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Vitamin D

The article in a few key points

Vitamin D is a fat-soluble vitamin essential for immunity, growth and healthy bones, teeth and muscles. It is produced by the body when exposed to the sun.

Among the two forms of vitamin D (D2 of plant origin and D3 of animal origin), vitamin D3 is preferred because it is better assimilated.

The majority of us lack vitamin D (insufficient exposure to sunlight, age, skin pigmentation, etc.). In the long term, deficiency increases the risk of fracture and osteoporosis.

Taking 1000 to 2000 IU of vitamin D3 daily helps to meet the body's needs and benefit from its many benefits.

Placed in the spotlight during the Covid-19 crisis, vitamin D plays an essential role in many functions of the body.

However, although the body has the capacity to synthesize it naturally under the action of the sun's rays, many of us are deficient in it, which can have harmful consequences for our health.

What is it for ? Where is it found? How to get enough intake and why supplement? Discover our answers.

vitamin d cholecalciferol benefits role

What is vitamin D?

Vitamin D is a fat-soluble vitamin (i.e. soluble in fats) which is involved in many functions in the body. Beneficial for immunity, muscle function, bone and tooth health, it is necessary for everyone (children, adults, seniors, athletes, etc.).

Here are the recommended daily nutritional intakes expressed in International Units (IU):

  • From 0 to 1 year: 400 IU;
  • From 1 year to 70 years: 600 IU;
  • Over 70 years: 800 IU

These are the minimum intakes to avoid developing a deficiency.

The main sources of vitamin D

Vitamin D exists in two forms: vitamin D2 (or ergocalciferol) and vitamin D3 (or cholecalciferol).

Among these two forms, D3 is preferred because it is considered the natural form of vitamin D, more bioavailable than D2.

Vitamin D can be obtained in two ways:

  • through food : it is found in fatty fish (herring, mackerel, sardines, salmon, tuna), certain oils (cod liver oil), products enriched with vitamin D (yogurts for example), the yolk of egg, dark chocolate...;
  • by exposure to the sun : the body synthesizes it naturally when the skin is exposed to the sun's ultraviolet rays (which also explains its nickname " sun vitamin "!).

Why are many of us deficient in vitamin D?

Although exposing your skin to the sun for 10 to 15 minutes each day a week is enough to get enough vitamin D, recent studies have shown that a large portion of the population suffers from a vitamin D deficiency. It is also estimated that 80% of French people are deficient in vitamin D.

Vitamin D deficiency can result from several factors: insufficient dietary intake of vitamin D, lack of exposure to the sun's rays (especially in geographical areas with little sunlight or pollution), use of sunscreen, heavily pigmented, age (as we age, the skin produces less vitamin D).

Lack of vitamin D can manifest itself in different ways. In adults, the most common symptoms of vitamin D deficiency are fatigue, bone and muscle pain (example: difficulty climbing stairs or getting up from a low chair), immune weakness, low morale, dizziness...

In the long term, the deficiency can lead to an increased risk of fractures (especially of the hip) and muscle and ligament damage. It can also lead to osteoporosis.

We recommend you

Vitamin D3

Highly bioavailable micro-encapsulated vitamin D3V®.

  • ✅ Natural and bioavailable form
  • ✅ Plant origin (algae)
  • ✅ 2000 IU for 2 capsules
  • ✅ 2 months of treatment
See the product sheet

What are the benefits of vitamin D?

Vitamin D has a wide range of benefits. Here are the main ones:

It supports the immune system

Vitamin D contributes to the proper functioning of the immune system on several levels. Thus, by influencing the proteins of intestinal cells, it plays a role in the good health of the intestinal flora, which limits the development of diseases. Vitamin D also has anti-inflammatory properties because it increases the level of Th2 lymphocytes, which help fight pathogens.

It contributes to good bone health

This is the major benefit of vitamin D: it is known to improve the absorption of calcium and phosphorus, mineral salts essential to the strength of bones and teeth. You've often heard it said: "to have strong bones, you have to eat calcium!" » - that's absolutely right. Vitamin D contributes to good bone and dental health because it regulates the level of calcium in the blood, but also because it facilitates intestinal absorption of calcium.

In other words, calcium is better used by the body when it is associated with a sufficient dose of vitamin D (mainly D2 and D3). Calcium and phosphorus are, likewise, very important for good oral health, particularly to combat cavities, periodontitis and other oral conditions.

It helps increase muscle strength

Studies have shown the role of vitamin D in mitochondrial function. Mitochondria are small organelles that help generate ATP (Adenosine TriPhosphate), the “fuel” of cells. This function is particularly influenced by vitamin D. A vitamin D deficiency reduces the efficiency of mitochondrial function, which leads to reduced fitness, muscle fatigue, and muscle loss/instability. For example, a study showed that vitamin D supplementation increased muscle strength in dancers or elderly people with reduced mobility.

It reduces the risk of fractures due to osteoporosis

Osteoporosis is a skeletal disease, the prevalence of which increases with age. It results in a drop in bone density, which makes the bones more fragile, and therefore greatly increases the risk of fractures. To prevent this disease or reduce its effects, it is advisable to increase your consumption of calcium and vitamin D, especially for seniors. As mentioned above, the cumulative action of calcium and vitamin D helps strengthen bone density , and therefore counteract the effects of osteoporosis.

It helps prevent various diseases

Finally, vitamin D helps protect against several diseases. Among them are cancers (breast, pancreas, and prostate, in particular), diabetes (both types), and certain cardiovascular or infectious diseases.

In winter, thanks to its role in the immune system, vitamin D limits the risk of colds or flu. It also reduces the risk of mental illnesses such as Alzheimer's, but also the risk of hypertension.

How to choose the right vitamin D food supplement?

If you are deficient in vitamin D, we of course first invite you to expose yourself more frequently to the sun's rays and to increase your consumption of foods rich in vitamin D.

To supplement your intake and have sufficient levels of vitamin D, it may be appropriate to supplement. But not just anyhow!

Although almost all food supplements are in the form of vitamin D3 (which, as we recall, is the natural form of vitamin D), not all of them are equal. Several selection criteria must therefore be taken into account:

Where vitamin D comes from

The vitamin D3 found in supplements generally comes from lanolin , a fatty substance extracted from sheep's wool. Although of natural origin, this form is not compatible with a vegan diet.

This is why we preferred to opt for a plant form of vitamin D , extracted from algae , which is suitable for everyone.

Vitamin D dosage

For balanced intakes to meet the body's needs and benefit from the benefits of vitamin D for the body, we advise you to opt for a supplement providing 1,000 to 2,000 IU per day , i.e. 25 to 50 µg (2,000 IU being the maximum recommended level in France).

The galenics

Vitamin D exists in different forms: ampoules, drops, tablets, capsules, capsules... It's up to you to see what you prefer. As with a large part of our range, we favor the capsule format which combines ease of use, precise dosage measurement and absence of taste.

Vitamin D: contraindications

Vitamin D is not recommended if you suffer from hypercalcemia (blood calcium level that is too high).

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