Time-Restricted Eating – The Secret of Health & Longevity
What Is Time-Restricted Eating?
Time-restricted eating (TRE) refers to limiting food and beverage intake to certain hours of the day without attempting to reduce caloric intake. TRE is not a diet, it is a lifestyle. The focus for time-restricted eating is on aligning the times that you eat with your body’s innate 24-hour circadian rhythm. That means maintaining a regular and consistent eating schedule along with regular fasting periods every day or most days.
Researchers at the Regulatory Biology Laboratory at the Salk Institute for Biological Studies discovered that when you eat may be as important as what you eat. Time-restricted eating gives the body much-needed downtime during which it can undertake cellular repair and restoration rather than digestion. The researchers at the Salk Institute performed an experiment with genetically identical mice focused exclusively on the time restriction for feeding the mice. They gave one group of mice 24-hour, 7 day a week access to a high-fat, high-sugar diet. The other group had access to the same amount of food, but they had to eat all their food in an 8-hour window. Over the first 12 weeks of the study, the mice on a 24/7 schedule gained weight and developed health issues while mice on an 8-hour schedule were completely protected from the diseases normally seen with a poor diet. After 18 weeks, it was found that the mice who followed the 8-hour eating window weighed 28% less on average and improved their glucose tolerance.
Dr Satchin Panda, the lead scientist of the study, commented that the time-restricted eating mice lost weight and had normal blood sugar and cholesterol level. Dr Panda concludes: “Remember we did not change the diet and we did not reduce their calories. Timing made the magic”.
While this study was in mice, studies involving humans have shown that TRE has also resulted in improved overall health.
Benefits of Time-Restricted Eating
Time-restricted eating, when done the right way, elicits powerful health benefits. Dr Panda and other researchers discovered that maintaining a daily feeding-fasting cycle can prevent and reverse many chronic diseases such as cancer, diabetes, and dementia and microbiome conditions like acid reflux, heartburn, and irritable bowel disease.
Some of the proven benefits of TRE in both animal studies and human trials include:
- Enhanced weight loss and reduced fat mass
- Increased lean muscle mass and tissue
- Improved sleep
- Improved blood sugar control and 24-hour glucose levels
- Reduced inflammation–a key marker of longevity
- Improved heart function and cardiometabolic health
- Reduced metabolic disease
- Healthy liver function
- Improved brain health and cognitive function
- Improved ketone body productionIncreased energy
- Delayed aging and increased lifespan
Optimal Time to Utilize Time-Restricted Eating
Time-restricted eating is not about counting calories; it is solely about when you eat. You still need to eat healthy, unprocessed, whole foods, but within a compressed feeling window. Dr. Panda found the best results for weight loss are after a full 12 hours of fasting. That means a 12-hour compressed feeding window followed by 12 hours of fasting. After you incorporate the 12-hour fasting practice for a while, see how you feel and whether you may want to try a longer fasting time. A common version of time-restricted eating is so-called “16:8” fasting where all of the day’s calories are consumed within an 8-hour window, leaving 16 hours for fasting, including the hours during which a person is asleep.
There is no strict rule about when during the 24-hour cycle it is best to fast. However, sticking to a consistent feeding-fasting cycle is important. Dr. Panda’s research shows it’s better to eat a more carb-heavy meal the first half of the day when insulin response is better. Personally, the easiest way for me to incorporate TRE is to eat breakfast later and dinner earlier. Most likely, you will find that your system adjusts to the new timing within 2 to 4 weeks of being on TRE.
Some researchers including Dr. Satchin Panda believe that the moment you drink any beverages that are not water, such as tea or coffee, you break your overnight fast. The hypothesis is that the taste of anything, including tea or coffee, can cause the release of certain hormones that either make you hungry or may disrupt some of the circadian rhythm and autophagy benefits of TRE.
A word of caution: although time-restricted eating health benefits are powerful, discuss your plans with your health care practitioner. Those with blood sugar imbalances or hormonal issues may need to address these issues first before embarking on a time-restricted eating plan.
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