We've heard time and time again about the importance of eating breakfast but a new study suggests cutting back on what you eat in the morning might help you eat less during the rest of your waking hours.
The results show that, the more calories people eat at breakfast, the higher their total daily calorie intake is. This finding was true of both obese and normal weight people.
Participants ate around 500 to 550 calories for lunch and dinner, regardless of how much they ate for breakfast — it didn't matter whether they skipped it entirely or had a hearty morning meal, the researchers said.
As a result, those who ate a big breakfast — on average, 400 calories more than a small breakfast — took in 400 extra calories during their day.
"Overweight and obese subjects should consider the reduction of breakfast calories as a simple option to improve their daily energy balance," the researchers said.
"While we often hear that breakfast is the most important meal of the day, this study reminds us that monitoring calories at breakfast is very important, too," said Mary Ann Johnson, a professor of foods and nutrition at the University of Georgia and spokesperson for the American Society for Nutrition, who was not involved in the study. "The calories at breakfast do count toward overall daily intake."
However, other experts said this study isn't enough to rule out the importance of breakfast, and more work is needed to determine whether reducing your morning calories actually leads to weight loss.
Katherine Tallmadge, a spokeswoman for the American Dietetic Association, said that in her experience, "It's easier for people to eat healthy if they eat better breakfast."
Many overweight and obese people who are trying to lose weight eat too much later in the day, Tallmadge said. Eating a breakfast that contains one-third to one-quarter of their daily calories helps them cut back on calories at subsequent meals, Tallmadge said, because they aren't so ravenous.
"Almost everyone says [eating breakfast] helps them eat lighter later. And not gorge on their meals later," she said.
The difference between the findings in this study and what Tallmadge has seen in her experience may be that the participants in the study weren't actively trying to lose weight. Perhaps those who are trying to lose weight are more mindful of what they eat, and so they are better able to counter their bigger breakfast with lighter meals later on, she said.
Previous studies looking at the relationship between calories eaten at breakfast and the calories eaten throughout the entire day have shown mixed results. Some studies suggested that eating a big breakfast does lead to eating less for the rest of the day. Others have found the more calories a person consumes at breakfast relative to all meals combined, the lower his or her overall daily energy intake is. And some have shown those who eat breakfast weigh less than those who don't eat the morning meal.
To clarify these seemingly contradictory results, study researcher Volker Schusdziarra, of the Else-Kröner-Fresenius Center of Nutritional Medicine in Munich, Germany, and colleagues analyzed the daily calorie intakes of nearly 400 people in two different ways: they measured what people ate in absolute terms, and the ratio of their breakfast calories to their total daily calories.
In absolute terms, people who ate more calories at breakfast had consumed higher calorie totals at the end of the day. Eating a bigger breakfast did mean subjects were less likely to eat a mid-morning snack, but skipping the snack wasn't enough to compensate for their large morning meal, the researchers said.
Interestingly, people who had a higher ratio of breakfast calories to total daily calories had a lower intake of daily calories overall. But the researchers found this was because subjects were eating less at lunch and dinner, not because their breakfast intake had increased.
The study was published Jan. 17 in Nutrition Journal.
Pass it on: One study suggests eating less at breakfast may be a way to reduce your daily calories. But it's too soon to rule out the importance of breakfast, nutritionists say.
Follow MyHealthNewsDaily staff writer Rachael Rettner on Twitter @Rachael_MHND.
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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.