You all thought you knew all about vitamin D and its benefits, but you might be surprised.
There are 5 different types of vitamin D, but let's take a closer look at vitamin D3.
The one our bodies make thanks to the sun!
Here's what you really need to know.
Vitamin D3: presentation
There is not one vitamin D, but several, all numbered from 1 to 5.
Vitamin D3 refers to cholecalciferol, a vitamin D synthesised by the skin under the influence of the sun's ultraviolet rays.
Vitamin D3 is different from vitamin D2 (ergocalciferol), which we get from food.
However, they play the same roles in the body.
If our bodies are able to produce vitamin D3 when we expose our skin to the sun's rays, there are also food sources.
Few foods are able to provide us with an interesting amount.
However, health authorities have set a recommended daily intake of 600 IU (International Units), or 15 µp.
After the age of seventy, our needs increase and reach 800 IU or 20 µp.
We can meet these needs through diet, supplementation and exposure to sunlight.
The best sources of vitamin D3
Some foods are particularly rich in cholecalciferol.
This is the case with cod liver oil and halibut oil.
It is found in sardines, anchovies, salmon, tuna, poultry offal and mushrooms.
This form of vitamin D3 is also found in eggs and butter.
Lichen is a plant source. It is not a plant, but an association between a fungus and an algae, which explains the presence of vitamin D3 in its composition.
The biological roles and benefits of vitamin D3
What are the health effects of cholecalciferol?
Vitamin to prevent osteoporosis
This vitamin is involved in the process of binding calcium to the bones.
Logically, a vitamin deficiency can affect this process and increase the risk of osteoporosis.
In fact, osteoporosis is a common sign of a lack of vitamin D in the body.
Studies have shown that supplementation with this vitamin increases bone density in premenopausal and menopausal women.
The older you get, the more important the dosage is for this to be effective.
Supplementation may also reduce the risk of fractures and falls in older people.
As mentioned above, vitamin D2 and vitamin D3 perform the same functions in the body, but both are essential for us.
Studies of their effects show that cholecalciferol helps to strengthen the immune system.
It is particularly effective in fending off external aggressions, but also in recovering from illnesses such as flu, infections, pneumonia, etc.
This vitamin helps to reduce the risk of disease and speeds up the recovery of those who are ill and the risk of relapse.
Improving cognitive function
Cholecalciferol is an essential vitamin for the proper functioning of the cognitive system.
It is directly involved in neuroprotection, although more research is needed to confirm this.
Scientists are certain that the vitamin is indirectly involved in protecting neurons and controlling cognitive disorders caused by inflammation.
On the other hand, vitamin D deficiency is a cause of impairment in the elderly.
The vitamin is therefore used to prevent neurodegenerative diseases such as Alzheimer's.
Vitamin D3 works in the same way as vitamins E and C in preventing type 2 diabetes.
This is due to its ability to modulate oxidative stress and inflammation.
Chronic inflammation, immune imbalance and oxidative stress are factors that promote obesity, insulin resistance and metabolic syndrome.
These are three "critical" stages that favour the development of disease.
Cholecalciferol helps regulate the body's response to insulin, but it also has anti-inflammatory properties.
As such, it is effective in preventing type 2 diabetes.
A deficiency, on the other hand, can increase the risk.
Preventing cardiovascular risk
Cholecalciferol appears to help reduce the risk of cardiovascular disease and accidents, as well as the risk of mortality associated with the latter.
Studies show that vitamin D3 supplementation can help reduce all these risks by protecting the arteries against a factor that promotes high blood pressure: the hardening of the arterial walls.
Information and use of this vitamin
Vitamin D3 supplementation should be considered under medical advice.
This means that people living in latitudes where there is a lack of winter sunshine are the main victims of vitamin D3 deficiency.
Consequences of vitamin D3 deficiency
What makes vitamin D3 so special is the risk of deficiency.
Few foods contain it, and not all of us live in latitudes where we get enough sun all year round.
Winter is a season that is prone to vitamin D3 shortages and deficiencies.
Vitamin deficiency is most often linked to this lack of exposure to UVA rays.
And it can cause several health problems.
The signs of vitamin D3 deficiency are many and should alert you.
They include muscle weakness and pain, high blood pressure, hypocalcaemia and cognitive decline.
We can also mention osteoporosis, depression, rheumatism in children...
In pregnant women, vitamin deficiency can also increase the risk of pre-eclampsia.
The risk of overdosing on vitamin D3
If a deficiency is a problem to be avoided, one should not fall into the opposite excess and suffer a vitamin overdose.
So if you have any symptoms or are in any doubt, see your doctor, who will prescribe a blood test.
An excess of vitamin D can be just as serious as a deficiency.
Hypervitaminosis D can increase calcium levels in bone tissue and the blood, leading to hypercalcaemia.
And excess calcium can have serious consequences: joint pain, kidney stones, nausea, pancreatitis, etc.
Dosage
Do you need to supplement your diet with food supplements?
In this case, the dosage depends on the health problem.
To treat osteoporosis, between 1,000 and 2,000 IU of D3 are combined with 1,200 mg of calcium.
For the prevention of the disease, the dosage evolves.
It's 800 to 2,000 IU of D3 and 1,200 mg of calcium.
Finally, for adults under 50 who want to boost their immunity in winter, the usual dosage is 400 to 1,000 IU of D3 a day.