4 Ways Taking a Vitamin C Supplement Can Boost Your Health

Vitamin C is a popular antioxidant, known largely for its immune health benefits. Many people take vitamin C supplements to prevent illness, especially during cold and flu season.

While boosting your immunity is one role of vitamin C, there are a few other lesser-known benefits of this essential vitamin. Learn what those are below, along with quality sources of vitamin C.

Some of the hallmark signs of a vitamin C deficiency are delayed wound healing and fragile skin. The main reason that vitamin C is so critical for skin health is because of its relationship to collagen. Collagen is a key component of connective tissue, and vitamin C is necessary for collagen formation. So, when you don’t consume enough vitamin C, collagen deteriorates which leaves your skin in bad shape.

Vitamin C also works with vitamin E, another antioxidant, to prevent damage to your skin from harmful UV rays. 

Vitamin C’s role in skin health also has immune benefits, as the skin is one of our body’s defense systems against pathogens. However, it doesn’t end there. Vitamin C also plays a role in both innate and adaptive immunity, our bodies’ first response and targeted response to specific pathogens, respectively. Vitamin C’s antioxidant properties prevent oxidative damage to healthy cells. 

Specifically in athletes, those exposed to extreme cold temperatures, and those on the border of vitamin C deficiency, consuming at least 200 mg of vitamin C per day may reduce risk of the common cold. For the general population, vitamin C supplementation hasn’t been shown to prevent the common cold, but it may reduce the duration of illness and severity of symptoms if taken preventatively (as opposed to after development of the cold).

Since oxidative damage— what occurs in your body when there are too many unstable molecules called free radicals in the body and not enough antioxidants to get rid of them—is thought to be a cause of cardiovascular disease, antioxidants like vitamin C may help reduce risk of cardiovascular disease. A 2020 study found that vitamin C supplementation of at least 500 mg per day was linked with reduced blood pressure levels. 

However, many other studies have found conflicting results on vitamin C’s role in reducing cardiovascular disease risk, so more studies are necessary to further explore this connection.

Vitamin C plays an important role in enhancing absorption of nonheme iron, the kind that comes from plant foods. If you’re at risk of iron deficiency, especially if you eat a plant-based diet, adding sources of vitamin C to your meals could help you better absorb the iron in foods like beans, seeds, and nuts. That might mean adding red peppers to your beans or having oatmeal with nuts, seeds, and strawberries.

While supplementation is one way of getting vitamin C, there are several great food sources as well. You’ll notice that they’re all fruits and veggies, so in addition to vitamin C, they have a bunch of other nutrients important for health. 

Some vitamin C-rich foods include:

Red bell pepper: 95 milligrams (mg) per ½ raw cup, or 106% of your daily value (DV)
Orange juice: 93 mg per ¾ cup, or 103% DV
Orange: 70 mg per medium orange, or 78% DV
Grapefruit juice: 70 mg per ¾ cup, or 78% DV
Kiwi: 64 mg per medium kiwi, or 71% DV
Green bell pepper: 60 mg per ½ raw cup, or 67% DV
Broccoli: 51 mg per ½ cooked cup, or 57% DV
Strawberries: 49 mg per ½ sliced cup, or 54% DV
Brussels sprouts: 48 mg per ½ cooked cup, or 53% DV
Baked potato: 17 mg per medium potato, or 19% DV

Supplements are another means of meeting your vitamin C needs. These come in a variety of forms including capsule, powder, gummy, chewable, and liquid. 

Vitamin C can be taken any time of day, but spreading it out or taking it with food may reduce the likelihood of gastrointestinal side effects caused by its high acidity level. 

What To Look for

When buying a supplement, we recommend finding an independently-tested option since supplements are not regulated by the FDA for purity and potency. Reputable independent testers include USP, NSF, and ConsumerLab.com. When in doubt, shop from reputable brands and always speak with a healthcare provider before starting a new supplement.

Dosage

The recommended dietary allowances (RDAs) for vitamin C vary based on age, sex, pregnancy or lactation status, and smoking status. The RDAs for vitamin C (specifically from food sources) are:

0-6 months: 40 mg7-12 months: 50 mg1-3 years: 15 mg4-8 years: 25 mg9-13 years: 45 mg14-18 years: 75 mg for males; 65 mg for females; 80 mg if pregnant; 115 mg if lactating19+ years: 90 mg for males; 75 mg for females; 85 mg if pregnant; 120 mg if lactating

Studies have shown that when you consume 30-180 mg per day, 70-90% is absorbed, but when you consume upwards of 1g/day, less than 50% is absorbed.

Since vitamin C is a water-soluble vitamin, there is a low risk of toxicity. When you consume too much of it, your body typically excretes the excess in your urine rather than holding on to it. 

Some studies have suggested that excess intake of vitamin C could contribute to other health issues like increased risk for cardiovascular disease mortality, excess iron absorption, increased oxidative damage, and higher risk of kidney stones; however, these studies were mostly inconclusive or done in vitro–on test tubes–rather than on actual people. For iron absorption, the issue was only seen in those with hereditary hemochromatosis.

If you are undergoing chemotherapy or radiation treatment or taking statins, it’s recommended you check with a healthcare provider before taking a vitamin C supplement. 

Vitamin C supplements should typically be avoided if you’re undergoing chemotherapy or radiation treatment. Studies are mixed on the effects of supplemental forms of antioxidants–like vitamin C–on cancer treatment and tumor progression. Therefore, if you’re undergoing these forms of cancer treatment make sure to speak with your oncologist before starting a vitamin C supplement. 

If you’re taking a statin–a type of drug typically used to lower cholesterol levels–you may also want to hold off on a vitamin C supplement. Vitamin C may reduce the effectiveness of statins by minimizing their positive impact on HDL cholesterol levels–the “good” kind of cholesterol. Check with your doctor before starting a vitamin C supplement if you’re taking a statin.

While vitamin C toxicity is rare, there are established tolerable upper limits (ULs) that apply to food and supplemental forms of vitamin C. The ULs vary based on age and are as follows:

1-3 years: 400 mg4-8 years: 650 mg9-13 years: 1200 mg14-18 years: 1800 mg19+ years: 2000 mg

While vitamin C is generally safe, some side effects can occur from excess vitamin C consumption. This is most common through supplementation since supplements tend to have much higher concentrations of vitamins than foods do. 

Potential side effects include:

Vitamin C is a powerful antioxidant and water-soluble vitamin. It plays an important role in skin health by helping with collagen synthesis and protecting against damage from UV rays. It also promotes immune health, iron absorption, and may even reduce risk for cardiovascular disease. 

Consuming vitamin C-rich foods is generally safe, but supplementation may be risky for those taking statins or undergoing chemotherapy or radiation treatment. In general, it’s best to speak with a trusted healthcare provider before starting a new supplement.