Vitamin C

Essential Micronutrient



Almost solely on its reputation to fight colds, Vitamin C has become the most widely used supplement. Yet, it’s what many don’t know about C that may help most — from fighting free radicals to promoting healthy joints. It’s clear this nutrient is more than just a cold fighter.

Other names for Vitamin C

ascorbic acid, L-ascorbic acid, ascorbate, acorbyl palmitate

Where to find Vitamin C

Vitamin C is abundant in citrus fruits, such as oranges, lemons, limes, tangerines, and grapefruits. Vegetables like red and green peppers, broccoli, tomatoes, asparagus, parsley, and dark leafy greens are also good food sources of C.

Note: Vitamin C is one of the least stable vitamins and is easily destroyed by cooking and processing.

Popup: Foods highest in Vitamin C

Daily Value

The Daily Value for Vitamin C is 60 mg.


Why athletes use Vitamin C

Intense physical exercise is great for your health, right? Well, of course. But what many people who exercise don’t realize is that the stress we place our bodies under is just that: stress. And not unlike the physical stress of illness, intense exercise can wreak havoc on the immune system, leading to an increase in infections.

That’s where Vitamin C steps in: it’s often used by athletes as part of a vitamin/mineral formula to counteract this stress — to help them remain optimally healthy, so they can stay active.

Ways that Vitamin C can enhance Muscle Gain & Recovery:
  • Help maintain a strong immume system during times of elevated stress, including intense exercise phases
  • Support the health of joints, tendons, and ligaments
  • Reduce inflammation, which may help lessen pain and stiffness following intense exercise
Ways that Vitamin C can enhance Longevity:
  • Detoxify the body to help reduce the side effects of some drugs and pollutants


Signs of Vitamin C deficiency

Deficiency of Vitamin C has been linked to:

  • Schizophrenia
  • Low body temperature
  • Gingivitis
  • Tooth decay
  • Excessive bleeding
  • Bruising
  • Fatigue/Weakness
  • Loss of appetite
  • Gastrointestinal disorders
  • Nosebleeds
  • Anemia
  • Bone and joint problems
  • Sexual dysfunction
  • Depression
  • Hypertension (high blood pressure)
  • Arthritis
  • Alcoholism
  • Ulcers
Potential uses for Vitamin C

Research indicates that Vitamin C may also be useful in the treatment of:

  • Common cold
  • Alcoholism
  • Exercise-induced asthma
  • Inflammation


More about Vitamin C

Vitamin C is water soluble (except for the acorbyl palmitate form) and is depleted more rapidly during times of both physical and emotional stress, which makes it vitally important to ensure that more than adequate amounts are being consumed daily.

Antioxidant/immune-boosting benefits

Almost unanimously, scientists and the general public alike agree that Vitamin C is one of the most important antioxidants. As a potent free-radical scavenger and immune booster, it’s used extensively to help prevent dangerous oxidation and combat colds and flus by helping increase the production of white blood cells.

That’s why many of us start sipping orange juice and eating our chewable C’s when even the slightest hint of a cold appears. And for good reason: clinical research has supported Vitamin C’s claims of helping reduce the length and severity of the common cold.

Vitamin C may also help decrease the production of histamine, which leads to watery eyes and a runny nose, and for that reason appears to be quite helpful for relieving not only cold symptoms but allergy symptoms as well.

Support healthy connective tissue

Because of its role in the formation and maintenance of collagen, Vitamin C is essential for strong connective tissue (namely, ligaments, cartilage, joints, skin, bones, and teeth). New research even suggests that increased amounts of C may help improve the integrity of joints in people with arthritis.

It also plays a key role in the growth and repair of many tissues, which may partially explain how it helps us recover more quickly from intense training. In one recent study, exercisers who consumed just 200 mg of Vitamin C 2 times daily enjoyed reductions in muscle soreness and improved muscle function. The authors of the study concluded: “prolonged Vitamin C supplementation has some modest beneficial effects on recovery from unaccustomed exercise.” Also important to note is Vitamin C’s potential to reduce inflammation and keep mild pain and stiffness to a minimum following strenuous activity.

