According to new research from the University of Pennsylvania, eating late at night could be worse for your health than you might think.
Compared to eating earlier in the day, prolonged delayed eating can increase weight, insulin, and cholesterol levels, and negatively affect fat metabolism, and hormonal markers implicated in heart disease, diabetes, and other health problems, according to researchers.
The findings offer the first experimental evidence on the metabolic consequences of consistent delayed eating compared to daytime eating.
“Eating later can promote a negative profile of weight, energy, and hormone markers—such as higher glucose and insulin, which are implicated in diabetes, and cholesterol and triglycerides, which are linked with cardiovascular problems and other health conditions,” says Namni Goel, a research associate professor and lead author of the ongoing study.
The team found that when study participants ate later, compared to the daytime eaters, weight increased. Respiratory quotient, i.e. the ratio of carbon dioxide produced by the body to oxygen consumed by the body that indicates which macronutrients are being metabolized, also rose during delayed eating, indicating later eating led to metabolizing fewer lipids and more carbs.
The researchers also found that a series of other measures reflecting negative metabolic profiles increased in those eating later, including insulin, fasting glucose, cholesterol, and triglyceride levels.
Conducting a 24-hour hormonal profile, they also found that during daytime eating, the hormone ghrelin, which stimulates appetite, peaked earlier in the daytime, while leptin, which keeps you satiated, peaked later, suggesting that the participants received cues to eat earlier, and eating earlier likely helped them to stay satiated longer. This suggests that eating earlier may help prevent overeating in the evening and at night. As sleep-wake cycles were constant, melatonin levels remained constant in both groups.
“While lifestyle change is never easy, these findings suggest that eating earlier in the day may be worth the effort to help prevent these detrimental chronic health effects,” says Kelly Allison, associate professor of psychology in psychiatry and director of the Center for Weight and Eating Disorders, and senior author of the study.
“We have an extensive knowledge of how overeating affects health and body weight, but now we have a better understanding of how our body processes foods at different times of day over a long period of time.”
Similar yet much shorter previous studies have suggested similar results, but this is the first long-term study looking at the timing of eating patterns that also controlled for sleep-wake cycles, exercise, macronutrient intake, etc. to pinpoint the effects of prolonged eating at different times of day.
The National Institutes of Health funded the work. Additional authors of the study are from Penn and Johns Hopkins University.
This article is an excerpt from “Eating Late May Wreak Havoc on Your Body,” by Greg Richter-Penn on Futurity.org, shared with permission.
Do you, or a loved one, eat late at night? If so, has it affected your/their weight or sleep? Please share in the comments!
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