From the Guidelines
The daily recommended dose of vitamin C for adults is at least 200 mg per day, considering the latest evidence on optimal health and the increased requirements for smokers and individuals with certain health conditions. Vitamin C is essential for collagen production, wound healing, immune function, and acts as an antioxidant protecting cells from damage. Most people can obtain sufficient vitamin C through a balanced diet rich in fruits and vegetables, particularly citrus fruits, strawberries, kiwi, bell peppers, broccoli, and tomatoes. The upper limit for vitamin C intake is 2,000 mg per day; exceeding this amount may cause digestive issues like diarrhea and stomach cramps 1. For those considering supplements, it's best to take them with meals to improve absorption and reduce potential stomach irritation. Smokers, in particular, may need higher intakes of vitamin C, with some studies suggesting an additional 130-200 mg per day to compensate for the increased turnover of vitamin C due to smoking 1.
Some key points to consider:
- The recommended daily intake of vitamin C varies globally, with some countries recommending as little as 40 mg per day, while others recommend up to 220 mg per day 1.
- The Food and Nutrition Board of the United States National Academy of Sciences has established RDAs for vitamin C, which have been revised over the years, with the current RDA being 75-90 mg per day for adults 1.
- However, the latest evidence suggests that these recommendations may be too low, and that higher intakes of vitamin C may be necessary for optimal health, particularly for smokers and individuals with certain health conditions 1.
- Vitamin C is an essential nutrient that can be obtained through a balanced diet, and supplements should only be considered if necessary, and under the guidance of a healthcare professional.
Overall, while the exact recommended daily intake of vitamin C may vary depending on individual circumstances, the latest evidence suggests that higher intakes, of at least 200 mg per day, may be necessary for optimal health, particularly for smokers and individuals with certain health conditions 1.
From the Research
Daily Recommended Dose of Vitamin C
- The daily recommended dose of vitamin C is not explicitly stated in the provided studies, but they suggest that the current recommended dietary allowances may be insufficient 2.
- Research has shown that vitamin C has important metabolic actions in several biological processes, and its deficiency can be associated with various diseases, such as cardiovascular disease and pneumonia 3, 4.
- Studies have found that patients with certain conditions, such as type 2 diabetes and community-acquired pneumonia, often have depleted vitamin C status and elevated oxidative stress, suggesting a potential benefit from increased vitamin C intake 3, 4.
- Animal studies have also investigated the effects of vitamin C deficiency and supplementation, with findings suggesting that hepatic vitamin C levels in deficient mice may not reach optimal levels even with high-dose supplementation 5.
- The metabolic cooperation between ascorbic acid and glutathione, two naturally occurring antioxidants, has also been studied, with results indicating a compensatory network that can help decrease oxidative stress 6.