Eating a Late Dinner Can Drive Weight Gain

By Karen Eisenbraun, CHNC

September 16, 2020

Conventional nutritional wisdom tells us that managing weight is simply a matter of caloric intake. To lose weight, you need to burn more calories than you consume. 

This "calories in, calories out" theory of weight management is actually an extreme oversimplification that fails to consider the many factors influencing how our bodies actually use those calories. Factors such as chronic inflammation, hormonal imbalances, and certain genetic variants all affect how your body uses and stores energy. 

Another factor may be the timing of your meals. Research shows that eating dinner late at night can drive weight gain, regardless of the number of calories consumed. 

Eating Late Promotes Obesity

study published earlier this year found that eating a late dinner can increase blood sugar more than usual and impede the body's ability to burn fat. The study builds on previously existing research showing a relationship between obesity and eating late at night. Researchers wanted to conduct a randomized trial of healthy people to better determine how late meals impacted their metabolism. 

The study theorizes that eating out of sync with your body's natural circadian rhythms can interfere with proper metabolism. In the study, one group of participants ate dinner at 6 p.m. Another group ate the same meal at 10 p.m. Both groups went to bed at the same time, around 11 p.m. 

The study found that those who ate a late dinner had higher blood sugar levels and burned less fat than those who ate dinner at 6 p.m. The blood sugar of late eaters peaked at almost 20 percent higher than early eaters, and the ability to burn fat was reduced by 10 percent. They also had higher levels of cortisol, a hormone associated with stress that can cause weight gain. 

However, not everyone was impacted by a late dinner in the same way. People who were accustomed to going to bed earlier seemed to be most severely impacted by a late dinner. People who were already used to staying up late seem to be unaffected by eating a late dinner. These results suggest that eating too close to your usual bedtime may be the real issue, regardless of the actual time. 

Findings May Help With Disease Prevention

Although the study was conducted with young adults who were at a healthy weight, researchers believe the findings may have a significant bearing on healthy eating guidelines for disease prevention as well as weight management. The study serves as a reminder that certain eating habits impact not just weight, but also overall health and the risk of chronic disease.  

Chronically elevated blood sugar can lead to diabetes, and high levels of cortisol are associated with risk factors for heart disease. For individuals who are already at risk of these and other chronic health issues, being more mindful of meal timing may help reduce their risk.

How to Avoid Eating Too Late

People who are busy may find it difficult to stick to a consistent meal schedule. Eating a late lunch can often lead to a late dinner, as well as to overeating. For many people, being in quarantine due to COVID-19 has resulted in an even less regimented schedule, which can lead to irregular meal timing and mindless snacking throughout the day. 

Try to stick to a consistent schedule as much as possible. Even if you're working from home, try to get up and go to bed at the same time every day. If you know you'll be working late, keep high-protein snacks on hand to help curb hunger and avoid overeating later. Greek yogurt, a hard-boiled egg, or a handful of nuts are all good options for keeping hunger at bay. Then, if you do end up eating a later dinner, make it a smaller meal. 

You may also want to try making lunch your biggest meal of the day, rather than dinner. For many people, dinner is the largest meal of the day, and eating a large meal late at night places a greater burden on your digestive system. Aim for a small, lighter dinner, such as a salad with grilled chicken. 

Managing stress is also important for keeping cortisol levels under control. If you're experiencing high levels of stress and anxiety due to the COVID-19 pandemic, take steps to protect your mental health and see a therapist if necessary. 

Karen Eisenbraun is a Certified Holistic Nutrition Consultant. She holds an English degree from Knox College and has written extensively about topics related to holistic health, clinical nutrition, and weight management.

References: 

https://academic.oup.com/jcem/article-abstract/105/8/2789/5855227 

https://www.urmc.rochester.edu/encyclopedia/content.aspx

https://news.wellrx.com/2020/08/17/how-burnout-can-hurt-your-heart-and-cause-weight-gain/

https://news.wellrx.com/2020/03/30/how-to-watch-your-weight-during-a-quarantine/

https://news.wellrx.com/2020/05/27/stressed-and-tired-due-to-coronavirus-how-to-protect-your-mental-health/