An increase in dietary n-3 fatty acids decreases a marker of bone resorption in humans

Nutr J. 2007 Jan 16:6:2. doi: 10.1186/1475-2891-6-2.

Abstract

Human, animal, and in vitro research indicates a beneficial effect of appropriate amounts of omega-3 (n-3) polyunsaturated fatty acids (PUFA) on bone health. This is the first controlled feeding study in humans to evaluate the effect of dietary plant-derived n-3 PUFA on bone turnover, assessed by serum concentrations of N-telopeptides (NTx) and bone-specific alkaline phosphatase (BSAP). Subjects (n = 23) consumed each diet for 6 weeks in a randomized, 3-period crossover design: 1) Average American Diet (AAD; [34% total fat, 13% saturated fatty acids (SFA), 13% monounsaturated fatty acids (MUFA), 9% PUFA (7.7% LA, 0.8% ALA)]), 2) Linoleic Acid Diet (LA; [37% total fat, 9% SFA, 12% MUFA, 16% PUFA (12.6% LA, 3.6% ALA)]), and 3) alpha-Linolenic Acid Diet (ALA; [38% total fat, 8% SFA, 12% MUFA, 17% PUFA (10.5% LA, 6.5% ALA)]). Walnuts and flaxseed oil were the predominant sources of ALA. NTx levels were significantly lower following the ALA diet (13.20 +/- 1.21 nM BCE), relative to the AAD (15.59 +/- 1.21 nM BCE) (p < 0.05). Mean NTx level following the LA diet was 13.80 +/- 1.21 nM BCE. There was no change in levels of BSAP across the three diets. Concentrations of NTx were positively correlated with the pro-inflammatory cytokine TNFalpha for all three diets. The results indicate that plant sources of dietary n-3 PUFA may have a protective effect on bone metabolism via a decrease in bone resorption in the presence of consistent levels of bone formation.

Publication types

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

MeSH terms

  • Alkaline Phosphatase / blood
  • Biomarkers / blood*
  • Body Mass Index
  • Bone Resorption / drug therapy*
  • Collagen Type I / blood
  • Cross-Over Studies
  • Dietary Fats, Unsaturated / administration & dosage*
  • Double-Blind Method
  • Fatty Acids / blood
  • Fatty Acids, Omega-3 / administration & dosage*
  • Female
  • Humans
  • Linoleic Acid / administration & dosage
  • Male
  • Middle Aged
  • Peptides / blood
  • Tumor Necrosis Factor-alpha / analysis
  • alpha-Linolenic Acid / administration & dosage

Substances

  • Biomarkers
  • Collagen Type I
  • Dietary Fats, Unsaturated
  • Fatty Acids
  • Fatty Acids, Omega-3
  • Peptides
  • Tumor Necrosis Factor-alpha
  • collagen type I trimeric cross-linked peptide
  • alpha-Linolenic Acid
  • Linoleic Acid
  • Alkaline Phosphatase