Wednesday, May 30, 2012

When it comes to weight loss, timing is everything

It doesn’t matter how late you eat it’s the calories in the entire day, right? Nope, sorry to say that’s another one of those weight-related rumors that can be filed in wouldn’t-that-be-nice along with “a calorie is a calorie” and “everything in moderation.” When it comes to weight loss, when you eat may be as important as what you eat and is often overlooked.

A friend sent me a link to an LA Times article “Nighttime fasting may foster weight loss”  that discusses a study recently published in the journal Cell Metabolism. Researchers at the Salk Institute placed mice on different eating regimens for 100 days. One group, fed a high-fat, high-calorie diet, could eat their food whenever they wanted. Another group was given only an 8-hour window to eat their food. The differences were staggering. The group with the unhealthy diet and no time restriction became obese and encountered a host of metabolic problems even though calories and fat were approximately the same as the “8-hour” group. Furthermore, the time-restricted high calorie group was almost as lean as the control group eating regular food after 100 days. Not only was the time-limited group better off than the grazing group, they almost fared as well as those eating a healthier diet.

If you’re starting to roll your eyes and thinking that this is one study and we’re not rodents, I hear you but this is not the first we’ve heard of this. A study from 2009 found that eating at times we should be resting leads to more weight gain than daytime eating. Just as we’ve come to accept that sleep plays a role in metabolism, we may now need to realize that our metabolic pathways and digestive system need sleep or at least rest. 

In terms of putting these findings to the test, I’m not sure we need 16 hours food free. Though not impossible, we could eat breakfast at 10am and dinner at 6pm, this can be a stretch. If you’re a nighttime nosher, try the 12 hour rule; whether it’s 7pm  to 7am or 8pm to 8am, try to keep 12 hours food free. And speaking of noshing, the nutrition content of our food generally decreases the later it gets. Work with the 12 hours, you’ll sleep more soundly, reflux will be less of an issue and you may be able to get away with a little more, if you eat it at the right time. 
What time do you generally eat dinner? Do you eat anything after? Do you intend to try the 12-hour rule? Maybe it's a good strategy post Memorial Day Weekend.

29 comments:

  1. Gina (Candid RD)May 30, 2012 at 4:08 AM

    Very interesting Lauren.  I mean the study about eating while we should be resting makes a lot of sense.  If someone is awake and eating when they should be asleep, clearly they aren't sleeping well and they will produce more ghrelin, right??
    As for the last and most recent study, I still think timing isn't as important as making sure you don't eat too many calories and that you choose the right types of calories.  I wonder how this would have turned out if the study were long term?  I'm very curious.  Also, I tell people it's fine not to eat past a certain time, but if you get hungry, your body needs the calories! Most of us eat at night not because we are hungry, but because we are bored or relaxed. That's the wrong reason to eat, and that will certainly promote weight gain.
    Great post Lauren!!  You always get me thinking.

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  2. Thanks Gina, yes long term would be great to see. I do think timing both in terms of distribution throughout the day and night eating really matters for both weight and health. As for hunger at night, if eating properly during the "8 hours" or daytime hours we shouldn't have a true hunger signal at 10pm. And yes, you're right re ghrelin, when sleep is curtailed we don't know if we're hungry or satisfied it all gets a little grey. 

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  3. Lisa (hartforwardcoaching)May 30, 2012 at 4:52 AM

    I'm going to try it.  At the very least I could do 10 hours.  9 - 7.  But I love the idea of giving our digestive systems an opportunity to rest!  Like other parts of our bodies it is overtaxed not only by what we eat but how much of it we can consume!  I'm in.  Great post.  Another tool in the weight loss/maintenance tool kit is always greatly appreciated! Thank you!  PS. I just posted the link to the on my Lisa Hart Coaching Facebook page (along with a recommendation that people subscribe and like your page! :) )

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  4. exactly Lisa "overtaxed" good work for it. Interestingly though that rest can make up for some overtaxing with calories. Yes, it's one tool. I hope people don't say- yes! I can eat more and just keep it to 8 hours a day. Thanks for repost we should like to you on our resources page let's discuss. 

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  5. I was discussing this with a friend this morning and I believe I already do this, but not as a rule. I want to pay attention to it, though. I eat breakfast and I like to do that pretty soon after waking. Supper is the same - I like it early. I'm probably regularly eating from about 6:30 am until 7:00 pm more or less. It's interesting to consider resting the body and giving the organs a chance to sit around so they can repair or whatever it is they need to do when I'm not making demands. 

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  6. This is really interesting.  When I'm trying to drop a few pounds, my usual go-to method is to make sure I don't eat anything after dinner, and it's usually pretty effective (I usually eat dinner around 7 or 7:30).  I wonder if this is more because the stuff I tend to eat after dinner is usually junk though.  Let's face it, I'm not snacking on celery at 9PM.  There's no way I could fit all my eating into 8 hours, and 12 would be a stretch, but 13 is doable - breakfast really has to be at 7 or so, right when I wake up, and I can sometimes eat dinner before 7 but during the week that's difficult.  It's a good thing to be mindful of though.  I wonder if your digestive system is less efficient at night when your body is slowing down preparing to sleep?

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  7. "let's face it, I'm not snacking on celery at 9pm" understood. I think there are two factors. First, cutting late night eating for some means cutting sugary or salty snacks. Second, it's unclear if it's that there are certain specific hours we shouldn't eat OR if it's just that we need a number of food-free hours. Mechanism and specifics unclear but eating from time we wake up to the time we go to sleep makes for unhealthy mice and people.

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  8. Exactly Caron, like most parts of our bodies, our digestive hormones can't constantly be firing. I love an early dinner too, I don't care if that makes me seem like an 8 or 80 year old.

