research studies reporting minor abnormalities in vitamin status in ME/CFS, there is no firm evidence that vitamin deficiencies are present in people with ME/CFS, or that vitamin supplements are a safe and effective form of treatment for ME/CFS.
There are two exceptions::
Firstly, if someone with ME/CFS is taking a diet that may be restrictive in vitamin content then it would be sensible to take a good multivitamin supplement.
Secondly, we know from both patient evidence and research into vitamin D status in people with ME/CFS that there are some people, especially those at the severe end of the spectrum, who are deficient in vitamin D.
This is not surprising – because vitamin D is produced in the body through the action of sunlight on the skin and lack of exposure to the sun is a well recognised factor in producing vitamin D deficiency.
So, people with ME/CFS who are housebound, or largely housebound, and do not go outdoors, should check with their doctor about their vitamin D status – as any significant deficiency will need to be treated.
And, as the NHS now advises, everyone should consider taking a daily vitamin D supplement throughout the year. With a supplement, the daily requirement is 10 mcg or 400 IU. On a personal basis, I take a vitamin D supplement every day.
NHS guidance on vitamin D supplements can be found via the button below
The MEA information has a leaflet on Vitamin D deficiency and ME/CFS
Vitamin D & Deficiency
Dr Charles Shepherd,
Trustee and Hon. Medical Adviser to the ME Association.
Member of the 2018-2021 NICE Guideline Committee.
Member of the 2002 Independent Working Group on ME/CFS.
