With all the fad diets currently being pushed on the market, it is hard to know what type is the best to help lower heart disease risk. While everyone knows that maintaining healthy body weight is one key to preventing cardiovascular disease, even experts don’t agree on the best way to achieve that goal.
Some physicians recommend eliminating carbohydrates and others emphasize reducing fats to lose weight, but few studies have actually investigated the effect of these specific macronutrients on cardiovascular health.
This new study is one of the first to examine the effects of three healthy diets that emphasize different macronutrients including carbohydrates, proteins, or unsaturated fats on a biomarker that directly reflects heart injury. Published online in the International Journal of Cardiology, researchers at Beth Israel Deaconess Medical Center (BIDMC) used highly specific tests and found that all three diets reduced heart damage and inflammation resulting in improved heart health.
“It’s possible that macronutrients matter less than simply eating healthy foods,” said study author Stephen Juraschek, MD, Ph.D. “Our findings support flexibility in food selection for people attempting to eat a healthier diet and should make it easier. With the average American eating fewer than two servings of fruit and vegetables a day, the typical American diet is quite different from any of these diets, which all included at least four to six servings of fruits and vegetables a day.”
For the study, the team of researchers analyzed stored blood samples from 150 participants from the Optimal MacroNutrient Intake Trial to Prevent Heart Disease (OmniHeart), a two-center inpatient feeding study conducted in Boston and Baltimore between April 2003 and June 2005. All participants had elevated blood pressure but were not taking medications to control hypertension or cholesterol. They were required to consume each of three diets, emphasizing carbohydrates, protein, or unsaturated fat for six weeks, with diet periods separated by a washout period.
The diets that the participants were required to follow included a carbohydrate-rich diet with sugars, grains, and starches accounting for more than half of the calories. The second diet was a protein-rich diet accounting for 10 percent of calories from carbohydrates replaced with protein. The unsaturated fat-rich diet had 10 percent of calories from carbs replaced by the healthy fats found in avocados, fish, and nuts. All three diets were low in unhealthy saturated fats, sodium, and cholesterol.
A Change in Macronutrients
After looking at the effect of each diet on biomarkers measured at the end of each dietary period, it was shown that all three reduced heart injury and inflammation. However, changing the macronutrients of the diet did not provide extra benefits. This shows that the effects of diet on heart injury are fast and cardiac injury can be reduced soon after adopting a healthy diet. It also shows that it is not the type of diet that matters for cardiac injury, but rather the overall healthfulness of the diet.
“There are multiple debates about dietary carbs and fat, but the message from our data is clear: eating a balanced diet rich in fruits and vegetables, lean meats, and high in fiber that is restricted in red meats, sugary beverages, and sweets, will not only improve cardiovascular risk factors, but also reduce direct injury to the heart,” said Juraschek. “Hopefully, these findings will resonate with adults as they shop in grocery stores and with health practitioners providing counsel in clinics throughout the country.”
This study shows a clear message about eating for heart health. Don’t get caught up in the type of diet, but rather focus on consuming healthy, nutritious foods that will help the body heal.