# Eating one large meal a day -- is it unhealthy? **URL:** \ **Category:** Factual Questions\ **Created:** [May 13, 2016, 4:43pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693 "2016-05-13T16:43:29Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Anny\_Middon](https://avatars.discourse-cdn.com/v4/letter/a/bc79bd/32.png) [@Anny\_Middon](https://boards.straightdope.com/u/Anny_Middon)\ **Post date:** [May 13, 2016, 4:43pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/1 "2016-05-13T16:43:29Z")
I have a nephew who has OCD. His therapist told my sister that it was the most severe case of OCD she ever treated. At any rate, he is working on it and has made some progress, but (as I think is fairly common with this disorder) this progress has been slow. One way his condition has manifested itself over the past couple of years is that he now eats one enormous meal a day. He has apparently put on considerable weight (I haven’t seen him in a few years; he lives in a different part of the country), but this may be more due to the fact that his typical meal is fast food. My brother-in-law (nephew’s stepfather) is convinced and has convinced my sister that nephew’s eating this way is extremely unhealthy. Whenever my nephew (who is 38 yo, BTW) visits them, he makes a point of telling nephew this. Nephew’s relationship with BIL is not that great, due at least in part to the fact that BIL is in general an asshole. Let’s ignore the fact that telling nephew his eating is unhealthy is unlikely in the extreme to have an effect. Face it, the percentage of cases in which someone has changed his eating habits due to being told, even by someone like a doctor who is in a position to judge, that his eating is unhealthy has got to be pretty small. But what’s the straight dope on how unhealthy this actually is? I remember reading some years ago that people are more likely to lose weight (or will lose more weight) if they eat several small meals a day rather than fewer large ones, even if the total number of calories consumed is the same. Thus someone who routinely eats six 250-calorie meals a day will lose weight faster than someone who eats two 750-calorie meals. But IIRC the effect was fairly small. I would guess this generalizes to mean that someone who eats one 3000-calorie meal will put on weight faster than someone who eats six 500-calorie meals, but that the amount of additional weight is probably small. Is this true? In what other ways, if any, is it unhealthy to eat just one big meal a day? I’m seeing asshole BIL at another nephew’s wedding soon, and if it comes up I’d like to have the straight dope. Just as I was composing this it occurred to me that the practice of one large meal might have been fairly common in prehistoric times. OK, maybe folks then were able to assuage some hunger with plant-based foods, but when the hunters came in with a boar, didn’t everyone essentially gorge? ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [May 13, 2016, 5:04pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/2 "2016-05-13T17:04:06Z")
I don’t know about losing weight, but I think it all plays into it. IIRC, eating smaller meals, more often, has to do with keeping your blood sugar a bit more stable throughout the day instead of it spiking once or twice every 24 hours. ---
**Author:** ![Pantastic](https://avatars.discourse-cdn.com/v4/letter/p/3bc359/32.png) [@Pantastic](https://boards.straightdope.com/u/Pantastic)\ **Post date:** [May 13, 2016, 5:12pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/3 "2016-05-13T17:12:40Z")
One big meal a day is a pattern that is likely to make the risk of diabetes a lot higher. It forces your body into a big blood sugar spike after the meal, then a big drop and low levels for the rest of the day. (IIRC this won’t make you diabetic if you’re not predisposed to it, but will take you from pre-diabetes into diabetes pretty quickly). It also means that your energy levels will generally be lower, which means less exercise, which means health issues. I wouldn’t be surprised if the weight gain is in part because he needs to eat more to have it ‘last all day’. > [@](#): > > Just as I was composing this it occurred to me that the practice of one large meal might have been fairly common in prehistoric times. OK, maybe folks then were able to assuage some hunger with plant-based foods, but when the hunters came in with a boar, didn’t everyone essentially gorge? Food preservation dates back a long time, and people who had never seen a fridge were unlikely to worry too much about eating cooked meat that was a day or two old. AFAIK there is no particular reason to think that people in those times were at all hesitant about spreading out their eating of meat. Also, protein takes a long time for the body to digest, it’s the carbs that really cause the blood sugar spiking that causes problems. Hunter gatherers generally didn’t have a lot of refined sugar, white bread, and french fries handy, while the fast food your cousin is eating likely has a ton of carbs. They were also much, much more active than people today, especially people with isolating mental issues. ---
