# Fresh fruit is...bad for you??? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [July 16, 2004, 11:02pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504 "2004-07-16T23:02:45Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [July 16, 2004, 11:02pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/1 "2004-07-16T23:02:45Z")
My daughter is the cafeteria staff in a small preschool in Bakersfield. A while back I was talking to her about her job, and the difficulties of feeding kids that age. During uor conversation she told me that the authorities who decide such things have decided that fresh fruit servings should be curtailed and veggies proffered, even though the kiddies won’t eat them. Strict guidelines have been established, and the school follows them. Ok, I’m diabetic, and I realize that fruit does contain a _lot_ of sugar. I like fruit (mangoes. mmm) a lot and it’s dificult to limit myself. But as an alternative to candy, which is very often the case, does it make sense to pull the bananas? I know there are some nutrition experts on the SDMB. What say you all? Peace, mangeorge ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 16, 2004, 11:10pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/2 "2004-07-16T23:10:47Z")
Fruit contains Fructose, which has the same empirical formula as Glucose, but has a structure which does not allow it to be metabolized the same way. Fructose is metabolized in the liver and is preferentially converted into fat. Fructose also does not cause a signifigant rise in blood sugars and other appetite supressing hormones such as leptin. ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 16, 2004, 11:24pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/3 "2004-07-16T23:24:19Z")
I realize that the above doesn’t explain too much. I would imagine that research and current thinking tends to make peoplefeel it is better to get the vitamins and other micronutrients the body needs from vegetables that don’t contain fructose. What with rises in obesity in children, perhaps the nutritional feels it is important to find alternatives to foods that get stored as more fat. (and rises in LDL levels) ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [July 16, 2004, 11:39pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/4 "2004-07-16T23:39:37Z")
Really? then why are diabetics warned away from full servings of fruits and especially juices? Maybe I’d better re-check my guidelines. I _am_ one of those people who tend to exaggerate. “limit your mango intake” reads as “don’t eat mangoes”. 🙂 “My kingdom for a pancreas.” ---
**Author:** ![Terminus\_Est](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terminus_est/32/3087_2.png) [@Terminus\_Est](https://boards.straightdope.com/u/Terminus_Est)\ **Post date:** [July 17, 2004, 1:44am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/5 "2004-07-17T01:44:57Z")
> [@Epimetheus](#): > > Fruit contains Fructose, which has the same empirical formula as Glucose, but has a structure which does not allow it to be metabolized the same way. Fructose is metabolized in the liver and is preferentially converted into fat. Fructose also does not cause a signifigant rise in blood sugars and other appetite supressing hormones such as leptin. Cite? ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [July 17, 2004, 2:22am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/6 "2004-07-17T02:22:25Z")
> [@Epimetheus](#): > > Fructose is metabolized in the liver and is preferentially converted into fat. Huh? Fructose is a handy substrate for the liver to convert to either glucose via gluconeogenesis, or to turn directly into glycogen! > [@](#): > > Plasma fructose may enter cells for glycolysis or gluconeogenesis by one of two pathways: > > in hepatocytes: > fructokinase converts fructose to fructose-1-phosphate > fructose-1-phosphate aldolase converts fructose-1-phosphate to dihydroacetone phosphate and glyceraldehyde > triose kinase converts glyceraldehyde to glyceraldehyde-3-phosphate > triose phosphate isomerase converts dihydroacetone phosphate to glyceraldehyde-3-phosphate > glyceraldehyde-3-phosphate then enters further glycolytic or gluconeogenic reactions according to the energy status of the hepatocyte > > in other cells, particularly adipocytes: > hexokinase converts fructose into fructose-6-phosphate; fructose competes with glucose for phosphorylation > fructose-6-phosphate enters glycolysis [http://www.gpnotebook.co.uk/cache/1798635578.htm](http://www.gpnotebook.co.uk/cache/1798635578.htm) ---
**Author:** ![MaryEFoo](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@MaryEFoo](https://boards.straightdope.com/u/MaryEFoo)\ **Post date:** [July 17, 2004, 2:39am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/7 "2004-07-17T02:39:57Z")
Well, fruit **juices** (apple juice, orange juice…) are a lot like thick sugar-water with some vitamins etc sprinkled in. Diabetics need to watch that kind of thing. IIR, apple juice might have the sugars of two apples, and hits the bloodstream fast. Chewing up one apple is more filling, provides more health factors, and doesn’t abruptly bump up the blood-sugar. Last I heard, eating fruit as fruit was better. So I don’t get it. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [July 17, 2004, 3:37am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/8 "2004-07-17T03:37:57Z")
> [@Qadgop the Mercotan](#): > > Huh? Fructose is a handy substrate for the liver to convert to either glucose via gluconeogenesis, or to turn directly into glycogen! > [http://www.gpnotebook.co.uk/cache/1798635578.htm](http://www.gpnotebook.co.uk/cache/1798635578.htm) C’mon, doc. 😕 😃 ---
