If there was one thing to take away from the session “Meal Timing and Cardiometabolic Health: Implications for Mechanisms,” presented at SLEEP 2024, the 38th annual meeting of the Society of Sleep Professionals, it was that it’s best to eat meals earlier in the day.1
Many studies have shown that eating meals earlier in the day has positive health outcomes, and Johns Hopkins University recommends maintaining an approximate 12-hour eating window, eating a high-protein breakfast within 30 minutes of waking, lunch four hours after breakfast, dinner by 8 p.m., snacking between meals, and eating meals every three to four hours.2
Dr. Josiane Broussard of the Ruedman Family Center for Women’s Health Research at the University of Colorado Anschutz School of Medicine spoke about the impact of meal timing on cardiometabolic health and its impact on sleep, among other things.1
Broussard said. HCPLive Studies have found that eating during the biological night, which corresponds to nighttime for diurnal animals like humans and daytime for rodents, has adverse effects.
“We found that animals who were fed during that period had poorer cardiometabolic health. [such as] They are at higher risk for obesity and changes in blood sugar and insulin levels,” Broussard says.
At present, there is little evidence on how meal timing affects circadian rhythms, but research suggests that meal timing may affect rhythms in peripheral tissues.
As for how meal timing affects hormone regulation, Broussard says it depends on the hormone. For example, meal timing likely won’t affect melatonin or nocturnal growth hormone, but it could affect blood sugar levels, which are determined by food.
Meal timing also affects insulin sensitivity, as people who eat late at night are at higher risk of diabetes and obesity. These people tend to have lower insulin sensitivity.
Studies have shown that time-restricted eating lowers 24-hour blood sugar levels because it’s “packed into a smaller window of time during the day,” Broussard explained.
Many dietary studies have evaluated the potential benefits of restricting eating times to either early or late in the day, but results have been mixed, possibly because many of these studies did not consider food portion size.
“That’s the problem,” Broussard says. “Time-restricted eating may be beneficial, as the saying goes, but using it as a way to eat less may also be effective.”
References
- Broussard, J, Grant, L, McHill, A. Meal timing and cardiometabolic health: mechanistic outcomes. Session presented at SLEEP 2024. Houston, TX. June 1-5, 2024.
- Nairn, R. Timing is everything: why eating on a regular schedule supports overall well-being. Johns Hopkins University. December 9, 2024. https://wellbeing.jhu.edu/blog/2022/12/09/timing-is-everything-why-eating-on-a-regular-schedule-supports-overall-well-being/. Accessed June 7, 2024.
