Side effects of multivitamin supplements
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Common Side Effects of Multivitamin Supplements
Multivitamin supplements are widely used around the world, often with the belief that they are completely safe. However, research shows that side effects can occur, especially with high doses or long-term use.
Gastrointestinal Side Effects: Constipation, Diarrhea, and Stomach Issues
The most commonly reported side effects of multivitamin supplements are mild gastrointestinal symptoms. These include constipation, diarrhea, and general stomach discomfort. These effects are usually minor and not dangerous, but they can be bothersome for some users 2347.
Adverse Effects from High Doses of Specific Vitamins
Taking high doses of certain vitamins, especially fat-soluble ones like vitamins A, D, and E, as well as water-soluble vitamins like folic acid, can be harmful. High doses may lead to toxicity or other negative health effects, so it is not always safe to assume that more is better 16. For example, excessive vitamin A can cause liver problems, and too much vitamin D can lead to high calcium levels in the blood.
Prevalence and Awareness of Side Effects
Studies show that a minority of people using multivitamin supplements experience side effects. In surveys, about 15% of users reported harmful effects, with most people believing that multivitamins are important for health and often using them without a prescription 23. Many users are not fully aware of the potential side effects, and some believe that multivitamins have no risks at all.
Long-Term Safety and Use Within Recommended Limits
When multivitamin supplements are used within the recommended daily limits, studies have found that they are generally safe for long-term use. There is no evidence that taking standard doses increases the risk of serious health problems or mortality. However, exceeding the recommended amounts can increase the risk of side effects .
Special Populations: Athletes and Post-Surgery Patients
In athletes, multivitamin and mineral supplements did not cause any serious toxic side effects, but they also did not provide measurable benefits if the diet was already balanced . For people who have had bariatric surgery, gastrointestinal side effects are a common reason for not taking multivitamin supplements regularly .
Conclusion
Most people tolerate multivitamin supplements well, especially when taken at recommended doses. The most common side effects are mild digestive issues. However, high doses of certain vitamins can be harmful, and a small percentage of users do experience negative effects. It is important to use multivitamin supplements as directed and to be aware that "more" is not always "better" when it comes to vitamins 123467.
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