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Here’s the vitamin C conundrum: We can’t live without this essential nutrient, yet our bodies don’t make or store it. To replenish our supplies, we turn to antioxidant-rich fruits and vegetables—citrus, kiwis, strawberries, tomatoes, red and green peppers, broccoli—yet dietary vitamin C degrades easily during storage and cooking. Perhaps that’s why 25 percent of Americans get less than the recommended intake.
Vitamin C helps make collagen to repair skin and blood vessels, maintains bones and teeth, and protects against free-radical damage that can lead to premature aging, heart disease, and cancer. (Noticeable symptoms of a deficiency—gingivitis, scaly skin, nosebleeds—only occur in severe cases, but low levels of vitamin C have been linked to conditions including hypertension and atherosclerosis.) Recent studies suggest that vitamin C may mimic certain heart benefits from exercise and reduce bloodstream levels of LDL (“bad”) cholesterol and triglycerides. And regular supplementation can reduce the duration and severity of the common cold. Finally, vitamin C is also a particular ally of vegetarians, enhancing iron absorption from plant-based sources.
Related: Blueberry-Beet Smoothie Recipe
Use It Right
According to the National Academy of Sciences, women require 75 mg of vitamin C daily, while men need 90 mg. More may be better: Studies have found that taking 250–500 mg twice a day (preferably with food) is beneficial. Supplements usually contain vitamin C in the form of ascorbic acid. For people with sensitive stomachs, a less acidic option is a buffered or esterified formula.
Excess vitamin C is eliminated by the body, though taking 2 g or more per day can cause gastrointestinal upset. Vitamin C may interact with certain medications or conditions, resulting in lower levels of the vitamin and/or higher levels of estrogen or metal absorption. Consult your doctor before supplementing if you have iron buildup, kidney problems, or are being treated for cancer, or if you’re taking aspirin, acetaminophen, NSAIDs, aluminum-based antacids, oral contraceptives, or hormone-replacement therapy.