According to recent studies, there might be optimal times of day to eat and fast.
Two recent studies published in the journal Cell Metabolism suggest that eating earlier in the day may aid in weight loss and that consuming meals within a 10-hour window may enhance blood sugar and cholesterol levels.
Courtney Peterson, PhD, an associate professor of nutrition sciences at the University of Alabama in Birmingham, told NBC News that “you have this internal biological clock that makes you better at doing different tasks at different times of the day.” Peterson didn’t take part in the research.
She claimed that for the majority of people, mid- to late morning seems to be the optimal period for their metabolism.
In one study, researchers discovered that eating the identical meals later in the day made people feel more hungry over the course of a 24-hour period. Additionally, eating late resulted in adipose tissue that retained more calories and burnt calories at a slower rate. The authors of the study concluded that the alterations taken together may raise the risk of obesity.
Researchers discovered in another study that consuming meals within a 10-hour window decreased the size of harmful cholesterol particles, which may lower risk factors for heart disease, among firefighters working shift work. In people with health concerns like diabetes, high blood pressure, and high cholesterol, the 10-hour eating window also reduced blood pressure and blood sugar levels.
The results of the two new studies support those of earlier research that suggests humans may have a preferred eating window based on circadian rhythms, which control sleep and waking cycles and influence hunger, metabolism, and blood sugar levels.
The 10-hour window, for instance, seems to be a “sweet spot” for the body in the firefighter study, the investigators discovered. More stringent limits, like those present in many intermittent fasting regimens, may be hard for the body to sustain.
One of the study’s authors and a professor at the Salk Institute, Satchidananda Panda, PhD, told NBC News that while 6 or 8 hours would be beneficial, people might not stay with it for very long.
Despite having modest sample numbers, the new studies provide information for future study. In the first trial, two 24-hour feeding regimens were tested on 16 overweight or obese participants. Some of them started eating an hour after their normal wake-up time, while others didn’t start until over five hours later. The calories and nutrients in their meals were the same for both groups.
Leptin, a hormone that aids in the feeling of fullness, was found to be lower after eating later when the hormone’s levels were examined by the researchers. Additionally, eating later quadrupled the likelihood that patients would experience constant hunger. People in the research who ate later in the day also reported increased cravings for meat and dairy, which are foods high in energy, as well as starchy or salty items.
The research team also discovered changes in fat tissue, which may increase the likelihood of forming new fat cells and decrease the likelihood of fat burning. Around 60 fewer calories were burnt throughout the day by late diners than by early eaters.
When you consume calories later in the day, your body processes them differently. It tipped the scales in favour of weight and fat accumulation, according to Peterson. We can quite clearly conclude from this study that people shouldn’t skip breakfast.
The second study tracked 137 San Diego, California, firefighters who consumed a Mediterranean diet consisting of fish, vegetables, fruit, and olive oil for a period of 12 weeks. 70 of them—firefighters—ate throughout a 10-hour window, while the remaining individuals—firefighters—ate during a larger window, usually around 13 hours. They wore devices to monitor blood sugar levels and recorded their meals in an app.
Most of the firefighters in the 10-hour group ate between 8 and 9 in the morning and 6 or 7 in the evening. Time-restricted eating appears to be associated with health advantages such decreased heart disease risk and lessening of dangerous cholesterol buildup.
The time-restricted feeding programme reduced blood pressure and blood sugar levels in firefighters who had heart disease risk factors like high blood pressure and high blood sugar.
According to the scientists, the constrained window appears to provide the body a chance to eliminate toxins, salt, and other substances that could raise blood pressure and blood sugar levels.
The organs “receive some rest from processing food so they may divert their energy toward mending cells” during periods of fasting, according to Panda.