**Author:** ![Typo\_Negative](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/typo_negative/32/484_2.png) [@Typo\_Negative](https://boards.straightdope.com/u/Typo_Negative)\ **Post date:** [July 17, 2004, 4:22am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/9 "2004-07-17T04:22:23Z")
I dunno, but I have had me some _serious_ glycemic responses from mangoes. Other fruits, not so much. ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [July 17, 2004, 5:01pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/10 "2004-07-17T17:01:54Z")
I’ve never heard the bit about fructose being preferentially converted to fat. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [July 17, 2004, 6:56pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/11 "2004-07-17T18:56:54Z")
There I go again! I checked the diabetes food chart again. What’s reccommended is 3-4 _servings_ of one medium fruit a day, not just one fruit. The good thing is that I rarely follow advice, so I have pretty much been eating the reccommended amount. Trouble is that it’s not as much fun when it’s not a sin. 😉 Oh well, off to the USDA site. The topic is child nutrition, not diabetes. ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 18, 2004, 2:52am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/12 "2004-07-18T02:52:15Z")
Cites: Same chemical formula: [http://home.howstuffworks.com/food2.htm](http://home.howstuffworks.com/food2.htm) > [@](#): > > Fructose has the same chemical formula as glucose (C6H12O6), but the atoms are arranged slightly differently. The liver converts fructose to glucose Fructose is preferentially converted into fat in the liver: [http://www.drkaslow.com/html/fructose.html](http://www.drkaslow.com/html/fructose.html) > [@](#): > > In another scientific article from the American Journal of Clinical Nutrition (Nov 2002;76(5):911-22), the metabolism of fructose was again discussed. The report indicated that fructose, compared with glucose, **is preferentially metabolized to fat in your liver**. I have more cites if you want em. Hey, I just report em as I read em. I have cites to other doctors saying the same thing too, so I dunno. ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 18, 2004, 2:55am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/13 "2004-07-18T02:55:33Z")
Here is a couple more cites: (how come when I ask for a cite in IMHO I get a bunch of crap, but you all can ask away? huh) [http://www.mercola.com/2002/jan/5/fructose.htm](http://www.mercola.com/2002/jan/5/fructose.htm) [http://www.mercola.com/2002/nov/13/fructose.htm](http://www.mercola.com/2002/nov/13/fructose.htm) [http://ific.org/publications/qa/fructoseqa.cfm](http://ific.org/publications/qa/fructoseqa.cfm) And even here: [http://www.touchtmj4.com/4whatson/lauriemeyer/meyer030904.asp](http://www.touchtmj4.com/4whatson/lauriemeyer/meyer030904.asp) > [@](#): > > Fructose is absorbed and metabolized differently than other sugars. It doesn’t stimulate insulin or leptin. Instead it is metabolized directly in the liver and forms the backbone of the triglyceride molecule, which is stored as body fat. In fact, fructose is more easily turned to fat than any other carbohydrate. Because it is directly metabolized in the liver and doesn’t contain any enzymes, it depletes many minerals while increasing cholesterol production. It stresses the body and it doesn’t shut off appetite, so you never feel full when eating. It seems particularly bad for diabetics and people with heart disease. A big reason it is causing so many problems is because we are consuming so much of it. In 1970 Americans ate ½ lb. of fructose, now we consume well over 60 lbs. each according to research published in the American Journal of Clinical Nutrition. Somehow I get the feeling these cites aren’t even going to get read though. That seems to be the trend. ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 18, 2004, 3:02am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/14 "2004-07-18T03:02:42Z")
Also from the IFIC- [http://ific.org/publications/qa/fructoseqa.cfm](http://ific.org/publications/qa/fructoseqa.cfm) > [@](#): > > Even though commonly consumed sugars provide basically the same number of calories, they are metabolized and used by the body in different ways. For instance, glucose from dietary sources is digested, absorbed, transported to the liver, and released into the general blood stream. Many tissues take up glucose from the blood to use for energy; this process requires insulin. **Fructose is predominantly metabolized in the liver, but unlike glucose it does not require insulin to be used by the body.** ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [July 18, 2004, 3:38am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/15 "2004-07-18T03:38:08Z")
**Epimetheus** , all those cites just say that it’s easier to make triglycerides out of fructose than out of glucose. That doesn’t mean the body turns fructose into fat rather than into glucose or glycogen. Just that when the body finds it necessary to turn sugar into fat precursors, it expends less energy doing so with fructose. Tho I see by reading your original post that you may not have been implying such in the first place, and I may have mistaken your point. I’m not sure if we’re arguing the same thing or not. My point, which I did not make too clearly, was that fructose, while having a better glycemic index than some other sugars, still ends up being metabolized pretty much like other sugars once in the cell, and thus isn’t that much better than other sources of carbs. Which is why I tell my patients to knock off the fruit juices, and just eat