1 Out Of 3 People Should Not Eat Before Bed
In my six year experience as a personal trainer, I am constantly asked if we should be eating past a certain time. When I am asked the question, the client expects a quick yes or no answer. Unfortunately, it is not a black or white. From a calorie perspective, the timing of food has minimal importance. The most important factor is a caloric balance. But, nothing in life operates in a vacuum. We can't just look at calories in versus calories out when we are focused on overall health. We must look broader and include all the pillars of health.
There are four pillars of health you must pay attention to in order to live a long, healthy life. They are nutrition, recovery, community, and fitness. You don't have to be perfect in each one, but you shouldn't neglect one either. So when looking at a diet, we must ask ourselves how it affects the other pillars. Obviously, if you don't eat past a certain time it can limit your social life which can impact the sense of community you have. As I stated above, eating before bed won't increase body fat unless you are in a caloric surplus. In fact, some studies have shown eating protein before bed can help preserve muscle mass (1,2 ). But what about sleep and recovery? Will eating too much before bed impact our sleep quality?
For the last five years, I have fasted in the morning and saved my calories for later in the day. I used to eat the majority of my calories at night because it was easy to limit my calories during the day. I enjoyed my morning black coffee and didn't need breakfast because I was still full from the night before. I would wake up feeling refreshed, but I was in my early 20s. I could go out, have five tequila shots and wake up feeling refreshed on only five hours of sleep. So, feeling refreshed every morning was quite easy to do. Therefore, you have to take my experience with a grain of salt. As I have gotten older, I have found a big meal before bed disrupts my sleep. My body overheats and I wake up in the middle of the night. But for some of my clients, a huge meal will make them sleep like a baby. So what gives? Why can some people eat before bed and sleep well, while others can't?
One day I was listening to the Foundmyfitness podcast hosted by Dr. Rhonda Patrick. Her guest for the episode was Dr. Satchin Panda, an expert on time-restricted feeding i.e. eating from 9 am to 5 pm. During the episode, I learned that insulin is inhibited by the sleep hormone melatonin. Insulin is a hormone responsible for regulating the amount of glucose in the blood. When you consume too many calories in the form of protein and carbohydrates the body has to secrete insulin to keep blood glucose levels in check. Carbohydrates followed by protein cause the highest insulin release, while fat has the least impact. However, fat has two times the amount of calories per gram (9 calories versus 4 calories) so you must monitor serving sizes and intake. The sleep hormone melatonin is activated at night when the eye is exposed to dim light. The dim light signals to the body to start the sleep process. As I stated above, the starting of the sleep process inhibits the body’s ability to use insulin. Put simply, it is a bad idea to eat a high carbohydrate and high protein meal in the dark.
I was convinced that I needed to switch things around and eat the majority of my calories during the day and early evening. Since making the switch, my sleep and energy levels have improved. I wake up feeling more energized and focused. My mind is clear and ready to take on the day. There are still days where I eat too much or lack willpower and indulge. Those are the mornings where I feel lethargic and foggy. My mind seems to be lagging and more caffeine is needed to get through the day. As the months have gone by, the correlation has grown stronger. Whenever I have a meal high in calories and carbohydrates I wake up feeling sluggish. Now, I am not saying carbohydrates are bad for you. A high protein and fat meal cause the same thing. In fact, last week I had half a pound of pork belly and a third pound of steak. I didn’t sleep well that night, to say the least. The formula for a poor night’s sleep is as simple as this: too many calories plus too many insulinogenic foods (i.e. whey protein, fruit, processed foods, grains); if only health came down to simple formulas. Unfortunately, this couldn’t be further from the truth. What works for me, may not work for you.
According to a study published in Cell Metabolism, about 1 out of 3 people ( 30%) of the population may have a pancreas that is more sensitive to the insulin-inhibiting effects of melatonin. In the study, they found out that the MTNR1B gene alters the number of melatonin receptors. The increase in receptors leads to higher melatonin levels. (3). Since melatonin inhibits insulin, a high carbohydrate meal after 9 pm would cause hyperglycemia (excessive glucose in the blood) which would put you at a greater risk for type 2 diabetes. And guess what, I have the MTNR1B gene. So maybe that is why I can't have a big meal before bed. The higher melatonin levels inhibit insulin release and cause hyperglycemia. I would hypothesize that too much glucose in the blood at night would alter the circadian rhythm.
A dysfunctional circadian rhythm can cause all types of problems. From a lack of energy to increased calorie consumption and anxiety to name a few. As you can see from the infographic, a functional circadian rhythm is essential for health. It controls hunger, energy levels, and everything in between. So for me and others who have the gene, it would be wise to avoid a big meal before bed. Do you struggle to sleep after a big meal? If so, then you might be one of the three who has the gene for higher melatonin levels. I recommend limiting your meals to the morning and early evening. And if you want to know for sure you can get your DNA tested through 23andme.com to find out.
- Melatonin secretion starts at 9pm and ends at 7:30am
- Melatonin inhibits the body's ability to use insulin
- People who have the MTNR1B gene should avoid a high carbohydrate meal before bed
- People who have the MTNR1B gene should avoid eating past 8pm
- Foods higher in protein and fats should be consumed before bed, but portion size must be controlled for
- Tim Snijders, Peter T Res, Joey SJ Smeets, Stephan van Vliet, Janneau van Kranenburg, Kamiel Maase, Arie K Kies, Lex B Verdijk, Luc JC van Loon; Protein Ingestion before Sleep Increases Muscle Mass and Strength Gains during Prolonged Resistance-Type Exercise Training in Healthy Young Men, The Journal of Nutrition, Volume 145, Issue 6, 1 June 2015, Pages 1178–1184, https://doi.org/10.3945/jn.114.208371
- Trommelen J, van Loon LJC. Pre-Sleep Protein Ingestion to Improve the Skeletal Muscle Adaptive Response to Exercise Training. Nutrients. 2016;8(12):763. doi:10.3390/nu8120763.
- Cell Metab. 2016 Jun 14;23(6):1067-1077. Increased Melatonin Signaling Is a Risk Factor for Type 2 Diabetes.Tuomi T, Nagorny CLF, Singh P, Bennet H, Yu Q, Alenkvist I, Isomaa B, Östman B, Söderström J, Pesonen AK, et al. doi: 10.1016/j.cmet.2016.04.009. Epub 2016 May 12. PubMed PMID: 27185156