“Sitting here in my lab, I can imagine you scratching your head again: Dr. Panda, what’s the big deal? Aren’t we talking about just a few ounces of fat gain after a late-night snack? Won’t my metabolic rhythm come back the next day? Actually, it’s worse than you think. It is hard enough for the body to monitor hormones, genes, and clocks for someone with a strict eating routine. But when eating occurs at random times throughout the day and night, the fat-making process stays on all the time. At the same time, glucose created from digested carbohydrates floods our blood and the liver becomes inefficient in its ability to absorb glucose. If this continues for a few days, blood glucose continues to rise and reaches the danger zone of prediabetes or diabetes. So, if you’ve wondered why diets haven’t worked for you before, timing might be the reason. Even if you were diligently exercising; counting calories; avoiding fats, carbs, and sweets; and piling on the protein, it’s quite likely that you weren’t respecting your circadian clocks. If you eat late at night or start breakfast at a wildly different time each morning, you are constantly throwing your body out of sync. Don’t worry, the fix is equally simple: Just set an eating routine and stick to it. Timing is everything.”

“Our modern lifestyle, in which we spend most of our time indoors looking at bright screens and turn on bright lights at night, activates melanopsin at the wrong times of day and night, which then disrupts our circadian rhythms and reduces the production of the sleep hormone melatonin; as a result, we cannot get restorative sleep. When we wake up the next day and spend most of the day indoors, the dim indoor light cannot fully activate melanopsin, which means that we cannot align our circadian clock to the day-night cycle, making us feel sleepy and less alert. After a few days or weeks, we get into depression and anxiety.”

“lots of light during the day, no light at night, less noise, relatively cooler temperatures at night, and earlier dinner. Each of these factors has been shown to contribute to better sleep.”

― Satchin Panda, The Circadian Code

Lock in Your Feeding Window

Maybe the biggest lever we have to establish our circadian code is when we begin and finish eating each day.

Dr. Panda recommends eating your first calories about 30 – 45 mins after you get up in the morning and finishing your eating 3 – 4 hours before you go to bed. Ideally, this will all be done within an 8 to 10-hour window of time. But, like so many things when it comes to nutrition what works best for a person can vary greatly.

At a minimum, we really should not be consuming any calories outside of a 12-hour window. A shorthand for this could also simply be “only eat when the sun is shining.” When the sun stops for the day so does our eating pattern.

I have been a fan of time-restricted eating (TRE) for quite some time. Usually, this meant skipping breakfast and eating my first meal at lunch, and stopping the feeding window at 7:30 or so. However, I have changed this pattern some.

Since I work out in the mornings, I have begun to take in about 30 grams of protein around 8:30 am. This is about 30 minutes after I have finished working out (yay!) but about 3 hours after I first wake (boo). But, I prefer to do my strength training and running while fasting so 🤷‍♂️. So far I am seeing the benefits.

Since I start my feeding window at 8:30 am I try to stop eating around 6:30 at the latest. Of course, with family schedules at time, this is difficult but I am trying to make it a priority.

Being Consistent Is Key

Once you lock in your feeding pattern, it becomes a little easier to time your sleep. Since I am usually finished eating around 6:30 pm it means my system is ready for sleep by my 10 pm bedtime.

I try to get the kids in bed, the kitchen cleaned up and teeth brushed in time so I can be in bed by 10 pm. Am I 100% successful? LOL. No. But I am usually pretty close. If I can be in bed at 10 pm, it allows me to read for a few minutes before lights out at or around 10:30 pm.

The alarm is going off by 5:15 am each morning, to give me time to go through my morning rhythms of reading, meditation, and working out. Being consistent with this routine helps reinforce my circadian code.

I can see benefits pay off in my health metrics. My HRV is higher, my breathing and sleeping heart rates are lower, and my blood O2 level is higher. And all of this occurs even without me getting the total amount of recommended sleep. That’s right, if you are really paying attention and did the math, it means on average I am only getting about 6.5 to 7 hours of sleep each night – less than the recommended amount. This is a puzzle I haven’t yet solved.

I Have a Bedtime, So Do My Devices

It is fair to say that the biggest disrupter of our circadian code is likely screen time. We spend WAY too much time staring at these magical little devices. So in part to establish some boundaries and in part to improve my sleep I put my phone to bed at least an hour before I do.

This means by 9 pm, I have checked all the emails, returned all the messages, and looked up anything online that I plan to do for the day. The rest of the evening to given to time with my family, watching a show with my wife (yes, still screen time but not quite as detrimental to sleep), or reading.

This change alone is powerful enough for people to see improvements in the ability to fall asleep more quickly and sleep more soundly each night.

Dr. Panda goes on in the book to outline the reasons why these practices are so beneficial. If you are seeking to improve your health and wellness or if you suffer from a disrupted sleep pattern, The Circadian Code is a great place to start in order to understand the factors that contribute to this foundational health practice.