Food supplements: beware!
Food supplements have their place in certain cases, but less so than you might think and... be careful!
In my opinion, most of us only need vitamin D supplementation. Then there are specific supplementation needs for pregnant and breastfeeding women, women on hormonal contraception and infants. There are also supplementation requirements for:
People who work at night: vitamin A supplementation is advisable but should be stopped before considering pregnancy (no vitamin A supplementation during pregnancy!).
Heavy alcohol consumers: supplementation with a B vitamins and magnesium is recommended. It's also a good idea to have a blood test to check for any other deficiencies (selenium, zinc, etc.) and for excess iron (alcohol increases its absorption).
Smokers: supplementation with vitamin C and B vitamins (including B2, B6 and B9) is recommended. Caution: never supplement smokers with vitamin A in the form of beta-carotene (possible increased risk of lung cancer).
I would define the following principles of supplementation:
Before taking supplements, you should first correct your diet. Then carry out biological tests to identify any deficiencies. As these tests are not necessarily a good reflection of what's going on in your body, you should also take into account any symptoms you may be experiencing.
If there are deficiencies and/or symptoms, also check whether you have a problem with dysbiosis or intestinal hyperpermeability (biological analyses).
If you are supplementing, it is important to:
Split your intake as much as possible. For example, if you're taking 200 mg of vitamin C, it's best to take it in two 100 mg doses at different times of the day.
Choose natural sources. This goes for vitamin A beta-carotene, vitamin B9 and vitamin E. For other nutrients, if the form is synthetic, it must at least be bio-identical to the natural form.
Avoid excipients (what is added to nutrients to form tablets or capsules) as much as possible. Some excipients can even inhibit intestinal absorption of nutrients. Supplements in powder or liquid form are preferable to solid forms, which contain more excipients. In the case of powders, beware of capsules containing gelatin, which may be of animal origin and come from intensive livestock farming, with the attendant risks.
Avoid colorants and other additives.
Choose supplements guaranteed to be GMO- and nanoparticle-free.
Avoid long-acting forms, as they contain additives to slow release in the intestine.
Avoid taking complexes containing both iron and copper, or calcium and magnesium.
Iron and copper: in the presence of iron or copper, hydrogen peroxide can give rise to the hydroxyl radical, the most dangerous of oxidants (Fenton's reaction).
Calcium and magnesium: they compete for passage through the intestinal mucosa, since they both use ion channels. If you need to take both calcium and magnesium, you should separate the two.
Finally, there are many other points to consider, depending on the vitamin, mineral salt, amino acid, fatty acid, or other type of nutrient involved. Impossible to cover them all here, I'll just mention the most important:
For vitamin C, max 200 mg per dose, as intestinal absorption is limited beyond that.
For vitamin D, take D3 (cholecalciferol), not D2 (ergocalciferol).
I advise against calcium supplementation, to avoid calcification, particularly of the arteries. In the event of supplementation, an adequate magnesium intake is essential, as it regulates calcium and promotes its use in the bones rather than its deposition in the arteries. I recommend 1 mg of magnesium for every 2 mg of calcium. However, calcium and magnesium should be taken at separate times. Take calcium in the form of calcium pidolate before or at the beginning of a meal.
For amino acids, take them in the "L" form, identical to those in our body, and not in the mirror "D" form.
For omega 3, keep them refrigerated and avoid consuming them already oxidized. To do this, look at the totox index, which should be a maximum of 15. Most omega-3 supplements exceed this standard, even when they contain vitamin E. If the index is not known, you can crunch a capsule and taste the oil to check that it doesn't have an unpleasant or rancid taste.
Don't supplement with calcium without also supplementing with vitamin D, to limit the risk of this calcium being deposited in your arteries. Calcium needs vitamin D to be absorbed.
Don't supplement with vitamin D without also supplementing with magnesium, if you're magnesium deficient. Vitamin D needs magnesium for the enzymes that convert its inactive form (cholecalciferol) into active forms (calcitriol and calciferol), and for the enzyme that converts the active forms back into the inactive form in case of excess.
To find out more, also read these articles:
On methylation: https://isabellemaesnutrition.com/en/methylation
Food supplements picture by Diana Polekhina