The study evaluated more than 294,000 British residents, the majority of whom were women over 60. Researchers examined links between vitamin D levels and risks of dementia and stroke, using blood testing on all participants and neuroimaging techniques on almost 34,000. A normal amount of vitamin D in the blood is at least 50 nanomoles per litre (nmol/L), while a deficiency is less than 25 nmol/L.
In the 11 years that followed, low vitamin D levels were associated with an increased risk of both dementia and stroke. This observational study revealed that those with low vitamin D levels have a 54% increased likelihood of acquiring dementia than those with normal levels. Even if you have a low vitamin D blood level, these data do not suggest that taking additional vitamin D can prevent dementia or stroke.
If you are concerned about your vitamin D levels, consult your doctor.
