When it comes to losing weight and staying healthy, maybe we should pay more attention to the numbers on the clock than the numbers on the nutrition label.
A 2017 study published in the Journal of Nutrition found that people who ate their largest meal earlier in the day were more likely to have a lower body mass index (BMI) than people who consumed their biggest meal toward the end of the day.
Now, we've all heard the cliche that breakfast is the most important meal of the day. Most of us have probably heard how eating breakfast can help you lose weight. But this research is saying something different. It shows that consuming more of our calories at the start of the day and fewer at the end boosts metabolism, prevents obesity and reduces risk of heart disease by lowering blood pressure and cholesterol.
Skipping breakfast may not affect just your weight. It can also lead to other serious health complications.
A December 2018 review of several studies shows that skipping breakfast even just one day a week can increase a person's risk of developing Type 2 diabetes. Together the studies analyzed more than 96,000 people (5,000 of whom already had Type 2 diabetes) and found that those who didn't eat breakfast once a week had a 6 percent increase of having Type 2 diabetes. The more breakfasts a person missed, the higher the risk. For those who skipped four to five a week, the risk was 55 percent higher. The risks were also associated with higher BMIs, which is also noted in the 2017 study mentioned above.
The risks don't stop there.
Another 2017 study published in the Journal of the American College of Cardiology found that people who skip breakfast are more likely to have a condition called atherosclerosis, or hardening and narrowing of the arteries because of plaque, than people who have a hearty meal at the start of the day.
"A greater percentage of energy consumed earlier in the day may favor cardiovascular health," lead study author Dr. Valentín Fuster of the Spanish National Center for Cardiovascular Research in Madrid and Mount Sinai Heart in New York City told Reuters.
This is the opposite of how many of us eat, researchers say. We have a tendency to grab something small on the way to the office and sit down to a big dinner at night.
Though the Journal of Nutrition study was small — an observational study of 50,000 adults who are Seventh Day Adventists, a religious group that tends to have very healthy habits — it offered a peek into the weight-loss benefits of fasting, too. The lowest BMIs were found in the 8 percent of study participants who ate in the mornings and sometimes early afternoons before fasting for the next 18 hours.
As the New York Times reported in August 2017:
Fasting signals to the body to start burning stores of fat for fuel, the researchers said. “It seems our bodies are built to feast and fast,” said Dr. Hana Kahleova, one of the authors of the study, which was done by researchers at Loma Linda University School of Public Health in California. “It needs some regular cycling between having food intake and fasting. This seems to be hard-wired.”
This may explain why previous studies like this 2014 one, which countered the widely held belief that eating breakfast helped with weight loss, found that skipping breakfast had "no discernible effect on weight loss in free-living adults who were attempting to lose weight." Perhaps study participants were eating too late in the day; a person eating the same meal at different times of day might deposit more fat after an evening meal than a morning meal, Kahleova told the Times.
A growing body — of evidence
Medical research seems to be trending in this direction. In January, the American Heart Association issued a scientific statement in January 2017 on how meal planning can affect our heart health.
"Meal timing may affect health due to its impact on the body’s internal clock. In animal studies, it appears that when animals receive food while in an inactive phase, such as when they are sleeping, their internal clocks are reset in a way that can alter nutrient metabolism, resulting in greater weight gain, insulin resistance and inflammation," said Marie-Pierre St-Onge, Ph.D., an associate professor of nutritional medicine at Columbia University in New York City and one of the statement's authors.
So go ahead and sit down to a hearty breakfast. Those of us who eat breakfast each day are less likely to have high cholesterol and blood pressure, and people who skip a morning meal (which is 20 percent to 30 percent of U.S. adults) are more likely to be obese or diabetic, St-Onge said.
"We suggest eating mindfully, by paying attention to planning both what you eat and when you eat meals and snacks, to combat emotional eating. Many people find that emotions can trigger eating episodes when they are not hungry, which often leads to eating too many calories from foods that have low nutritional value," according to St-Onge.