**Author:** ![spamforbrains](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@spamforbrains](https://boards.straightdope.com/u/spamforbrains)\ **Post date:** [May 13, 2016, 6:33pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/4 "2016-05-13T18:33:14Z")
um, actually, it may be more healthy to eat one meal a day than to eat multiple small meals. After the invention of the idea of eating constantly, the obesity and diabetic epidemic exploded. It seems to be really good for your body to only eat occasionally. Insulin resistance, the cause of type II diabetes, seems to be caused by eating constantly. here’s one review > **[Fasting therapy for treating and preventing disease - current state of...](https://pubmed.ncbi.nlm.nih.gov/24434759/)** > > Periods of deliberate fasting with restriction of solid food intake are practiced worldwide, mostly based on traditional, cultural or religious reasons. There is large empirical and observational evidence that medically supervised modified fasting... ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [May 13, 2016, 6:56pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/5 "2016-05-13T18:56:48Z")
> [@spamforbrains](#): > > um, actually, it may be more healthy to eat one meal a day than to eat multiple small meals. After the invention of the idea of eating constantly, the obesity and diabetic epidemic exploded. um, actually there’s a difference between eating multiple small meals (equaling the same amount as your normal 3 or 2 meals) and “eating constantly”. I think people that ‘eat constantly’ are the ones that tend to put on weight since they really don’t know how much they eat. My dad is a ‘grazer’. He’ll get home from work and not be hungry for dinner and claim that he had ‘nothing to eat all day’. True, he skipped lunch and never had breakfast, but throughout the day he had three bowls of soup, a couple of handfuls of cookies, some mixed nuts that were laying out, a candy bar, 3 or 4 sodas etc. All things they he just sort of grabbed because he saw them, but he never ‘sat down and ate’, so to speak. 40+ years of this adds up. ---
**Author:** ![Pantastic](https://avatars.discourse-cdn.com/v4/letter/p/3bc359/32.png) [@Pantastic](https://boards.straightdope.com/u/Pantastic)\ **Post date:** [May 13, 2016, 7:06pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/6 "2016-05-13T19:06:52Z")
> [@spamforbrains](#): > > um, actually, it may be more healthy to eat one meal a day than to eat multiple small meals. After the invention of the idea of eating constantly, the obesity and diabetic epidemic exploded. > It seems to be really good for your body to only eat occasionally. Insulin resistance, the cause of type II diabetes, seems to be caused by eating constantly. > here’s one review > [Fasting therapy for treating and preventing disease - current state of evidence - PubMed](http://www.ncbi.nlm.nih.gov/pubmed/24434759) Multiple small meals and ‘eating constantly’ are two distinct things, most people who advocate multiple small meals advocate _healthy_ small meals while ‘eating constantly’ is often eating things like potato chips. The invention of the idea of eating constantly probably goes back to the first person who had a surplus of food, I’d like to see a cite for any historical ‘invention date’. Your article doesn’t support what you’re saying either, it talks about using semi-starvation diets to treat specific conditions, which is not eating constantly, multiple small meals, or a single large meal as an eating pattern. Instead, it’s advocating one medium meal per day with little else, and only doing it for short time periods instead of an eating pattern. ---
**Author:** ![iljitsch](https://avatars.discourse-cdn.com/v4/letter/i/77aa72/32.png) [@iljitsch](https://boards.straightdope.com/u/iljitsch)\ **Post date:** [May 13, 2016, 9:32pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/7 "2016-05-13T21:32:03Z")
I don’t think it’s inherently bad to eat just once a day. Our stomachs are big enough and everything else can also handle one large influx of nutrients every day rather than several small ones. Ignore all the diabetes and blood sugar talk, if we’re talking real food here it’s going to take many hours to digest so blood sugar spikes don’t really happen, even if we assume those are harmful to healthy people, which is questionable. Remember, humans aren’t built to have a 4-hour battery life. But… It’s hard enough to judge when you’ve had enough when eating a relatively small meal that has to last you a few hours. How are you going to know you’ve had enough for the next 24 hours? Answer: you don’t. So you’ll end up either gaining or losing weight or you’ll have to manage portions (I guess portion, singular) extremely carefully. ---
