Nearly a third fewer cases
Eating around 170g of beans, lentils or chickpeas every day could cut the risk of developing high blood pressure by almost a third, according to a new analysis published in the journal BMJ Nutrition Prevention and Health. The study, which pooled data from 12 existing studies involving more than 150,000 participants across North America, Asia and Europe, found that people who consumed the highest amounts of legumes had a 16 per cent lower risk of hypertension compared with those who ate the least. For soy-based foods such as tofu and edamame, the equivalent reduction was 19 per cent. When the researchers calculated the effect at specific daily intakes, the figures were starker: a 30 per cent risk reduction for legumes at 170g per day, and a 28–29 per cent reduction for soy at 60–80g per day.
How much to eat
The researchers, who included academics from King’s College London, defined a serving size for both legumes and soy. They said 100g of cooked beans, peas, chickpeas, lentils or soybeans is roughly equivalent to one cup or five to six tablespoons, or a palm-sized portion of tofu. The optimal daily amount identified in the analysis was approximately 170g for legumes and 60–80g for soy foods such as tofu, soy milk, edamame, tempeh and miso. These figures are well above current consumption levels in the UK and Europe, where average legume intake stands at only 8–15g per day – far below the 65–100g per day already recommended for cardiovascular health. The team argued that their findings “provide further evidence in support of dietary recommendations to the public to prioritise and integrate legumes and soy foods as healthy protein sources in the diet”.
Why beans and soy work
The researchers pointed to several mechanisms that may explain the observed benefits. Both legumes and soy are rich in potassium and magnesium, minerals that have demonstrated blood-pressure-lowering effects. They also contain high levels of dietary fibre, which is consistently linked to lower rates of hypertension and overall cardiovascular disease risk. In addition, the briefing notes that fermented fibre from these foods may improve blood vessel function, and that soy contains bioactive compounds called isoflavones, which appear to support healthy blood pressure levels. The study authors said: “Several potential mechanisms and components within legumes and soy foods may explain or contribute to the observed benefits on hypertension risk, including their content of minerals, fibre and bioactive compounds.”
What the experts say
Tracy Parker, senior dietitian at the British Heart Foundation (BHF), said the study “adds to the growing evidence that legumes and soy foods can support healthier blood pressure as part of a whole‑food, plant‑based diet”. She noted that while the findings are observational and cannot prove cause and effect, “they reinforce existing UK guidance to eat more beans, lentils and other plant‑based foods”. Parker highlighted that legumes and soy are naturally low in saturated fat and salt, and provide fibre, potassium, magnesium and plant proteins – nutrients known to help maintain healthy blood pressure. She added that the amounts linked with lower risk “make them an affordable and easy choice to incorporate into everyday meals”, and suggested simple swaps such as choosing beans, lentils, chickpeas or tofu in place of processed meats.
Maeva May, director of research at the Stroke Association, emphasised that high blood pressure is the cause of around half of all strokes. “We’ve known for a long time that a Mediterranean diet, rich in soy and legumes, reduces the risk of stroke,” she said. “It protects heart and brain health by helping to prevent high blood pressure.” She urged people to combine dietary changes with regular exercise, not smoking or vaping, and moderate alcohol consumption. May also stressed the importance of regular blood pressure checks at a GP or pharmacy, noting that hypertension often has no symptoms yet affects about one in three adults in the UK. “Every day in the UK, 240 people are left with the life-changing consequences of stroke,” she added.
Previous research had already linked legumes and soy to a lower risk of heart disease, but evidence specifically on high blood pressure had been mixed. The new analysis, which synthesised data from a large and diverse group of participants, helps to clarify the picture. While the BHF cautioned that the findings are observational, they align with broader nutritional advice to prioritise plant-based proteins and increase fibre intake – for adults with hypertension, recommended daily fibre is more than 28g for women and more than 38g for men. The study also comes amid growing interest in personalised medicine: researchers at King’s College London have previously highlighted that ethnicity can influence how people respond to hypertension drugs, underscoring the need for tailored approaches. Diets rich in polyphenols – found in foods such as tea, coffee, berries, cocoa, nuts, whole grains and olive oil – have also been linked to healthier blood pressure and cholesterol profiles, adding to the case for a varied, plant-forward diet.
