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To Breakfast Or Not To Breakfast

We all have heard of the benefits of intermittent fasting and time restricted eating, but is there an optimal time to practice this? A new study Published February 27 in the open-access journal PLOS Biology, research conducted by Kevin Kelly, Owen McGuinness, Carl Johnson and colleagues of Vanderbilt University, USA shows that it's not just how many calories you eat, but when you eat them in relation to circadian rhythms that will determine how well you burn those calories.

Circadian rhythms, are the body’s 24-hour cycles of biological, hormonal, and behavioral patterns. These patterns work to control a wide array of bodily processes, including the production of important hormones that are responsible for the regulation of sleep, hunger, metabolism and many other processes.

While more research is needed, there recently was a small study that showed evidence that linking caloric intake to circadian rhythms can influence body weight via the effects on lipid oxidation (fat burning). Let’s look at the study to get insight to our question!

The study was conducted in two sessions and involved six healthy adults between the ages of 51 and 63 years old whose body mass indexes were between 22.2 and 33.4 (normal to obese). During the first session, the participants received three meals per day: breakfast (700 calories), lunch (600 calories), and dinner (1,000 calories).

In the second session, the participants instead of receiving breakfast, received a late-night (10 PM) meal (700 calories) which was the same calories as the breakfast that was skipped. So, on both occasions, caloric intake was exactly the same. The only difference was that rather than having 700-calorie breakfast, they had a 700-calorie late night meal. The overnight fast was approximately 14 hours on both occasions, so their “eating window” and overnight fast was the same number of hours. It is also important to note that activity levels were exactly the same between the sessions as well.

The study monitored the participants' metabolism via a whole-room respiratory chamber during the two sessions, which lasted 56 hours each. They found that eating a late-night meal rather than the isocaloric breakfast markedly altered the participants' capacity to burn fat. This shift in metabolism was driven by circadian rhythm-regulated metabolic patterns.

These findings suggest that late-night eating may drive body fat storage/accumulation and given the noted shifts in metabolic patterns, one could deduce that late night eating could subsequently increase risk for metabolic disorders such as type 2 diabetes.

Interesting, right!? Perhaps the age old saying “Early to bed and early to rise, makes a person healthy, wealthy and wise” is true (well, at least the healthy part)!

This was a very small study and more research is needed, but the findings are consistent with other works by researchers like Dr. Satchin Panda. I will say, however that there is enough evidence showing that practicing time restricted eating in general, whether or not your eating window is shifted earlier or later, still offers many benefits. In other words, it is better to practice time restricted feeding even if you eat late over not practicing it at all. Also, with this study being so small, it is hard to know if the results would apply to the majority. I wonder what the chronotype of the participants were. I wonder if those with the "night owl" chronotype would show similar results or if since that chronotype is shifted later, would they benefit more from eating later vs earlier? This study raises so many questions!

I for one, do not get home from clinic until about 7 pm, I then have to prepare and serve dinner to my family, so we eat around 7:30 or 8 pm. My eating window usually starts about 11 am or noon. I would not be able to start, or stop eating earlier, otherwise I wouldn't be able to share a meal with my family, which I believe is very important. For this reason I chose to take some benefit over none! How about you?

Are you a breakfast person or a late night snacker? Comment below!

Link to the study:


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