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5 Things You Don’t Know About Vitamin C

The hidden powers of vitamin C date back to 1935 and include treating kidney stones, chronic fatigue, and glaucoma

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Vitamin C has been both heralded and denounced as a cure for the common cold, and its overall effectiveness has been the subject of much debate. All told, the confusion has obscured its actual record of healing.

“Vitamin C research has been in place and very extensive since 1935, showing that it prevents and cures illnesses,” says Andrew Saul, PhD, an educator, author of bestselling books such as Doctor Yourself and Fire Your Doctor, and founder of

Although Linus Pauling, PhD, is arguably the most famous advocate of vitamin C, other pioneering scientists, as well as physicians, laid the groundwork by using the vitamin to cure or significantly improve the condition of seriously ill patients. Rather than taking a cookie-cutter approach, these doctors achieved dramatic recoveries by treating each patient individually, with customized oral or intravenous high dosages. These, says Saul, are some of the highlights that were published in scientific journals:

1. It Was Studied for Polio Prevention

1935: Claus Washington Jungeblut, MD, a professor at Columbia University in New York, reports that vitamin C prevents and cures polio, and inactivates diphtheria
and tetanus toxins.

2. Heart Disease Patients Need More 

1947: William J. McCormick, MD, in Toronto, Canada, shows that vitamin C is an antibiotic and antiviral that can prevent and/or treat many communicable illnesses, heart disease, and kidney stones. He finds that four out of five heart patients in hospitals are deficient in vitamin C.

3. It Boosts Healing for a Range of Illnesses—From Burns to Chronic Fatigue

1971: Frederick Robert Klenner, MD, in North Carolina, reports that high-dose, intravenous vitamin C dramatically helped patients with polio, pneumonia, other infectious diseases, bladder infections, arthritis, leukemia, atherosclerosis, ruptured discs in the spine, high cholesterol, corneal ulcers, diabetes, glaucoma, burns and secondary infections, heat stroke, radiation burns, heavy metal poisoning, chronic fatigue, and complications from surgery.

4. AIDS Patients May Benefit From More C

1981: Robert F. Cathcart, MD, in California, documents that oral vitamin C should be taken in doses up to “bowel tolerance” and later finds that it helps patients with AIDS.

5. IV Vitamin C Is Used in Cancer Patients

1995: Hugh D. Riordan, MD, in Kansas, describes successes in treating cancers with intravenous vitamin C during two decades of clinical practice.

Related: Scientifically Proven Benefits of Vitamin C

Everyone’s Ideal Dosage Is Different

Because clinical trials have not been able to consistently replicate the successful methods of these pioneering doctors, the curative power of vitamin C has been discounted, or even labeled as quackery. The reason may come down to customized dosages based on individual responses and symptoms.

Studies show that our needs for vitamin C skyrocket during times of illness or stress, notes Saul. As an example, some of Cathcart’s patients required 100 grams (100,000 milligrams) of vitamin C during a 24-hour period to reduce their most severe cold symptoms. And in those situations, such high doses did not produce the C-overdose side effect of diarrhea. Yet the same patients, when in good health, may have required little or no vitamin C supplementation.

Today’s placebo-controlled human trials, considered the gold standard, aren’t designed to evaluate this type of treatment, but typically test a pre-determined dosage on a large group of people. In addition, the dramatic results produced by vitamin C don’t mean that it is the only factor in disease, or that every ill person will benefit to the same degree.

Despite a lack of customized dosages, modern studies have begun to validate some of vitamin C’s benefits, including improved immune function, less risk or progression of heart disease and diabetes, reduced symptoms of allergic conditions, healthier gums, and younger-looking skin (vitamin C helps boost the body’s production of collagen). And customized, high-dose, intravenous vitamin C is beginning to be recognized in cancer treatment, especially as a way to improve the effectiveness of chemotherapy and reduce its side effects.

The Best Way to Use Vitamin C

Clinical experience shows that vitamin C is most effective when taken in doses up to “bowel tolerance,” which doesn’t necessarily mean diarrhea or loose stools. If you experience gas or a rumbling in your stomach, says Saul, you’ve reached bowel tolerance.

Equally important, he adds, “Take enough C to be symptom-free, whatever that amount may be.” It could take several days of high doses, or longer, for cold symptoms to subside.

In addition to pills or chewable forms, pure powdered vitamin C is another option. Powder typically provides 1,000 mg of C in one-quarter teaspoon, and mixes easily with water or juice. If you’re concerned about acidity, Saul recommends taking C with food, using a buffered form, or adding a tiny bit of sodium bicarbonate (baking soda) to your vitamin C powder. However, he says, “Normal stomach acid is 45–50 times as strong as vitamin C—if you can have vinegar on a salad, you can handle vitamin C acidity.” 

Liposomal vitamin C is thought by some to be better absorbed than other forms of vitamin C thanks to its unique phospholipid structure. The phospholipids protect the vitamin against damage that might happen during normal digestion. 

To find physicians who treat patients with vitamin C, visit