If you still needed an extra reason to get that five a day, you should know that researchers just released a study concluding that legume consumption is associated with a lower risk of diabetes.
Legumes such as beans, chickpea, or lentil, are a significant source of protein, dietary fiber, carbohydrates and dietary minerals. They contain no cholesterol and little fat or sodium. In case you don't know what this means, it means that legumes are really good for you. Researchers write:
"Legumes, a low-energy, nutrient-dense and low glycemic index food, have shown beneficial effects on glycemic control and adiposity. As such, legumes are widely recommended in diabetic diets, even though there is little evidence that their consumption protects against type 2 diabetes."
They analyzed 3349 participants at high risk of cardiovascular disease but without type 2 diabetes. After four years, individuals who ate more legumes (28.75 grams/day, equivalent to 3,35 servings/week) had a 35% lower risk of developing type 2 diabetes. Lentil was especially highlighted, with people who consumed less than half a serving per week being 33% more likely to develop type 2 diabetes than those who ate up to a full portion a week.
Of course, correlation doesn't imply causation. As the paper itself states, it's very difficult to establish a cause-effect relationship between legumes and diabetes, but the idea that legumes fight diabetes is being supported by more and more evidence. This is not a new idea -- this idea has been embedded in popular belief for a long time, but surprisingly little scientific evidence has confirmed it so far.
Even something as small as replacing half a serving/day of foods rich in protein or carbohydrates (eggs, bread, potatoes with lentils, chickpeas, dry beans and fresh peas) can have a major effect. Especially in the context of a Mediterranean diet (characterized especially by a high consumption of vegetables and olive oil and moderate consumption of protein), legumes make a big difference. Researchers conclude:
"A frequent consumption of legumes, particularly lentils, in the context of a Mediterranean diet, may provide benefits on type 2 diabetes prevention in older adults at high cardiovascular risk."
Because they are a low-glycemic index food containing sizeable amounts of fibre and rich in B vitamins, legumes are a healthy source of nutrients and energy for humans. In fact, the Food and Agriculture Organization of the United Nations (FAO) declared 2016 as the international year of legumes to raise people's awareness of their nutritional benefits. While this study is a bit late to that part, it's still an important finding which shows just how important legumes are. The fact that a healthy diet protects against chronic diseases should surprise no one, but I'm happy when a study like this comes along and just underlines that fact even more.
Journal Reference: Reference: Becerra-Tomás N, Díaz-López A, Rosique-Esteban N, Ros E, Buil-Cosiales P, Corella D, Estruch R, Fitó M, Serra-Majem Ll, Arós F, Lamuela-Raventós R.M, Fiol M, Santos-Lozano J.M, Diez-Espino J, Portoles O, Salas-Salvadó J, PREDIMED study investigators. "Legume consumption is inversely associated with type 2 diabetes incidence in adults: a prospective assessment from the PREDIMED study". Clinical Nutrition (2017). http://dx.