Looking for a healthy, inexpensive protein that can boost your immune system and help you live longer? Grab some legumes the next time you're at the grocery store.

According to a 2022 study published in the journal PLOS Medicine, swapping out red meats and processed foods for legumes, whole grains, vegetables can increase life expectancy by more than a decade for people in their 20s or 30s.

Legumes: The most underrated longevity food

Many people don't instantly think of legumes when it comes to longevity foods. But as a nutritionist, I eat them every day as part of my vegan diet to keep my body strong and help fight off sickness.

The most common varieties of legumes are beans, including black beans, lentil beans, soybeans, fava beans, garbanzo beans (chickpeas), kidney beans, edamame and lima beans.

Here are some key health benefits of legumes:

• Protein: Legumes are an excellent source of protein, which is essential for many biological functions. One cup provides five to 10 grams of protein.
• Fiber: Legumes are an important source of dietary fiber — one cup contains four to 14 grams. Fiber helps strengthen the immune system, lower cholesterol, reduce inflammation, manage blood sugar and weight, and enhance gastrointestinal health.
• Minerals: Legumes contain minerals like potassium, calcium, iron, magnesium and zinc. These play essential roles in processes like oxygen utilization and immune function.
• Antioxidants: Beans contain several polyphenol compounds (a.k.a. healthy plant chemicals), including tannins, phenolic acids and flavonoids. These are potent antioxidants that repair cells and tissue.

All of these nutritional characteristics can protect against chronic diseases, research shows.

In fact, the American Cancer Society, American Diabetes Association and the American Heart Association recommend eating legumes as an alternative to animal proteins to help lower the risk of cancer, type 2 diabetes and heart disease.

How to add more legumes into your diet

As a busy professional, I love that I can create a variety of delicious, nutrient-packed meals with legumes.

You can buy prepackaged dry legumes at most supermarkets and health food stores. It might seem like a lot of preparation is needed, but most of that time is just the soaking process, which requires no additional work on your part.

You can also cook legumes in large batches and store them in sealed containers in the fridge or freezer:

1. Thoroughly cook dried beans.
2. Rinse and soak them for at least five hours.
3. Drain the soaking water and cook the beans in fresh, boiling water (212 degrees Fahrenheit) for at least 10 minutes.
4. Do not cook dried beans in slow cookers or crockpots, as the temperature doesn't get high enough to deactivate the lectins, a potentially toxic chemical found in raw beans.

Canned beans are already cooked, so all you have to do is toss them into your soup, chili, pasta, sauce, burrito or vegetable sauté.

Easy recipes

1. Go meatless by swapping hamburgers for legume-based burgers.

When mixed up with spices and fun flavors, homemade bean and lentil burgers can be just as tasty as their meat counterparts. Whether you use black beans, white beans, or lentils, you can't go wrong with a legume patty on a whole wheat bun.

2. Substitute mayonnaise for creamy hummus.

With the help of a food processor or blender, homemade hummus is easier to whip up than you think, and it makes a healthier, more fiber-filled sandwich spread than mayonnaise.

3. Mash legumes to turn them into easy dips. 

Thanks to the neutral taste of legumes, spices can really elevate them into any kind of party dip you're looking to create. From cheesy to savory to sweet, the possibilities are endless.

4. Ditch the chips for bean crisps.

If you're stuck in an afternoon slump, crunchy, oven-roasted beans can make for a satisfying, energizing snack. Lupini beans, fava beans, and chickpeas all get crispy in the oven and are easy to make in big batches for portioning throughout the week.

5. Stir them into soups for added fiber.

Lentil soup is a hearty meal for lunch or dinner come winter. For some more variety, you can also try making other legume-based soups, such as split pea soup, pasta e fagioli, or white bean and escarole soup.

6. Hide beans in brownies.

If you've got a sweet tooth, black bean brownies are a delicious dessert that packs a punch of fiber into every serving.

Samantha Heller, MS, RD, CDN, is a registered dietitian and exercise physiologist. She is a senior clinical nutritionist at NYU Langone Health in New York City. Follow her on Twitter and Instagram and Facebook.

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