Heart disease kills more Americans than any other cause—roughly 695,000 deaths a year, according to the Centers for Disease Control and Prevention. That's about one in every five deaths. And while genetics, age, and family history are out of your control, the single most powerful lever you can pull is the one sitting on your dinner plate.

"I tell patients that food is the most powerful drug we have, and it's one they take three times a day," says Dr. Kim Williams, a cardiologist and former president of the American College of Cardiology. "No statin comes close to what a good diet can do across an entire population."

So what does a good diet actually look like? Not the one with the loudest marketing. Cardiologists tend to converge on a handful of eating patterns backed by decades of clinical trials and real-world data. Here's what they recommend, what they avoid, and why the difference matters for your arteries.

What Cardiologists Actually Eat—and Recommend

Ask a room full of cardiologists to name the best diet for heart health and you'll hear the same few names repeated: Mediterranean, DASH, and a whole-food, plant-forward approach that borrows from both.

The Mediterranean diet has the deepest evidence base. The landmark PREDIMED trial, published in the New England Journal of Medicine, followed nearly 7,500 people at high cardiovascular risk for about five years. Those assigned to a Mediterranean diet supplemented with olive oil or nuts had roughly a 30 percent lower risk of major cardiovascular events—heart attack, stroke, or death from cardiovascular causes—compared with a control group told to eat a low-fat diet.

The DASH diet (Dietary Approaches to Stop Hypertension) was designed specifically to lower blood pressure. In controlled feeding studies, it dropped systolic blood pressure by 8 to 14 points in people with hypertension—comparable to a single blood pressure medication. The National Heart, Lung, and Blood Institute funds and promotes it for exactly that reason.

Both diets share the same backbone: vegetables, fruits, whole grains, legumes, nuts, fish, and olive oil. They limit red meat, processed meat, refined grains, added sugar, and sodium. The differences are mostly cultural and culinary—DASH emphasizes low-fat dairy and tighter sodium limits, while Mediterranean allows more olive oil and fish.

"The best diet for your heart is one you can actually stick to for the next thirty years," Williams says. "Perfection for six weeks beats nothing. Consistency for decades beats everything."

Why These Diets Work: The Biology in Plain English

Cardiologists don't recommend these diets because they sound virtuous. They recommend them because the mechanisms are well understood.

They lower LDL cholesterol. Soluble fiber from oats, beans, and barley binds cholesterol in the gut and pulls it out of the body. Replacing saturated fat with unsaturated fat—olive oil instead of butter, nuts instead of cheese—directly lowers LDL, the "bad" cholesterol that builds plaque in artery walls. A 2021 study in the journal Circulation found that replacing just 5 percent of calories from saturated fat with polyunsaturated fat cut heart disease risk by about 25 percent.

They reduce inflammation. Chronic low-grade inflammation is a driver of atherosclerosis, the hardening and narrowing of arteries. Diets rich in fatty fish, nuts, fruits, and vegetables lower markers like C-reactive protein. The Mediterranean diet consistently shows some of the strongest anti-inflammatory effects of any eating pattern studied.

They improve blood pressure. Potassium, magnesium, calcium, and fiber all help relax blood vessel walls. Cutting sodium helps too. The average American eats about 3,400 milligrams of sodium a day—well above the 2,300-milligram federal guideline and more than double the 1,500 milligrams the American Heart Association recommends for people with high blood pressure.

They feed the gut microbiome. Fiber ferments in the colon and produces short-chain fatty acids that reduce inflammation and support healthy blood vessel function. Americans eat about 15 grams of fiber a day on average. The recommended target is 25 to 38 grams. That gap matters for your heart.

Diets That Fall Short for Heart Health

Not every popular diet earns a cardiologist's endorsement. Some are neutral. A few are actively harmful.

Keto and carnivore diets. These plans push fat to 70 to 80 percent of calories and slash carbohydrates to near zero. Short-term weight loss can be dramatic, and some markers like triglycerides improve. But LDL cholesterol often rises sharply in a subset of people—sometimes called "lean mass hyper-responders"—and long-term cardiovascular data is concerning. A 2023 analysis presented at the American College of Cardiology found that people on low-carbohydrate, high-fat diets had significantly higher LDL cholesterol and roughly double the risk of major cardiac events over a decade compared with those eating a balanced diet.

Paleo. Better than keto in some respects because it emphasizes vegetables and lean meats. But it excludes legumes and whole grains—two of the most heart-protective food groups. That's a meaningful loss for no clear benefit.

Juice cleanses and detoxes. There's no evidence they improve heart health, and they can spike blood sugar while stripping out fiber. Cardiologists generally view them as expensive ways to feel virtuous for a week.

Standard low-fat diets from the 1990s. The old advice to cut all fat led many Americans to replace fat with refined carbohydrates and added sugar—a trade that worsened heart health rather than improving it. The type of fat matters far more than the total amount.

How to Start: Practical Steps That Work

You don't need to overhaul your kitchen overnight. Cardiologists say small, durable changes beat dramatic ones that collapse by February.

  • Swap, don't subtract. Replace butter with olive oil. Replace white rice with brown rice or quinoa. Replace deli meat with grilled chicken or canned salmon. You're adding heart-healthy foods, not just removing favorites.
  • Aim for five servings of vegetables and fruit a day. That's the threshold where most studies show measurable cardiovascular benefit. Frozen and canned (no-salt-added) count just as much as fresh.
  • Eat fish twice a week. Fatty fish like salmon, sardines, mackerel, and tuna deliver omega-3 fatty acids that lower triglycerides and reduce arrhythmia risk. If you don't eat fish, talk to your doctor about a supplement.
  • Cut sodium where it hides. About 70 percent of the sodium Americans eat comes from packaged and restaurant food, not the salt shaker. Read labels on bread, canned soup, frozen meals, and condiments.
  • Limit processed meat. The World Health Organization classifies bacon, hot dogs, and deli meat as Group 1 carcinogens, and they're also linked to higher heart disease risk. Treat them as occasional foods, not daily staples.
  • Drink water instead of sugary drinks. Regular soda and sweetened beverages are among the strongest dietary drivers of weight gain, type 2 diabetes, and heart disease in US adults.
  • Cook at home more often. Restaurant meals average far more calories, sodium, and saturated fat than home-cooked food. Even modest home cooking—four or five dinners a week—makes a measurable difference.

What About Supplements and "Heart-Healthy" Labels?

The supplement aisle is a graveyard of good intentions. Vitamin E, beta-carotene, and high-dose B vitamins have all failed in large randomized trials to prevent heart disease. Some, like beta-carotene in smokers, increased risk.

Two exceptions have modest evidence. Omega-3 supplements (particularly high-dose EPA) can lower triglycerides and may reduce cardiovascular events in people with existing disease. And a daily multivitamin showed a small but statistically significant reduction in cancer and, in one large trial, a hint of cardiovascular benefit—though cardiologists don't consider it a substitute for real food.

Food labels are another trap. "Heart-healthy" is not a regulated term. "Low-fat" often means high-sugar. "Made with whole grains" can mean a sprinkle of oats in a refined-flour product. The most reliable label-reading rule is simple: if the ingredient list is long and contains things you wouldn't find in a kitchen, treat it with suspicion.

The American Heart Association's dietary guidance is blunt about this: eat food, mostly plants, not too much. That's the whole game.