**Author:** ![spamforbrains](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@spamforbrains](https://boards.straightdope.com/u/spamforbrains)\ **Post date:** [May 14, 2016, 1:28am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/8 "2016-05-14T01:28:40Z")
In regards to diabetes, eating multiple small meals keeps your insulin levels high at all times. This causes your tissues to stop listening and then you develop insulin resistance, which is the cause of type II diabetes. It’s pretty clear people didn’t eat on a regular schedule until recently. Skipping meals and fasting have been shown to be highly effective methods to induce weight loss. I don’t know of any actual studies showing that snacking all day is an effective way to induce weight loss. Here’s one review [Intermittent energy restriction and weight loss: a systematic review - PubMed](http://www.ncbi.nlm.nih.gov/pubmed/26603882) ---
**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:** [May 14, 2016, 1:40am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/9 "2016-05-14T01:40:21Z")
I have no strong opinion on the matter but **spam** is right that there is at least [some support](http://www.scientificamerican.com/article/how-intermittent-fasting-might-help-you-live-longer-healthier-life/)for the pattern as healthier not riskier. > [@SciAm Jan 2013](#): > > Mattson and other researchers have championed the idea that intermittent fasting probably lowers the risks of degenerative brain diseases in later life. Mattson and his colleagues have shown that periodic fasting protects neurons against various kinds of damaging stress, at least in rodents. One of his earliest studies revealed that alternate-day feeding made the rats’ brains resistant to toxins that induce cellular damage akin to the kind cells endure as they age. In follow-up rodent studies, his group found that intermittent fasting protects against stroke damage, suppresses motor deficits in a mouse model of Parkinson’s disease and slows cognitive decline in mice genetically engineered to mimic the symptoms of Alzheimer’s. A decidedly slender man, Mattson has long skipped breakfast and lunch except on weekends. “It makes me more productive,” he says. The 55-year-old researcher, who has a Ph.D. in biology but not a medical degree, has written or co-authored more than 700 articles. > Mattson thinks that intermittent fasting acts in part as a form of mild stress that continually revs up cellular defenses against molecular damage. For instance, occasional fasting increases the levels of “chaperone proteins,” which prevent the incorrect assembly of other molecules in the cell. Additionally, fasting mice have higher levels of brain-derived neurotrophic factor (BDNF), a protein that prevents stressed neurons from dying. Low levels of BDNF have been linked to everything from depression to Alzheimer’s, although it is still unclear whether these findings reflect cause and effect. Fasting also ramps up autophagy, a kind of garbage-disposal system in cells that gets rid of damaged molecules, including ones that have been previously tied to Alzheimer’s, Parkinson’s and other neurological diseases. > One of intermittent fasting’s main effects seems to be increasing the body’s responsiveness to insulin, the hormone that regulates blood sugar. Decreased sensitivity to insulin often accompanies obesity and has been linked to diabetes and heart failure; long-lived animals and people tend to have unusually low insulin, presumably because their cells are more sensitive to the hormone and therefore need less of it. A recent study at the Salk Institute for Biological Studies in La Jolla, Calif., showed that mice that feasted on fatty foods for eight hours a day and subsequently fasted for the rest of each day did not become obese or show dangerously high insulin levels. > The idea that periodic fasting may offer some of the same health benefits as continuous calorie restriction—and allows for some feasting while slimming down—has convinced an increasing number of people to try it, says Steve Mount, a University of Maryland genetics professor who has moderated a Yahoo discussion group on intermittent fasting for more than seven years. Intermittent fasting “isn’t a panacea—it’s always hard to lose weight,” adds Mount, who has fasted three days a week since 2004. “But the theory [that it activates the same signaling pathways in cells as calorie restriction] makes sense.” … > > … from an evolutionary perspective, three meals a day is a strange modern invention. Volatility in our ancient ancestors’ food supplies most likely brought on frequent fasting—not to mention malnutrition and starvation. Yet Mattson believes that such evolutionary pressures selected for genes that strengthened brain areas involved in learning and memory, which increased the odds of finding food and surviving. If he is right, intermittent fasting may be both a smart and smartening way to live. Data not very convincing of benefit despite its current trendiness but evidence of harm is seriously lacking. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [May 14, 2016, 2:36am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/10 "2016-05-14T02:36:20Z")
