# Fasting - can a Fat person live significantly longer than a thin person? **URL:** \ **Category:** Factual Questions\ **Created:** [May 3, 2016, 10:06pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810 "2016-05-03T22:06:37Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![aceplace57](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aceplace57/32/3500_2.png) [@aceplace57](https://boards.straightdope.com/u/aceplace57)\ **Post date:** [May 3, 2016, 10:06pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/1 "2016-05-03T22:06:37Z")
I’ve often heard that fat gets stored to help humans survive periods with little or no food. Food supplies were uncertain in ancient times. A village’s failed crop meant starving throughout a long winter. Has obesity and survival during famine been studied or proven? Assume 600 calories a day – Would a 300 lb man outlive a 190 lb man? How about Fasting with only water?. ---
**Author:** ![Horatius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/horatius/32/3572_2.png) [@Horatius](https://boards.straightdope.com/u/Horatius)\ **Post date:** [May 3, 2016, 11:58pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/2 "2016-05-03T23:58:53Z")
I think a lot of it would depend on whether or not your 600 calories supply enough things like vitamins and minerals such that vital metabolic processes don’t get corrupted. It’s commonly thought that imbalances in such nutrients can kill you from things like heart failure long before you’ve lost all the excess weight you are carrying. > [@](#): > > Experts have since tried to pinpoint the dangers of crash diets (technically known as “very low calorie” diets). Shortages of potassium, magnesium, and copper have been suggested as possible causes of the arrhythmias seen in crash dieters, and studies have also found that the diets can cause a drop in blood pressure and sodium depletion. > **[How crash diets harm your health - CNN.com](https://www.cnn.com/2010/HEALTH/04/20/crash.diets.harm.health/)** > > Linda Bacon, Ph.D, dreads swimsuit season, but not because she has anything against the beach. > [@](#): > > More importantly, deaths associated with other specialized diets have been reported. In the 1960s and 1970s, liquid protein diets were associated with several deaths.[10] Some of these deaths were related to QT prolongation with pathologic findings of myocardial atrophy and myocarditis. Other findings in patients who had sudden cardiac death related to liquid protein diets included electrolyte disturbances such as hypokalemia, hypocalcemia, and hypomagnesemia.[10] Restriction of caloric intake to less than the basal needs results in the catabolism of protein and glycogen stores, which have a high water content, leading to a diuretic effect with the loss of free water and electrolytes. Ketone bodies undergo urinary excretion with a cation to maintain electrical neutrality, resulting in the additional loss of cations, including calcium, magnesium, and potassium.[11] When compounded by inadequate intake, deficiencies of these cations may ensue. Caloric restriction is not generally recommended on most low carbohydrate diets, including the Atkins diet, further emphasizing the dangers of using these diets without strict adherence to their recommendations. > **[Sudden Cardiac Death of an Adolescent During Dieting - Page 3](https://www.medscape.com/s/viewarticle/442894_3)** ---
**Author:** ![Ambivalid](https://avatars.discourse-cdn.com/v4/letter/a/a5b964/32.png) [@Ambivalid](https://boards.straightdope.com/u/Ambivalid)\ **Post date:** [May 4, 2016, 12:07am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/3 "2016-05-04T00:07:09Z")
VLC diets can be medically prescribed and monitored. However, only obese people qualify for such a diet. This suggests the answer to your question is yes, fat people would live longer. ---
**Author:** ![CCitizen](https://avatars.discourse-cdn.com/v4/letter/c/4af34b/32.png) [@CCitizen](https://boards.straightdope.com/u/CCitizen)\ **Post date:** [May 4, 2016, 12:11am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/4 "2016-05-04T00:11:00Z")
> [@aceplace57](#): > > Assume 600 calories a day – Would **a 300 lb man** outlive a 190 lb man? > > How about Fasting with only water?. Why are you picking on me? The idea is scary – I like tons of food. ---
**Author:** ![aceplace57](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aceplace57/32/3500_2.png) [@aceplace57](https://boards.straightdope.com/u/aceplace57)\ **Post date:** [May 4, 2016, 12:25am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/5 "2016-05-04T00:25:31Z")
I recall Survivor cast mostly regular people the first season and one really one heavy guy. They all lost weight but not in an alarming way. The former heavy guy had a lot of loose skin but was fine otherwise. Season 2 they cast a bunch of fit and low body fat types. Many were athletic. It didn’t end well. The winner Tina Wesson, was nearly skeletal. The runner ups Colby Donaldson and Keith Famie looked very emaciated compared to the fit bodies they started with day 1. This was only after 42 days. I’ve always wondered if the only survivors from a winter famine would be the (formerly) obese members of the village. ---
