If you’re looking to live a long, healthy life, you might want to start incorporating more fruits, vegetables, nuts, and whole grains into your diet.

New research suggests that adding plant-based food items to your regular diet could decrease your risk of dying from causes of premature death like heart disease.

The new research out of Harvard was presented at the American Heart Association’s Epidemiology and Prevention/Lifestyle and Cardiometabolic Health Scientific Sessions 2019 on March 6 in Houston, Texas.

The study was based on data from both women and men who participated in two major national health studies.

The researchers looked at information on 47,983 women with an average age of 64 who participated in the Nurses’ Health Study, as well as 25,737 men, of the same average age, who participated in the Health Professionals Follow-Up Study.

None of these people had a prior history of cancer or heart disease when they entered their studies, and the researchers assessed changes in these people’s diets over a 12-year period from 1998 to 2014, according to an American Heart Association press release.

The research team, led by Dr. Megu Y. Baden, a postdoctoral research fellow in the department of nutrition at the Harvard T.H. Chan School of Public Health, devised three separate scales to measure how much plant-based foods people incorporated into their day-to-day diets.

These were: overall plant-based diet, healthy plant-based diet, and unhealthy plant-based diet.

The unhealthiest option included items like fruit juices, refined grains, sweets, and potatoes.

What did they observe?

Those who showed the largest increase in an overall plant-based diet had an 8 percent lower chance of dying from all causes.

Those who had a “healthy” plant-based diet had a 10 percent lower risk of death from heart disease. This type of diet involved replacing one serving each day of refined grains with whole grains. The diet also added one serving each day of fruits and vegetables, and decreased sugary beverages by one serving each day.

On the flip side, people who relied on the unhealthiest diet had an 11 percent higher chance of death.

How plant-based diets improve health

Baden told Healthline that these results were in line with previous research that showed plant-heavy diets decreased risk for type 2 diabetes and heart disease.

However, this study takes it a step further by showing just how much these foods can increase your longevity.

“We think our results emphasize the importance to consider the quality of plant foods,” Baden said.

When considering exactly why these foods are good at keeping you away from death’s door, Baden added that whole grain, fruit, and vegetable-heavy diets are known to decrease inflammation and have “antioxidant effects” on people’s dietary fibers and polyphenols, the micronutrients our bodies get from some of these healthy foods.

“The synergy of all the nutrients, fiber, water content, anti-inflammatory properties, antioxidants, and quality of a whole-foods, plant-based diet is both known from longitudinal and observational studies — though they may not be able to fully ‘ID’ causation — and also from shorter-term prospective studies that follow patients who improve their diets and improve their overall health status,” said Dana Hunnes, PhD, MPH, RD, a senior dietitian at UCLA Medical Center, who was not affiliated with this research.

Hunnes told Healthline that when people assess “blue zones,” which are places where people tend to live the longest and suffer from the fewest maladies, studies have found that people primarily eat “a plant-based diet with whole grains, legumes, nuts, seeds, fruits, and vegetables, and other unrefined plant foods.”

Ali Webster, PhD, RD, associate director of Nutrition Communications at the International Food Information Council Foundation, told Healthline that plant-based diets have long been tied to lowering a person’s risk for chronic diseases.

“Changing a typical, standard American or ‘Western diet’ to consist of more of these foods and fewer refined foods and sugars will go far to decrease premature death and disability,” she added.

That being said, she stressed that the latest research points out that it isn’t just the quantity but the quality of those foods that does the most for your health.

“Several studies have shown that people who eat plant-based diets tend to have lower body weight and BMI, lower cholesterol, lower blood sugar, and less abdominal — or visceral — fat, all of which are factors that play into risk for obesity, heart disease, and type 2 diabetes,” Webster, who was not associated with this research, said. “Healthful, high-quality plant-based diets can increase the amount of fiber and nutrients that we eat, while at the same time, reduce the amount of saturated fat and overall calorie intake.”

However, Webster explained that sometimes the actual definition of “plant-based diet” is vague. Not every study that looks into this is necessarily defining this diet regimen the same way.

Exactly what should you put on your dinner plate?

Given this variability, exactly what are the best plant-based food items you should put on your dinner plate if you want to live a long life?

Webster’s colleague, Alyssa Pike, RD, manager of nutrition communications at the International Food Information Council Foundation, told Healthline that not all plant-based diets are necessarily filled just with “plant foods.”