One thing to keep in mind is that we evolved from animals that did not eat according to a regular schedule. If Grog the cave man (or more accurately Al the Australopithicus) had a bad day hunting, he didn’t eat that day. To be fair, our digestive systems have evolved a bit from the days of Al the Australopithicus. Our intestinal tracts are a bit smaller compared to our body size than those of our ape cousins. This comes from tens of thousands of years of preparing our food and making it easier to eat. What we’ve lost a bit of is the ability to eat difficult foods like seeds with thicker shells on them. Even so, we can survive just fine eating every other day. Some people do it. If we can skip entire days and it is no biggie, surely we can skip a few meals. Zoos have found that their animals are often healthier and live longer if they aren’t fed according to regular daily schedules, as this more closely resembles how those animals eat in the wild. Animals that are fed regularly, especially in confined zoo spaces, tend to end up overweight. Those of us who also live in confined spaces all day long (aka work cubicles) could probably learn a thing or two from this. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [May 14, 2016, 7:43am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/11 "2016-05-14T07:43:23Z")
> [@Anny\_Middon](#): > > … he now eats one enormous meal a day. He has apparently put on considerable weight Those 2 are related. Not eating all day makes your body quite hungry. And the body signal that “I’m full” lags behind, so at that one meal you eat an enormous amount, more calories than you would have eaten in 3 regular meals that day. And eating fast food just makes it worse. Many of the large meals contain more than a meals’ worth of the daily nutritional requirements, especially sodium (salt). And that encourages you to drink more of the sugary soda with it. ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [May 14, 2016, 8:26pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/12 "2016-05-14T20:26:20Z")
I have a t-shirt that reads, “I have CDO. It’s like OCD, except the letters are in alphabetical order, as they should be.” ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [May 14, 2016, 10:29pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/13 "2016-05-14T22:29:32Z")
> [@Joey\_P](#): > > um, actually there’s a difference between eating multiple small meals (equaling the same amount as your normal 3 or 2 meals) and “eating constantly”. > > I think people that ‘eat constantly’ are the ones that tend to put on weight since they really don’t know how much they eat. My dad is a ‘grazer’. He’ll get home from work and not be hungry for dinner and claim that he had ‘nothing to eat all day’. True, he skipped lunch and never had breakfast, but throughout the day he had three bowls of soup, a couple of handfuls of cookies, some mixed nuts that were laying out, a candy bar, 3 or 4 sodas etc. All things they he just sort of grabbed because he saw them, but he never ‘sat down and ate’, so to speak. 40+ years of this adds up. Where does your dad work, that he can eat three bowls of soup during the day and then claim he skipped lunch? ---
**Author:** ![Flyer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/flyer/32/7298_2.png) [@Flyer](https://boards.straightdope.com/u/Flyer)\ **Post date:** [May 15, 2016, 12:02am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/14 "2016-05-15T00:02:27Z")
> [@spamforbrains](#): > > In regards to diabetes, eating multiple small meals keeps your insulin levels high at all times. This causes your tissues to stop listening and then you develop insulin resistance, which is the cause of type II diabetes. > It’s pretty clear people didn’t eat on a regular schedule until recently. Skipping meals and fasting have been shown to be highly effective methods to induce weight loss. I don’t know of any actual studies showing that snacking all day is an effective way to induce weight loss. > Here’s one review [Intermittent energy restriction and weight loss: a systematic review - PubMed](http://www.ncbi.nlm.nih.gov/pubmed/26603882) Personally speaking, I would be pretty leery of fasting for more than a day or so. It’s well documented that calorie deprivation reduces the metabolism rate, so that when you start eating again, it takes a smaller number of calories to gain weight. ---
