New Research Reveals Negative Health Effects of Late Night Eating

man reaching into the fridge late at night
From weight gain to heart disease, eating late could cause problems.

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Key Takeaways

  • New research suggests eating dinner later in the evening could cause weight gain, as well as increase risk for heart disease, stroke, and diabetes.
  • This can happen because meal timing may have negative effects on your metabolism.
  • Creating a consistent and early dinner schedule could provide benefits in other ways, such as helping you sleep better.

Eating dinner later in the evening could contribute to weight gain, and also set you up for potential health impacts like higher risk for heart disease, stroke, and diabetes, according to a new study in the Journal of Clinical Endocrinology & Metabolism.

Researchers studied 20 healthy volunteers to see how they metabolized meals eaten at 10 p.m. and 6 p.m. All participants went to bed at 11 p.m., and researchers found that blood sugar levels were higher with the later dinner, even when the same meal was eaten on a different day at the earlier time.

On average, the peak blood sugar level was about 18 percent higher, and the amount of fat burned overnight decreased by 10 percent compared to the earlier dinner. Chronically elevated blood sugar levels have been linked to cardiovascular issues and diabetes in previous studies since it can cause inflammation and affect vascular muscle cells.

Long-Term Strategy

Although the recent study and some previous research has highlighted the benefits of eating an earlier dinner, that doesn't mean you need to skip a meal if your schedule has you running into the evening, says dietitian Emily Tills, RDN, CDN of nutrition coaching firm Nourished with Emily.

For example, third-shift workers or those with hectic days may find a later dinner is the only time they have to sit and relax, and it's important to find enjoyment instead of stress in that meal, believes Tills. But if you're interested in losing weight or simply eating earlier to boost health benefits, creating a meal schedule that works better in the long-term is usually a matter of shifting gradually over time, Tills advises.

Emily Tills RDN, CDN

A few meals eaten later in the evening won't have a dramatic effect, it's more about what you do on a regular basis. Our bodies appreciate routine, so a better strategy is to begin to eat dinner earlier when you can until you can stick to that every night.

— Emily Tills RDN, CDN

This shift also involves thinking about your other meals as well, Tills adds. For instance, some people overeat at dinner because they've skipped lunch or waited too long after lunch to have dinner.

There's no exact timing for each meal, but a general rule is to have breakfast within an hour after waking up, then having lunch four to five hours later, and dinner four to five hours after that. Tills advises playing around with those timeframes to see what works best for you.

Focus on Consistency

Consistency in an eating schedule can bring numerous benefits, Tills adds, such as allowing you to plan your meals—a tactic the Centers for Disease Control has linked to making healthier food choices. It can also cut down on the kind of frequent grazing that can happen when meals are spaced too far apart. That level of snacking can cause an increase in calories while still leaving you feeling hungry.

Kristen Smith, RD

Another strategy that's helpful for creating consistency is to jot down when you eat and track the effect it has in other ways, like energy levels, sleep, and mood.

— Kristen Smith, RD

"Linking the timing of your meals to other benefits is often a good way to maintain a routine," she says. "It can keep you on track by letting you see that one beneficial habit influences another, and that's very motivating."

For example, you might notice you sleep poorly whenever you eat a few hours later than usual—which wouldn't be surprising, according to Hannah Dove, DPT, at Providence Saint John's Health Center in Santa Monica, Calif.

"Many people experience digestive issues when they eat late in the evening," she says. "Not only is the body trying to digest that food when it should be focusing on rest, but you may also experience problems like heartburn and acid reflux simply because of the position of your body. Lying down for hours with a full stomach is not ideal."

Mood, too, can take a hit when you space out meals too far apart. There's a reason "hangry" is now in the dictionary.

What This Means For You

Like any other strategy around food—especially if you're trying to lose weight—it's important to see tweaks like these as part of a long-term plan that's based on improving your health.

That perspective can guide you toward feeling a sense of self-care, rather than a way to create restrictive eating patterns or feel bad not just about what you eat, but also when you eat it.

Learn More

4 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Gu C, Brereton N, Schweitzer A, et al. Metabolic effects of late dinner in healthy volunteers - A randomized crossover clinical trial [published online ahead of print, 2020 Jun 11]J Clin Endocrinol Metab. 2020;dgaa354. doi:10.1210/clinem/dgaa354

  2. Reusch JE, Wang CC. Cardiovascular disease in diabetes: where does glucose fit in?J Clin Endocrinol Metab. 2011;96(8):2367-2376. doi:10.1210/jc.2010-3011

  3. CDC. Planning meals.

  4. Merriam-Webster. Hangry.

By Elizabeth Millard
Elizabeth Millard is a freelance journalist specializing in health, wellness, fitness, and nutrition.