Losing weight is really a big challenge. There are no shortcuts, as it is all about consistency and discipline on what and how much to eat. And now, a mice study even suggests that there is a specified time of the day that can further help in losing weight. 

Aside from regulating your food consumption, you need to consider the time you eat your food, as metabolism is all about perfect timing. Health experts derived the conclusion that metabolism works best when eating is time-restricted to fixed hours close to daylight. Well, at least for mice, for now. 

How do time-restricted eating habits reduce weight? 

If your goal is to lose weight, a study on mice recommends eating all your food in an eight-hour time period and not eating snacks at night. When you are eating late at night, you may upset your rhythm of fat storage for energy, and this means late-night munchies create a disproportionate buildup of energy and weight gain. Plus, eating your food before the night has an impact on your metabolism, as light exposure can directly influence metabolic functions, like digestion and energy storage.

The animal research was focused on determining the possibility of time-restricted eating in loss gain in obese mice. Over the course of the day, your metabolic rhythm can change as it is heavily dependent on your eating time. Thus, the researchers are interested in studying the optimal time of eating within the rhythm if it can prevent weight gain. The term used to define the method is time-restricted feeding (TRF). Around 400 mice were studied for up to 26 weeks in a series of clinical experiments. The mice were divided into different sets that were given unrestricted eating time with access to high-fat food in 24 hours, high-fat food, high-sugar food, low-fat and high-fruit sugar foods, and another group of mice were in time-restricted eating. 

At the end of the experiment, mice that experienced time-restricted eating gained less weight compared with the other groups [1, 2]. It was concluded that the results significantly highlight the huge potential for TRF in counteracting obesity and including its metabolic disorders. Eating at inappropriate times can cause the burning of fewer fat cells, which are responsible for storing fat and connective tissue work. The mice study further suggests that any modification in circadian rhythms can make changes in metabolism, which can further lead to obesity. In some other studies related to eating habits, it was found that irregular eating habits can possibly affect metabolism control and impair thermogenesis –referring to the process of burning fat cells [3]. However, this is yet to be studied in humans. 

The research on mice under TRF in 2019 was conducted by the research fellows at the Salk Institute for Biological Studies in La Jolla and the University of California. Moreover, the work was funded by the US National Institutes for Health, and they also received grants from several institutions. It was published in Cell Metabolism, a peer-reviewed medical journal. 

Syncing your metabolic systems and circadian rhythms

Thermogenesis is an important aspect of the mice study. It refers to the dissipation of energy through the production of heat. The mouse’s feeding cycle is determined as antipodal to a human’s active phase of a daily eating cycle, considering that they are nocturnal. 

During high activity time of their circadian rhythm, mice were fed to fuel energy on their activities, and eventually, the researchers found that their weights remained stable. Meanwhile, eating high-fat foods in inactive times can lower the protein metabolism process in them. Furthermore, cells that specialise in fat storage tend to work better with rhythmic patterns aligning with the mice’s circadian rhythm. The researchers also believe that TRF is the most efficient way of processing nutrients while simultaneously maintaining fat cells stable.

Your built-in circadian rhythm directly influences your mind and the way your body behaves. There is a microbiological clock that allows your body to be coordinated in performing everyday tasks. At a more molecular level, your body has a circadian oscillator which are certain cell groups that collaborate to cause a larger system of mind and body to function depending on your everyday rhythm–it is like a mechanism of a clock. When you eat at a certain time that is misaligned with your body clocks, you may disrupt your thermogenesis. Consequently, it can put you at risk of obesity and other associated metabolic syndromes, such as high blood pressure and high blood sugar [4].

Do mice study similar to humans?

There are numerous studies on weight gain and weight loss, and they have been conducted by scientists for centuries, using mice as their preferred subjects of biological experimentation. Although there are a lot of anatomical differences between mice and humans, they can be great specimens when you study weight gain considering their small size. Also, mice do not need a lot of food for them to double their size.

Apparently, the slow-burning of fat cells statement in the mice study is relatively similar to how our body works as the metabolic activities of mice and humans are expected to slow down at their individual nocturnal phases of activity. Nonetheless, at the end of the day, we are far from looking like mice. Most certainly not, but on the other side, our human genome and the mice are almost identical, with only over 1 percent difference. Additionally, chimpanzees can also be a better subject model for the study as they are much more related to humans in many ways besides the molecular similarities.

Moving forward with the mice study

The number of obesity cases in humans is continuously increasing. With an extensive understanding of the ways to master our body clocks and instruct our cell protein buildup in tissues and organs, the mice study provides a very persuading theory that circadian rhythms can affect our biophysical functions. Looking at the mice study in a general sense, it is no surprise that the sleep-wake cycle can influence one’s metabolic activities, as it is a well-known fact that rhythmic thermogenesis supplies energy to living tissue and cells that are responsible for fat storage, depending on your day-to-day activities. 

It can only be a study conducted in mice, but generally, during docile human times, your body, though still mildly active, does not need to expend energy and, thus, would burn fat cells at a significantly slower rate. Thinking more about it, it makes sense because all animals living on Earth, including us, are almost all biological, physiological and behavioural processes–at the molecular level–follow the planet’s 24-hour clock, including heart rate, body temperature and hormones.

The stage of the mice research is considerably limited in application for human participants. Classic research studies on weight gain and obesity have already established that high-fat and high-sugar diets can significantly cause weight gain [5]. In future human clinical trials of TRF, it may be a randomised controlled study, showing that the amount of weight gain is much higher if the calories consumed are at particular times when the person does not make the most of his natural metabolic rhythm. Still, the best way to combat obesity is through consistently eating well-balanced diets and taking regular exercise or workouts. 

Moving from mice to humans, the researchers may have corroborating information to follow. For example, randomised, controlled and clinical trials in patients with obesity give us the information that obese people who follow time-restricted eating measures can successfully lose weight and enhance their heart health. In addition, aside from weight control, TRF can also possibly improve blood pressure and stress and provide some protection against type 2 diabetes [6].

Mice study on longevity

Overall, in the mice study, TRF can cause up to 12 percent loss in weight in mice that are already considered obese. Additionally, mice who were fed a healthy and normal diet while following TRF showed no weight gain. These results can contribute to anti-aging research, considering that weight is an important factor in health issues. Also, the relationship between one’s age and weight is quite close, meaning when you age, you are more at risk of gaining more weight due to possible years of a sedentary lifestyle, less muscle mass and some acquired medical conditions. The results of the mice study are much more valuable when further conducted in human trials. 

Being overweight or obese can lead to fatal diseases that may hinder your healthy longevity. If not managed properly, you may acquire diabetes, heart disease, cardiovascular disease and certain types of cancer. Plus, people with obesity, with BMIs of more than 30, tend to only live up to 77.7 years old, while those with 25 to 29.9 can live up to 80.8 years [7]. The time-restricted eating method may help in boosting your health span by keeping your body in good shape and protecting you from acquiring such deadly diseases. With TRF, you can minimally gain weight which is a good weight management strategy. 

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3491655/ 
[2] https://www.sciencedirect.com/science/article/pii/S1550413118305059
[3] https://pubmed.ncbi.nlm.nih.gov/27305952/ 
[4] https://www.nicswell.co.uk/health-news/do-time-restricted-eating-habits-reduce-obesity 
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6959843/ 
[6] https://www.cell.com/cell-metabolism/fulltext/S1550-4131(18)30253-5 
[7] https://www.aarp.org/health/conditions-treatments/info-2022/weight-and-longevity.html#