Scientists have found that eating fewer calories can translate into a longer life, but early evidence came from studies on yeast and other organisms or animals, like mice and monkeys. The Calerie clinical trial at Duke University in Durham, N.C., is the first controlled study of calorie restriction in healthy people. Drawing from that data, a study published in 2022 showed that eating 14 percent fewer calories for two years had a significant effect on the thymus, an immune-supporting gland that produces T cells that fight infections.

Adults 40 and older who ate breakfast and took in at least 25 grams of fiber per day had a 21 percent lower risk of dying over a 12-year period. That’s according to an analysis of national data from the West Virginia University School of Medicine published in 2021 in the Journal of the American Board of Family Medicine.

While getting fiber from a variety of plant foods is important, there may be an extra benefit from including fiber from grain foods (such as whole grains and whole-grain bread and cereals) in your day, says Rupak Shivakoti, PhD, an assistant professor of epidemiology at Columbia University’s Mailman School of Public Health in New York City. One study he and his colleagues did, published in JAMA Network Open, found that men and women 65 and older who ate more foods rich in grain fiber had lower levels of various markers of inflammation. Reducing inflammation may play a role in decreasing the risk of heart disease, the leading cause of death in the U.S., and other conditions.

And you might enjoy your morning cup of java even more when you hear that it may help you live longer. Coffee is rich in compounds called polyphenols, which can protect cells against damage. In a 2017 study published in Annals of Internal Medicine, almost 200,000 people—Black, Latino, white, native Hawaiian, and Japanese American ages 45 to 75 at the start of the study—were followed for an average of 16 years. Those who drank a cup of regular or decaf coffee per day had a 12 percent lower risk of dying from any cause during the study period. Just go easy on the cream and sugar.

The more produce a person eats, the lower the risk of death from any cause—up to five servings per day (three servings of veggies and two of fruit), according to a 2021 study published in the journal Circulation that tracked more than 100,000 men and women over 30 years. Eating more than five daily servings didn’t seem to offer substantially more benefits. And note that potatoes and fruit juices weren’t linked to the same benefits as other forms of produce. It’s best to eat a variety of fruits and vegetables instead of relying on the same types because doing so means you get an array of nutrients.

Too much saturated fat (found in red meat and butter) can lead to clogged arteries and raise the risk for heart disease. Even cutting small amounts can have a benefit. A study in the journal Circulation Research reviewed data from more than 500,000 people collected by the National Institutes of Health (NIH) for more than 16 years. It found that replacing just 5 percent of calories from saturated fat with foods rich in monounsaturated fat, like avocados, or linoleic acid, a type of polyunsaturated fat found in nuts, seeds, and vegetable oils, was linked with a 15 and 8 percent lower risk of death, respectively.

Replacing animal sources of protein with plant protein may also give you extra years. The Norwegian study found that increasing the consumption of beans and lentils—which are among the best plant-protein sources—to ½ to 1 cup per day contributed the greatest gain in life expectancy. And replacing 3 percent of calories from animal proteins with plant proteins was linked with a 10 percent lower risk of early death in a 2020 study from the NIH that tracked more than 400,000 adults for 16 years. The benefit was even greater when the protein replaced was eggs or red meat, specifically.

Compared with people who never ate fish, those who had about 14 ounces each week (three to four 4-ounce servings) had a 12 percent lower risk of death from any cause, according to a review study in the European Journal of Clinical Nu­tri­tion. Use the acronym SMASH as an easy shorthand when choosing fish that are high in health-boosting omega-3s and low in mercury: salmon, mackerel (Atlantic), anchovies, sardines, and herring. In addition to omega-3s, fish also supplies key nutrients such as selenium, vitamin D, and zinc.

How can you accomplish all this at once? It doesn’t have to be overwhelming. Little things can add up and feel more manageable to do. Here are some easy swaps that make a difference.

• Sauté vegetables in olive oil instead of butter.

• Get guacamole on a taco salad instead of cheese.

• Order salmon at a steakhouse instead of prime rib.

• Halve the amount of pasta you dish out but double up on the veggies.

• Trade a baked potato with sour cream for roasted cauliflower with tahini.

• Make your go-to crunchy snack nuts instead of chips or pretzels.

• Try cinnamon to add flavor to your coffee instead of sugar.

• Have an orange instead of orange juice.

• Put roasted, spiced chickpeas in salads instead of croutons.

• Try a black-bean burger in place of a beef burger.

• Have oatmeal with blueberries and walnuts for breakfast instead of a blueberry muffin.

Editor’s Note: A version of this article also appeared in the July 2022 issue of Consumer Reports On Health.