A new study suggests that this easy meal swap can help slow weight gain

Eating fewer carbohydrates can reduce weight gain over time. But just cutting carbs isn't enough.

An analysis of data from nearly 125,000 healthy adults found that replacing refined carbohydrates – white bread, white rice or sugary cereals – with whole grain foods and reducing animal-based fats and proteins appeared to reduce the amount of weight people gained over the age of four. year period, according to a report released Wednesday at the JAMA Network Open.

“When it comes to a low-carbohydrate diet, quality is paramount,” said the study's senior author, Dr. Gui Sun, an associate professor in the Departments of Nutrition and Epidemiology at the Harvard TH Chan School of Public Health. “The things people should focus on are high-quality carbohydrates.”

What are high-quality carbohydrates?

• Whole grains such as oatmeal, whole grain pasta or bread.
• Fats from vegetable oils, although not tropical, are high in saturated fats such as coconut or palm.
• Plant proteins such as beans, nuts and soy.
• Fruits.
• Vegetables.

Sun said it's best to stay away from refined grains like white flour, red and processed meats, and saturated fats.

The best animal protein is fish, followed by chicken, he said.

New research adds to growing evidence that diets high in healthy carbohydrates and plant-based proteins and fats are associated with significantly slower long-term weight gain.

To look closely at the impact of nutritional choices, Sun and her colleagues turned to three databases: the Nurses' Health Study, which enrolled 121,700 female nurses aged 30 to 55; The Nurses' Health Study II followed 116,340 female nurses aged 25–42 years at baseline; and the Health Professionals Follow-up Study, which enrolled 51,529 male health professionals aged 40 to 75 years.

For their analysis, Sun and his team focused on 123,332 men and women without chronic health conditions.

The researchers did not look at low-carb diets like keto, Atkins, or Paleo.

In general, Americans eat a diet that is 50% to 60% carbohydrate, Sun said. A low-carb diet typically consists of 30% to 40% carbohydrates.

The researchers rated people's diets based on the quality of their diets and assigned them to categories based on those scores:

• Animal-based low-carbohydrate diet (ALCD).
• Vegetable-based low-carbohydrate diet (VLCD).
• A healthy low-carbohydrate diet (HLCD), which emphasizes plant-based proteins, healthy fats, and less refined carbohydrates.
• An unhealthy low-carbohydrate diet (ULCD), which emphasizes animal proteins, unhealthy fats, and refined carbohydrates, including processed breads and grains.

Two animal protein-based categories have been linked to faster long-term weight gain.

“Quality is key in low-carb diets,” says Dr. Sahar Takkooch, MD, an obesity specialist and assistant professor of medicine at Vanderbilt University Medical Center in Nashville. “Healthy choices are key to better weight management.”

Even healthy choices can be unhealthy, however, depending on how they are served. Popped corn is a good whole-grain choice as long as it's not mixed with butter, sugar and salt, Sun said.

The research has some limitations, however, Dakouch said.

Most of the participants were white women, so it is unknown whether the findings would hold for other groups. And dietary information and people's weights are based on self-reports, which can be flawed.

Still, research looks at one area – Specific foods A low-carb diet that helps slow long-term weight gain — something that hasn't been researched yet, said Samaneh Farsijani, a registered dietitian in the department of epidemiology at the University of Pittsburgh School of Public Health.

“It tells people that it's important to follow a low-carbohydrate diet, but it's also important which foods they choose,” Farsijani said. “What I really like about this study is the emphasis on a healthy low-carb diet.”