Side effects of multivitamins
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Side Effects of Multivitamins
Common Side Effects of Multivitamins
Multivitamins are widely used to address vitamin deficiencies and promote overall health. However, they are not without side effects. Commonly reported side effects include gastrointestinal issues such as constipation and diarrhea 310. These side effects are generally mild and do not pose significant health risks.
Specific Adverse Effects of Certain Vitamins
Certain vitamins, particularly when taken in high doses, can cause adverse effects. For instance, fat-soluble vitamins like vitamin A, D, and E, as well as water-soluble vitamins like folic acid, can lead to negative health outcomes if consumed excessively. High doses of these vitamins have been associated with various adverse events, including toxicity and detrimental health effects .
Multivitamins and Combined Oral Contraceptives
A study examining the use of multivitamins alongside combined oral contraceptives (COCs) found that multivitamins could reduce some of the side effects associated with COCs, such as nausea, mood changes, weight gain, and breast tenderness. This suggests that multivitamins might mitigate certain side effects when used in specific contexts .
Multivitamins in Special Populations
Children with Down Syndrome
In children with Down syndrome, high-dosage multivitamin and mineral supplements were associated with decreased developmental progress and various side effects. Despite these adverse effects, some parents reported improvements in general appearance and skin freshness, indicating a complex risk-benefit scenario .
Pregnant Women
In high-income countries, multivitamin use during pregnancy has been linked to a reduced risk of certain adverse birth outcomes, such as neural tube defects and cardiovascular defects. However, the overall quality of evidence is low, and routine use should be approached with caution .
Long-Term Safety of Multivitamins
Long-term use of multivitamins, particularly those containing a combination of at least nine vitamins and three minerals at recommended dietary allowance levels, appears to be safe. Studies have shown that such supplementation does not result in significant adverse effects or increased mortality, even over extended periods exceeding ten years 89.
Awareness and Usage Patterns
A study conducted in Saudi Arabia revealed that a significant portion of the population uses multivitamins without medical prescription, and many are unaware of potential side effects. Despite this, the majority of users consider multivitamins important for their health, highlighting a gap in public awareness and education regarding the safe use of these supplements 310.
Conclusion
While multivitamins can offer health benefits, they are not free from side effects. Common issues include gastrointestinal discomfort, and specific vitamins can cause adverse effects if taken in high doses. Special populations, such as children with Down syndrome and pregnant women, may experience unique risks and benefits. Long-term use of multivitamins at recommended levels appears to be safe, but public awareness about their proper use and potential side effects needs improvement.
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