Do you know the “sunshine vitamin”, vitamin D? Your body naturally produces vitamin D when exposed to direct sunlight.
Indeed, sunlight is the main source of vitamin D. The body's ability to synthesize this vitamin depends on the person, their age, their pigmentation, habit and exposure to the sun.
However, exposing yourself to the sun carries many risks for your health: skin cancer, dehydration, burning, fatigue... This is why it is preferable to obtain vitamin D through nutrition from food or supplements.
It is estimated on average that at the end of winter between 40% and 50% of French people have vitamin D deficiencies, but interest in vitamin D and its role in our overall health is increasing. Vitamin D affects many bodily functions, such as bone health. Lack of vitamin D often leads to muscle weakness, fatigue and depressed mood. Studies also suggest that low levels of vitamin D may be a risk factor for autoimmune diseases.
What is the recommended daily dose of vitamin D?
The recommended vitamin D intake value is 15 micrograms per day. You should know that the vitamin D content is often indicated as a percentage on the nutritional label of food packaging. This tells you how much vitamin D intake per day the food will provide.
Why is vitamin D important and what are its functions?
Vitamin D has several important functions. The most vital are regulating the absorption of calcium and phosphorus and facilitating the functioning of the immune system. Getting enough vitamin D is important for the growth and development of bones and teeth, as well as increased resistance to certain diseases.
Vitamin D is necessary for the absorption of calcium in your body. This plays a key role in maintaining bone strength and skeletal integrity. Getting enough vitamin D and calcium is essential for maintaining bone health and protecting against disorders like osteoporosis.
- Reduce the risk of multiple sclerosis.
- Reduce the risk of heart disease. Low levels of vitamin D have been linked to an increased risk of heart diseases such as hypertension, heart failure and stroke.
- Reduce the risk of serious illnesses. Although studies are mixed, low levels of vitamin D contribute to acute respiratory distress syndrome.
- Support immune health. People who do not have adequate levels of vitamin D may be at increased risk of infections and autoimmune diseases.
Research has shown that vitamin D may play an important role in regulating mood and reducing the risk of depression. Other studies have identified low levels of vitamin D as a risk factor for more severe symptoms of fibromyalgia, anxiety and depression.
What are the symptoms of vitamin D deficiency?
Symptoms of vitamin D deficiency in adults may include:
- fatigue, aches and pains
- severe bone or muscle pain or weakness
- stress fractures, especially in the legs, pelvis and hips
Vitamin D deficiency is easily diagnosed by performing a simple blood test. If you have a deficiency, your doctor will probably recommend that you take supplements and depending on the deficiency will order x-rays to check the strength of your bones. You should also make sure you get vitamin D through sunlight and the foods you eat.
What foods contain vitamin D?
Discover the list of foods rich in vitamin D:
Cod liver oil.
It is the food richest in vitamin D with 54.3 µg per 100 g. It has been used for many years to treat vitamin D deficiency. It has also been used in the treatment of rickets, psoriasis and tuberculosis.
It is also very rich in vitamin A, with 150% of your daily value in just one teaspoon (4.9 ml). Vitamin A can be toxic in large quantities. The safe upper limit for vitamin A is 3,000 mcg. Just one teaspoon (4.9 ml) contains 1,350 mcg of vitamin A. So make sure you don't exceed the upper limit with cod liver oil or any other vitamin A supplement.
Additionally, this oil is rich in omega-3 fatty acids. Omega-3s may play a role in heart health and reduce inflammation in the body. Along with fatty fish, cod liver oil is another source of these fatty acids. If you don't eat fish, it can be difficult to get enough omega-3 in your diet.
The salmon.
It is an oily fish and an excellent source of vitamin D.
A 100 gram serving contains between 6 and 23 mcg of vitamin D.
Whether wild or farmed can make a big difference in vitamin D content. On average, wild salmon contains more vitamin D. The amount of vitamin D varies depending on where the salmon is caught and the period of the year. If you don't like that, you can opt for trout.
Herring.
Herring or mackerel are eaten around the world and are among foods rich in vitamin D. They are often smoked or marinated. Herring in particular is an excellent source of vitamin D with 22µg per 100g.
Sardines.
For sardines, you need 12.3 µg per 100g of grilled sardines and 10.8 µg/100g of sardines in oil.
Canned tuna.
Many people enjoy it canned because of its flavor and easy storage methods. It's usually cheaper than buying fresh fish.
Raw tuna is also a good source of vitamin D with 7.2 µg/100 g, and 6.1 µg/100 g for its natural canned version.
Be careful though, it often contains mercury which is a heavy metal present. The amount of mercury depends on the type of fish. Over time, methylmercury can build up in your body. In some cases, this can lead to serious health problems.
Egg yolk.
Whole eggs are another good source, as well as a wonderfully nutritious food. Most of an egg's protein is found in the white, and the fat, vitamins, and minerals are found primarily in the yolk.
The yolk of a large egg contains 3.2µg of vitamin D.
Choosing eggs from chickens raised outdoors or marketed as vitamin D-rich or other foods can be a great way to meet your daily needs.
Mushrooms.
Besides fortified products, mushrooms are the only sufficient non-animal source of vitamin D.
Like humans, they can synthesize vitamin D when exposed to UV light. However, they produce vitamin D2, while animals produce vitamin D3. Although vitamin D2 helps increase vitamin D blood levels, it may not be as effective as vitamin D3.
Some wild mushrooms are excellent sources of vitamin D2 due to their exposure to UV rays, such as morels for example. In stores they have often been grown in the dark and contain very little D2. But may have been treated with ultraviolet (UV) light to increase their vitamin D content.
Chanterelles contain 5.3 µp per 100 grams, morels follow with 5.1 µp/100 g. As for shiitake mushrooms: 3.9 µp/100 grams.
Dark chocolate.
When it contains at least 40% cocoa, chocolate is one of the foods rich in vitamin D. Dark chocolate contains on average 5 µg of vitamin D per 100g.
