Do I Need a Vitamin C Supplement?

Vitamin C is an essential part of the diet. You should be able to get enough if you are healthy and eat a variety of fresh fruits and vegetables.

Your clients may wonder if they need a supplement. Educate them about the role of vitamin C in health and physical activity and make sure they consult their doctors before trying any dietary supplement.

What is Vitamin C?

Vitamin C is a water-soluble vitamin and micronutrient also known as ascorbic acid. You can find vitamin C in many foods. You can also get it as a supplement and in some fortified foods.

Humans must take in vitamin C through the foods they eat. We cannot make this nutrient, although other animals can. Because it’s water-soluble, excess vitamin C is excreted in urine and cannot be stored. The recommended daily vitamin C intake amounts for adults are:

• Adult men – 90 milligrams (mg)

• Adult women – 75 mg

• Pregnant women – 85 mg

• Lactating women – 120 mg

Smokers need an additional 35 mg of vitamin C daily. Oxidative stress from smoking, even secondhand smoke, lowers levels of vitamin C in the body.

Vitamin C Functions and Food Sources

Vitamin C is an essential micronutrient. We need it to function normally. For instance, vitamin C is a component of collagen, necessary for building and maintaining strong connective tissue, skin, muscles, and blood vessels.

Vitamin C is an antioxidant and protects cells from damage caused by free radicals. In this role, vitamin C is important for reducing the risk of heart disease and cancer. Vitamin C supports the immune system, helping wounds heal and the body fight infections.

All fresh foods have some vitamin C, even meat. The best sources are fruits and vegetables, especially citrus fruit, bell peppers, strawberries, tomatoes, guava, acerola cherry, kiwi, papaya, and cruciferous vegetables (broccoli, cauliflower, cabbage, and Brussels sprouts). Cooking these foods destroys some vitamin C, so fresh and raw is best.

Is There Such a Thing as a Vitamin C Deficiency?

Vitamin C deficiency is called scurvy. Most often associated with previous centuries and seafaring individuals, scurvy occurs more often than you might think. With access to a variety of fresh foods, scurvy is rare. Risk factors for vitamin C deficiency include:

• Smoking

• Alcohol use disorder

• Poor diet, especially lack of fruits and vegetables

• Restrictive diets

• Eating disorders

• Type I diabetes

• Gastrointestinal conditions

• Dialysis

Scurvy is rare but not non-existent. Even in the developed world, researchers estimated it occurred in 10% to 14% of adults as recently as the 1990s.

Vitamin C deficiency is simple to treat by increasing intake. You can catch signs early to reverse them:

• Rough, dry, damaged, and sensitive skin

• Blood around hair follicles

• Concave fingernails with red spots

• Bruising readily

• Slow healing from wounds

• Painful joints

• Bleeding gums

• Loose teeth

• Getting sick frequently

• Fatigue

• Weight gain

Are There Any Benefits to Taking Vitamin C Supplements?

Most people don’t need a vitamin C supplement. If you or a client eat a healthy, well-rounded diet and don’t have medical conditions that put you at risk, you should get enough from food. Even so, there may be some benefits to adding extra vitamin C to your diet.

Many of your clients may also wonder about a multivitamin supplement. Learn more with this post on multivitamins and if they’re necessary with a healthy diet.

Vitamin C Boosts Immunity

This is one of the most common reasons people supplement vitamin C, especially during cold and flu season. It’s a misconception that vitamin C can prevent the common cold. However, it does support the immune system.

Vitamin C plays a role in producing white blood cells and helping these immune cells function. Research indicates that a vitamin C supplement can speed wound healing and that people who are sick with infections have lower levels of vitamin C.

Boost your immune system naturally with these power foods.

Vitamin C for Heart Health

As an antioxidant, vitamin C repairs damage caused by free radicals. The accumulation of free radicals in the body causes oxidative stress, which can increase inflammation and the risk of chronic diseases, including heart disease.

Studies also indicate that a vitamin C supplement can lower blood pressure in people with normal and high blood pressure. Another study looked at cholesterol and triglycerides. People who took 500 mg or more of vitamin C per day had lower levels in their blood. All of this together provides compelling evidence for the role of vitamin C in lowering heart disease risk.

Prevent Iron Deficiency with Vitamin C

Iron is another essential nutrient. It carries oxygen throughout the blood to tissues that use it for energy. Everyone needs adequate iron. Low levels of iron or low iron absorption causes anemia.

Vitamin C aids the absorption of iron. You don’t need a C supplement if your iron levels are normal. However, supplementing with both iron and vitamin C may help if you struggle with anemia. People at risk for iron deficiency are those with poor diets, pregnant women, all women of child-bearing age, older adults, and teenagers going through rapid growth spurts.

If you have clients on a vegan or vegetarian diet, they could also be at risk for iron deficiency. Talk to them about finding iron-rich plant-based foods.

Boost Brain Power

As an antioxidant, vitamin C is essential for brain health, memory, and cognition. Oxidative stress and inflammation in the brain may be causal factors in age-related brain diseases like dementia. There is some evidence that supplementing with vitamin C can boost cognition and memory and reduce the risk of dementia and Alzheimer’s disease.

Vitamin C for Athletic Performance and Recovery

Some people think that high doses of vitamin C will improve athletic performance, but no evidence from research backs this assumption. Studies have looked at oxygen uptake, heart rate after exercise, and performance in competitive sports and found no benefit from vitamin C.

However, these studies show that athletes with poor diets or other factors leading to low vitamin C levels perform sub-optimally. A supplement may help someone, but a healthier diet is a better option.

Recovery from exercise may be another story. Vitamin C is an antioxidant, so it may speed the repair of oxidative damage after a workout session or sports event. Studies of supplementing vitamin C do show some promise for aiding recovery.

For instance, in one study, athletes receiving vitamin C and vitamin E supplements together had fewer markers of muscle damage than control athletes. Another study found five or more servings of vitamin C-rich fruits and vegetables reduced oxidative stress after athletic performance.

Safety and Risks of Vitamin C Supplements

Because it dissolves in water, it is difficult to overdose on vitamin C. Excess amounts get excreted in the urine rather than absorbed. However, it is always possible to overdo it. Taking more than 3,000 mg of vitamin C per day may cause diarrhea, headaches, stomach cramps, heartburn, and fatigue. It can also contribute to and worsen some existing conditions: kidney stones, iron overload, and gout.

There is also evidence that a high dose can turn vitamin C from an antioxidant to a pro-oxidant. In other words, too much vitamin C can damage cells and tissues.

Supplementing with vitamin C is generally low-risk, but it is also unnecessary for most people. If you have clients concerned about their vitamin C levels, have them talk to their doctors about it. Otherwise, a healthy, varied diet in fresh foods should be enough to keep C levels high and athletic performance optimal.

A Nutrition Certification from ISSA can help you turn your passion for diet and food into a real career. Learn about nutrition, dietary supplements, health, and motivating and coaching clients at your own pace.

References

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