Vitamin D: Everything you need to know about the sunshine vitamin

Everyone is talking about the sunshine vitamin D. It is essential for maintaining healthy bones and is particularly important for women who have an increased risk of developing osteoporosis. The question arises: Does taking additional vitamin D make sense? To get to the bottom of this question, it is important to look at what functions vitamin D has in our body. Why do we need vitamin D? Vitamin D regulates calcium and phosphate levels in the body. Intestinal calcium absorption is promoted and reabsorption in the kidneys is increased, which mineralizes our bones and keeps their structure stable and healthy. An optimal supply of vitamin D prevents fractures and bone damage and minimizes the risk of developing osteoporosis. But what happens if you have a vitamin D deficiency? A vitamin D deficiency means that the body is less able to absorb calcium. The result: a decrease in bone density, which means that the bones become brittle and the risk of fractures increases. In addition, muscle strength can also decrease, which can lead to an increased number of falls. This is a spiral that additional vitamin D intake can help to break. For example, vitamin D supplementation in women suffering from osteoporosis leads to an increase in calcium absorption of up to 65%. How do we absorb vitamin D? Vitamin D is not called the sunshine vitamin for nothing. We cover most of our needs through UVB radiation that hits our skin, which helps our body produce the active hormone calcitriol in the liver and kidneys. Only a very small part of our vitamin D needs can be obtained through food, as it is only found in some types of sea fish, oysters, egg yolks and liver. How much vitamin D does the body need? Current recommendations state that the 25-hydroxyvitamin D3 serum level should be at least 30 ng/ml (75 nmol/l). How does a deficiency arise and who is affected by it? Unfortunately, vitamin D deficiency is common and the causes are varied. Even people who spend a lot of time outdoors can be affected. The intensity of sunlight, clothing, creams with UV protection and even the weather all affect vitamin absorption. Age is also an important factor, as the body's ability to produce vitamin D decreases over the course of life. This means that an estimated half of all postmenopausal osteoporosis patients suffer from a vitamin D deficiency - regardless of where on earth they live! Vitamin D administration for osteoporosis For this reason in particular, accompanying therapy with vitamin D, ideally in combination with calcium, is an important building block for successful osteoporosis treatment. Studies have shown that this can minimize the risk of fractures by an average of 20%. In the area of the vertebrae, wrist and forearm joints and hips, the risk can even be reduced by up to 30%. It is therefore all the more surprising that recent surveys have shown that only one in five women in Europe receives vitamin D as part of their osteoporosis treatment. How can you prevent a deficiency? According to current recommendations, anyone who wants to prevent vitamin D deficiency and especially osteoporosis should take 400-1,000 IU of vitamin D daily. Side effects due to an overdose are not to be expected. Long-term studies have shown that even a very high dosage (up to 4,000 IU per day) has no negative effects on calcium levels in the blood and urine.