Chrono-nutrition is a term coined in 2013 by Dr Shigenobu Shibata from Waseda University in Japan.

Loosely speaking, what he and his team found was that ‘eating’ was linked to the circadian rhythm.

Tightly speaking, Dr Shibata and his team found that plant estrogen applied to mouse livers in a lab could alter the length of the circadian rhythm.

Over subsequent years, researchers became interested in the timing of one’s eating during the day, and its effects on weight and sleep.

Somewhere along the line - Dr Shibata’s version of ‘Chrono-nutrition’ - which was based on animal research and circadian rhythm length - merged with this human being meal timing research.

If you’re confused by all this - don’t worry - so am I. But I’ll try to break it down for you …

The Original Chrono-Nutrition

Hopefully you’ve heard of the body clock, right?

It sits in the middle of the brain and primarily receives light and dark signals from our eyes. Light signals - timed relative to one’s chronotype - can alter the timing of their circadian rhythm.

But other biological clocks have been found in our body - in other organs.

And one of these suggests that circadian rhythm timing can change when humans eat at certain times relative to their chronotype.

But what Dr Shibata proposes is very interesting (at least to me).

He suggests that the length of the circadian rhythm can be altered by ‘eating’.

For example, if the length of the circadian rhythm is made shorter - and stays shorter on a regular basis - then one’s circadian rhythm timing becomes earlier.

This concept is quite different to what many believe from …

The New Version of Chrono-Nutrition

… which is that if you eat a big meal at the end of the day, then that’s bad.

The proposal is that our bodies are not built to process big meals at the end of the day, thus there is an increased likelihood that we’ll put on weight.

Instead, good Chrono-nutrition is to eat big at the beginning of the day, which will give you more time to burn those calories before hitting the sack.

For a good review of this new version of Chrono-nutrition, one can read the following study …

But Wait, There’s More …

This month, a new study was released that suggests the new version of Chrono-Nutrition is bullshit.

This new study randomised people to either a morning-loaded diet or an evening-loaded diet.

The researchers found no difference between the two diets.

Both diets produced similar levels of energy expenditure and similar levels of metabolism.

And by the end of the study, there was no differences in weight between the two diets.

However, as I often keep preaching to people - this is just one study - so we cannot conclude that the new version of Chrono-nutrition is 100% bullshit.

But there was something I noticed about this new study that wasn’t necessarily being picked up by other commentators.

Yo-Yo-ing

If you look closely at who the researchers were of this new study - and then look back at some of the other chrono-nutrition studies (hint: looks at the last image in this blog), then you’ve just played a game of ‘Spot The Similarity’.

Jonathan Johnston (try saying his name 10 times in a row …) is a Professor of Chronobiology at the University of Surrey - where some of the best circadian rhythm researchers in the world do their stuff.

Prof JJ has published a number of scientific papers about the potential benefits of a morning-loaded diet.

Yet he is an author on the latest study showing no differences on a range of physiological markers of Chrono-nutrition.

This may not yet be a complete backflip, but more so the beginning of a sleep researcher’s evolving belief about how our sleep world works.

I’ve had to do the same when in 2010 I developed a theory for how technology use affects sleep (if this is the 1st blog you’re reading of mine, you may need to read a bunch of others to get what I mean).

Recently, Prof Matthew Walker has evolved his beliefs about the type of things that can affect sleep.

And there are other sleep researchers who have done the same.

Conclusion

Google Scholar shows 833 results for ‘chrono-nutrition’.

Google shows 539 … times the above amount of results.

What’s fascinating is the number of ‘wellness coaches’ and ‘biohackers’ that are blogging and podcasting about chrono-nutrition.

Will they evolve their beliefs about sleep?

The answer probably lies somewhere between ‘not yet’ and ‘not ever’.

Even today I saw yet another post about how bad blue screenlight is for sleep. That there’s a 79% reduction in the time taken to fall asleep from using blue-blocking glasses (no scientific study cited - but you can buy a pair of BB glasses from their shop).

And there’s plenty of peeps bagging the crap out of melatonin, making it out to be a poison - whilst in other posts saluting to the camera with a glass of ethanol. Child deaths from alcohol are more than 1,000-fold than those from melatonin - study says.

We live in a digital world fertilising misinformation, which makes it hard to find facts. Finding a scientific fact these days is like searching for a needle in a bunch of needles.

But once facts are discovered, the question is - will you evolve your beliefs about how sleep works?

• Prof MG