Most of us follow consistent patterns in our routines and tend to categorize ourselves as either a morning person or a night owl.
Research is now showing that not all habits may actually be created equal as our daytime and nighttime routines can either contribute to our health and wellbeing or increase the risk for certain diseases.
Sleep deprivation is becoming a global health issue as the average sleep time is slowly decreasing and more and more people are not getting enough sleep on a regular basis (1)(2).
There is now strong evidence supporting the link between too little sleep and increased weight gain (3).
Sleep regulates many functions and processes in the body including hormones, glucose metabolism, and insulin function.
Lack of sleep can result in dysregulations of hormones associated with metabolism such as decreased glucose tolerance and insulin sensitivity, increased cortisol and ghrelin levels, decreased leptin levels, and increased hunger and appetite (4).
Being in a sleep deprived state can also make it more likely that you reach for not so healthy foods due to increased hunger and cravings.
But it's not just lack of sleep that may be contributing to the obesity epidemic and affecting your health, the time that you go to sleep may also play an influential role.
What does staying up late have to do with your weight?
Staying up late can interfere with the circadian rhythm, the body's internal clock that follows a 24 hour cycle and regulates the body's sleep-wake patterns.
Our circadian rhythm has been shown to be significantly influential on our health and can also impact the way our bodies utilize insulin and their fat burning efficiency.
This makes sense as the body follows the natural rhythm of the sun, optimizing different activities according to the time of day.
A recent study emphasized the association between sleep and metabolic health, finding that night owls experienced reduced fat burning and had an increased risk of insulin resistance and chronic disease (5).
Circadian misalignment can impact your ability to lose weight by modifying glucose and insulin metabolism, leptin and ghrelin levels, appetite, HPA axis activity, and as a result disturbing metabolic balance (6).
So what can prompt the circadian rhythm to be out of alignment?
Well, in addition to staying up late, eating late can also interfere with sleep and desynchronize the body's internal clock (7).
Eating later during the day, and especially at night, can result in more fat storage as well as increased insulin, fasting glucose, cholesterol, and triglyceride levels (8).
A study that assessed the effects of late night eating found that eating later in the day resulted in modified levels of hunger hormones that influence our desire to eat and decreased fat burning (9).
What's more, electronic use often goes hand in hand with night owls who might stay up late working on the computer, scrolling their phone, or watching TV.
This exposure to blue light only further dysregulates the circadian rhythm by suppressing melatonin and making it more difficult to fall asleep at night (10)(11).
Research suggests that melatonin may play a role in metabolic health and maintaining a healthy weight by balancing energy expenditure, regulating glucose tolerance, improving insulin sensitivity and reducing oxidative stress (12)(13).
Circadian alignment and sleep quantity and quality are all essential for overall health but also weight management.
The good news is that we can influence our circadian rhythm with our lifestyle choices such as meal patterns, physical activity, and sleep and wake times.
Wait, does this mean we all have to go to bed early? While early bedtime is ideal, if you recognize yourself as more of a night owl there are certain measures you can take to improve your sleep habits and circadian rhythm alignment in order to take care of your metabolic and long term health.
This may include timing your food intake to earlier in the day and avoiding heavy meals later at night.
Adopting a bedtime friendly night routine can also make a significant difference in your ability to have a good night's sleep and fall asleep earlier.
This may look like:
- Supplementing short-term with melatonin or a natural sleep support
- Include adaptogenic and calming herbs
- Avoiding electronic use 1-2 hours before bed
- Adopting calming activities in the evening such as reading, walks, bath, light yoga, or stretching
- Creating a sleep friendly environment by keeping your bed clean and tidy and the room dark, quiet, and cool
- Avoiding alcohol and caffeine later in the day and evening
- Having a light snack or bedtime tea if you tend to get hungry later
- Listening to a meditation or binaural beats
If you are someone who tends to go to bed very late you can try to start inching your bedtime earlier even if it's just by 15 minute increments.