Effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction: a systematic review and meta-analysis of randomized controlled trials

Background:

Evidence from controlled trials encourages the intake of dietary pulses (beans, chickpeas, lentils and peas) as a method of improving dyslipidemia, but heart health guidelines have stopped short of ascribing specific benefits to this type of intervention or have graded the beneficial evidence as low. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction.

Methods:

We searched electronic databases and bibliographies of selected trials for relevant articles published through Feb. 5, 2014. We included RCTs of at least 3 weeks’ duration that compared a diet emphasizing dietary pulse intake with an isocaloric diet that did not include dietary pulses. The lipid targets investigated were low-density lipoprotein (LDL) cholesterol, apolipoprotein B and non–high-density lipoprotein (non-HDL) cholesterol. We pooled data using a random-effects model.

Results:

We identified 26 RCTs (n = 1037) that satisfied the inclusion criteria. Diets emphasizing dietary pulse intake at a median dose of 130 g/d (about 1 serving daily) significantly lowered LDL cholesterol levels compared with the control diets (mean difference −0.17 mmol/L, 95% confidence interval −0.25 to −0.09 mmol/L). Treatment effects on apolipoprotein B and non-HDL cholesterol were not observed.

Interpretation:

Our findings suggest that dietary pulse intake significantly reduces LDL cholesterol levels. Trials of longer duration and higher quality are needed to verify these results. Trial registration: ClinicalTrials.gov, no. {"type":"clinical-trial","attrs":{"text":"NCT01594567","term_id":"NCT01594567"}}NCT01594567.Abnormal blood concentrations of lipids are one of the most important modifiable risk factors for cardiovascular disease. Although statins are effective in reducing low-density lipoprotein (LDL) cholesterol levels, major health organizations have maintained that the initial and essential approach to the prevention and management of cardiovascular disease is to modify dietary and lifestyle patterns.^1–4Dietary non–oil-seed pulses (beans, chickpeas, lentils and peas) are foods that have received particular attention for their ability to reduce the risk of cardiovascular disease. Consumption of dietary pulses was associated with a reduction in cardiovascular disease in a large observational study⁵ and with improvements in LDL cholesterol levels in small trials.^6–8 Although most guidelines on the prevention of major chronic diseases encourage the consumption of dietary pulses as part of a healthy strategy,^2,3,9–13 none has included recommendations based on the direct benefits of lowering lipid concentrations or reducing the risk of cardiovascular disease. In all cases, the evidence on which recommendations have been based was assigned a low grade,^2,3,9–13 and dyslipidemia guidelines do not address dietary pulse intake directly.^1,4To improve the evidence on which dietary guidelines are based, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) of the effect of dietary pulse intake on established therapeutic lipid targets for cardiovascular risk reduction. The lipid targets were LDL cholesterol, apolipoprotein B and non–high-density lipoprotein (non-HDL) cholesterol.