Four week supplementation with mixed fruit and vegetable juice concentrates increased protective serum antioxidants and folate and decreased plasma homocysteine in Japanese subjects

Kawashima A, Madarame T, Koike H, Komatsu Y, Wise JA; Jan. 2007


Folate is known to reduce homocysteine, a recognized risk factor for heart disease and stroke. 


The aim of this clinical trial was to determine the bioavailability of antioxidants in an encapsulated fruit and vegetable juice powder concentrate (FV) and to gauge their effect on oxidative stress and DNA damage, folate status, and homocysteine in healthy younger adults, particularly smokers. 


Sixty men and women between the ages of 18 and 50 (average age 27.8 years), participated in this randomized, double-blind, placebo-controlled, parallel-group study. About half were smokers. The volunteers took either the fruit and vegetable juice powder concentrate (Juice Plus+®) 2 capsules each of the Fruit and Vegetable Blends daily with meals, half in the morning and half in the evening or placebo for 28 days. They were instructed to maintain their normal dietary and exercise patterns for the duration of the trial. Blood and urine samples were collected at baseline, day 14, and day 28 for analysis.  


After 28 days, when compared to the placebo group, volunteers taking the fruit and vegetable juice powder concentrate had significantly increased blood levels of antioxidants, evidenced by a 5-fold increase in beta-carotene, an 80% increase in lycopene, and almost 40% increase in vitamin E (alpha-tocopherol). In addition, their folate levels increased 174%. Meanwhile, levels of homocysteine and markers of oxidative stress both declined. Urine concentrations of 8-hydroxy-2’-deoxyguanosine (8-OHdG), a measure of oxidative damage to DNA, decreased in both the active and placebo group. Results were similar in smokers and non-smokers. 


Supplements derived from dehydrated fruit and vegetable juices have proved to be effective in raising the plasma levels of most of the nutrients studied and may be beneficial in improving the nutritional status in those individuals who do not eat sufficient fruits and vegetables. It is noteworthy that active smokers with increased levels of oxidative stress, after a short period of supplementation, showed improvements in antioxidant status comparable to those seen in non-smokers.

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