Vitamin C: Cancer Cure? Fountain of Youth?

Moms around the world know that vitamin C is good for their kids, and now medical science is catching on.

Vitamin C is an antioxidant; therefore, one of its primary known benefits is the neutralizing of cell damaging free radicals. Free radical damage to cells can lead to cancer, other serious diseases, wrinkles, premature aging and perhaps gray hair.

There is much confusion about the proper dosage of vitamin C. The U.S. Food and Drug Administration Daily Reference Value (DRV) currently is 60 mg based on a 2000 calorie intake for adults and children four years old or older. The National Academy of Sciences Food and Nutrition Board publish their own dietary guidelines and recommend 90 mg for males 19 and older and 75 mg for females 19 and older. The USRDA for smokers 19 years and older is 125 mg for men and 110 mg for women. These are miniscule amounts compared to those recommended by some researchers. Nobel Prize winning quantum chemist and biochemist Linus Pauling reported taking 18,000 mg of vitamin C per day and attributed his longevity to it; he survived years even after he was diagnosed with prostate cancer.

If one follows the USDA and National Cancer Institute recommendations of five servings of fruits and vegetables a day, one could easily obtain 200 mg of vitamin C or more per day through dietary staples.

Many animals produce large amounts of vitamin C daily and will up the production tremendously if sick or stressed. Humans are one of the few organisms that need vitamin C for life but who cannot manufacture it in the body. We must obtain our vitamin C from diet and supplements. We also cannot store vitamin C and therefore must consume it frequently to make sure plenty is available for our body's use.

Anti-Aging Benefits

The primary benefit of vitamin C is in its antioxidant properties. Our cells are under constant bombardment by free radicals. Vitamin C protects you from free radical assaults.

Chemoprevention may be another benefit of vitamin C. Chemoprevention is the use of natural or synthetic substances for reducing the risk of cancer. Ray Kurzweil, in his book Fantastic Voyage (co-authored with Terry Grossman, M.D.),idicated that their program suggested that grown-ups should injest 2 grams of vitamin C dailyl for chemoprevention.

It is clear that many experts believe taking much higher doses of vitamin C than the Food and Drug Administration's RDI is beneficial to health. Each individual has different needs, so be sure to consult a doctor or other medical professional to assess what your individual needs are.

Taking aspirin and smoking can deplete vitamin C stores.

Studies show that aspirin may impede gastrointestinal absorption of vitamin C. However, studies also show that during infection of the common cold, aspirin seems to increase the amount of vitamin C available to cells.

It is especially beneficial for smokers to take extra vitamin C because there is research to indicate that vitamin C may help protect against some of the free radical damage caused by smoking. Taking extra vitamin C does not substitute for quitting smoking, but it could help for those who find it difficult to quit.

You can get vitamin C in orange juice (from concentrate), citrus fruits such as oranges, lemons and limes, red bell peppers and a variety of other fresh fruits and vegetables. You can get additional vitamin C from supplements. If vitamin C irritates your stomach, you may also look for "buffered" vitamin C tablets or liquid vitamin C.

Table: Comparing Dietary Sources of Vitamin C

Guava, raw, ½ cup
188 mg

Red sweet pepper, raw, ½ cup
142 mg

Red sweet pepper, cooked, ½ cup
116 mg

Kiwi fruit, 1 medium
70 mg

Orange, raw, 1 medium
70 mg

Orange juice, ¾ cup
61-93 mg

Green pepper, sweet, raw, ½ cup
60 mg

Green pepper, sweet, cooked, ½ cup 51 mg

Grapefruit juice, ¾ cup
50-70 mg

Vegetable juice cocktail, ¾ cup
50 mg

Strawberries, raw, ½ cup 49 mg

Brussels sprouts, cooked, ½ cup
48 mg

Cantaloupe, ¼ medium 47 mg

Papaya, raw, ¼ medium 47 mg

Kohlrabi, cooked, ½ cup
45 mg

Broccoli, raw, ½ cup
39 mg

Edible pod peas, cooked, ½ cup 38 mg

Broccoli, cooked, ½ cup
37 mg

Sweet potato, canned, ½ cup 34 mg

Tomato juice, ¾ cup 33 mg

Cauliflower, cooked, ½ cup 28 mg

Pineapple, raw, ½ cup 28 mg

Kale, cooked, ½ cup 27 mg

Mango, ½ cup 23 mg

Source: Nutrient values from Agricultural Research Service (ARS)
Nutrient Database for Standard Reference, Release 17.