Why you should eat more pulses to boost brain and heart health

New research shows that eating more legume vegetables can protect against dementia and even prevent heart attacks.

Pulses are low in fat, high in fibre and cheap to buy. Picture: Getty Images

If you want to live a longer and healthier life, then you need to pack in the pulses. A study presented this week at the American Society for Nutrition conference is the latest to demonstrate the benefits of a diet rich in beans, peas and lentils.

The study, by researchers at Tufts University in Massachusetts, found that eating habits in middle age play a bigger role than previously thought in preventing memory decline, with those who ate plenty of vegetables, whole grains and pulses having much sharper brains in later life than those who did not.

And last month, in a study published in the American Journal of Nutrition, Harvard researchers showed that reducing consumption of meat and dairy, and eating more legumes and pulses, led to lower rates of premature death from heart disease, cancer and other diseases.

The description “pulses” tends to be used as shorthand for the broader category of legume vegetables. All beans, peas and pulses fall into the legume family, but the main difference between pulses and other legumes is that pulses are dried.

Dr Linia Patel, a spokesperson for the British Dietetic Association, was the lead author on a paper published in February’s European Journal of Clinical Nutrition that showed that people who ate one 40g portion of dried pulses (about three tablespoons when cooked) a week decreased their risk of colon cancer by 21 per cent compared with those who ate none. “We should be aiming to eat them two to three times a week ideally,” Patel says, “but even once a week would produce big health benefits.” Here’s why.

Two portions of pulses a week cuts bowel cancer risk by a third

According to Cancer Research UK, there are about 16,800 bowel and colon cancer deaths in the UK every year. High-fibre diets are known to reduce the risk of this disease, and with 5g of fibre in every 100g of pulses they were found to have a powerful preventive effect in Patel’s study.

“Our research showed that people who consume two or more portions, at least 80g of dried pulses, a week have 32 per cent lower odds of experiencing colon cancer than those who do not consume legumes,” Patel says.

“We think that the fibre feeds the beneficial bacteria in your gut, but in addition to that, legumes and pulses also contain bioactive compounds known as phenolics that are thought to help reduce the formation of cancer cells.”

High-fibre diets reduce the risk of bowel and colon cancer. Picture: Getty Images

A diet rich in pulses can help prevent dementia

Sticking to a healthy diet – which includes vegetables, whole grains and pulses – plays a vital role in warding off dementia, according to the study from Tufts University, which used data from 3000 British adults whose health has been tracked for more than 75 years as part of a research project.

They completed food diets at different ages as well as regular cognitive tests measuring brain function and memory. The study found that a person’s diet at the age of 43 was the strongest predictor of dementia risk in later life.

“Dietary patterns that are high in whole or less processed plant-food groups including leafy green vegetables, beans, whole fruits and whole grains may be most protective,” said Dr Kelly Cara, the author of the study.

Haricot beans increase the good bacteria in your gut

In a study published recently in the Lancet’s eBioMedicine journal, nutritionists from the University of Texas MD Anderson Cancer Center looked at the effects of adding one daily serving of canned haricot beans to the diets of obese people at risk of colon disease.

For eight weeks, half of the participants in the trial added a serving of the beans to their diet, while a control group continued to eat their regular food. From stool and blood samples, the researchers observed that the bean-eating group had greatly increased “microbial diversity”, with a rise in levels of beneficial bacteria including bifidobacterium and eubacterium, considered a sign of good gut health.

Eating more pulses in your sixties could add years to your life

Changing your diet to include more pulses and legumes and less red and processed meat could dramatically enhance your lifespan, according to Norwegian researchers reporting in PLOS Medicine in 2022.

Lars Fadnes of the University of Bergen and his colleagues found that people in their twenties who adopt a plant-heavy diet could live ten years longer than those who don’t change from a typical western diet – and the biggest gains come from eating more pulses and legumes.

Even doing so in your sixties increased life expectancy by eight years for women and almost nine years for men.

“Don’t marry yourself to one legume or pulse,” Patel says. “Variety is what makes the greatest difference.”

Pinto beans can protect against diabetes

The coating of dark-coloured beans, such as black and pinto varieties, is particularly rich in phenolic plant compounds that have antioxidant and anti-inflammatory properties. Last year a study published in the journal Food Research International reported that eating more of these beans can help to reduce inflammation in the body that is linked to disease.

“These phenolic compounds have the capability of keeping oxidation and inflammation under control, which could help decrease the risk of chronic health issues such as cardiovascular disease, cancer and diabetes,” said Elvira de Mejia, a professor in the Department of Food Science and Human Nutrition at the University of Illinois Urbana-Champaign and the lead author of the paper.

De Mejia said pinto beans had the highest total content of phenolic compounds “and showed great potential for inhibiting enzymes that contribute to inflammation”.

Eat pulses four times a week to cut your risk of heart disease

“Research shows that eating legumes and pulses four times a week can cut your risk of coronary disease by 14 per cent compared to those who eat them less than once a week,” says Rhiannon Lambert, a registered nutritionist and the author of The Science of Plant-Based Nutrition.

In one study published in the Canadian Medical Association Journal doctors found that a daily portion of chickpeas or lentils could significantly reduce the bad LDL cholesterol levels linked to heart disease.

A single serving of pulses a day can help with weight loss

With their high fibre and protein content, pulses “keep us fuller for longer and that also helps with blood-sugar control,” Patel says.

A study in The American Journal of Clinical Nutrition reviewed 21 clinical trials involving 940 adult men and women, who lost an average of 0.34kg over six weeks just by adding a single serving of pulses to their daily diet, but without making a particular effort to reduce other foods.

The Times