Vitamin Supplement Stores Articles & Resources

tea, and cocoa). The functional and health claims made by distributors of PYC are numerous. Among the claims are that PYC helps the body resist inflammation; protects against blood vessel and skin damage; improves the general function of the brain; relieves the distresses of arthritis, diabetes, and stroke; acts as a powerful antioxidant; and works synergistically with vitamin C, protecting it from degradation. The two latter claims were explored in the present study. The objectives of this study were to determine whether PYC increases the concentration of vitamin C in plasma, whether it increases total antioxidant capacity of serum in the fasting state and/or in the postprandial state, and whether it increases urine total antioxidant capacity.

Twenty-seven subjects were recruited into the study from the population at California State University. Subjects were between the ages of 19 and 42 years. All subjects were in good health, nonsmokers, and reported that they had not taken any medications or nutritional supplements in the month prior to the study. At the time the study started, the researchers had no information regarding how potent an antioxidant this supplement was. how long the supplement would impact antioxidant status, how bioavailable it was, how long it would take before it cleared the body, and other such. Therefore, they used a nonrandomized intervention design employing deception to induce a baseline period. The study took place over 4 weeks and was divided into two 2-week periods. Subjects were asked to follow their usual diet and activity patterns for the first period of 14 days (days 1-14) and to consume placebo pills twice per day with the breakfast and the evening meals (baseline). For the second period of 14 days (days 15 to 28), subjects were asked to continue to follow their usual diet and activity patterns and to consume PYC twice per day with the breakfast and evening meals (100 mg at each meal or 200 mg per day--intervention; the dose used is near the high end of what is commonly recommended by distributors). Blood was collected at two time points in the study; day 15 after the baseline period and day 29 after the PYC phase. The subjects' diets were assessed using estimated food records.

There was a significant association between dietary intake of vitamin C and the concentration of vitamin C in plasma. There was no apparent increase in the total antioxidant capacity of serum two weeks after supplementing the diet with PYC. One hour after the ingestion of a load dose of placebo or 200 mg of PYC, the antioxidant capacity of serum increased by an average of 15% to 19%. The total serum antioxidant capacity increased only 3% more than the apparent meal-induced increase in total serum antioxidant capacity 1 hr after consuming 200 mg of PYC. This increase did not reach statistical significance. The present study failed to detect measurable increases in the fasting levels of plasma vitamin C in a group of healthy young men and women consuming 200 mg of PYC daily for two weeks along with their usual diet.

Most claims made by the distributors of dietary supplements have not been substantiated by well-controlled human research studies. Dietetic professionals can disseminate to clients and consumers accurate and scientifically verifiable information concerning the validity of claims for dietary supplements. This study found nothing to support distributors' claims. The researchers suggest that consumers eat fruits and vegetables rich in nutrient and non-nutrient antioxidants to improve their vitamin C and antioxidant status, rather than a dietary supplement with questionable health claims.

K Silliman, J Parry, L Kirk, R Prior: Pycnogenol does not impact the antioxidant or vitamin C status of healthy young adults. JADA 103:67-72 (January 2003) [Correspondence: Kathryn Silliman, PhD, RD, California State University, Department of Biological Sciences, Program in Nutrition and Food Sciences, Chico, CA 95929-0002].