Popular Diets & Heart Health: Which Ones Are Best? The American Heart Association Weighs In

Why do you follow a diet? Maybe you’re looking to lose some weight. Or you just prefer not to eat certain foods.

But for lots of folks, diets are critical for their health. What you eat matters. Watching what you eat is especially important if you have a heart condition like atherosclerosis (a build-up of fat and cholesterol, called plaque, in your blood vessels) or other health problems.

“What you eat impacts not just heart disease, but all chronic diseases,” says Mary Lou Perry, RD, a registered dietitian at UVA Health. “Food is medicine; food can help.”

We spoke with Perry and Katherine Basbaum, RD, also a registered dietitian at UVA Health. Both help UVA Health patients with their nutrition plans to keep them healthy.

What Does a Heart-Healthy Diet Look Like?

Of course, not every diet is the same. When you have heart disease, it’s important to know if your diet is actually keeping you healthy. Otherwise, you could wind up having a serious health problem, like a heart attack.

“’What can I eat?’ is the question I get all the time as an RD,” says Perry. “Time and time again, the evidence shows that if these 4 components are part of the nutrition pattern, then the eating pattern is ‘healthy.’” A heart-healthy diet includes:

• A focus on veggies, fruits, and whole grains 
• Fish, nuts, and lean meat
• Limited red meat and processed meat
• Limited salty and sugary foods

Basbaum also notes that with a heart-healthy diet, the majority of the fats you eat should be plant-based, unsaturated fats, like olive and canola oils, nuts and nut butters, seeds, avocado, etc. “There’s evidence showing that these poly and mono-unsaturated fats can help lower the ‘bad’ LDL cholesterol that contributes to atherosclerosis,” she says.

What Diets Are Good for My Heart?

A new article by the American Heart Association (AHA) can help you decide if you're actually following a heart-healthy diet. Published in the journal Circulation, the article compares 10 popular diets based on how healthy they are for your heart.

They compared the diets using the AHA’s 2021 Dietary Guidance to Improve Cardiovascular Health. "The scoring of each of the dietary patterns used the AHA's evidence-based dietary guidance to promote cardiovascular health," says Perry.

Grouping Diets Together to Compare

For the article, the AHA looked at several popular diets. It then grouped similar ones together:

• Dietary Approaches to Stop Hypertension (DASH) diet: includes the Nordic and Baltic diets. These diets focus on eating lots of veggies, fruits, whole grains, beans, nuts, seeds, and low-fat dairy. You can also have lean meats, poultry, fish, and some oils. This diet does limit saturated fats, fatty meats, salty or sugary foods, refined grains, and alcohol.
• Mediterranean diet: similar to the DASH diet, it’s also focused on veggies, fruit, beans, etc. You can also have lean meats, fish, and extra virgin olive oil, and some red wine (in moderation!). This diet avoids sugary drinks and sweets, dairy, and fatty meat.
• Pescatarian: a mostly plant-based diet (vegetarian). It’s not fully vegetarian, but no meat other than fish is included.
• Ovo-lacto vegetarian: Vegetarian, but does allow dairy and eggs. No meat of any kind.
• Vegan: a strictly plant-based diet without any animal products (no dairy, eggs, butter, honey, etc.).
• Low-fat: includes diets like Volumetrics and the Therapeutic Lifestyle Change (TLC) diet. With this diet, fat must be less than 30% of your total calories.
• Very low-fat: includes diets like Ornish, Esselstyn, Pritikin, McDougal, and the Physicians Committee for Responsible Medicine (PCRM) diets. Fat is limited to less than 10% of total calories.
• Low-carbohydrate: includes diets like South Beach, Zone, and low glycemic-index diets. Carbohydrates, which usually come from grains, bread, and sugar, are limited to 30-40% of your total calories.
• Paleo: concentrates on meats, fish, veggies, nuts, and fruit. It avoids grains, beans, and dairy foods.
• Keto/very low carbohydrate: includes diets like Atkins. Carbohydrates are limited to less than 10% of daily calories.

The diets were scored from 1-100, with a higher score meaning it more closely follows the AHA's 2021 guidance (and therefore better for your heart). The AHA then ranked these diets into 4 tiers. They put the diets that most closely follow their diet recommendations in Tier 1.

How Does Your Diet Compare?

Tier 1 diets had scores of 85 or higher. The most heart-healthy diets were:

• DASH (score: 100)
• Pescatarian (92)
• Mediterranean (89)
• Ovo-lacto vegetarian (86)

Not surprisingly, the DASH diet came out on top with a score of 100. Because it’s specifically made to lower blood pressure and improve heart health, it most closely follows the AHA’s eating recommendations.

“The Mediterranean Diet is probably the #1 diet that I recommend to patients, whether they’re a heart patient or not,” says Basbaum. “Not only has the science backed up its benefits for decades, but it allows you to enjoy a variety of foods with minimal restrictions. That makes it much more sustainable than many of the other popular diets.”

Diets in Tier 2 were:

• Vegan (78)
• Low-fat (78)

Diets in Tier 2 still had high scores of 75-85. But, since veganism can be restrictive, some people might have a hard time following it long-term or getting enough vitamin B-12. And there were some concerns with the way low-fat diets deal with certain fats compared to the AHA’s recommendations.

Tier 3 diets do not follow the AHA recommendations very closely. Diets in this tier scored between 55-74. They included:

• Very low-fat (72)
• Low-carbohydrate (64)

Concerns with these diets included restrictions on certain foods that the AHA’s guidance recommend, like nuts, fruits, and some oils.

Tier 4 diets don't follow the AHA’s heart-healthy diet recommendations. These include:

• Paleo (score: 53)
• Keto (31)

These diets may be popular for losing weight, but because they’re so restrictive, they’re not very balanced. "There is no denying that this eating pattern can lead to significant weight loss," says Basbaum. "And for many, losing weight can offset the severity of other medical conditions."

But these diets do have risks for people with heart conditions. Because they're so rich in saturated fat and cholesterol but are low in fruits, vegetables, and whole grains, Basbaum has had patients who have hurt their hearts when following these diets.

"Overall, I felt the AHA’s ranking process was very well-done and particularly appreciated that some of the diets were 'dinged' for over-restriction," says Basbaum. "Long-term adherence to dietary patterns with multiple restrictions is often too challenging."

Choosing a Heart-Healthy Diet For You

The AHA's rankings mainly highlight how important a balanced diet is for your heart.

All of these diets may have their benefits. But you should research and understand the upsides and downsides of any diet before committing to one.

Following the diets as outlined is also very important. “The AHA emphasizes that the high rankings bestowed on their top tier diets are based on the diets being implemented as intended,” says Basbaum. She means that people need to understand what different food groups contain. For example, don't assume that all breads fit the same diet. When you eat carbs, you want complex, high-fiber carbohydrates instead of refined, sugary starches, she notes.

It’s always best to talk with your healthcare provider before settling on a long-term nutrition plan. A registered dietician, for instance, is an expert in nutrition and how it affects health, reminds Perry. They can guide you to a heart-healthy diet plan that helps you follow your health goals. Otherwise, while you may be seeing benefits in some areas, you may hurt yourself in ways you don’t realize.