Skip to content
ZenBodyLove

Legumes, whole grains, nuts

Randomised trials show that eating tree nuts or dietary pulses (beans, chickpeas, lentils, peas) lowers LDL cholesterol in adults, and large meta-analyses of cohort studies link higher whole grain and nut intake with lower cardiovascular disease and all-cause mortality. Cohort evidence for legumes and cardiovascular outcomes is weaker and graded low to very low by its authors. A modelling study that combines these meta-analyses estimates that eating more legumes, whole grains and nuts accounts for much of the predicted gain in life expectancy from a shift away from a typical Western diet, but its figures are population estimates under stated assumptions.

  • Longevity
  • Vegan

Evidence retrieved up to

What the research shows

In prospective cohort studies of adults, higher intake of dietary pulses and other legumes is associated with modestly lower incidence of cardiovascular disease, with weaker and less certain associations for coronary heart disease, hypertension and obesity, and no clear association with stroke or diabetes.

Low certaintyFurther research is likely to change this.
No known concerns at usual amountsBenefit

Who this is about

adults in the general population

Practical note

Graded low, matching the GRADE assessment by the review authors: 28 cohort studies, highest versus lowest intake, cardiovascular disease incidence risk ratio 0.92 graded low and all other outcomes very low.

Vegan note

Legumes are a staple protein source on a vegan diet.

Sources

A life-table modelling study combining meta-analyses with Global Burden of Disease data estimated that, among the dietary changes it modelled for adults moving away from a typical Western diet, eating more legumes, whole grains and nuts gave the largest predicted gains in population life expectancy.

Low certaintyFurther research is likely to change this.
No known concerns at usual amountsBenefit

Who this is about

adult populations eating a typical Western diet, modelled

Practical note

Graded low: a model resting on observational meta-analyses (the authors rated the input evidence moderate with NutriGrade) that yields population estimates under stated assumptions, not observed outcomes; downgraded for indirectness. The authors state the model is not meant as individualised forecasting.

Vegan note

Legumes, whole grains and nuts are all plant foods; the modelled optimal diet also included fish, which a vegan diet replaces with other plant foods.

Sources

In prospective cohort studies of adults, higher nut intake (tree nuts and peanuts alike) is associated with lower risk of cardiovascular disease and all-cause mortality, although nut eaters also differ in other lifestyle habits; as part of a healthy lifestyle, eating nuts may help reduce the risk of cardiovascular disease.

Low certaintyFurther research is likely to change this.
Take care: see the safety noteBenefit

Who this is about

adults in the general population

Practical note

Graded low: observational studies with moderate heterogeneity (I2 up to 66 percent for all-cause mortality) and confounding flagged by the 2015 AJCN authors. The 2016 BMC Medicine analysis reported risks per 28 g a day increase in nut intake.

Vegan note

Nuts are a plant source of protein, fat and minerals on a vegan diet.

Safety note

Tree nut and peanut allergies can cause severe reactions; people with a nut allergy avoid nuts entirely.

Sources

In randomised trials of adults, diets emphasising dietary pulses (beans, chickpeas, lentils and peas) lowered LDL cholesterol compared with similar-calorie diets without pulses.

Moderate certaintyFurther research may change the size of the effect.
No known concerns at usual amountsBenefit

Who this is about

adults

Practical note

Graded moderate: 26 RCTs with 1037 participants; downgraded one level for risk of bias and short trial duration, which the authors themselves flag. The trials used a median of 130 g of pulses a day (about one serving); no effect was seen on apolipoprotein B or non-HDL cholesterol.

Vegan note

Pulses are a staple protein source on a vegan diet.

Safety note

Some people notice more intestinal gas when they start eating beans; in three feeding studies fewer than half reported it in the first week, and the authors judged such concerns may be exaggerated.

Sources

In controlled trials of adults without cardiovascular disease, eating tree nuts lowered total cholesterol, LDL cholesterol, apolipoprotein B and triglycerides compared with control diets.

Moderate certaintyFurther research may change the size of the effect.
Take care: see the safety noteBenefit

Who this is about

adults without prevalent cardiovascular disease

Practical note

Graded moderate: 61 controlled trials with 2582 participants, little evidence of publication bias and no significant heterogeneity by nut type; downgraded one level because diet trials cannot be blinded and lasted only 3 to 26 weeks. Effects were standardised to one 28.4 g serving a day, with stronger effects in trials using 60 g a day or more.

Safety note

Tree nut allergies can cause severe reactions; people with a nut allergy avoid nuts entirely.

Sources

In prospective cohort studies of adults, higher whole grain intake is associated with lower risk of coronary heart disease, cardiovascular disease and all-cause mortality, while refined grains show little association; as part of a healthy lifestyle, eating whole grains may help reduce the risk of coronary heart disease and cardiovascular disease.

Moderate certaintyFurther research may change the size of the effect.
No known concerns at usual amountsBenefit

Who this is about

adults in the general population

Practical note

Graded moderate: observational evidence (45 studies in the 2016 BMJ meta-analysis) started at low and was upgraded for a consistent dose-response gradient with low heterogeneity for coronary heart disease; the 2019 Lancet review graded whole grain evidence low to moderate. The BMJ analysis reported risks per 90 g a day (about three servings), with reductions seen up to about 210-225 g a day.

Vegan note

Whole grains are plant foods and fit a vegan diet without change.

Safety note

Wheat, barley and rye contain gluten; people with coeliac disease rely on gluten-free whole grains such as brown rice, quinoa, buckwheat or oats certified gluten-free.

Sources