If you’re looking for a sustainable nutrition plan—something that’ll suit you 20 years from now—you should stop looking at high-protein diets.

They’re popular now for dropping pounds quickly but they’re simply not practical beyond the horizon, said Harland Holman, MD, medical director at the Spectrum Health Family Medicine Residency Center.

“You can pick the high-protein diet to lose weight, but what you want to think about is the long-term,” Dr. Holman said. “If you go back to normal dieting, you’d put all that weight right back on. I’d recommend picking a diet you can stick with that’s healthy.”

America is deluged with new diets from year to year—high-fat, low-carb, high-protein—but in the end it seems the basics are best: a plant-based diet with fruits and vegetables, whole grains, legumes, nuts, and lean meats and seafood.

One diet in particular fits the bill: The Mediterranean.

“You’ll lose weight on it and you can also look at all the positive effects, even much later,” Dr. Holman said.

Ample evidence supports the benefits of a Mediterranean-style diet, including reduced risk of coronary heart disease, stroke and diabetes. Research also suggests that diet plays an outsized role in brain health, while a Mediterranean diet supplemented with olive or nuts is associated with improved cognitive function in older adults.

Calling it a Mediterranean “diet,” in fact, may be something of a misnomer.

“It’s not a diet—it’s not something you go on and quit,” said dietitian Jessica Corwin, a community nutrition educator at Spectrum Health Healthier Communities. “It’s a way of thinking about meals differently.”

Remember the old Clinton-era food pyramid, early 1990s or so? That majestic work of art featured bread, rice, cereal and pasta prominently at the bottom, recommending a carbtastic 6 to 11 servings per day.

Some illustrations of the Mediterranean food pyramid, meanwhile, don’t even show food at the bottom. They feature families playing and people interacting.

Seriously.

“The very base of the pyramid is about having fun, living an active lifestyle, and enjoying your food,” Corwin said. “It’s a stark contrast to our culture’s habit of racing through a meal while standing, driving or watching TV.”

As for actual food, the diet places heavy emphasis on leafy greens, vegetables, fruit and whole grains, building out from there.

Said Corwin: “Those following a plant-based Mediterranean Diet plan their meals around the vegetables, rather than the meat. Instead of saying, ‘OK, Monday we’ll have beef with something else,’ the focus switches to, ‘We have a ton of leafy greens we need to use up tonight, so what should we do with that?’”

First add nuts, beans, legumes, seeds, herbs, spices and olive oil, then fish and seafood. Poultry, eggs, cheese and yogurt would come once every other day, or perhaps a few times per week, with red meat and desserts just once or twice a month.

But the takeaway is not simply that the health benefits of a Mediterranean diet outpace any high-protein diets.

High-protein diets can increase your health risks. Research has shown that people who regularly consume high-protein foods—red meat, in particular—are effectively increasing their lifetime risk of chronic disease.

“Red meat, animal protein, has been linked to increased cardiovascular disease, cancer and diabetes,” Dr. Holman said.

A person with kidney problems, meanwhile, may see their condition worsen on a high-protein diet.

“When you have tons of protein, it’s harder for the kidneys to process and clear it,” Dr. Holman said. “Super-high protein levels can affect your kidneys. Most of the time, healthy people are OK, but if you’re predisposed to problems with your kidneys it can cause you to retain fluid.”

A predictable side effect of the diet craze: People are protein-crazy.

“Sometimes people don’t think they’re getting enough protein, but they are,” Dr. Holman said. “Most people overestimate how much protein they need.”

Smart dieting is the first step to positive lifestyle change, but don’t feel pressured to make dramatic changes immediately. Dr. Holman said he’ll first ask his patients to maintain a 24-hour food journal, carefully documenting the foods they typically eat in one day.

“You have to think about lifestyle change,” he said. “They’ll pick one or two things they can change. Sometimes it’s just as simple as cutting out soda. And most people don’t realize how healthy nuts are—they should switch to nuts as one of their snacks.”

The payoffs are real: Studies have shown people who adhere to a Mediterranean diet are about 30 percent less likely to develop cardiovascular disease, Dr. Holman said.