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Ask the Naturopathic Doctor

“C” for Yourself

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Q: If you were stranded on a desert island and could have only one supplement with you, what would you choose?

—Jade L., Bakersfield, Calif.

Ihave no doubt about what I’d choose. It is essential to immune function. Humans don’t produce it, and our adrenal glands require massive amounts when under stress. We can get enough from our diet to prevent scurvy, but we need to ingest much more for optimal tissue repair and graceful aging. Of course, it’s vitamin C, or ascorbic acid.

Vital Nutrient

Most mammals, when stressed, injured, or diseased, convert glucose to vitamin C for the purposes of adrenal support, tissue repair, and white blood cell (phagocyte) effectiveness. But because the human body can’t process this conversion, we need plenty of C in our diets. Relatively small doses are required for our day-to-day needs—maybe as low as the RDA of 65 mg—so that we don’t get scurvy. But higher doses are required to ward off or fight other ailments.

Many modern diseases fulminate under the ravages of inflammation, where damage is happening too fast for our natural repair mechanisms to handle. Vitamin C works to hasten the resolution of many such conditions—from colds to cancers to burns—by donating high-energy electrons to neutralize the free radicals that are the harbingers of inflammation.

Vitamin C is also essential for the production of collagen, a substance found in all tissues in the body, and norepinephrine, which can be thought of as a souped-up version of epinephrine, the neurohormone that triggers the fight-or-flight response to danger. Vitamin C is also found in the body in high concentrations in white blood cells and the adrenal glands.

Getting Enough

Vitamin C requirements increase significantly under all forms of physical, mental, and emotional stress. Reams of published research attest to the healing properties of vitamin C in human diseases, including asthma, atherosclerosis, cancer, diabetes, high triglycerides, Parkinson’s disease, pre-eclampsia, and ulcers. Most research concurs that vitamin C significantly reduces death rates from all causes.

When you’re healthy, eating a high-fiber, high-veggie diet, your body is less stressed, and your vitamin C requirements relax. High doses (above 4–5 grams daily) given to a healthy person typically produce looser stools. But researcher Robert Cathcart, MD, provides good evidence that the sicker or more toxic people are, the more vitamin C they can absorb without diarrhea. When a person is ill, or requires additional nutrition for tissue repair, amounts up to 100 grams of vitamin C can be absorbed within a 24-hour period.

Contrary to popular belief, vitamin C does not cause kidney stones, unless you are a dialysis patient, in which case the possibility of kidney stones with high levels of any nutrient will increase. There are no known adverse interactions with vitamin C and any drug or supplement.

The Best Sources

Vitamin C can be found in citrus fruits and berries. The highest berry source is the acerola cherry. It takes about 25 cherries to get 2,000 mg (2 grams) of vitamin C. A 6-ounce glass of orange juice contains less than 100 mg of vitamin C. Vegetables relatively high in vitamin C include broccoli, peppers, potatoes, and Brussels sprouts. When taken from food sources, fresh is best because vitamin C levels in fruits and veggies diminish within a few hours of being exposed to the air.

In supplements, most available vitamin C is derived from corn (no DNA is involved, so GMO is not an issue). Supplements of C can also be sourced from sago palm or tapioca (cassava). Many brands add bioflavonoids, which increase the absorption of ascorbic acid. I prefer powders made in a lab under controlled methodology because they are much more stable—with a nearly indefinite shelf life.

I have worked up to taking about 5 grams of vitamin C daily, and if I were to fall ill, I would take more until my stools become loose. I advise using a buffered product that contains added alkalinizing minerals, which is easier on the stomach, and absorbs better when taken orally. For those who are really ill and require massive doses, the intravenous method is more effective.

Interested in vitamin C research?

Look for information from the following experts: Linus Pauling, PhD (; Irwin Stone, PhD (; and Robert Cathcart, MD (

Acerola cherries are an excellent source of vitamin C.