“There’s an emphasis on them with room for variety based on your preferences, budget, and access. Examples of plant-based foods include fruits, vegetables, whole grains (like farro, bulgur, brown rice, barley, buckwheat, and oatmeal), legumes (like lentils, chickpeas, beans, peanuts, and peas), nuts (like almonds, walnuts, cashews, Brazil nuts), and seeds (like flax, chia, sesame, and sunflower, to name a few),” Pike said.

Hunnes added that whole fruits like oranges, apples, pineapples, cantaloupes, and grapes are some great options, in addition to whole vegetables like cauliflower, Brussels sprouts, zucchini, and squash.

“I always recommend to replace meat with plant-based proteins including legumes, edamame, tofu, chia seeds, et cetera, and I always recommend to replace soda or even fruit juice with whole fruits and vegetables and water,” Hunnes said. “Refined fruit juice is nearly as detrimental for health as sugared soda because it lacks fiber and is quickly digestible.”

But for some people, changing a diet is easier said than done.

If you come across studies like this and want to make healthy changes to what you eat, Pike suggested that you “start with what’s available to you” in order to “set helpful, realistic goals.”

“Improved nutrition looks a little different for each person, taking into consideration one’s schedule, budget, and taste preferences. What we eat is only one piece of the puzzle of health,” Pike said. “Try making meals with at least three food groups. If you can, aim for fiber, healthy fat, and protein at each eating occasion. This combination helps with satiety and ensures we’re eating a wide range of vitamins and minerals.”

She added that, if you have time, try to prep some basic meals at the start of each week. This could be hard-boiling some eggs or making a simple pasta or rice dish that you can bring to the office or eat when you get back home at night.

“Some people go as far as preparing meals for the entire week, and that’s great, but it can sometimes feel overwhelming, so it may be better to start small,” Pike said.

She stressed that “fresh, frozen, and canned” are all viable options for plant-based foods. It doesn’t have to come straight from the garden.

“We typically think fresh is the only way to eat produce, but frozen and canned have longer shelf lives, and can be just as healthy. If you’re new to incorporating fruits and vegetables into your diet, don’t try to buy the entire produce section on the first go,” Pike suggested. “Instead, choose a couple and see how you do with those.”

Hunnes echoed those thoughts, saying that she usually recommends people add items rather than just subtracting at first. If you like your morning omelet, for instance, you can try to make it healthier by adding a portion of chopped veggies to the dish. Why not also add a side of a whole fruit?

“By doing this, instead of eating a refined-white-flour bagel with high-saturated-fat cream cheese and orange juice, you have just added two to three servings of fruits and vegetables,” Hunnes said. “By also adding slow-cooked oatmeal, you are adding a whole grain to the meal.”

Outside of breakfast, she said you can try adding a side salad or steamed or roasted vegetables to your lunch.

If you like fast food, Hunnes added that there are many chain restaurants now that offer “bowls” that can include whole grains, vegetables, and vegetable proteins.

Instead of going for the burrito wrapped in a white-flour tortilla filled with white rice and saturated fats, an on-the-go vegetable bowl could fill you up in a healthier way.

Being healthy can continue into dinner, too.

“For dinner, similarly, adding whole grains and vegetables or even fruit to your salads can go far in plumping up the fruit and vegetable intake. Also, adding legumes, or beans and nuts to the meal will add really healthy fats, protein, and fiber,” she said. “Again, there are so many nutrients that interact and interplay in a synergistic way to make this much easier.”

She added, “I usually like to tell people to pile on the fruits, vegetables, whole grains, legumes, nuts, and seeds, and crowd out the meat and sugar.”

The bottom line

New research out of Harvard that was presented this month suggests that incorporating quality plant-based foods into your diet decreases your chance of dying from heart disease and other causes.

Researchers looked at data on 47,983 women and 25,737 men from different national studies, following their shifts in diet over a 12-year period.

People who had the healthiest plant-based diet showed a 10 percent lower chance of premature death from a cause like heart disease.

People with the unhealthiest diets had a 11 percent higher chance of death.

Nutrition experts say that the quality of what you eat is more important than quantity.

Focus on daily helpings of whole wheat, whole fruits and vegetables, and nuts. Avoid things like fruit juices, refined grains, sweets, and potatoes if you want to increase your chance of longevity.