the fruit. One gets less fructose and more fiber and a few other nutrients by doing so. I’ve ranted against the practice of embracing juice as a “healthy” alternative to soda for kids and others in a number of threads here before. As for vegetables being better than fruit, maybe they are. But I’m a pragmatist. Just getting people to move from candy to fruit would be a true milestone of positive change. I wouldn’t expect in a million years to get people to give up apples, cherries, strawberries, etc. in preference for more broccoli, cauliflower and brussels sprouts. Are we on the same page now? I’m honestly not sure. thank you for your effort to clarify. ---
**Author:** ![Nametag](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nametag/32/406_2.png) [@Nametag](https://boards.straightdope.com/u/Nametag)\ **Post date:** [July 18, 2004, 4:33am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/16 "2004-07-18T04:33:33Z")
Fructose is metabolizd to glucose, and glucose raises insulin. Your cites contradict their own thesis (and each other). QtM has already covered the semantic nonsense underlying the fat claim, but I’ll second him. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [July 18, 2004, 5:05am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/17 "2004-07-18T05:05:04Z")
Got the straight dope. Here’s what the kiddies, in preschools in general, were _eating_; mac & cheese, bananas, and flavored (and sweetened) apple juice. Juice of choice being that stuff in the neat little boxes. Other stuff was offered, but largely not eaten. Many kids would fill up on bananas and “juice”. So they were advised to offer water, varied main dishes, and a variety of fruits and veggies. They hide brocoli on the pizza. They also have healthy hot dogs, and the kids love them. 😉 My daughter makes up fake “lunchables”. ---
**Author:** ![Green\_Bean](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/green_bean/32/1760_2.png) [@Green\_Bean](https://boards.straightdope.com/u/Green_Bean)\ **Post date:** [July 18, 2004, 5:20am UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/18 "2004-07-18T05:20:35Z")
Of course fruit is bad for you. Fruit contains… CARBS! :eek: :eek: :eek: ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 18, 2004, 1:08pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/19 "2004-07-18T13:08:56Z")
Nametag: My cites support what I **say** \*. They don’t contradict themselves. You just have to **read** them. I did not say that all fructose is converted into fat. I said it was **preferentially** metabolized into fat. They also say that fructose does not cause as **signifigant** a rise in insulin as glucose. My cites are from valid and from good sources (like the American Journal of clinical Nutrition). If you think they are in “error” perhaps you would care to provide cites of better authority? \*rather than what you think I am saying, no doubt. ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [July 18, 2004, 1:24pm UTC](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504/20 "2004-07-18T13:24:55Z")
> [@Qadgop the Mercotan](#): > > **Epimetheus** , all those cites just say that it’s easier to make triglycerides out of fructose than out of glucose. That doesn’t mean the body turns fructose into fat rather than into glucose or glycogen. Just that when the body finds it necessary to turn sugar into fat precursors, it expends less energy doing so with fructose. The cites say it is preferentially converted into triglycerides. Since the body itself is not a thinking being, I would assume it is predominately converted into fat because it is easier. Just as my cites claim, fructose is metabolized differently than glucose- in the liver. It is easier in this process to convert the fructose into fat. Some of this will no doubt be metabolized into glucose. Depending on the amount It is also more likely to replentish the livers glycogen stores than actually make it out into the blood stream as well. > [@](#): > > Tho I see by reading your original post that you may not have been implying such in the first place, and I may have mistaken your point. I’m not sure if we’re arguing the same thing or not. My point, which I did not make too clearly, was that fructose, while having a better glycemic index than some other sugars, still ends up being metabolized pretty much like other sugars once in the cell, and thus isn’t that much better than other sources of carbs. But only one sugar is metabolized in the cell, am I not correct? Glucose. All other carbohydrates are first broken down into glucose. I was taught that the only sugar that enters the Krebs cycle was glucose. > [@](#): > > Which is why I tell my patients to knock off the fruit juices, and just eat the fruit. One gets less fructose and more fiber and a few other nutrients by doing so. I’ve ranted against the practice of embracing juice as a “healthy” alternative to soda for kids and others in a number of threads here before. I agree, fruits juices are bad. I wouldn’t say that an apple or bannana is necessarily bad. The amount of fructose in natural fruilts is low. > [@](#): > > As for vegetables being better than fruit, maybe they are. But I’m a pragmatist. Just getting people to move from candy to fruit would be a true milestone of positive change. I wouldn’t expect in a million years to get people to give up apples, cherries, strawberries, etc. in preference for more broccoli, cauliflower and brussels sprouts. > > Are we on the same page now? I’m honestly not sure. > > thank you for your effort to clarify. I assume so. 😃 [Next page](https://boards.straightdope.com/t/fresh-fruit-is-bad-for-you/255504.md?page=2)