Chronobiology – WHEN you eat, sleep & exercise

What if when you eat, sleep and exercise is as important as what you eat, how long you sleep and what kind of exercise you do? Chronobiology is the study of the way our body responds to the cycles of the sun and moon, it’s a fascinating new area of research.

Life on earth has developed in the context of day and night. Sounds a bit obvious really, but when we think about the way we are changing our lifestyles due to late night Netflix, shift work, reduced amount of time outdoors, and constant grazing on snacks you might see how our bodies are getting out of rhythm with the way our body has evolved to work.

Chronobiology as an area of research isn’t really new, but it’s becoming more central to nutrition conversations I’m having or when I’m listening to nutrition experts talk.

Your body clock

You have two types of body clock, the SCN (suprachiasmatic nucleus), the master clock in our brain; and little clocks in all of our cells, called peripheral oscillator clocks.  If we get a mismatch between the two systems there is a higher risk of disease conditions.

This is why shift workers have a higher risk of cancers, obesity and other chronic health conditions. Their biological needs can become separated from their actions. Chronobiology can’t be erased from our genes however convenient it would be.  

The master clock is stimulated by light, which is why getting some daylight in the morning is important. The mini clocks in all our cells are trained by how we live, and our activities.

The mini clocks take cues from when we eat, when we are mentally alert (thinking, focused, or stressed), when we exercise, and when we sleep.

WHEN you eat is important – Chrononutrition

I talk about restricted feeding windows quite a bit (eating within a 10 hours of the day, and fasting for the rest). Some people do this earlier, say eating from 7 until 5, and some people later, say eating from 9-7). Research says the timing of when we eat is important because it can affect the clocks in our cells.

It’s better for our biology to eat earlier in the day, rather than late at night. Our circadian rhythms get delayed by late meals and snacks. This also has an impact on our sleep.

The clock in your gut

Our gut is home to trillions of microbes. These changes through the day, and move about inside our gut, and it’s these changes that can be influenced by the timing of our food and activity.

In research on mice scientists showed the regular tiny movements of bacteria can influence the circadian rhythms because different gut tissue was exposed to different microbes and the metabolites they make.

Some bacteria in our gut respond to the presence of food, others to the hormone melatonin.

Our digestion is primed to do it’s work during the daytime, not at night. At night the liver detox processes and our digestive juices aren’t primed to work.

Even our saliva slows down at night so we’re not breaking food down as well, the mechanical digestion process slows down.

Chronobiology – How to train your circadian rhythms

• Get outside in fresh air – 30 minutes minimum of daylight before noon will help set your master clock.
• Restrict blue light from screens, especially if you’re sensitive to it, or you haven’t been outside for at least 30 mins
• Stay active during the daytime.
• Don’t eat late at night – some research suggests cut off of 7pm, some says earlier.
• Keep to 3 meals a day, with no snacks in between
• Don’t save up your calories for one big meal
• Create a bedtime routine – no screens for 2 hours before bed, reduce stress, focus on calm down

If you struggle with insomnia, weight loss or chronic health conditions like heart disease, diabetes or high blood pressure you could take a look at your routines, and see how you can start adapting to fit better with the way our body has evolved.