Lean-seafood intake reduces cardiovascular lipid risk factors in healthy subjects: results from a randomized controlled trial with a crossover design

Am J Clin Nutr. 2015 Sep;102(3):582-92. doi: 10.3945/ajcn.115.112086. Epub 2015 Jul 29.


Background: Observational studies have strongly indicated an association between fish consumption and reduced risk of cardiovascular disease, but data from randomized controlled trials have been inconclusive.

Objective: Our primary outcome in this study was to elucidate the potentials of the 2 main dietary protein sources lean seafood and nonseafood to modulate fasting and postprandial lipids in healthy subjects. We hypothesized that lean-seafood intake would reduce cardiovascular lipid risk factors in healthy subjects more than would the intake of nonseafood protein sources.

Design: This study was a randomized controlled trial with a crossover design. After 3-wk run-in periods and separated by a 5-wk washout period, 20 healthy subjects (7 men and 13 women) consumed 2 balanced diets that varied in main protein sources (60% of total dietary proteins from lean-seafood or nonseafood sources for 4 wk). At days 1 and 28 of each intervention, fasting and postprandial blood samples were collected before and after consumption, respectively, of test meals with cod or lean beef.

Results: Relative to the nonseafood intervention, the lean-seafood intervention reduced fasting (relative difference by diets: 0.31 mmol/L; P = 0.03) and postprandial (P = 0.01) serum triacylglycerol concentrations. The lower serum triacylglycerol concentration was associated with reduced fasting triacylglycerol in chylomicrons and very-low-density lipoproteins (VLDLs) (P = 0.004), reduced fasting VLDL particle size (P = 0.04), and a reduced postprandial concentration of medium-sized VLDL particles (P = 0.02). The lean-seafood intervention prevented the elevated ratio of total cholesterol to HDL cholesterol in the fasted serum (P = 0.03) and postprandial serum (P = 0.01) that was observed after the nonseafood intervention.

Conclusion: The dietary protein source determines fasting and postprandial lipids in healthy individuals in a manner that may have an effect on the long-term development of cardiovascular disease. This study was registered at clinicaltrials.gov as NCT01708681.

Keywords: cardiovascular disease; dietary protein; lifestyle; lipoproteins; risk factors.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Mass Index
  • Cardiovascular Diseases / prevention & control*
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Chylomicrons / blood
  • Cross-Over Studies
  • Diet*
  • Dietary Carbohydrates / administration & dosage
  • Dietary Fats / administration & dosage
  • Dietary Proteins / administration & dosage
  • Energy Intake
  • Fasting
  • Fatty Acids, Monounsaturated / administration & dosage
  • Fatty Acids, Unsaturated / administration & dosage
  • Female
  • Healthy Volunteers
  • Humans
  • Lipoproteins, VLDL / blood
  • Male
  • Middle Aged
  • Postprandial Period
  • Risk Factors
  • Seafood*
  • Triglycerides / blood


  • Cholesterol, HDL
  • Cholesterol, LDL
  • Chylomicrons
  • Dietary Carbohydrates
  • Dietary Fats
  • Dietary Proteins
  • Fatty Acids, Monounsaturated
  • Fatty Acids, Unsaturated
  • Lipoproteins, VLDL
  • Triglycerides

Associated data

  • ClinicalTrials.gov/NCT01708681