Vitamins are one of the seven essential nutrients for the human body and a type of organic substance necessary to maintain life activities. Common vitamins include Vitamin A, Vitamin B1, Vitamin B2, Niacin, Vitamin B6, Biotin, Folic Acid, Vitamin B12, Choline, Vitamin C, Vitamin D, Vitamin E, and Vitamin K. While vitamins are beneficial, taking them also requires careful consideration.
In general, healthy people will not be deficient in vitamins and other nutrients through a balanced diet. The main causes of vitamin deficiency are threefold: insufficient intake, such as from picky eating or reduced food intake due to illness; impaired absorption and utilization, such as from indigestion; and increased demand, such as prolonged computer use which can lead to increased consumption of Vitamin A. Vitamin deficiency is a gradual process; deficiency symptoms only appear when a certain vitamin is chronically under-consumed or excessively depleted. At this point, vitamin supplementation should be used rationally under the guidance of a physician or pharmacist. Improper use may cause various adverse reactions.
Oral intake of Vitamin C over 4 grams can easily lead to stone formation
Vitamin C is the most familiar vitamin to everyone, but taking more than 4 grams orally per day can cause urates to precipitate in the urinary tract and form stones. Taking more than 1 gram of Vitamin C orally per day can cause skin redness, increased intestinal motility leading to abdominal cramps and diarrhea. If children take high doses of Vitamin C for a long time, it may affect bone development.
Excess Vitamin A can cause poisoning
Vitamin A plays an important role in bone growth and the maintenance of gonadal function, but excessive intake can also lead to poisoning. Acute poisoning manifests as dizziness, drowsiness, headache, vomiting, and diarrhea; chronic poisoning manifests as bone and joint pain, swelling, skin itching, fatigue, limb weakness, irritability, abdominal pain, and oligomenorrhea in women.
Excess Vitamin E can cause blurred vision
Vitamin E is an antioxidant that is believed to have effects such as preventing cardiovascular and cerebrovascular diseases and anti-aging, and is widely used. However, if taken for a long time at a daily dose of 400-800 milligrams, it can cause blurred vision, breast enlargement, flu-like syndrome, headache, dizziness, nausea, and stomach cramps; long-term use at a daily dose exceeding 800 milligrams will alter endocrine metabolism and immune response, reduce sexual function, and may lead to thrombophlebitis or embolism.
Excess Vitamin D can cause poisoning
Vitamin D is indispensable for the body's calcium metabolism and is very effective in preventing and treating rickets in children. However, excessive or large doses taken in a short period can also lead to severe poisoning reactions. The toxic dose varies significantly among individuals; for example, some children experience stunted growth after long-term intake of 1800 units of Vitamin D.
Excess Vitamin B6 can cause drug dependence
Vitamin B is a very important water-soluble vitamin. It has been reported that taking 200 milligrams of Vitamin B6 daily can lead to drug dependence.
It should be noted that the above-mentioned vitamin poisonings usually only occur under the condition of long-term excessive intake. If additional vitamin supplementation is required for medical reasons, it should be used safely under a doctor's guidance. It should be reminded that vitamin supplements cannot replace vegetables. "Supplementation by medicine is not as good as supplementation by food," and obtaining vitamins through food is the safest way.