Effect of supplemental phytonutrients on impairment of the flow-mediated brachial artery vasoactivity after a single high-fat meal.
OBJECTIVE
Our objective was to determine if long-term daily administration of phytonutrient supplements can prevent the immediate adverse impact of a high-fat meal and increase the production of nitric oxide.


BACKGROUND
Ingestion of a high-fat meal impairs flow-mediated vasodilation of the brachial artery for at least 4 h; however, co-ingestion of vitamin antioxidants or a green salad has been shown to prevent this effect.


METHODS
Flow-mediated brachial artery reactivity test (BART) both before and 3 h after a 900 calorie 50 g fat meal was evaluated in 38 healthy volunteers (age 36.4 +/- 10.1 years). Subjects were randomized to four weeks of daily supplementation with a powdered fruit vegetable juice concentrate (Juice Plus [JP]) along with a complex supplement providing nutritional antioxidants and various herbal extracts (Vineyard [V]), JP alone, or a matching placebo. At three and four weeks, BART was repeated both before and after the high-fat meal. Serum nitrate/nitrite concentrations were measured at baseline and at four weeks.


RESULTS
Four weeks of the JP-V combination blunted the detrimental effect of the high-fat meal (-47.5 +/- 23.4% at baseline vs. -1.7 +/- 9.7% at four weeks [p < 0.05]). Four weeks of JP alone had a similar beneficial effect (-45.1 +/- 19.7% at baseline vs. -16.6 +/- 10.3% at four weeks [p < 0.05]), whereas there was no substantial effect of the placebo. In the subjects treated with supplements, concentrations of serum nitrate/nitrite increased from 78 +/- 39 to 114 +/- 62 microm/l (p < 0.02).


CONCLUSIONS
Daily ingestion of modest amounts of a fruit/vegetable juice concentrate with or without adjunctive phytonutrient supplementation can reduce the immediate adverse impact of high-fat meals on flow-mediated vasoactivity and increase nitrate/nitrite blood concentration.
Plotnick
Gary D
GD
Cardiology Division, University of Maryland School of Medicine, Medical Center, 22 South Greene Street, Baltimore, MD 21201, USA. gplotnic@medicine.umaryland.edu
Corretti
Mary C
MC
Vogel
Robert A
RA
Hesslink
Robert
R
Wise
John A
JA
D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology*; D001916:Brachial Artery / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000517:prevention & control; D002784:Cholesterol / Q000097:blood; D004041:Dietary Fats / Q000009:adverse effects*; D019587:Dietary Supplements; D004311:Double-Blind Method; D004730:Endothelium, Vascular / Q000502:physiology; D005260:Female; D005638:Fruit; D006710:Homocysteine / Q000097:blood; D006801:Humans; D008297:Male; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000494:pharmacology; D009573:Nitrites / Q000097:blood; D028321:Plant Preparations / Q000494:pharmacology*; D014280:Triglycerides / Q000097:blood; D014664:Vasodilation; D014675:Vegetables; D014815:Vitamins / Q000008:administration & dosage / Q000494:pharmacology*
D000975:Antioxidants; D004041:Dietary Fats; D009566:Nitrates; D009573:Nitrites; D028321:Plant Preparations; D014280:Triglycerides; D014815:Vitamins; D006710:Homocysteine; D009569:Nitric Oxide; D002784:Cholesterol