A vitamin D deficiency is associated with more and more complaints. In a long-term study, American researchers have investigated the connection between vitamin D deficiency and later dementia. They found that a lack of vitamin D can significantly increase the likelihood of developing dementia in the course of life. The right supply of vitamin D is therefore of the utmost importance until old age.
Older people at risk of vitamin D deficiency
Strictly speaking, vitamin D is not a vitamin at all, because this substance does not have to be ingested with food – like a vitamin – the body can produce it itself.
The body produces the precursors of vitamin D itself. In order to be able to process them into vitamin D, it needs sunlight.
This is also the reason why older people in particular often have too little vitamin D in their bodies. As they get older, they leave the house less and less and avoid the sun outside.
This is fatal, however, as Thomas J. Littlejohns and his colleagues at the American Academy of Neurology have found.
Vitamin D deficiency associated with dementia
The scientists examined serum samples from the years 1993 to 1995 from a total of 1,658 study participants for their content of 25-hydroxyvitamin D – a precursor of vitamin D that is produced in the body and then processed into vitamin D.
In the years that followed, they tested the patients for dementia symptoms – following the diagnostic guidelines of two organizations dedicated to Alzheimer’s disease and other neurological disorders (National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer’s Disease and Related Disorders Association).
It turned out that 171 study participants developed dementia in the course of the study, 102 of them from Alzheimer’s.
The scientists compared these diagnoses with the blood values found.
It was found that the likelihood of developing dementia increased with falling vitamin D levels.
Moderate 25-hydroxyvitamin D deficiency was 1.53 times greater risk of dementia than healthy vitamin D levels. In the case of severe vitamin D deficiency, the risk was even 2.25 times greater.
Scientists have determined separate values for Alzheimer’s disease. Thus, a moderate serum 25-hydroxyvitamin D deficiency increases the risk of Alzheimer’s disease by a factor of 1.69, and a severe deficiency increases it by a factor of 2.22.
The result of the study is clear: a lack of vitamin D increases the risk of dementia enormously.
How to prevent it?
A sufficiently high vitamin D level is therefore of essential importance for human health. Nevertheless, from the point of view of conventional medicine, it is rather unusual to supplement vitamin D, i.e. to take it from food supplements, which is why doctors rarely draw attention to this prevention option.
As already mentioned, the body does not depend on vitamin D from food but can produce it itself with the help of sunlight. So the most important thing is to stay in the sun regularly to get enough UV radiation.
In the summer months, ten minutes a day (at midday) is enough for light-skin types to cover their needs. Darker-skinned people should spend at least 15 to 30 minutes in the sun every day.
In winter, however, the UVB rays required for vitamin D formation do not reach the earth to the required extent – at least not in central and northern Europe. The body can therefore not produce vitamin D in the winter months and has to draw on its own vitamin D stores.
However, if the stores could not be replenished in the summer, sooner or later there will be serious deficiencies that can manifest themselves in a variety of symptoms and, as the present study shows, can even contribute to the development of dementia in older people.
Food does not provide enough vitamin D
Unfortunately, food containing vitamin D is rare. Avocados, for example, contain vitamin D from mushrooms. However, you would have to eat a relatively large amount of both foods every day in order to even come close to covering your daily vitamin D requirement.
For healthy vitamin D levels, adults should consume 20 micrograms of vitamin D (800 IU) with food, according to official sources. However, 150 g of cultivated mushrooms provide just 3 micrograms of vitamin D, and 150 g of avocados only 5 micrograms of vitamin D.
If you don’t soak up any sun at all, the daily requirement for vitamin D increases to more than 100 micrograms (4,000 IU), which can hardly be covered with food.
The vitamin D level can be measured very easily by the doctor (as mentioned above, 25-hydroxy-vitamin D is measured in the serum). Based on the personal starting values, you then ensure regular sunbathing or supplement with the individually appropriate dose of vitamin D in the form of a high-quality dietary supplement.