Internal time clock also regulates things such as weight gain

Your first cup of coffee early in the morning or that late night bowl of cereal before bed may be killing your diet.

For people trying to lose weight, when you eat may be just as important as what you eat.

Dr. Satchin Panda of the Salk Institute for Biological Studies has conducted some fascinating research on circadian rhythms and how they affect many aspects of life, including weight management.

According to Panda, the light sensors in our eyes set the internal clock that keeps us on track. When external stimuli are altered by things such as artificial lighting, we tend to fall out of sync. Specifically, Panda has identified a blue light sensor in the retina that sets the time for wakefulness and sleep.

It seems our internal time clock also regulates things such as weight gain. Panda examined two sets of mice — one group that ate within a 12-hour window and another whose eating was unrestricted. Both groups ate the same number of calories derived from a North American diet.

The mice that adhered to a restricted regimen were much healthier and slimmer than the group that grazed beyond the 12-hour period. The unrestricted mice then lost weight when placed on the same diet as their fitter siblings.

Just as important, Panda has also linked the circadian clock to immune system health.

Trials have already begun to determine whether similar outcomes can be replicated in human subjects. Early results suggest that time-restricted eating may help to remedy ailments such as high cholesterol, diabetes, obesity and more.

For now, Panda recommends eating within an eight- to 12-hour period. Remember, your clock starts as soon as you ingest anything beyond water. That means a sip of coffee in the wee hours and a healthy carrot munched late at night all count toward your total since they demand processing and stimulate your system.

Similar but different from intermittent fasting (a popular form of calorie restriction), time-restricted eating tends to be more accessible for the average person. Simpler is always better as we humans tend to have a hard time sticking to the basics. (Subjects in human studies claim to be eating within the restricted 12-hour window but data collected by Panda proved otherwise.)

Accessibility stems from the fact that protocols don’t require participants to change the content of their diet — although doing so will only enhance results. Simply tighten up your feeding window by avoiding post-dinner snacking, assuming dinner is only 8-12 hours from your first morning ingestion. You may need to shift your morning coffee or tea by an hour or so.

Note that the 12-hour protocol works great but it seems that improvements to muscle gain and endurance tend to occur closer to the eight-hour mark.

Those of you who like to unwind after a long week (everyone) will be happy to know that researchers factored a few “cheat days” into their protocol. On weekends, don’t go crazy but feel free to relax regular Monday-to-Friday restrictions.

Time-restricted eating is a great way to initiate your wellness journey because it doesn’t require complicated formulas, food-group restrictions or starvation. Sure, if you’ve always grabbed a late-night snack it may take some time to adjust. Know that you are often eating out of habit or boredom. To compensate, ensure you eat enough throughout the day and that you are engaged in some form of activity. (Remember, TV is continually transmitting food messages which makes calorie restriction very challenging.)

Other than weight loss, the real win in all of this is learning to manage change. If you can master this one adjustment, you are better prepared to tackle more complicated challenges such as healthier food selection and exercise.

If you are contemplating one of the popular weight loss diets to lose weight for the summer, consider time-restricted eating for something a little less onerous.

For a great overview of time-restricted eating, check out Dr. Panda’s Ted talk on YouTube, entitled Health lies in healthy circadian habits. There are also various practical support tools available such as apps to make things a little easier. For those who like research, there are many studies available through Dr. Panda’s website at

Before starting any diet, examine a variety of sources and consider the approach that seems to address your specific needs. Be a little skeptical, ask questions, adjust where appropriate and stay the course.

Remember, if you “kinda” manage your diet, you will “kinda” lose weight.

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