Chrononutrition: How your sleep pattern influences your food choices
We’ve all been told that 7-8 hours of sleep seems to be the magical number that we should be aiming for to give our body enough rest. But a regular sleep pattern is just as important as getting the actual duration of sleep. For many this can be tricky to achieve with modern life getting busier and more stressful, and especially for athletes often early morning or late-night sessions are the only way to keep up the training load needed to prepare for competition (or are simply the only times you can manage to actually get into the gym while also juggling a fulltime job, looking after the family, seeing friends, doing your household chores etc). Which means we often end up not going to sleep or waking up around the same time each day. But what affect does an irregular sleep pattern have on us (aside from feeling like a zombie in the morning before that first cup of coffee)?
Let’s start off with your body’s own internal clock. Whether you are an early riser or a night owl, your body actually runs on an internal clock which is regulated by light (ie the sun). It naturally starts producing melatonin (the sleepy hormone) when it is dark (not instantly, usually around 9pm) sending your brain signals that it’s time to sleep. Similarly, when it gets light in the morning your body will pick up on this and cease melatonin production (usually around 7:30 am) and send signals for you to wake up. This will however be affected if you spend a lot of time in front of screens, especially watching TV or checking your phone frequently. The blue light emitted from the screen will throw of your body and actually delay the onset of melatonin, making you feel less sleepy and hence less likely to go to bed early.
Your body loves routine. It likes to know what to expect, so having a regular bedtime routine is actually one of the best things you can do for your body. Establishing a set sleep schedules means your body knows what to expect throughout the day so it can send out specific signals accordingly (ie releasing different hormones related to hunger, sleep etc). Most of us probably do not actually have a sleep pattern that we follow through with the whole week. While we might wake up & go to bed around the same time during the week because of work, on the weekends we usually like to treat ourselves to a little lie in. Now while that might seem like you are doing something good for your body because you are allowing it to sleep longer, it actually leads to something known as “social jetlag”. What that means is that your sleep midpoint has changed. If for example during the week you go to bed at 10:30 pm and wake up at 6:30 am your midpoint would be at 2:30am. On the weekend you might stay up a little later until let’s say 12:00 am and then wake up at 9:00 am. Your midpoint for that period would now be 4:30 am (2 hours later than during the week). Your body finds that very confusing and gets some of the signals it would usually send you throughout the day muddled up. Eating habits & sleep patterns
Studies have found that those who experience higher social jetlag (a difference in that sleep midpoint of more than one hour) actually had a higher consumption of overall calories, protein, fat, saturated fat, cholesterol, meet, eggs and sweets. They also often consumed more alcohol, had lower levels of physical activity and were more at risk of being overweight. What was interesting as well is that those who experienced greater social jetlag also generally ate their breakfasts later, shifting their entire daily eating routine further back and actually leading to them eating more and over a longer period of time. They would also often eat later at night, raising their insulin levels which would then interfere with the melatonin in their body. Eating later in the day also seemed to impact their microbiota (the bacteria in your gut) in a negative way. So how can we avoid this?
· Establish a bedtime and morning routine to help maintain a regular sleeping pattern that you can also stick to on (most) weekends
· Limit screen time in the hour before you go to sleep to help you fall asleep faster
· Leave the blinds open to help you wake up in the morning and avoid hitting that snooze button
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