After reading the new review, some experts have raised concerns about the contents of the breakfasts that people were given in clinical trials.
“When you look at the intervention groups, what they were given for breakfast is not generally what we would recommend people eat,” Liz Weinandy, a registered dietitian at Ohio State University Wexner Medical Center, told Healthline.
For example, participants in several trials were given processed cereals, such as Kellogg’s Rice Krispies or Frosted Flakes. In one study, they were given white bread with strawberry jam. These foods are high in refined carbohydrates and low in fiber and protein.
“I could see where this would add weight gain, because if you have a really high-carbohydrate breakfast, especially without fiber or protein, that makes people hungry again sooner,” Weinandy said.
“It makes your blood sugar go up fast, and your body secretes a lot of insulin to pull it back down, and then people get hungry again more quickly,” she explained.
Sharon Zarabi, a registered dietitian and bariatric program director at Lenox Hill Hospital, agrees.
“It’s not the breakfast, it’s what we’re eating for breakfast,” Zarabi said.
Breakfasts rich in fiber, protein, and healthy fats can help people feel full for longer, compared to meals high in refined carbohydrates, she says.
That’s why it’s not enough to count calories, she adds.
Instead, Zarabi encourages people to pay attention to the macronutrient contents of their meals and choose foods rich in nutrients.