Buffered C Crystals

Vitamin C is an essential, water-soluble vitamin that is a powerful antioxidant, as well as a metabolic co-factor in many body processes. Vitamin C first gained fame for the prevention of scurvy,*1 the oldest known nutritional deficiency disease; ascorbic acid, another name for vitamin C, literally means “without scurvy.”

Guarding Against Free Radicals

As an antioxidant, vitamin C protects the water-based areas of the body, such as the blood, lymph fluid, and the areas within and between the cells, from free-radical damage.*2 Free radicals are highly reactive compounds formed by radiation; found in air pollution, ozone, and cigarette smoke; consumed in rancid fats; and produced during certain normal body processes. Peroxides and superoxides are examples of free radicals frequently present in the body. If left unchecked, free radicals damage cell membranes, proteins, and nucleic acids (which comprise the genetic code within each cell).3

The antioxidant capability of vitamin C is impressive, and antioxidant experts note that vitamin C is “...probably the most effective, least toxic antioxidant identified in mammalian systems.”*4 Vitamin C also supports the body’s antioxidant defenses by recycling the vitamin E radical (produced when vitamin E neutralizes free radicals) back to its functional form.*5

Cell Support

Another major role of vitamin C is the formation and manufacture of collagen.*6 Collagen, a protein that forms the basis of connective tissue, acts as a cementing substance between cells and is found in bones, tendons, muscles, skin, gums, joints, and other tissues.

Immune Support

Vitamin C helps support the immune system.*7 Vitamin C also helps increase the body’s resistance to damaging invasions of bacteria and viruses.*8, 9 Larger doses (i.e., 1 to 8 grams/day) taken early during an “invasion” of bacteria or viruses supports immune function even more during these times of greater stress.10 A combination of antioxidant vitamin C and bioflavonoids also helps reduce the damaging affects of trama.*11

Nature’s Life Bioflavonoid Complex concentrate contains 50% active flavonoids—the highest concentration sold. Dietary supplement labels from other companies can be misleading as to the quantity of active flavonoids, since some appear to contain 100% active flavonoids, when in reality they may contain as little as 5%. Nature’s Life products contain unadulterated Testlabs® 50% active true bioflavonoids.

What’s the Best Amount?

Although it only takes about 10 mg of vitamin C each day to keep scurvy at bay,* many doctors believe that much more than this amount is necessary to ensure good health.31 The Recommended Dietary Allowance (RDA) for vitamin C is:

Infants

• 0-0.5 year . . . . . . . . . . 30 mg

• 0.5-1 year . . . . . . . . . . 35 mg

Children

• 1-3 years . . . . . . . . . . 40 mg

• 4-10 years . . . . . . . . . . 45 mg

• 11-14 years . . . . . . . . . . 50 mg

Adults

• 15+ years . . . . . . . . . . 60 mg

• Pregnant . . . . . . . . . . 70 mg

• Lactating (1st 6 mo.) . . . . . . . . . . 95 mg

• Lactating (2nd 6 mo.) . . . . . . . . . . 90 mg

• Cigarette Smokers . . . . . . . . . . 100 mg

The current RDA recognizes the effect of lifestyle on vitamin C status, as demonstrated by the higher intake recommended for smokers. However, research demonstrates that vitamin C requirements increase significantly beyond the RDA level for adults during times of stress, injury or invasion by bacteria and viruses or use of alcohol or caffeine.*32

Most animals do not require a dietary source of vitamin C, since they can manufacture this vitamin in their bodies. Humans are an exception—(we are one of only a handful of mammals that cannot produce our own vitamin C) and consequently we are dependent on a daily dietary source of this vitamin. Using data from animal studies, an average-size adult would need to consume 1.75 to 3.5 grams of vitamin C daily to equal the amount produced by many other animals.33

In order to clarify the requirement for vitamin C, one research study examined vitamin C absorption and excretion in a group of healthy, adult men.34 Daily intake of 200 mg was required to reach 100% bioavailability. Vitamin C at the highest intake level tested (2,500 mg) caused no adverse effects. On the other hand, even a marginal deficiency of vitamin C resulted in feelings of fatigue and irritability in the subjects.