Disease-fighting potential

More recently, experts have begun suggesting Vitamin C may help combat cancer-causing agents because it appears to inhibit the production of nitrosamines; thus, C may prevent the oxidation of cholesterol.

Vitamin C also plays a vital role in protecting the body from LDL (“bad”) cholesterol, as well as lowering blood triglycerides and total cholesterol levels. This, along with its immune-boosting benefits, may help improve heart health and reduce the formation of blood clots.

One of Vitamin C’s most interesting properties is its ability to regenerate newly oxidized Vitamins A and E and possibly some of the other antioxidants in the body, helping support their effects — giving the body yet another advantage when fighting free radicals.

Vitamin C also appears to help relieve exercise-induced asthma. In one study of 20 athletes, 9 of the athletes’ asthma symptoms were completely eliminated after one week’s supplementation with 2 grams of Vitamin C. Vitamin C’s potential benefits for asthma appear to be even more effective when it’s supplemented with magnesium.

Greater needs for C

There are certainly some situations when it appears extra Vitamin C supplementation could be even more prudent.

Pollution, for example, has been shown to increase free radicals, so people who live in or around larger cities could benefit from additional daily doses. And the self-destructive so-called “recreational activities” of cigarette smoking (even second-hand) and alcohol use have been shown to increase the number of free radicals. So smokers and drinkers could go for a much needed extra dose of this essential nutrient.

Aging adds an entirely new dimension to physical and mental stress. As people age, their needs for Vitamin C increase because part of the aging process again includes a greater amount of free radicals wreaking havoc throughout the body. Like other antioxidants, Vitamin C may be an effective weapon for fighting the aging process — possibly extending years of active life.

In addition, people preparing to undergo some types of surgery or recovery programs may want to boost their intakes of C because it appears to help the body fight infection, which may support healing after surgery and help the body cope with the added stress of surgery. One exception is when rapid healing is undesirable. For example, certain plastic surgery procedures require a slower rate of healing to prevent excess scar tissue from forming.

In conclusion

Vitamin C, with its handful of benefits, has, without a doubt, earned its reputation as one of the “most important antioxidants.” From fighting free radicals to its role in promoting healthy joints to its cancer-fighting success, it’s clear this essential nutrient is much more than just a cold fighter.



The amounts recommended vary more for Vitamin C than for any other nutrient, but many sports nutrition experts agree that between two and four grams per day may be beneficial for active individuals.

Linus Pauling, a world-renowned scientist, humanitarian, educator, and health proponent, suggested optimal daily intakes are between two and nine grams. (Dr. Pauling was also the only recipient of two unshared Nobel Prizes. In 1970, he wrote what became the national best-selling book Vitamin C and the Common Cold, which is what originally brought public attention and increasing demand for this vitamin. Later, he published two other popular books and a stack of scientific and popular papers on nutrition.)

Sports nutrition expert Dr. Michael Colgan recommends up to 12 grams per day for athletes, depending on bodyweight, activity levels, and other factors.


Because Vitamin C is rapidly absorbed by the body and used within about two hours, it may be best to take it in divided amounts throughout the day at about four-hour intervals with food.

Synergists of Vitamin C

Vitamin E and Vitamin C may work together synergistically, reinforcing each other’s antioxidant abilities.

Recent research combined Vitamin E (500 mg per day), beta-carotene (30 mg per day) for 90 days and added Vitamin C (1 gram per day) for just the last 15 days and found dramatic improvements in the athletes’ antioxidant defenses. In fact, this antioxidant combination was found to enhance the antioxidant enzyme activity of superoxide dismutase (SOD) dramatically.

Benefits of Vitamin C may be enhanced when taken as part of a complete antioxidant formula.

Some experts suggest that rose hips Vitamin C, which contains certain bioflavonoids and other enzymes, may help Vitamin C assimilate in the body.

Hesperidin, a bioflavonoid, may increase Vitamin C’s free-radical-scavenging abilities.

Safety of Vitamin C

Diarrhea and stomach upset may occur when large amounts (over 5,000 mg) of the ascorbic acid form are taken at one time. This is called “bowel tolerance” and indicates your body has had enough.

If you are pregnant, no more than 5,000 mg per day is recommended.

Toxicity of Vitamin C

No known toxicity.

Bans and restrictions

None reported.


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