Vitamin C has no known toxicity. That means you won’t get Vitamin C poisoning. But, depending on the type of Vitamin C you take, you may have a different answer for the “how much Vitamin C should I take?” question. Your body has two primary mechanisms for helping determine your need for Vitamin C. Although far from perfect, these mechanisms are a good starting point to figure out how much Vitamin C you should take.

The Bowel Tolerance Test determines how much Vitamin C to take

People who have used high doses of traditional Vitamin C often experience a watery diarrhea, called a C-flush. This phenomenon happens whenever a large amount of Vitamin C is not absorbed in the small intestine. The unabsorbed Vitamin C reaches the colon where it draws water into the bowels. At the point of bowel tolerance, a watery diarrhea naturally ensues.

This is not an adverse side effect; it happens because the intestines can’t handle the volume of water the Vitamin C draws into the large bowel. The Vitamin C dosage that initiates a C-flush is referred to as a “bowel tolerance” dosage.

Daily bowel tolerance dosing to determine your current need for Vitamin C can be inconvenient and unpleasant, but a good strategy includes periodic utilization of this type of Vitamin C supplementation. Once a month, or even once a week, take spaced doses of Vitamin C powder dissolved in water until the onset of diarrhea. At this point you can determine a baseline dose, and the bowels will benefit from a healthy cleanse.

Please note: Since the liposome formulation enjoys superior absorption, it will not cause a diarrheal flush, so liposomal Vitamin C is not appropriate for this test.

The results could establish a Vitamin C dosage that’s right for you 

When you establish the baseline requirement, supplementation on subsequent days could include a combination of a liposomal formulation and sodium ascorbate powder or either type alone. Because liposome-encapsulated Vitamin C — like our Lypo-Spheric® Vitamin C — has superior absorption than other oral forms, especially as dose sizes increase, the following substitution schedule provides approximate values:

• 1,000 mg liposomal = 3,000–4,000 mg powder

• 2,000 mg liposomal = 8,000–10,000 mg powder

• 3,000 mg liposomal = 12,000–18,000 mg powder

Keep in mind that the presence of a toxic or pathogenic challenge often increases bowel tolerance for Vitamin C, most often in proportion to the severity of the challenge. In fact, Robert Cathcart, MD, noted that with certain patients, bowel tolerance frequently rose to 75–100 grams per day.

The total daily dosage should be at least as much as determined by the last bowel tolerance result. Additional amounts often provide increased benefit.

Several forms of Vitamin C will induce a C-flush:

  • Ascorbic acid powder is the least expensive form of Vitamin C — because it is an acid, it is more likely to cause digestive stress.
  • Sodium ascorbate powder is safe and easy to use — preferred over all other non-liposomal forms.
  • Ascorbyl palmitate is a fat-soluble form of Vitamin C, which gives a different absorption characteristic.
  • Bioflavonoids are good antioxidant nutrients — although they can help Vitamin C improve the antioxidant capacity of the body, they are not necessary for the C-flush experiment.
  • Calcium ascorbate may slightly improve absorption, but high doses can introduce excessive amounts of calcium into the body.
  • Mineral forms — chromium ascorbate, magnesium ascorbate, manganese ascorbate, molybdenum ascorbate, potassium ascorbate, and zinc ascorbate — present a problem because the associated minerals bring toxicities of their own when used in the high dosages that you want to reach with your Vitamin C supplementation. Avoid them except in lower doses.
  • Pills and capsules often contain non-nutritive fillers and ingredients that can add expense and adversely affect absorption. Also, liquid and chewable formulations may contain sugar. Avoid them if possible.

A better way to absorb vitamin c. Carton of Lypo-Spheric Vitamin C. Buy now button

Experimental dosage can help to determine how much Vitamin C to take

Another way to determine an optimum dose is simply by evaluation of bodily signals. When you don’t “feel quite right,” an increase in dose will usually be in order. If you reach a sense of well-being and additional Vitamin C doesn’t produce any further improvement, the body’s need has most likely been met.

Content Adapted from Primal Panacea by Thomas E. Levy, MD, JD.