As a cardiologist, one of the questions I’m asked most frequently is what the healthiest diet is for my heart. This is understandable, given that there is an abundance of misinformation out there. From the low-fat diet culture of the 90s to emerging fads like green juicing and keto, it’s hard to know whom to trust and what to eat.
A suboptimal diet is estimated to be responsible for an astonishing one in five deaths worldwide. However, you simply cannot out-run or out-meditate a lousy diet. The choices we make right now matter, and they dramatically impact our chance of developing heart disease in the future. So, let’s explore the science behind the food that can fuel our bodies to live longer, be healthier and feel better.
What do the scientific studies show we should eat?
Unfortunately, most Americans (and many worldwide) consume the aptly named Standard American Diet (SAD). This diet consists of highly processed foods, refined grains, fried foods, sugar-sweetened beverages and way too much meat (from animals that are often treated with hormones, antibiotics and fed unnatural foods). As a result, we are sicker than ever and feel awful.
We know from an overwhelming amount of evidence that eating more plants reduces our risk of heart attacks and stroke. Plants contain an abundance of fiber (vital for our gut health, blood sugar control and many more health-promoting actions) as well as vitamins, minerals, micronutrients, polyphenols and antioxidants. And eating more plants happens to be healthier for our planet (and the animals who live on it). Win-win!
Evidence suggests we should aim to eat a diet that is rich in quantity and variety of vegetables, fruits, whole grains, legumes (beans), nuts and seeds. Many trials have demonstrated lower rates of high blood pressure, cholesterol, obesity, inflammation and heart disease in those following a plant-predominant or plant-based diet.
While a wide variety of plants is recommended, a handful have emerged in the literature as particularly heart-healthy. I recommend ensuring green, leafy vegetables, antioxidant-rich berries, plant proteins (beans and soy-based products) and nuts play prominent roles in your diet when possible.
What should we try to cut down on or eliminate?
Hands down, processed red meat. Intake of processed meats (i.e., hamburgers, hotdogs and deli meats) has been consistently demonstrated to increase the risk of heart disease quite robustly. Unprocessed red meat, eggs and dairy show a similar but less profound association with heart disease. Importantly, replacing red meat with plant-based sources and NOT refined carbohydrates is associated with a lower risk of heart disease. Replacing plant protein for animal protein, particularly red meat, is associated with a reduction in death from any cause as well as death from cardiovascular disease.
Why might this be? Animal products tend to be high in saturated fat (which increases LDL cholesterol) and sodium. They also contain other bioactive molecules that appear to be detrimental to our health, including heme iron, nitrates and carnitine (which gets converted to TMAO, an active metabolite that has been linked to increased risk of cardiovascular disease).
Are all fats bad?
No. Despite the popularity of the “low-fat” diet of the 1990s, we have robust evidence that polyunsaturated and monounsaturated fats (mostly found in plant foods and fish) are heart-healthy compared to their counterparts, trans fats and saturated fats.
One study compared a low-fat diet to a Mediterranean diet supplemented with extra virgin olive oil or nuts. The group of individuals who consumed the plant-predominant Mediterranean diet high in monounsaturated and polyunsaturated fats reduced their cardiovascular events compared to the standard low-fat group.
In particular, omega-3’s (DHA, EPA and ALA) are an essential type of polyunsaturated fatty acids and appear important for heart health. They play an essential role in brain function, reducing inflammation and promoting normal growth and development. The studies regarding the benefit of supplementation are inconsistent (except in particular high-risk individuals), so obtaining adequate amounts of omega-3 fats in the diet is recommended. Long-chain fatty acids DHA and EPA can be found in fatty fish like salmon and sardines, and the short-chain fatty acid ALA can be found in many nuts and seeds (flax seeds, chia seeds, pumpkin seeds and walnuts).
What should we eat for better heart health?
First and foremost, my motto is “progress over perfection.” Things get crazy, and not every day will be full of Instagram-worthy meals. Do your best to set yourself up for success, and when it doesn’t happen, give yourself grace—and then keep on keeping on!
Start with one or two meatless meals a week. Unless you’re the rare type who likes to go all-in at once, I suggest starting slow. If you’ve already got one meatless meal down, I challenge you to add a second or third completely meat-free meal. Going slow can also help beat the bloat that can accompany a too-quick increase in fiber intake from eating more plants.
For the rest of your meals, focus on fitting in more plants rather than taking things away. Approach each meal as an opportunity to nourish your body by eating more colors and variety in terms of fruits, vegetables, whole grains, nuts and seeds. For some, shifting your mindset to focus on what you are adding rather than what you’re eliminating can be immensely helpful. If you have meat at a meal, limit that portion to ¼ of the plate and crowd it out with plants. Try to have the meat be the sideshow rather than the main attraction.
Eating a wide variety of plants is recommended. I encourage daily consumption of green, leafy vegetables, antioxidant-rich berries, plant proteins (beans and soy-based products), nuts (see next step) and seeds in particular. I love Nutrition Fact’s Daily Dozen app for those who are just beginning to keep track of their intake—#eattherainbow!
Extra virgin olive oil and nuts, high in heart-healthy monounsaturated and/or polyunsaturated fats, are good sources of plant-based fats. Both have emerged in medical trials to be cardioprotective when added to a plant-predominant diet. I typically use olive oil for dressings or when cooking at low to medium temperatures, and I tend to reach for avocado oil when cooking at high heat. Nuts and nut butters are great for snacks and meal accompaniments.
If you’re searching for additional inspiration, please check out my website for more tips on heart-healthy living. Lastly, if you’re still feeling stuck, a personalized dietary plan that takes into account dietary preferences and your unique risk factors can be crucial to your success—so, please see a registered dietitian or lifestyle-focused physician to help you on your journey toward better health.
If you missed it, Dr. Harkin's first post on the specific heart health issues that women need to be aware of, you can read it here.
Resources
Ramón Estruch et al. NEJM. Primary Prevention of Cardiovascular Disease with a Mediterranean Diet
Mingyang Song et al. JAMA. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality
Women's Health Initiative. Changing the Future of Women’s Health
Nicole Harkin, MD, FACC
Nicole Harkin, MD, FACC, is board-certified in Internal Medicine, Cardiology, Echocardiography, Nuclear Cardiology, and Clinical Lipidology. After graduating from Boston University School of Medicine, she attended Columbia University for her Internal Medicine residency and New York University for her Cardiology fellowship. She also served as a chief fellow and an assistant attending. She is a fellow of the American College of Cardiology and a member of the National Lipid Association and American Society for Preventive Cardiology.
Dr. Harkin helped countless patients treat and prevent their heart disease in her private cardiology practice in Manhattan. She recently moved to San Francisco with her family and founded Whole Heart Cardiology, a preventive telecardiology practice with the mission of providing patient-centered cardiac care, evidence-based nutritional guidance and personalized lifestyle plans for her patients in a modern setting. She takes pride in helping her patients achieve their goals, feel better and thrive.
When not doctoring, she spends the majority of her time with her three young children. She also enjoys cooking, yoga, Pelotoning, hiking and traveling.
Instagram: @nicoleharkinmd