The Alliance for Aging Research, a national health organization comprised of leading scientific researchers, also recommends a vitamin C intake significantly higher than the RDA. This organization suggests vitamin C intake to range from 250 to 1,000 mg.35 Because vitamin C is water-soluble, it is not stored in the body for long-term use. Consequently, taking vitamin C several times throughout the day (as opposed to only once) should enhance the body’s access to this vitamin. Sustained release forms of vitamin C supplements may also enhance the body’s access to vitamin C.36 Vitamin C is found in a wide variety of fruits and vegetables. However, even popular food sources of vitamin C (such as an orange or a serving of strawberries) only provide about 60 mg (the RDA) of this vitamin.

Different Forms of Vitamin C

Vitamin C is a well absorbed nutrient—80%-90% of the vitamin C from foods is absorbed.37 Dietary supplements of vitamin C are also well absorbed and tolerated by the body.37

Buffered forms of vitamin C, such as the calcium ascorbate provided in several Nature’s Life formulas, reduce the acidity of vitamin C, which lessens the potential for stomach upset.

One form of vitamin C not used by Nature’s Life are “esterfied” mineral ascorbates, because these forms have not been shown to have an advantage in peer-reviewed human studies that would justify their increased cost. A recent double-blind study compared the bioavailability of regular vitamin C (ascorbic acid), vitamin C with bioflavonoids, and Ester-C®.†38 The ascorbic acid and ascorbic acid with bioflavonoids were found to be equal to or superior to the Ester-C®† form of vitamin C.38

A common myth is that hypoallergenic vitamin C supplements are “special.” In actuality, all vitamin C is hypoallergenic, because allergies to vitamin C do not exist. Vitamin C is manufactured from any starchy food such as corn, potatoes, rice or sugar beets. No manufacturer tracks the source of vitamin C from the food to finished ascorbic acid—because there is no difference in the final product. Regardless of the original food source, the ascorbic acid vitamin C used in most dietary supplements is purified, meaning that no traces of the food source will remain in the final product. (Note: allergies do exist to many foods rich in vitamin C and bioflavonoids such as oranges or grapefruit.)

Confirmation of Safety

Vitamin C intake of ten to one hundred times the RDA of 60 mg are very common in the United States and is not generally associated with adverse effects.39 Several reviews of vitamin safety report that even prolonged, high intakes of vitamin C are generally without adverse effects.40 Although rare, the most likely adverse effect reported for high vitamin C intake (several grams daily) is gastrointestinal upset, such as nausea, abdominal cramps, and diarrhea.41

“Conditioned scurvy,” in which the cessation of high vitamin C intake prompts scurvy symptoms has been theorized to exist. However, a detailed review of the published evidence suggests that there is not a factual basis for this hypothetical phenomenon.41

Nature’s Life Vitamin C

Vitamin C is essential to sustain life and maintain a healthy body. This antioxidant nutrient also neutralizes free radicals to delay or prevent damage to cells. Nature’s Life provides high quality vitamin C products in several forms — something for everyone!

References

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2. Glascott PA, Tsyganskaya M, Gilfor E, et al. The antioxidant function of the physiological content of vitamin C. Mol Pharm 1996;50:994-999.

3. Ames BN, Shigenaga MK, and Hagen TM. Oxidants, antioxidants, and the degenerative diseases of aging. Proc Natl Acad Sci USA 1993;90:7915-7922.

4. Sauberlich HE. Pharmacology of vitamin C. Ann Rev Nutr 1994;14:371-391.

5. Chan AC. Partners in defense, vitamin E and vitamin C. Can J Phys 1993;71(9):725-731.

6. Pasquali M, Still MJ, Evinger JD, et al. Effect of vitamin C on pyridinum cross-link formation in skin fibroblasts from patients with Ehlers-Danlos syndrome type VI. J Invest Med 1996;44(3):226A.

7. Chandra RK. Nutrition and the immune system: An introduction. Am J Clin Nutr 1997;66:460S-3S.

8. Kelley DS and Bendich A. Essential nutrients and immunologic functions. Am J Clin Nutr 1996;63(6):994S-6S.

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11. Miller MJ. Injuries to athletes. Med Times 1960;88(3):313-316.

