August M
If you’ve been obsessing over cutting carbs or slashing fat to protect your heart, scientists say you may be asking the wrong question.New research suggests the real answer isn’t about choosing sides — it’s about choosing better food.
According to NBC News, a massive long-term study of nearly 200,000 adults found that both low-fat and low-carb diets can lower the risk of coronary heart disease — but only if they focus on high-quality, plant-based foods and whole grains.
The real heart hero
Coronary heart disease happens when plaque builds up in the arteries, restricting oxygen-rich blood flow to the heart. It can lead to chest pain, heart attack or sudden cardiac arrest.
Researchers tracked participants for more than 30 years. Over that period, 20,033 people developed confirmed coronary heart disease.
Those who most strictly followed a healthy low-carb diet saw a 15% lower risk of heart disease. People who closely stuck to a healthy low-fat diet had a 13% lower risk.
“It’s the quality of your diet that matters,” said lead author Dr. Qi Sun of the Harvard T.H. Chan School of Public Health.
What “healthy” really means
Healthy versions of both diets emphasized whole grains, vegetables, fruits (not juice), nuts, legumes and plant-based fats. The difference between low-fat and low-carb came down to proportions — not food quality.
On the flip side, so-called low-carb diets packed with fatty meats and butter — or low-fat diets loaded with refined grains and processed foods — were linked to higher heart disease risk.
People with the most unhealthy low-carb diets had a 14% increased risk of heart disease. The unhealthiest low-fat eaters had a 12% increased risk.
Specifically, those who closely followed an animal-based low-carb diet had a 7% higher risk of developing coronary heart disease.
Blood doesn’t lie
To strengthen the findings, researchers didn’t rely only on food questionnaires. They also analyzed blood samples from more than 11,000 participants.
Healthier eaters showed better metabolite profiles — biological markers linked to lower heart disease risk. As Sun put it, these measures “cannot lie.”
Dr. Dariush Mozaffarian of Tufts University told NBC News the study reinforces a message scientists have been repeating for years: it’s not fat versus carbs — it’s real food versus processed food.
Experts added that combining a high-quality diet with exercise, no smoking and good blood pressure control could cut heart disease risk by as much as 75% to 80%.
The bottom line
If you’re choosing between low-fat and low-carb, the science says either can protect your heart — as long as your plate is filled with whole, nutrient-dense foods.
It’s not about ditching carbs or fearing fat. It’s about ditching junk.
Sources: NBC News, Journal of the American College of Cardiology
