A Diet Low in 6 Key Foods Linked to Higher Risk of Heart Disease, Study Finds

A new study has just been published that further examines the relationship between diet and heart disease. Given that cardiovascular disease continues to be the leading cause of death in America, and this new information is welcomed with open arms by the healthcare community. 

With the data from this study, researchers were able to pinpoint six key food groups that, if lacking in the diet, are linked to increased heart disease risk—and one of which may surprise you. Here’s what the large-scale, long-term study found, including which foods are most important to eat regularly to reduce heart disease risk, and why each of these foods may be so impactful when it comes to heart health.

Nutrition Study Findings

For the study, published in July 2023 in European Heart Journal, the research group combined the results of six different studies: one epidemiological cohort study, three prospective studies, one randomized control trial, and two standardized case-control studies. The data collection spanned a significant amount of time, from 1999 to 2019, yielding 20 years of data from over 240,000 participants from 80 countries on six continents.

Participants came from all walks of life with varying income levels, lifestyles, and genetics. Researchers obtained information on their diet habits with food frequency questionnaires (FFQs), and they created a healthy diet score through meta analysis of this information.

This diet score rated the overall healthfulness of the participants’ diets and helped researchers identify six foods that, when consumed in high enough amounts, were associated with lower incidence of cardiac events. These events included diagnosis of heart disease, as well as occurrence of stroke, heart attack, heart failure, and total mortality.

The six food categories they found to be protective against these events were fruit, vegetables, legumes, nuts, fish, and full-fat dairy. From their data, the researchers were even able to determine the amounts that would yield the best heart health results:

• Fruit: Two to three one-cup servings daily
• Vegetables: Two to three one-cup servings daily
• Legumes: Three to four half-cup servings weekly
• Nuts: Seven one-ounce servings weekly
• Fish: Two to three three-ounce servings weekly
• Dairy: 14 servings weekly of either one cup of milk or yogurt, or 1.5 ounces of cheese

While most of these foods have been shown to be protective of heart health in the past through evidence-based eating strategies like the Dietary Approaches to Stop Hypertension (DASH) and the Mediterranean diet, the inclusion of full-fat dairy is somewhat uncharted territory (more on this in a second).

But what makes these six foods so special when it comes to heart health outcomes?

How These 6 Foods Benefit Heart Health

1. Fruits

When it comes to heart health, fruit offers such an important, not to mention impactful, array of nutrients. These include the full range of micronutrients including vitamins, minerals, and plant compounds. Plant compounds are especially beneficial to preserving heart health as they help to reduce systemic inflammation that, when unmanaged, can lead to cardiac illness. Plus, fruit is an excellent source of fiber. Fiber not only boosts gut and digestive health, but soluble fiber actually binds to dietary cholesterol in the small intestine helping to rid it from the body, as opposed to being absorbed into the bloodstream. Elevated cholesterol levels over long periods of time can contribute to atherosclerosis or plaque build-up on vein and artery walls that is so classically tied to heart disease.

2. Vegetables

Veggies offer much of the same heart health perks that fruits do: vitamins, minerals, plant compounds, and fiber. There are certain vitamins and minerals that many vegetables (and other plant-based foods) offer that are especially beneficial to heart health. These include the major electrolytes—phosphorus, sodium, magnesium, potassium, calcium, and chloride—as they help to maintain healthy heart rhythms. Plus, other micronutrients are linked to improvement in specific conditions that contribute to heart disease, like potassium and reduced blood pressure, for example.

3. Legumes

Not to sound like a broken record, but legumes also offer much of the same beneficial nutrients as fruits and veggies that champion heart health. However, what sets them apart is the protein they contain. While protein is an important source of energy for the body, it also continually helps to build and maintain healthy tissues, including muscles, organs, and blood cells (among many others). Through supporting the health of these vital structures in the body we can engage in everyday activities, like exercise, that are key to staying healthy and avoiding chronic illness like heart disease.

4. Nuts

Nuts (and seeds) really build on all of the above-highlighted nutrients: vitamins, minerals, plant compounds, fiber, and protein—and then they also bring healthy fats to the table. Nuts are an excellent source of heart-healthy, unsaturated fats that help to improve cholesterol levels, encourage healthy heart rhythm, and reduce heart-disease-contributing inflammation throughout the body.

5. Fish

Eating more fish and seafood has been such a common heart health recommendation in recent years as a great source of lean protein, vitamins, minerals, and heart-healthy fats. Fatty fish like salmon, tuna, mackerel, sardines, and anchovies (among others) are especially great sources of omega-3 fatty acids. These are supportive of heart health as anti-inflammatory agents in the body that help to lower triglyceride levels, maintain normal heart rhythms, and support the elasticity of blood vessels, therefore encouraging healthy blood pressure levels.

6. Full-Fat Dairy

More of the wild card on this list, perhaps, is the inclusion of full-fat dairy. Some dairy, especially full-fat varieties, has been previously thought of as a contributor to heart disease by many health professionals over the years. This is primarily due to the saturated fat and dietary cholesterol it contains. However, research is coming to find that there isn’t as strong of a correlation between these types of fat and heart disease as once thought. This could very well be part of the reason that this study found full-fat dairy to be linked with better heart health, when consumed in moderation. Fermented full-fat dairy products, like kefir, yogurt, certain cottage cheeses, and farmer’s cheese, have an even greater leg up when it comes to heart health benefits. The fermentation process involved in making these products converts some of the saturated fat in milk to heart-healthy, unsaturated fats. And research does show that, while subbing out saturated fats for carbohydrate-rich foods doesn’t decrease our heart disease risk, swapping out saturated fats for unsaturated fats does.

What Does This Mean for You?

So, what’s the bottom line here? Do you need to start eating these six key foods in the exact amounts the study found? Are you guaranteed to avoid heart disease if you follow the diet principles these researchers discovered?

In short, no. While this study does offer valuable new insights into dietary interventions that may keep heart disease at bay (mainly the inclusion of full-fat dairy), many of its findings are not all that ground-breaking. We’ve known for decades that including more plant-based foods and fatty fish into our meals results in better outcomes for heart health. That said, additional evidence is always welcome when it comes to educating, empowering, and motivating people to make heart-healthy nutritional choices.

Correlation vs. Causation

It’s important to note that this study is presenting observations and correlations, not cause and effect findings. This means that integrating these six heart-friendly foods into your healthy routine, even in the prescribed amounts, does not guarantee that you’ll never receive a heart disease diagnosis in your lifetime. What it does mean, however, is that variety and balance within the diet can make a huge difference when it comes to reducing your risk of developing chronic illness of any kind, including heart disease. And diet is only part of the picture – exercise and stress management are also key players to keep in mind.

Ultimately, this large study offers us yet another helpful reminder to prioritize variety and nutrient-dense foods in our everyday life to lower our risk of heart disease. And, it’s just a wonderful bonus that this way of eating also helps to prevent many other chronic diseases while leaving us feeling energized and capable in our day-to-day lives.