How Changing the Timing of When You Eat Can Make You Healthier

New Year’s resolutions often revolve around healthier eating habits, but sticking to a specific diet or program can be tough—especially when you’re busy with work or rushing to pick the kids up from activities. Many people find it hard to eat healthy and balanced meals while on the road, or opt to skip lunch for a larger dinner out with friends.

But instead of entirely revamping your diet, what if you focused on the timing of your meals? More research is showing when you eat might help with disease prevention and weight loss. The concept is called "chrononutrition."

"It's all about the timing of eating," John Hawley, PhD, director of the Exercise and Nutrition Research Program at Australian Catholic University in Melbourne, told Verywell. "It's about the when, rather than the what."

What Is Chrononutrition?

In simple terms, chrononutrition, or time-restricted eating, looks at the impact nutrition has on your metabolism via your body’s circadian rhythm. Circadian rhythms—your body’s internal clock—govern the cycle of physiological and biological processes, like sleep, body temperature, and mental alertness. 

Eating on a schedule that better works with your natural rhythms benefits your wellbeing.

"It is thought that aligning your meals with your circadian rhythm may be associated with various health improvements, including reduced risk for chronic disease like diabetes and hypertension,” Lisa Young, PhD, RDN, an adjunct professor of nutrition at New York University, told Verywell. "This pattern of eating may also lead to improved sleep."

Hawley added that chrononutrition can also help with weight loss, as well as improve blood pressure and glycemic control.

Avoiding Late-Night Eating Is Key

Hawley said chrononutrition boils down to reducing the window of time that you eat. If you eat breakfast at 7:00 a.m., for example, and then eat dinner at 8 p.m., the goal is to shorten that timeframe of 13 hours down to 11 or 10 hours. 

This can be especially effective if you're living with certain health conditions.

"The warning bells for us when we’re dealing with obesity or type 2 diabetes are [people eating] within that 14, 15, 16-hour timeframe,” he said. “With time-restricted eating...we're trying to reduce that eating window."

Hawley emphasizes that's not the same thing as intermittent fasting. In fact, he says fasting “upsets” the notion of chrononutrition because periods of prolonged food restriction and chronic energy restriction ignore the body’s circadian rhythm. 

“There is an absence of meals [in intermittent fasting], whereas time-restricted eating is all about maintaining the normal circadian profile throughout the day," he said.

Avoiding late-night meals, in particular, is an important component of chrononutrition. According to Hawley, the body initiates a hormonal response any time you eat anything. If you eat during a time period when you're not expending much energy, you'll increase your hunger and appetite. What’s more, late-night eating is linked to impaired metabolic function.

"In the evening, blood glucose levels are high," Hawley said. "Because you're [likely] lying down and not doing anything, it stays elevated. By moving evening meals in earlier, time-restricted eating helps lower that nocturnal glucose profile."

Think of it as a chain reaction: Eating earlier can mean healthier blood sugar levels, which can mean a lower risk of diabetes and obesity.

Quality Food Still Matters

Even if you only eat during the day, it’s important you’re eating nourishing foods. In other words, what—and how much—you eat matters most, Young said.

“Eating junk food at regular intervals will still give you too much salt, sugar, saturated fats and too many calories, and will deprive your body of important vitamins and minerals,” she said.

How to Get Your Eating Schedule on Track

Sometimes you can't avoid a late-night meal, but constantly snacking before bedtime or skipping lunch to eat a massive dinner has impacts on your health. Luckily, both experts say getting back on track is pretty simple.

"The first step would be to get your sleep cycle in order and to keep it regular, since your eating [habits] often revolve around that,” Young said.

Then, try to set an ideal window for regular mealtimes—and shift breakfast to be later in the morning and dinner to be earlier, if possible.

"If you sleep from 11 p.m. to 7 a.m., aim for breakfast an hour or so after waking—sometime between 8 a.m. and 9 a.m.,” Young said.

If you have to eat later than usual, consider what you eat. Hawley said carbohydrate-rich and fatty foods are not ideal for late-night meals and opting for protein is better. 

As researchers conduct more studies on chrononutrition and the concept becomes mainstream, Hawley hopes more people will reap its rewards.

"In the next decade or so, we hope that there's enough solid evidence-based recommendations on time-restricted eating to include the timing in dietary recommendations,” he said. "It’s incredible that that’s currently lacking, but it is."