Picking the “more useful” food, many people wonder: if I’ll eat 500% of the value of vitamin C, 1000% of vitamin B12, is that worth doing?
Excess vitamins, trapped in our body along with the regular daily food are absolutely safe. But if you are taking supplemental vitamins or eat specially fortified foods, you should bear in mind some rules and restrictions. In existing norms of consumption there are no special restrictions, other than for vitamin A. Below we present the recommendations of the American Academy of Sciences:
| Nutrient | The maximum allowable | The ratio of the consumption rate |
|---|---|---|
| Vitamin a (retinol), mcg | 3000* | 330%* |
| Vitamin C (ascorbic-TA), mg | 2000 | 2200% |
| Vitamin D (cholecalciferol) µg | 50 | 500% |
| Vitamin E (α-tocopherol) mg | 1000* | 6700%* |
| Vitamin K | – | no data |
| Vitamin B1 (thiamine) | – | no data |
| Vitamin B2 (Riboflavin) | – | no data |
| Vitamin PP (B3, Niacin), mg | 35* | 175%* |
| Vitamin B5 (Pantothenic-TA) | – | no data |
| Vitamin B6 (pyridoxine), mg | 100 | 5000% |
| Vitamin B9 (folic to-that), mcg | 1000* | 250%* |
| Vitamin B12 (cyanocobalamin), mcg | – | no data |
| Choline, mg | 3500 | 700% |
| Biotin | – | no data |
| Carotenoids | – | no data |
| Boron, mg | 20 | 2000% |
| Calcium, mg | 2500 | 250% |
| Chrome | – | no data |
| Copper, mcg | 10000 | 1000% |
| Fluoride, mg | 10 | 250% |
| Iodine, mcg | 1100 | 730% |
| Iron, mg | 45 | 450% |
| Magnesium, mg | 350* | 87%* |
| Manganese, mg | 10 | 500% |
| Molybdenum, mcg | 2000 | 2900% |
| Phosphorus, mg | 4000 | 500% |
| Potassium | – | no data |
| Selenium, mcg | 400 | 570% |
* this limitation is only imposed on the nutrients taken in the form of additional drugs and/or in artificially enriched foods, and not for nutrient consumption of common products.
Vitamin A.
Large amounts of vitamin A in the form of retinol is stored in the liver, accumulates there the excessive daily dose as well. Therefore, regular consumption of liver in large amounts can lead to chronic poisoning with retinol, although the dose needed for this is very large. Considered dangerous daily intake of more than 7,500 mcg (800% of normal) for more than 6 years, or more than 30,000 mcg for more than 6 months. Acute poisoning with vitamin A is possible with single doses of more than 7500 mg/kg (ie about 50 000% of normal), such doses may be contained in the liver of polar animals — polar bears, walrus, etc … Similar to the toxicity described by the first explorers from the end of the XVI century.
Especially dangerous is the excess of retinol for pregnant women, because of its teratogenic action. Therefore, there is medical advice to women who were being treated with vitamin A for several months before pregnancy to the exhaustion of excess reserves of retinol in the liver. And this vitamin is necessary to follow during pregnancy, particularly in the use of “useful supplements”.
In the local standards of maximum allowable consumption level of retinol determined in 3000 micrograms for all adults, with no division into natural and artificial sources.
However, most people in the mid-latitudes get enough vitamin A in the form of beta-carotene. And it is very healthy, because it, unlike retinol, is perfectly safe in any reasonable quantity. Even if you eat beta-carotene in absolutely unreasonable doses, you are in no danger except that your nose or your palms will turn orange (photos from Wikipedia):
This condition is absolutely safe (except for the fear of the people in your surroundings:) and will pass if you stop to absorb the carrots in megadose.
Thus, if you are not using additional drugs and do not abuse the liver, a fear of excess of any nutrient is not necessary. Our body is designed for a large range of consumption of vitamins and minerals.
Can You Overdose on Vitamins?
Mire about the vitamins and minerals read in specialized sections of the website.