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13. Bucca C, Rolla G, Oliva A, et al. Effect of vitamin C on histamine bronchial responsiveness of patients with allergic rhinitis. Ann Allergy 1990;65:311-314.

14. Zuskin E, Lewis AJ, Bouhuys A. Inhibition of histamine-induced airways constriction by ascorbic acid. J Allergy Clin Immunol 1973;51:213.

15. Riskin SL. High dose vitamin C in allergy. Am J Dig Dis 1945;12:281.

16. Holmes HN. Hay fever and vitamin C. Science 1942;96:497.

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19. Kritchevsky SB, Shimakawa T, Tell GS, et al. Dietary antioxidants and carotid artery wall thickness. Circulation 1995;92:2142-2150.

20. Jacques PF. Effects of vitamin C on high-density lipoprotein cholesterol and blood pressure. J Am Col Nutr 1992;11(2):139-144.

21. Gatto LM, Hallen GK, Brown AJ, et al. Ascorbic acid induces a favorable lipoprotein profile in women. J Am Col Nutr 1996;15(2):154-158.

22. Garland DL. Ascorbic acid and the eye. Am J Clin Nutr 1991;54:1198S-1202S.

23. Hankinson SE, Stampfer MJ, Seddon JM, et al. Nutrient intake and cataract extraction in women: A prospective study. BMJ 1992;305:335-339.

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25. Waring AJ, Drake IM, Schorah CJ, et al. Ascorbic acid and total vitamin C concentrations in plasma, gastric juice, and gastrointestinal mucosa: Effects of gastritis and oral supplementation. Gut 1996;38:171-176.

26. Liyanage C, Goonaratna C, and Thabrew I. Iron absorption from a traditional Sri Lankan weaning food and the enhancing effect of ascorbic acid in adult make volunteers. Ceylon Med J 1996;41(4):135-40.

27. Garrison R and Somer E. The Nutrition Desk Reference. Keats Publishing: New Canaan, CT, 1995, pp. 133-140.

28. Enstrom JE, Kanim LE, Klein MA, et al. Vitamin C intake and mortality among a sample of the United States population. Epidem 1992;3:194-202.

29. Leibovitz BE. Polyphenols & Bioflavonoids. Townsend Let Doc April 1994:310-316.

30. Vinson JA and Bose P. Comparative bioavailability to humans of ascorbic acid alone or in citrus extract. Am J Clin Nutr 1988;48:601-4.

31. Pauling, L. Vitamin C and the Common Cold. WH Freeman and Co 1970, chapter 4, pp 27.

32. Garrison R and Somer E. The Nutrition Desk Reference. Keats Publishing: New Canaan, CT, 1995, pp. 133-140.

33. Bland J. Vitamin C: The Future is Now. Keats Publishing: New Canaan, CT, 1995.

34. Levine M, Conry-Cantilena C, Wang Y, et al. Vitamin C pharmacokinetics in healthy volunteers: Evidence for a recommended dietary allowance. Proc Natl Acad Sci USA 1996;93:3704-3709.

35. Garrison R and Somer E. The Nutrition Desk Reference. Keats Publishing: New Canaan, CT, 1995,pp. 133-140.

36. Bhagavan HN and Wolkoff BI. Correlation between the disintegration time and the bioavailability of vitamin C tablets. Pharm Research 1993;10(2):239-242.

37. Hathcock JN. Vitamins and minerals: Efficacy and safety. Am J Clin Nutr 1997;66:427-37.

38. Johnston CS and Luo B. Comparison of the absorption and excretion of three commercially available sources of vitamin C. J Am Diet Assoc 1994;94(7):779-781.

39. Meyers DG, Maloley PA, and Weeks D. Safety of antioxidant vitamins. Arch Intern Med 1996;156:925-935.

40. Diplock AT. Safety of antioxidant vitamins and beta-carotene. Am J Clin Nutr 1995;62:1510S-1516S.

41. Hathcock JN. Vitamins and minerals: Efficacy and safety. Am J Clin Nutr 1997;66:427-437.