**Author:** ![spamforbrains](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@spamforbrains](https://boards.straightdope.com/u/spamforbrains)\ **Post date:** [May 15, 2016, 3:02am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/15 "2016-05-15T03:02:54Z")
> [@](#): > > It’s well documented that calorie deprivation reduces the metabolism rate, so that when you start eating again, it takes a smaller number of calories to gain weight. Most of the intermittent fasters either skip a meal or two per day several times a week or they fast two days a week (spread out, not back-to-back) they don’t engage in prolonged fasting. There’s some other studies showing that fasting briefly, aka skipping breakfast or not-eating for one day does not result in people eating massively increased amounts of food at the next meal. It seems to be a very effective way to both reduce overall calorie intake and reduce the risk of type II diabetes by restoring insulin sensitivity. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [May 15, 2016, 7:38pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/16 "2016-05-15T19:38:45Z")
Speaking for myself I really started losing weight (and have kept it off for 5 years) by simply stopping eating between meals while keeping the meals fairly modest. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [May 17, 2016, 12:14am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/17 "2016-05-17T00:14:35Z")
It was my understanding that intermittent fasting was being show to be good for you. > **[10 Health Benefits of Intermittent Fasting](https://www.healthline.com/nutrition/10-health-benefits-of-intermittent-fasting)** > > Discover a variety of evidence-based benefits of intermittent fasting, from weight loss to reduced risk of diabetes to better heart health. ---
**Author:** ![Ambivalid](https://avatars.discourse-cdn.com/v4/letter/a/a5b964/32.png) [@Ambivalid](https://boards.straightdope.com/u/Ambivalid)\ **Post date:** [May 17, 2016, 1:00am UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/18 "2016-05-17T01:00:30Z")
> [@spamforbrains](#): > > In regards to diabetes, eating multiple small meals keeps your insulin levels high at all times. This causes your tissues to stop listening and then you develop insulin resistance, which is the cause of type II diabetes. Cite? I just read a study from 2015 that pretty much says the opposite. One thing eating only once a day increases is binge-eating tendencies. ETA: [http://health.usnews.com/health-news/health-wellness/articles/2015/06/16/intermittent-fasting-vs-6-small-meals-a-day-whats-best-for-weight-loss](http://health.usnews.com/health-news/health-wellness/articles/2015/06/16/intermittent-fasting-vs-6-small-meals-a-day-whats-best-for-weight-loss) ---
**Author:** ![SpeedwayRyan](https://avatars.discourse-cdn.com/v4/letter/s/ce7236/32.png) [@SpeedwayRyan](https://boards.straightdope.com/u/SpeedwayRyan)\ **Post date:** [May 17, 2016, 12:31pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/19 "2016-05-17T12:31:59Z")
> [@Joey\_P](#): > > My dad is a ‘grazer’. He’ll get home from work and not be hungry for dinner and claim that he had ‘nothing to eat all day’. True, he skipped lunch and never had breakfast, but throughout the day he had three bowls of soup, a couple of handfuls of cookies, some mixed nuts that were laying out, a candy bar, 3 or 4 sodas etc. This all makes perfect sense to me…except the fact that your dad sneaks in three bowls of soup. Like he’s just walking along and a steaming hot bowl of soup is lying there and it doesn’t belong to anyone, so he might as well casually eat it. And then that happens two more times in a day. And then he claims he didn’t eat. 😉 ---
**Author:** ![Pantastic](https://avatars.discourse-cdn.com/v4/letter/p/3bc359/32.png) [@Pantastic](https://boards.straightdope.com/u/Pantastic)\ **Post date:** [May 17, 2016, 1:15pm UTC](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693/20 "2016-05-17T13:15:24Z")
> [@spamforbrains](#): > > In regards to diabetes, eating multiple small meals keeps your insulin levels high at all times. This causes your tissues to stop listening and then you develop insulin resistance, which is the cause of type II diabetes. Cite please. If you have one, I’ll send it to all of the doctors and professional diabetic counselors who told me the direct opposite - but I doubt you do. > [@](#): > > I don’t know of any actual studies showing that snacking all day is an effective way to induce weight loss. I don’t know of any actual posters claiming that snacking all day is an effective way to induce weight loss. [Next page](https://boards.straightdope.com/t/eating-one-large-meal-a-day-is-it-unhealthy/754693.md?page=2)