Can Vitamin C Affect Your Blood Glucose?

Vitamin C, or ascorbic acid, is an antioxidant synthesized by plants and is an essential nutrient in the human diet. Vitamins are organic compounds that regulate myriad body functions, including but not limited to oxygen delivery and consumption, tissue and cell growth, nerve transduction, hormone regulation, and metabolism. A well-rounded diet rich in vitamin C may help to control your blood glucose levels, but discuss this with your doctor.

Function

Vitamin C is used in the body for protein synthesis, wound healing, immune function, iron absorption and fighting cellular damage caused by free radicals as an antioxidant. Vitamin C deficiency can cause scurvy, which is characterized by fatigue, weakness, frailty and anemia. The body cannot produce sufficient vitamin C on its own, nor does it store vitamin C. Therefore, it is essential to obtain vitamin C through diet or supplementation.

The Facts

A study published by Sargeant et al. in "Diabetes Care" in 2000 found that mean plasma vitamin C levels were lower in those with high blood glucose, suggesting that increasing plasma vitamin C levels may prevent or reduce the risk of type 2 diabetes. A subsequent study published in the November 2007 issue of "Indian Journal of Medical Research" corroborated that increasing plasma levels of vitamin C through dietary supplementation of 1,000 mg per day decreased blood glucose levels. However, excessive vitamin C intake of at least 300 mg per day through supplementation, not diet, has been associated with cardiovascular disease and other serious health effects, according to the National Institutes of Health Office of Dietary Supplements.

Recommended Intake and Dietary Sources

Meeting the recommended intake for vitamin C can be achieved with a healthy diet. The recommended dietary allowances for vitamin C are age-specific; but in general, adult males 19 years and older need approximately 90 mg per day, and adult females 19 years and older need approximately 75 mg per day, according to the Office of Dietary Supplements at the National Institutes of Health. Vitamin C needs are lower in children and adolescents, and higher during pregnancy and lactation. Vitamin C intake should not exceed 2,000 mg per day. Fruits and vegetables are the best sources of vitamin C. Rich sources include citrus fruits and juices, strawberries, kiwifruit, pineapple, guava, melon, tomatoes and tomato juice, potatoes, peppers, broccoli, Brussels sprouts, cabbage, cauliflower and green leafy vegetables.

Considerations

Your own health and medical history determines how much vitamin C is right for you. Many individuals can meet their nutrient needs for vitamin C through diet alone. Because vitamin C is water-soluble, it is easily destroyed by prolonged storage or heat. Eating fresh, raw, vitamin C rich foods is best. Steaming or microwaving instead of boiling may lessen cooking losses. Always consult with a physician before taking a new dietary supplement or starting a new diet plan.