# Wait, the time we eat DOES matter in terms of health and weight gain/loss? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [April 23, 2014, 3:14pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775 "2014-04-23T15:14:10Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![Jackknifed\_Juggernaut](https://avatars.discourse-cdn.com/v4/letter/j/9de053/32.png) [@Jackknifed\_Juggernaut](https://boards.straightdope.com/u/Jackknifed_Juggernaut)\ **Post date:** [April 23, 2014, 3:14pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/1 "2014-04-23T15:14:10Z")
Based on many nutrition questions that have been asked on these boards, I learned that the time we eat our meals has no direct impact on health or weight gain or loss. If anything, it’s the unhealthy and high-calorie meals that we tend to eat later in the evening that are the culprit. But an excerpt in this article in the New Yorker says otherwise: > **[Why Do We Eat, and Why Do We Gain Weight?](https://www.newyorker.com/science/maria-konnikova/why-do-we-eat-and-why-do-we-gain-weight)** > > We eat because we want to eat; not because we need to. Can we transform the way we think about dieting? > [@](#): > > …If two groups consume the same number of calories but one group eats them during the first part of the day and the other during the second, the latter group is up to two times more likely to be obese. In one study, two groups of people were assigned to eat the same number of calories each day during a twelve-week period. One group received more of them during breakfast, and the other had more during dinner. The breakfast group lost significantly more weight. ---
**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\ **Post date:** [April 23, 2014, 3:23pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/2 "2014-04-23T15:23:14Z")
There could be indirect impacts that explain the results in the study. For instance, eating large high-calorie breakfasts could tend to increase metabolic rate during the day while people are active, thus burning more of the calories. ---
**Author:** ![FoieGrasIsEvil](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foiegrasisevil/32/16638_2.png) [@FoieGrasIsEvil](https://boards.straightdope.com/u/FoieGrasIsEvil)\ **Post date:** [April 23, 2014, 4:10pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/3 "2014-04-23T16:10:46Z")
How could time ever not matter? If you eat four slices of pizza at midnight and then go to bed, you’re not burning any of that off by sleeping and you are gaining fat. Or is that incorrect? ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [April 23, 2014, 4:53pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/4 "2014-04-23T16:53:45Z")
> [@FoieGrasIsEvil](#): > > How could time ever not matter? If you eat four slices of pizza at midnight and then go to bed, you’re not burning any of that off by sleeping and you are gaining fat. …to replace the fat you burned earlier in the day when you didn’t eat the pizza but still had activity. Assuming the simple “calories in vs. calories burned” model is accurate, the order and timing shouldn’t matter, just the total amounts over time. I’ve not seen the research study talked about above, but if timing _does_ matter, that would definitely be an interesting discovery. ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [April 23, 2014, 4:54pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/5 "2014-04-23T16:54:00Z")
> [@FoieGrasIsEvil](#): > > How could time ever not matter? If you eat four slices of pizza at midnight and then go to bed, you’re not burning any of that off by sleeping and you are gaining fat. > > Or is that incorrect? As opposed to eating them 4 hours before bed and, um, what? Sitting on the couch watching TV isn’t appreciably different than sleeping when it comes to burning calories. So I don’t think that’s a major factor. ---
**Author:** ![marshmallow](https://avatars.discourse-cdn.com/v4/letter/m/df705f/32.png) [@marshmallow](https://boards.straightdope.com/u/marshmallow)\ **Post date:** [April 23, 2014, 5:01pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/6 "2014-04-23T17:01:22Z")
If that’s true it seems like a big oversight in human metabolism. You’re a hunter gatherer on the edge of survival and you might live or die depending on the time of day you eat? ---
**Author:** ![FoieGrasIsEvil](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foiegrasisevil/32/16638_2.png) [@FoieGrasIsEvil](https://boards.straightdope.com/u/FoieGrasIsEvil)\ **Post date:** [April 23, 2014, 6:02pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/7 "2014-04-23T18:02:50Z")
Let’s say you don’t regularly exercise, and ate a normal dinner at a normal time (say…six?), but then you drank ten beers and THEN ate all that pizza at midnight? What about then? ---
**Author:** ![Jackknifed\_Juggernaut](https://avatars.discourse-cdn.com/v4/letter/j/9de053/32.png) [@Jackknifed\_Juggernaut](https://boards.straightdope.com/u/Jackknifed_Juggernaut)\ **Post date:** [April 23, 2014, 6:12pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/8 "2014-04-23T18:12:26Z")
> [@FoieGrasIsEvil](#): > > Let’s say you don’t regularly exercise, and ate a normal dinner at a normal time (say…six?), but then you drank ten beers and THEN ate all that pizza at midnight? What about then? It would be the same as if you had the beer, pizza and normal dinner all when you woke up at 6am and then didn’t eat/drink anything for the rest of the day. At least that’s how it’s supposed to work. The excerpt in the OP says otherwise, which is why it raised my eyebrows. ---
**Author:** ![jerez](https://avatars.discourse-cdn.com/v4/letter/j/c68b51/32.png) [@jerez](https://boards.straightdope.com/u/jerez)\ **Post date:** [April 23, 2014, 8:41pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/9 "2014-04-23T20:41:40Z")
Just as a matter of general health (as opposed to weight gain/loss), I think most people don’t sleep as well on a full stomach. ---