**Author:** ![sweat209](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sweat209](https://boards.straightdope.com/u/sweat209)\ **Post date:** [May 4, 2016, 12:31am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/6 "2016-05-04T00:31:06Z")
> [@aceplace57](#): > > I’ve often heard that fat gets stored to help humans survive periods with little or no food. Food supplies were uncertain in ancient times. A village’s failed crop meant starving throughout a long winter. > > Has obesity and survival during famine been studied or proven? > > Assume 600 calories a day – Would a 300 lb man outlive a 190 lb man? > > How about Fasting with only water?. I thought the guinness book of world records you can go month with out food but only two or three days with out water. You body will start to eat away of the stored fat than the muscles. Are you planning on going some there with out food for long time? Probably by day or two you start to get really bad hunger pains may not be nice.:eek::eek: ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [May 4, 2016, 1:21am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/7 "2016-05-04T01:21:07Z")
> [@sweat209](#): > > Are you planning on going some there with out food for long time? Probably by day or two you start to get really bad hunger pains I’ve done a couple of 3-day fasts (water only) in the past year. It’s actually much less difficult than you might expect. You definitely crave food, but there is no physical pain associated with it. You feel a bit weak by the third day, but not debilitated. ---
**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 4, 2016, 1:54am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/8 "2016-05-04T01:54:29Z")
I will take it even farther. Take that 300 pound man and have him lose weight to get down to 190 pounds, then (adequate vitamins and minerals very low calorie fast plan) fast both him and someone who has been 190 all of his adult life. The previously obese person will lose less weight. [Timely article](http://www.nytimes.com/2016/05/02/health/biggest-loser-weight-loss.html?hpw&rref=health&action=click&pgtype=Homepage&module=well-region®ion=bottom-well&WT.nav=bottom-well&_r=0) discussing that using contestants from “The Biggest Loser” as illustrations. > [@](#): > > … It has to do with resting metabolism, which determines how many calories a person burns when at rest. When the show began, the contestants, though hugely overweight, had normal metabolisms for their size, meaning they were burning a normal number of calories for people of their weight. When it ended, their metabolisms had slowed radically and their bodies were not burning enough calories to maintain their thinner sizes. … Sean Algaier, 36, a pastor from Charlotte, N.C., feels cheated. He went from 444 pounds to 289 as a contestant on the show. Now his weight is up to 450 again, and he is burning 458 fewer calories a day than would be expected for a man his size. ---
**Author:** ![Roderick\_Femm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/roderick_femm/32/14875_2.png) [@Roderick\_Femm](https://boards.straightdope.com/u/Roderick_Femm)\ **Post date:** [May 4, 2016, 1:58am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/9 "2016-05-04T01:58:44Z")
I lived for 9 months on less than 700 calories per day (plus prescription liquid potassium), and lost 150 pounds (starting at 335). Although the program was supervised by a doctor and I had monthly blood tests, the only change in my nutrient intake during this period was to add a slow-metabolizing iron supplement about halfway through. So if I had started with the iron supplement, I wouldn’t have needed the doctor or the blood tests. Someone my height who started out weighing 190 pounds might have lost 60 or 70 pounds or more on the same regimen, which would have been pretty serious. He would have looked like a death camp survivor, if he in fact survived at all. So yes, I would have survived longer than the normal weight man. As for water only, the problem isn’t the lack of calories but the lack of critical nutrients such as potassium and iron and who knows what else. Without taking in protein, the muscles would waste much faster. So while it’s possible I would have survived longer, it wouldn’t have been by nearly as much. On preview, excellent point **DSeid**. All true as I can attest from experience. It is harder for a formerly-fat person to stay at their reduced weight than it is for a person who was always at that weight to stay at that weight. ---
