During this pandemic, vitamin D has taken center stage, partly for its ability to strengthen the immune system. While its link to sun exposure is generally well known, its exact effects on the body are often less clear. What is vitamin D? How does it affect our bodies? How can we ensure we get enough?
What is vitamin D?
The word “vitamin” actually refers to an organic substance (i.e., made from carbon), necessary in small quantities to ensure the proper functioning of a living being. Indeed, the latter cannot synthesize it by itself (or not in sufficient quantity)! A vitamin is, therefore, an element whose intake is essential for the proper functioning of the body. Vitamin D is one of the fat-soluble vitamins (it is soluble in lipids), just like vitamins A, E, and K.
In humans, vitamin D has, as we will see later, two origins:
- Part of vitamin D is endogenous, meaning it is produced directly by our skin when we expose ourselves to the sun.
- The other part is exogenous, meaning it is provided by food, notably fish and certain mushrooms
Vitamin D in the body: its life cycle
Vitamin D will go through several phases before becoming “active” (i.e., able to act on the body).
Step 1: Vitamin D on the plate
The vitamin D cycle can begin with its intake through food, in the form of:
- of vitamin “D2” (ergocalciferol) in plants
- of vitamin “D3” (cholecalciferol) in animal products.
The skin can also produce vitamin D3 directly from sun exposure!
Step 2: its transformation into calcidiol
Regardless of its origin, vitamin D (then inactive) is first transported to the liver, where it undergoes a first transformation into “calcidiol”. At this stage, vitamin D is still inactive but can be easily measured in the blood (this is the form that is measured in cases of suspected vitamin D deficiency).
Step 3: Its transformation into calcitriol
Vitamin D finally undergoes a final transformation in the kidney, where it becomes “calcitriol.” Calcitriol is a true hormone active in the body. It finely regulates calcium balance!
Even if you have sufficient vitamin D intake, the initially inactive vitamin must become active to act on the body. A functioning liver and kidneys are therefore essential to benefit from the effects of vitamin D!
The benefits of vitamin D on the body
Vitamin D appears to play a role in many areas of the body. Some of its effects are certain and documented, while others are still being studied to obtain real scientific evidence. Among the areas influenced by vitamin D, we find:
Bone formation and maintenance of bone capital
Calcitriol (vitamin D, activated by the liver and then the kidneys) helps increase calcium and phosphorus levels in the blood. These elements are essential for bone formation (vitamin D deficiency is still the cause of rickets today in certain regions of the world). Vitamin D also helps maintain bone mass throughout life, and thus fights against osteoporosis (age-related weakening of bones)!
Effects on the immune system
Vitamin D tends to strengthen the immune system. It could therefore be a protective factor against certain autoimmune diseases as well as certain infectious diseases. Some recent studies— currently offering a low level of evidence —suggest a protective role for vitamin D for people with COVID-19 (reducing the pulmonary inflammatory response).Â
Vitamin D also has possible protective effects against cancer and provides cardiovascular protection.
Where can you find Vitamin D?
First of all, a good part of the vitamin D we need is produced by the body itself! Indeed, the skin is a large producer. It is under the action of the sun’s rays (type B ultraviolet) that it will, from cholesterol, produce the famous vitamin D. Thus, sun exposure of at least 15 to 30 minutes twice a week helps, in the majority of cases, to meet the body’s needs. This does not prevent you from protecting yourself with creams that are good for the skin (and for the planet) 🙂
In summer, the body will therefore stock up on vitamin D and then store it in the liver, muscles, and body fat, in order to be able to use it in winter, when there is less sunshine.
Additionally, some foods are richer in vitamin D than others. However, their number is limited, and they are not very “common” foods. We find:
- cod liver oil, in first position
- Oily fish such as herring, mackerel, sardines, anchovies, trout, etc.
Many other foods contain vitamin D, but the amount is negligible.
Some tips to strengthen your immune system đź’Ş
On television, in pharmacies, at the supermarket… There are many places where you can find products that are supposed to boost your immunity in preparation for winter illnesses. Unfortunately, most of the products on offer probably don’t have a significant effect on the effectiveness of your immune system, and can even cause harmful effects if used incorrectly or in excessive quantities.
Indeed, it is not recommended to take dietary supplements if there is no deficiency found. A few simple rules are enough to be healthier, and therefore to have a potentially more effective immune system:
- Eat healthy and balanced meals to avoid deficiencies and excessive intake
- Have good sleep hygiene (get long enough, unbroken nights)
- Practice regular physical activity
- No smoking, consume alcohol in moderation
- Get vaccinated (which has a direct effect on the immune system)
- Wash your hands regularly, when you get home, and before cooking (to prevent the transmission of diseases)
If you want to boost your immune system in a 100% natural way, we invite you to read this article on essential oils and vitamins!
Vitamin D is an essential element for our health. Its deficiency leads in particular to bone pathologies, requiring supplementation. Outside of these deficiency situations, sunshine greatly helps, in the majority of cases, to meet our needs, and therefore to keep us in good shape. In the case of the COVID-19 pandemic, it has been suggested ( but without formal proof ) that this vitamin could have a positive effect on the consequences of the disease. Whatever happens, there is no miracle solution: the best way to have good immunity remains to have a healthy lifestyle to stay healthy!
+ There are no comments
Add yours