**Author:** ![Hockey\_Monkey](https://avatars.discourse-cdn.com/v4/letter/h/a183cd/32.png) [@Hockey\_Monkey](https://boards.straightdope.com/u/Hockey_Monkey)\ **Post date:** [April 23, 2014, 9:34pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/10 "2014-04-23T21:34:41Z")
My understanding: Eating breakfast wakes up your metabolism for the day. Skipping meals slows the metabolism. It’s not that eating right before bed is bad or will make you gain weight. It’s not eating first thing in the morning that hinders weight loss. ---
**Author:** ![FoieGrasIsEvil](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foiegrasisevil/32/16638_2.png) [@FoieGrasIsEvil](https://boards.straightdope.com/u/FoieGrasIsEvil)\ **Post date:** [April 23, 2014, 10:50pm UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/11 "2014-04-23T22:50:31Z")
What is the difference in terms of calories burned/metabolic rate while engaged in normal, quasi-sedentary after dinner/before bed activities versus sleeping? ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [April 24, 2014, 12:08am UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/12 "2014-04-24T00:08:52Z")
> [@FoieGrasIsEvil](#): > > What is the difference in terms of calories burned/metabolic rate while engaged in normal, quasi-sedentary after dinner/before bed activities versus sleeping? That’s pretty much the open question. Almost anything you read on the Internet about “metabolic rates” (or for that matter, nutrition in general) is bunk or wild speculation. The assumption has always been that the homeostasis rate (pretty much just keeping your body alive) dominated, and that calories were basically like a bank account: when you consumed or expended them didn’t matter much. The study lends some evidence to the idea that maybe the calorie usage rate (or more accurately, the calorie usage efficiency) does change over the day. I don’t know how much you can read into one study, though. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [April 24, 2014, 3:07am UTC](https://boards.straightdope.com/t/wait-the-time-we-eat-does-matter-in-terms-of-health-and-weight-gain-loss/686775/13 "2014-04-24T03:07:15Z")
The problem with how most people misuse the “calories in calories out” model is that they mistakenly presume that the “calorie out” side is not impacted by aspects of the “calories in” side. The reality is that we not are dealing with a car here. This machine reacts in more complex ways. [Here’s](http://onlinelibrary.wiley.com/doi/10.1038/oby.2009.264/full) a mouse study that documents the impact of timing of intake on weight gain. > [@](#): > > The present results show that simply modifying the time of feeding alone can greatly affect body weight. Mice fed a high-fat diet only during the “right” feeding time (i.e., during the dark) weigh significantly less than mice fed only during the time when feeding is normally reduced (i.e., during the light). … > > … In the past few years, there have been a number of genetic and environmental studies linking circadian clock and metabolic gene networks with one another. For example, a mutation of the circadian clock gene, Clock, can lead to obesity and the metabolic syndrome and alterations in the circadian expression of metabolic genes (4), while mice fed a high-fat diet show alterations in circadian behavior as well as the levels and timing of the expression of clock and metabolic genes in both central and peripheral tissues involved in energy regulation (5,8). In humans, phase delayed eating patterns of non-breakfast eaters or patients with night-eating syndrome, have suggested an association with increased BMI (6,7,13). Additionally, studies of patients with circadian:behavior misalignment develop indictors of the metabolic syndrome, specifically an increase in circulating glucose and insulin levels (10). These findings, taken together with the present results indicate that the synchrony between circadian and metabolic processes plays an important role in the regulation of energy balance and body weight control. Importantly, this study is the first to show causal evidence that feeding at the “wrong” time can lead to weight gain. > > The present results indicate that a better understanding of the role of the circadian system in weight regulation could have important implications for combating the obesity epidemic facing the human population today. Once gained, losing body weight by controlling energy intake through dieting and/or energy expenditure has proven to be difficult over a prolonged period of time, making significant and sustained weight loss challenging (14). A preventive strategy based on behavior modification (e.g., the timing of food intake), possibly without a significant change in caloric intake or physical activity, could be a critical element needed to slow the ever-increasing incidence of obesity and associated cardiometabolic disorders facing the world today. [Another study in mice](http://ac.els-cdn.com/S1550413112001891/1-s2.0-S1550413112001891-main.pdf?_tid=220b765e-cb5c-11e3-aa93-00000aab0f6c&acdnat=1398308412_4472ae2ff53409c45704750ead8477d0), this one demonstrating that restricting the same calories in a high fat diet to be eaten in an 8 hour window of their naturally active times versus ad lib over 24 hours led to less obesity and less metabolic resistance. It is a pretty damn impressive study. Eating during times of day that organisms are entrained to not be active during disrupts a host of metabolic pathways tied to circadian rhythms. [Here’s a blog post](http://blog.lluniversity.com/eating-more-earlier-in-the-day-may-benefit-weight-loss-and-maintenance/) that summarizes a few human studies. Interesting stuff.