**Author:** ![nightshadea](https://avatars.discourse-cdn.com/v4/letter/n/7ba0ec/32.png) [@nightshadea](https://boards.straightdope.com/u/nightshadea)\ **Post date:** [May 4, 2016, 2:21am UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/10 "2016-05-04T02:21:08Z")
watching naked and afraid always has me wondering about this since there out there for a month pretty much not eating sicne I need to lose about 50 pounds would it be possible just to go on those nutrition drinks? and what would happen if I ate normal food again… ---
**Author:** ![bibliophage](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bibliophage/32/7615_2.png) [@bibliophage](https://boards.straightdope.com/u/bibliophage)\ **Post date:** [May 4, 2016, 5:44pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/11 "2016-05-04T17:44:27Z")
Sometime in the late 1960s, a 456 lb. man survived a fast lasting a year and 17 days. His weight fell to 180 lb. and stayed below 200 for at least five years. He consumed only non-caloric beverages, vitamin and yeast supplements, and sometimes potassium and sodium supplements. Other people have died trying a regime like this, but I’ve never heard of a normal-weight person on such a strict fasting regimen living more than two to three months. [Features of a successful therapeutic fast of 382 days' duration | Postgraduate Medical Journal](http://pmj.bmj.com/content/49/569/203.full.pdf+html) ---
**Author:** ![Atamasama](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atamasama/32/12961_2.png) [@Atamasama](https://boards.straightdope.com/u/Atamasama)\ **Post date:** [May 4, 2016, 5:55pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/12 "2016-05-04T17:55:27Z")
Okay I can’t stand it anymore… My brain insists on reading the first word of the thread title as “farting”. Please tell me I’m not the only one. (Maybe I am.) ---
**Author:** ![MikeF](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@MikeF](https://boards.straightdope.com/u/MikeF)\ **Post date:** [May 4, 2016, 6:04pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/13 "2016-05-04T18:04:25Z")
I just read “Heart of the Sea” (excellent read, BTW - an amazing survival story) and it is mentioned that there is a theory that the reason some Pacific Islanders tend toward obesity if for just this reason. On long, open water exploration journeys starvation became a problem. Those that were overweight tended to survive longer and thus, more likely to pass on genes tied to weight gain when they arrived at some new island. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [May 4, 2016, 6:06pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/14 "2016-05-04T18:06:58Z")
> [@aceplace57](#): > > I’ve always wondered if the only survivors from a winter famine would be the (formerly) obese members of the village. That’s the speculation as to why it’s so extraordinarily easy for people to gain weight, and even harder to lose it once it’s there. Basically evolution shaped us to pack on fat and keep it as long as possible, which more or less implies that getting fat easily and losing it slowly was for some period of time, a set of traits that were selected for by our environment. > **[Thrifty gene hypothesis](https://en.wikipedia.org/wiki/Thrifty_gene_hypothesis)** > > The thrifty gene hypothesis, or Gianfranco's hypothesis\[citation needed\] is an attempt by geneticist James V. Neel to explain why certain populations and subpopulations in the modern day are prone to diabetes mellitus type 2. He proposed the hypothesis in 1962 to resolve a fundamental problem: diabetes is clearly a very harmful medical condition, yet it is quite common, and it was already evident to Neel that it likely had a strong genetic basis. The problem is to understand how disease with a l... ---
**Author:** ![Nefario](https://avatars.discourse-cdn.com/v4/letter/n/59ef9b/32.png) [@Nefario](https://boards.straightdope.com/u/Nefario)\ **Post date:** [May 4, 2016, 6:24pm UTC](https://boards.straightdope.com/t/fasting-can-a-fat-person-live-significantly-longer-than-a-thin-person/753810/15 "2016-05-04T18:24:36Z")
[This guy](http://www.nytimes.com/1995/05/31/us/trapped-in-snow-in-oregon-salesman-died-after-9-weeks.html) (of normal weight) lasted 9 weeks with only water from snow and wrote a diary about most of it. I read a more detailed article once where part of his account describes his deterioration and he wrote “I can’t believe I’m in this bad of shape and still alive.” He didn’t survive - The story would be worth some searching if aceplace57 is seriously interested.