Journal Article

Effect of alpha-linolenic acid in combination with the flavonol quercetin on markers of cardiovascular disease risk in healthy, non-obese adults: A randomized, double-blinded placebo-controlled crossover trial

Langguth, Peter, Burak, Constanze, Alteheld, Birgit, Fimmers, Rolf, Wolffram, Siegfried, Zur, Berndt, Stehle, Peter, Egert, Sarah

2019

Overview

•Alpha-linolenic acid (ALA) on a daily basis improved lipid profiles in healthy, non-obese men and women.•No evidence of a synergistic effect of ALA plus quercetin on cardiovascular disease risk markers.•Regular intake of supranutritional doses of quercetin increased plasma quercetin. Alpha-linolenic acid (ALA) and quercetin are characteristic compounds in plant-based diets. Cardioprotective effects have been described for both substances, although a possible benefit of combining ALA and quercetin has not, to our knowledge, been evaluated yet. The aim of this study was to investigate the potential independent and additive effects of ALA and quercetin on blood pressure (BP) and lipid and glucose metabolism, as well as on biomarkers of inflammation, oxidative stress, and antioxidant status in healthy, non-obese men and women. Another aim was to examine whether chronic supplementation of supranutritional doses of quercetin would result in an accumulation of plasma quercetin concentration over time. In a double-blinded, placebo-controlled crossover trial, healthy volunteers were randomized to receive 3.6 g/d ALA plus 190 mg/d quercetin or placebo for 8 wk. Data from 67 individuals (34 men, 33 women, mean age: 24.6 y) were assessed. Plasma quercetin, tamarixetin, isorhamnetin, and kaempferol increased significantly from baseline to study end with ALA + quercetin but not with ALA + placebo. No significant effect on office systolic BP, mean 24 h ambulatory BP (ABP), or mean daytime ABP was seen in either study group. Both interventions significantly decreased total cholesterol, low-density lipoprotein cholesterol, non–high-density lipoprotein cholesterol, and apolipoprotein B to a similar extent. No effect on high-density lipoprotein cholesterol, apolipoprotein A1, glucose, uric acid, oxidized low-density lipoprotein, C-reactive protein, or lipid-adjusted retinol, α-tocopherol, or β-carotene was seen in either group. Although dietary supplements of 3.6 g/d ALA over an 8-wk period improved lipid profiles in healthy adults, antioxidative and oxidative status, inflammation, and BP remained unchanged. No evidence was seen for an additive or synergistic effect of ALA plus quercetin on markers of cardiovascular disease risk.

• Publisher: Elsevier Inc,Elsevier Limited
• Subject: additive effect / Adult / Adults / Alpha-linolenic acid / alpha-Linolenic Acid - administration & dosage / alpha-Linolenic Acid - pharmacology / alpha-tocopherol / Antioxidants / apolipoprotein A-I / Apolipoprotein B / beta-carotene / Biomarkers / Biomarkers - blood / Blood pressure / C-reactive protein / cardioprotective effect / Cardiovascular disease risk markers / Cardiovascular diseases / Cardiovascular Diseases - blood / Cardiovascular Diseases - diagnosis / Carotene / Cholesterol / Clinical trials / Cross-Over Studies / Density / Diet / Dietary Supplements / Disease control / Double-Blind Method / Family medical history / Fasting / Fatty acids / Female / females / Flavonoids / Gene expression / Glucose / Glucose metabolism / Health risks / high density lipoprotein cholesterol / Humans / Inflammation / Intervention / isorhamnetin / Kaempferol / Linolenic acid / lipid composition / Lipid metabolism / Lipids / low density lipoprotein cholesterol / Male / males / Margarine / Metabolism / nutrition risk assessment / Obesity / Oxidative stress / placebos / plant-based diet / Proteins / Quercetin / Quercetin - administration & dosage / Quercetin - pharmacology / Randomization / Risk Factors / Skin / synergism / Synergistic effect / Tocopherol / Uric acid / Vitamin A / Womens health / Young Adult / β-Carotene