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"Can you get an overload of vitamin C?"

ZocdocAnswersCan you get an overload of vitamin C?


My brother take a vitamin c tablet every hour when he has a cold. Is this wise or could he overload his system?


Thank you for your question about Vitamin C supplementation and I recommend discussing your concern further with your doctor. Vitamin C is an important nutrient in our diet which is important for the proper synthesis of collagen in our connective tissues. This is evident in people who go three or more months without fruits or vegetables who can develop scurvy, a condition characterized by gum bleeding, bruising, pinpoint bleeding under the skin, muscle and joint pain. However, Vitamin C has not been shown to have a huge effect in preventing the common cold. Vitamin C has only been shown to have some effect in decreasing the common cold in high intensity athletes exposed to extreme environmental conditions such as marathon runners and skiers. Therefore, it is unlikely that your brother is benefiting greatly from Vitamin C supplementation, especially since he is taking Vitamin C after already developing the cold. Large quantities of Vitamin C have been linked to diarrhea and abdominal bloating. Very large doses over a few milligrams may have an association with kidney stones containing calcium, however this applies more to patients on dialysis or those already predisposed to these types of kidney stones. The recommended daily dose of Vitamin C to prevent scurvy is 90 mg/day in males. A diet rich in fruits and vegetables such as citrus fruits, broccoli, cauliflower, strawberries and spinach is an excellent natural source for Vitamin C. If you have any further questions about Vitamin C and its risks and benefits, please speak with your doctor.

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