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  9. I am a strong believer of intermittent fasting. I do 12 hours at night like you described and a little longer during the week end by having a very late breakfast or none at all. I don't know how it works but I do know my body likes it. I gained muscles and lost a bit of tummy fat (I don't have much to loose) lately without changing my workouts. I did stop eating all grains too, not just gluten grains. I suspect that it has to do with blood glucose, because I used to feel light headed when skipping a meal and that does not happen anymore. I just feel hungry but still full of energy, which is a nice forgotten feeling.

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  10. "my body likes it" that's what this is all about finding out what our body responds positively too. 

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  11. I read that study and in fact have been reading up on IF (Intermittent Fasting) and found it to be quite curious!  I couldn't conceive that going 12-16 hours without food would be good for the metabolism having been a slave to the "eat small meals every three hours" thinking.  But it makes sense, even just if it's the difference of a couple hundred unnecessary "bedtime snack" calories. 

    Nightime noshing has always been a challenge for me as I am an emotional/compulsive/boredom based snacker.  

    Since I know IF would not be good for me mentally (past ED) I have been trying to go 12 hours without food from dinner (or last meal) to breakfast (or first meal) and am rather quite liking it.  I always used to feel so stressed to eat within an hour of waking and now I am more relaxed.  It's nice.  I would like to be able to do the one day a week (20 hr) thing but I know that would just set me up for a binge.  Gotta do what works for you.  

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  12. Hi Cameo! You nailed an important tidbit, we are not mice. I don't mean to be sarcastic (actually sort of do) but if a certain # of hours pushes bad buttons, we have to back off. The key is that eating isn't a total revolving door and that small/frequent isn't too, too frequent. 

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  13. Interesting post, Lauren. So many conflicting studies...it's hard to decide what's best...I suppose time will tell. Thank you for sharing. 

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  14. I usually eat dinner around 7:30. Sometimes I have the after dinner munchies though in which case I rap it up about 9:30. I eat breakfast at 7:30 so I make it nearly 12 hours.

    I'm about to do 15+ hours food free as Ramadan slowly creeps back around. Scary how that happens. 

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  15. funny Ameena I thought of Ramadan when reviewing this study. We know about you and the TV munching. Maybe it's just the NYC real estate...

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  16. We have to be careful to evaluate new research and not write off as "too much conflicting" which I think makes people tune out. Nothing conflicting here really.

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  17. Lauren, I love how you sum it up: "the nutrition content of our food generally decreases the later it gets".

    That is the bog confounder in the human studies on free-living people: midnight snack rarely consist of broccoli. 

    I've seen people achieve quite a lot of weight and habit change by just sticking to "no food after dinner".

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  18. However, whether it's the lateness or the empty calories if we do as you say and close the kitchen with dinner we've killed 2 potential weight gain birds with one behavior change. Interesting with the Salk study that timing alone produced such different results and almost trumped nutrition content. 

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  19. Interesting!  It's totally not what I want to hear, especially since I'm bad about weekend nighttime munchies, but sometimes the truth hurts. 

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  20. Oh didn't mean to "hurt'". Still good to have the truth even if you only apply on weekdays. At least we know...

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  21. I tried to leave breakfast as late as possible... 9 or 10 at the weekends. 7am during the week.  When I am exercising, I leave eating dinner until late and then have a lighter meal so that I have no desire to snack. I do this by exercising around 6pm... it takes me an hour to cool down and get hungry..   I find my best days are when I only eat within a12 hour window.

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  22. I love the idea of a 12-hour fast and giving your digestive system that time to rest - and what a great habit to start for the month of June. Love how tangible your tips are, L! 

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  23. Thanks Erica, I love when common sense is backed up by research. A great summer goal.

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  24. Hi Bzybee, you certainly know a thing or two about weight loss. I don't know if I love pushing dinner too, too late just to avoid snacking but if you get to 12 hours, it can work.

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  25. Interesting study and makes sense to me. I tend to eat like this most nights, although on occasion I will get a little hungry around 9 or 10 if I have eaten an earlier dinner that evening. I am also interested in the research on intermittent fasting. I believe there was a recent study (on mice) suggesting fasting (or 500 or less calories/day) was protective against Alzheimer's and Parkinson's disease. I suspect we will be seeing a lot more research in this area in the future!

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  26. I generally go without eating from 12 - 14 hours , from night to morning.  Either I eat dinner early and then wake hungry enough for breakfast, or if I eat a large dinner late, or have too much dessert or late snacks, I'm not hungry for breakfast until a bit later on.  That generally works for me.  I feel like it gives my body time to do its business before I feed it again.

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  27. I'll go 12 hours without eating.  But only if I don't go to bed too late.  If I go to bed really late, I get hungry, and then I can't sleep.

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  28. hi to all..this really useful
    http://howtoloseweightfastf.com/

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  29. Fat is a political issueJune 1, 2014 at 9:51 AM

    The 12 hour rule works for me. The 'you must eat within an hour of waking 'definitely doesn't. I've been thin all my life and only now am I putting on weight in my fifties. (I look late Thirties). I am 5 feet 6 inches and struggling with belly fat from T'he Change'. The only thing that works well (for me) is the 12 hour rule and if I can, a bit of exercise after my morning tea BEFORE breakfast. Exercise really helps but it's chore. To stay slim I aim for a minimum 10 minutes a day but when I don't the fat comes back. Eat sensibly, (i.e. food that looks like it did when God made it) , occasional treats and fatty processed food are ok (you have to be happy) plus exercise you enjoy if you can bare it, plus the 12 hour rule, should be enough. Oh - and cut down on portion sizes. Also, for me religion and being politically minded helps. I refuse to line the pockets of super rich companies who feed us junk food. Good Luck everyone!

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