What is it?
Vitamin C is an essential vitamin, meaning your body can’t produce it. Yet, it has many roles and has been linked to impressive health benefits. It’s water-soluble and found in many fruits and vegetables, including oranges, strawberries, kiwi fruit, bell peppers, broccoli, kale, and spinach. The recommended daily intake for vitamin C is 75 mg for women and 90 mg for men. While it’s commonly advised to get your vitamin C intake from foods, many people turn to supplements to meet their needs.
- May reduce your risk of chronic disease Vitamin C is a powerful antioxidant that can strengthen your body’s natural defenses. Antioxidants are molecules that boost the immune system. They do so by protecting cells from harmful molecules called free radicals. When free radicals accumulate, they can promote a state known as oxidative stress, which has been linked to many chronic diseases. Studies show that consuming more vitamin C can increase your blood antioxidant levels by up to 30%. This helps the body’s natural defenses fight inflammation.
- May help manage high blood pressure Approximately one-third of American adults have high blood pressure. High blood pressure puts you at risk of heart disease, the leading cause of death globally. Studies have shown that vitamin C may help lower blood pressure in both those with and without high blood pressure. An animal study found that taking a vitamin C supplement helped relax the blood vessels that carry blood from the heart, which helped reduce blood pressure levels. Moreover, an analysis of 29 human studies found that taking a vitamin C supplement reduced systolic blood pressure (the upper value) by 3.8 mmHg and diastolic blood pressure (the lower value) by 1.5 mmHg, on average, in healthy adults. In adults with high blood pressure, vitamin C supplements reduced systolic blood pressure by 4.9 mmHg and diastolic blood pressure by 1.7 mmHg, on average. While these results are promising, it’s not clear whether the effects on blood pressure are long term. Moreover, people with high blood pressure should not rely on vitamin C alone for treatment.
- May lower your risk of heart disease Heart disease is the leading cause of death worldwide. Many factors increase the risk of heart disease, including high blood pressure, high triglyceride or LDL (bad) cholesterol levels, and low levels of HDL (good) cholesterol. Vitamin C may help reduce these risk factors, which may reduce heart disease risk. For example, an analysis of 9 studies with a combined 293,172 participants found that after 10 years, people who took at least 700 mg of vitamin C daily had a 25% lower risk of heart disease than those who did not take a vitamin C supplement. Interestingly, another analysis of 15 studies found that consuming vitamin C from foods — not supplements — was linked to a lower risk of heart disease. However, scientists were unsure whether people who consumed vitamin-C-rich foods also followed a healthier lifestyle than people who took a supplement. Thus, it remains unclear whether the differences were due to vitamin C or other aspects of their diet. Another analysis of 13 studies looked at the effects of taking at least 500 mg of vitamin C daily on risk factors for heart disease, such as blood cholesterol and triglyceride levels. The analysis found that taking a vitamin C supplement significantly reduced LDL (bad) cholesterol by approximately 7.9 mg/dL and blood triglycerides by 20.1 mg/dL. In short, it seems that taking or consuming at least 500 mg of vitamin C daily may reduce the risk of heart disease. However, if you already consume a vitamin-C-rich diet, then supplements may not provide additional heart health benefits.
Unproven claims about vitamin C
Prevents the common cold. While vitamin C appears to reduce the severity of colds and recovery time by 8% in adults and 14% in children, it does not prevent them. Reduces cancer risk. A handful of studies have linked vitamin C intake to a lower risk of several cancers. However, most studies have found that vitamin C does not affect the risk of developing cancer. Protects against eye disease. Vitamin C has been linked to reduced risks of eye diseases like cataracts and age-related macular degeneration. However, vitamin C supplements have no effect or may even cause harm. May treat lead toxicity. Although people with lead toxicity appear to have low vitamin C levels, there is no strong evidence from human studies that show vitamin C can treat lead toxicity. Vitamin C is a water-soluble vitamin that must be obtained from the diet or supplements. It has been linked to many impressive health benefits, such as boosting antioxidant levels, lowering blood pressure, protecting against gout attacks, improving iron absorption, boosting immunity, and reducing heart disease and dementia risk .Overall, vitamin C supplements are a great and simple way to boost your vitamin C intake if you struggle to get enough from your diet.
How much vitamin C is too much?
Since vitamin C is water-soluble and your body excretes excess amounts of it within a few hours after you consume it, it’s quite difficult to consume too much. In fact, it is nearly impossible for you to get too much vitamin C from your diet alone. In healthy people, any extra vitamin C consumed above the recommended daily amount simply gets flushed out of the body. To put it in perspective, you would need to consume 29 oranges or 13 bell peppers before your intake reached the tolerable upper limit. However, the risks of vitamin C overdose are higher when people take supplements, and it is possible to consume too much of the vitamin in some circumstances. For example, those with conditions that increase the risk of iron overload or are prone to kidney stones should be cautious with their vitamin C intake. All the adverse effects of vitamin C, including digestive distress and kidney stones, appear to occur when people take it in mega doses greater than 2,000 mg. If you choose to take a vitamin C supplement, it is best to choose one that contains no more than 100% of your daily needs. That’s 90 mg per day for men and 75 mg per day for women.