How much vitamin C you need per day depends on your age, sex, pregnancy and lactation status, and if you smoke. Here are the guidelines and general limits.

Grapefruits are good sources of vitamin C, but foods like red acerola cherries, red bell peppers, and guavas have even more of the nutrient.

Share on Pinterest Can vitamin D boost longevity? Here’s what the latest research says. Image credit: Catherine Falls Commercial/Getty Images Recent research has investigated the potential health ...