A systematic review of the association between cardiovascular risk factors and regular consumption of oats

Purpose - To review the evidence from high quality human intervention studies that reported links between oat consumption and cardiovascular disease (CVD) risk factors. Design/methodology/approach - Using Medline, a search was made for all randomized controlled trials published between 1990 and 2008 that met defined inclusion criteria. Studies had a minimum duration of 14 days, used oat products rather than purified extracts, and included plasma lipid levels as outcome variables. Findings - A total of 21 eligible studies were located 13 of which reported significant reductions in total cholesterol when oats were consumed, while 14 reported significant reductions in low-density lipoprotein cholesterol. A few studies found increases in high-density lipoprotein cholesterol and more favourable cholesterol ratios when oats were consumed. Research limitations/implications - It was not possible to analyse differences in response between health and at risk subjects. A meta-analysis would be a useful step forward, as would research on the long-term impact of oats on body weight. Practical implications - Intakes of oats in successful intervention studies were impractical for most consumers. However, expert bodies base approved health claims on an achievable 3 g beta-glucan per day. Additional research on portion sizes for commercially-available foods would increase consumer awareness of how to access the cholesterol-lowering benefits of oats. Effective portion sizes may differ by gender, age and CVD risk. Originality/value - This review provides further evidence that regular oat consumption is an effective dietary strategy for helping to attenuate CVD risk and sets this within the context of claims for food stuffs.