Friday, May 10, 2013

Night eating--circadian rythm (150.8)

I read last week that researchers confirmed our circadian cycles affect our hunger.

Here is a link:
Study explains what triggers night-time food cravings

Bottom line:
The researchers found that the internal circadian system regulated hunger, with participants feeling the least hungry in the morning (8 a.m.) and most hungry in the evening (8 p.m.).


“Our study suggests that because of the internal circadian regulation of appetite, we have a natural tendency to skip breakfast in favor of larger meals in the evening. This pattern of food intake across the day is exactly what Sumo wrestlers do to gain weight.” said Steven Shea. “So, it seems likely that the internal circadian system helps with efficient food storage. While this may have been valuable throughout evolution, nowadays it is likely to contribute to the national epidemic of obesity.“
Here's another study: Circadian clock linked to obesity, diabetes, heart disease   This is a study on mice, which have similar molecular structures to ours.  Their cycles are a mirror image of ours--they are active at night, while we are inactive at night.    Bottom line: "Mouse tissues are relatively resistant to insulin [convert food to fat] during the inactive/fasting phase [our night time cycle].   "Whereas they become more sensitive to insulin (therefore better able to transfer glucose out of the blood [and NOT convert it to fat]) during the high activity/feeding phase [our day time ] of their 24-hour cycle.

"As a result, glucose is converted primarily into fat during the inactive phase and used for energy and to other tissue building during the high activity phase."

That is why it is good to fast every day…not eat anything between dinner and breakfast,” said Johnson [one of the researchers].   The take away?  I'm wired to eat at night.  I have to fight evolution to eat breakfast early and not eat the house down after 8 pm.     Of course we have practical, real life experience of the results of eating at night, although I have read health/fitness articles in the past that say it doesn't matter when you eat--a calorie is a calorie is a calorie.... calories in/calories out.  But that's simply not true, as evidenced by our experience and now by scientific research.     I guess it's helpful to understand the WHY's of my behavior.  But it's still a fight to change.  Thanks a bunch, evolution.

7 comments:

Jill said...

I keep saying lately that the knowing is so much easier than the doing. But at least now you know there is a reason that you are attracted to night eating - conquering it will come next. :)

I posted a short one today. Thanks for checking in with me - I've been struggling lately, but I think I'm coming around. :)

Laura N said...

I should note that I don't think these studies give us a pass to do what evolution tells us to do. Clearly, our bodies NOW need us to do the opposite of what we were conditioned to do for thousands of years. Diabetes, obesity, and heart disease aren't furthering the species.

This link has a great picture on page two, showing the relationship between the different kinds of adaptations we use. I didn't read the whole article. But it was interesting to note that environment, culture & technology, physiology & development, all play a part in genetic adaptation.

Vickie said...

I would add a reminder that PROTEIN is what holds us. I think it helps to have the last meal of the day be solidly packed with protein and light on carbs. If the last meal of the day has too many carbs and not enough protein, blood sugar goes up and then plummets and causes what we perceive as hunger.

Vickie said...

Happy Mother's Day to you!

Vickie said...

how is this week going? are you past your afters and your altitude (if that is what was getting you)?

Laura N said...

Hi Vickie, I'm writing a new post with info. Thanks for asking!

katie said...


May I suggest that you see an MD who specializes in psychopharmacology ( psychiatrist ). I do. I have had depression for 20 years ( I'm 55 ). I live in NYC and am an ANP. I refer patients to psych for psych meds. I myself struggled greatly with my depression until Effexor was invented (SNRI) . I too use Trazodone to fall asleep. Haven't has an episode of d. in 9 years on the right med ie Effexor. Psychopharm is an art. Consider finding an appropriate MD . You deserve it!