A person needs ten micrograms of vitamin D per day to get and keep healthy bones, teeth and muscles, according to the Public Health Service in England (Public Health England). Vitamin D is made by our body itself under the influence of sunlight. In the summer months and often in the spring, many people get those 10 micrograms, but in the winter and autumn we have to get most of our vitamin D from our diet and that is not that simple.
Reason for advice
The PHE National Diet and Nutrition survey was conducted between 2008 and 2012 and found that 23 percent of adults aged 19 to 64, 21 percent of seniors and 22 percent of young people aged 11 to 18 had low had levels of vitamin D in their blood. So low that there is an increased risk of vitamin D insufficiency. We getvitamin D not only from sunlight, but also through our diet, especially from oily fish, meat, butter and eggs. If we rely solely on our diet, we do not get enough vitamin D. We depend on the sun for 90 percent of our daily amount of vitamin D.
Symptoms of vitamin D insufficiency
If you suffer from vitamin D insufficiency, you may experience the following symptoms:
- Listlessness, lethargy, lack of energy
- Bleeding gums
- Cramps and pains in the muscles
- Weak bones
- But also psychological complaints such as depressive complaints and/or anxiety attacks
There are several studies that show the link between a mild seasonal deficiency (insufficiency) of vitamin D and certain forms of cancer. This concerns prostate cancer, breast cancer and colon cancer.Not many people have a real vitamin D deficiency. This used to happen more often. In children, a deficiency leads to skeletal abnormalities, also called English disease or Rickets. In the elderly, osteoporosis occurs due to a vitamin D deficiency. Particularly in women over the age of 50, depressive symptoms regularly occur as a result of a mild vitamin D deficiency.
Vitamin D and strong bones and teeth
Vitamin D ensures that calcium and phosphates from food are absorbed into the body as building blocks for strong teeth and bones during growth. In old age, sufficient vitamin D helps to repair bone cells and prevent osteoporosis.
Vitamin D and immune system
Vitamin D is needed in the process that produces a natural antibiotic (cathelicidin), which ensures better resistance and inactivates and removes bacteria. This cathelidicin prevents inflammation in the body, which reduces the risk of certain types of cancer. In addition, innate immunity is improved by the presence of vitamin D. Under the influence of sufficient vitamin D, more antimicrobial peptides, cytokines, monocytes and macrophages are produced, which are necessary for a good immune system.
In the sun
To get enough vitamin D from the sun, you should be outside for fifteen minutes in clear weather every day between 11:00 am and 3:00 pm when the sun is at its strongest. In cloudy weather half an hour. People with dark skin color need more sunlight to produce vitamin D and older people (over 50) also need to spend more time outside to get the required amount of vitamin D.In winter and autumn, the body cannot produce vitamin D under the influence of the Dutch sun. Here in the Netherlands, the sun is only strong enough in the period between the end of March and the beginning of September to encourage the body to produce vitamin D.
Vitamin D all year round
The further north you go, the more common depression, diabetes and cognitive decline are in later life. There are strong suspicions that a vitamin D deficiency plays a role in this.
Diabetes
Type 1 diabetes is caused by a fault in the immune system. The body destroys its own insulin-producing cells and it is suspected that a low vitamin D level in the body plays a role in this. It also appears to be the case that a low vitamin D level causes an increased glucose level in the blood and increases the risk of type 2 diabetes.
Cognitive decline
Vitamin D lowers the serotonin level in the blood, causing you to suffer from feelings of depression. A serotonin deficiency also plays a role in cognitive decline. Research from 2015 by the Alzheimer’s Disease Center in Sacramento (USA) shows that cognitive decline in dementia patients occurs two to three times faster if there is a vitamin D deficiency. There were already suspicions that there was a relationship between psychological and cognitive complaints and vitamin D deficiency, because previous research showed that schizophrenia and autism are almost always accompanied by vitamin D deficiencies and that vitamin D deficiency also causes depression and mood disorders.
Cancer
A vitamin D deficiency is also associated with an increased risk of breast cancer, prostate cancer and colon cancer. The relationship between these is not yet completely clear.The health service’s advice is that everyone should take vitamin D in winter and autumn. Vitamin D all year round is recommended for people over 50, children up to four years old, people with dark skin, people who rarely go outside between 11:00 AM and 3:00 PM and people with psychological vulnerability. For top athletes, a vitamin D deficiency can negatively affect their sports performance, so top athletes are also advised to take vitamin D all year round.
Too much vitamin D
Under normal circumstances it is impossible to get too much vitamin D. This is only possible if you have exceeded the maximum dose of nutritional supplements for a longer period of time. When this happens, calcium deposits can form in the body. So never take more than the prescribed dose.