Antioxidants from diet or supplements do not alter inflammatory markers in adults with cardiovascular disease risk. A pilot randomized controlled trial

Nutr Res. 2018 Feb:50:63-72. doi: 10.1016/j.nutres.2017.10.017. Epub 2017 Nov 2.

Abstract

Antioxidants have been reported to have anti-inflammatory effects, but there is a lack of research comparing food to supplement antioxidant sources. The aim of this study was to determine if increases in intake of foods naturally rich in antioxidants would lower blood levels of inflammatory markers more than consuming antioxidant supplements among adults with cardiovascular disease risk factors. Eighty-eight generally healthy adults with ≥1 elevated risk factor for cardiovascular disease were randomized in a single-blind (diets)/double-blind (supplements), parallel-group study for 8 weeks. Participants consumed (1) usual diet and placebo pills (n = 29), (2) usual diet and antioxidant supplements (n = 29), or (3) antioxidant-rich foods closely matched to antioxidant content of supplements and placebo (n = 30). Usual diet combined with antioxidant supplements or increased antioxidant-rich food intake was designed to approximately double daily habitual antioxidant intake. Antioxidant pills included carotenoids, mixed tocopherols, vitamin C, and selenium. Fasting blood samples were analyzed for inflammatory marker concentrations of interleukin-6, monocyte chemotactic protein-1, and soluble intercellular adhesion molecule-1. Participants in the intervention groups successfully doubled most antioxidants as verified by diet records and elevated blood concentrations in treatment groups. Baseline levels of inflammatory markers for the entire study group were 110 ± 65 pg/mL for monocyte chemotactic protein-1, 0.9 ± 0.7 pg/mL for interleukin-6, and 217 ± 56 ng/mL for soluble intercellular adhesion molecule-1 (means ± standard deviation) and did not differ by treatment arm. After 8 weeks, there were no significant within-group changes or between-group 8-week change differences in inflammatory marker concentrations. In conclusion, no beneficial effects were detected on the inflammatory markers investigated in response to antioxidants from foods or supplements.

Keywords: Adults; Antioxidants; Diet; Inflammatory markers; Supplements.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-Inflammatory Agents / pharmacology
  • Anti-Inflammatory Agents / therapeutic use
  • Antioxidants / pharmacology*
  • Antioxidants / therapeutic use
  • Ascorbic Acid / pharmacology
  • Ascorbic Acid / therapeutic use
  • Biomarkers / blood
  • Cardiovascular Diseases / blood
  • Cardiovascular Diseases / etiology
  • Carotenoids / pharmacology*
  • Carotenoids / therapeutic use
  • Chemokine CCL2 / blood
  • Diet*
  • Dietary Supplements*
  • Double-Blind Method
  • Female
  • Humans
  • Inflammation / blood*
  • Inflammation / drug therapy
  • Intercellular Adhesion Molecule-1 / blood
  • Interleukin-6 / blood
  • Male
  • Middle Aged
  • Pilot Projects
  • Selenium / pharmacology*
  • Selenium / therapeutic use
  • Single-Blind Method
  • Tocopherols / pharmacology
  • Tocopherols / therapeutic use
  • Vitamins / pharmacology*
  • Vitamins / therapeutic use

Substances

  • Anti-Inflammatory Agents
  • Antioxidants
  • Biomarkers
  • Chemokine CCL2
  • Interleukin-6
  • Vitamins
  • Intercellular Adhesion Molecule-1
  • Carotenoids
  • Selenium
  • Ascorbic Acid
  • Tocopherols