Is Fructose More in Line with Fat Burning? page

[wiltondeportes]

I got to thinking recently. I know fructose goes directly to the liver where it is either transferred into glucose or stored as fat (my understanding is that this happens fairly quickly). Meanwhile, if you eat glucose, it goes to the muscles first and can be stored after that. I'm not sure how quickly it becomes fat, but I believe fructose is quicker.

I have been binging on fruit lately. 11 peaches on Sunday, a pound of plums yesterday...to no ill effects. I can to a possible conclusion that fructose works great for my metabolism because I burn fat, not glucose. I let all that fructose turn into fat, and then I quickly burn it off. I need SOME carbs in my diet one way or another too. If I ate glucose, I'd be reaching for sweet potatoes and other root vegetables.

Thoughts on fructose vs glucose as source for carbs and effect on our metabolisms?

[EricS]

The problem with fructose is it doesn't turn into JUST fat. There's a video that someone has posted in the past that's like an hour talking about just why sugar/fructose is so bad when compared to glucose. However it also talks about how in nature the only source of fructose comes with its own antidote in the form of fiber. Now that's not to say that binging on fruit is a just fine, but it is a whole lot better than juice or soda.

[Ummmmya]

The problem with fructose is it doesn't turn into JUST fat. There's a video that someone has posted in the past that's like an hour talking about just why sugar/fructose is so bad when compared to glucose. However it also talks about how in nature the only source of fructose comes with its own antidote in the form of fiber. Now that's not to say that binging on fruit is a just fine, but it is a whole lot better than juice or soda.

Could this be the video? It's Dr. Lustig...great info. ‪Sugar: The Bitter Truth‬‏ - YouTube

[Lewis]

I
I have been binging on fruit lately. 11 peaches on Sunday, a pound of plums yesterday...to no ill effects. I can to a possible conclusion that fructose works great for my metabolism because I burn fat, not glucose.

There's actually more glucose than fructose in the plums, though. Best I can find:

A serving of five dried plums provides 26 grams of carbohydrates and 15 grams of sugars, mainly glucose (10 grams) and fructose (5 grams. There is almost no sucrose.

Nutrition Composition | California Dried Plums

As for the effects of fructose, I don't suppose a moderate amount of fruit, fibre and all, is likely to do anyone much harm so long as their diet is otherwise good. It's table sugar (sucrose) and HFCS, particularly in drinks, that are the problem

I don't know but I suspect the answer to why you could go a bit crazy on the fruit and not notice any ill effects might simply be that you can do that once in a while. It's if you did it every day that you'd run into problems.

I was interested to find out that Chris Kresser, and one or two other people, recommend buying a cheap glucometer and checking your blood glucose after meals now and then simply to get an idea of how long it takes to get back down to normal. It would be interesting to know what the figures for your blood sugar were at various periods after a normal meal of yours and at the same intervals after you ate the pound of plums.

[MamaGrok]

I have no idea on the science of it, but I like to keep in mind that fruits as we know them today aren't very natural. Sweet bananas are less than 200 years old; I'm pretty sure apples & grapes, etc., are all hybridized to be much bigger and sweeter than in nature, etc. So having one here and there is fine for me, but I don't want to go crazy with them, since that's really a relatively new (historically speaking) possibility and our bodies haven't adapted to it yet.

[wiltondeportes]

Ok...interesting thoughts. They seem mostly middle of the road compared to my proposal. Obviously I don't eat this much fruit everyday...it was my friend's peach tree being at full ripeness and being at a farmers market after hearing how good plums are (and never really eating them before). I'll watch that video Umya posted when I get a chance.

[js290]

http://www.nytimes.com/2011/04/17/ma...pagewanted=all

[inquisitiveone]

I have no idea on the science of it, but I like to keep in mind that fruits as we know them today aren't very natural. Sweet bananas are less than 200 years old; I'm pretty sure apples & grapes, etc., are all hybridized to be much bigger and sweeter than in nature, etc.

An excellent post by Denise Minger addresses this issue. For those who don't want to read it all, the major points IMO are: 1] berries aren't lower in sugar (especially fructose) compared to many other easily obtainable fruits; 2] cultivated fruits generally don't have more carbs than wild ones (research limits the generalizability of this point); and 3] the modern-day idea of what fruits are like is very limited in scope, and therefore biased. Some African fruits are enormous, very sweet, or both.

[Hunt3R]

There's more to fructose metabolization than just straight to the liver, then to fat, then burn for energy. Fructose may be "mostly harmless" in small amounts but I don't think it should be thought of as an energy source. Here's one study that explains why: Fructose, weight gain, and the insulin resistance syndrome

Fat is our "cleanest" energy source. Some glucose intake daily is beneficial but IMO the majority should probably come from starchy root veggies as they are superior to fruit in that they contain mostly glucose and little to no fructose.

Also, there are more concerns to eating that much fruit other than just energy metabolism. Eating that much fruit could put you at risk for an overgrowth of harmful bacteria in your gut, which are also able to metabolize fructose & glucose. I know this because it happened to me. I thought being "paleo" meant all the fresh fruit I could eat. Everyone loves fruit and it's perfectly healthy, right? So I ate a lot everyday, maybe 10+ servings a day. Now I'm struggling to get rid of a candida infection in my gut by having to be extremely strict about what I eat. No sugar of any form except 1-2 servings of fruit a day max for me now.

[wiltondeportes]

An excellent post by Denise Minger addresses this issue. For those who don't want to read it all, the major points IMO are: 1] berries aren't lower in sugar (especially fructose) compared to many other easily obtainable fruits; 2] cultivated fruits generally don't have more carbs than wild ones (research limits the generalizability of this point); and 3] the modern-day idea of what fruits are like is very limited in scope, and therefore biased. Some African fruits are enormous, very sweet, or both.

There's more to fructose metabolization than just straight to the liver, then to fat, then burn for energy. Fructose may be "mostly harmless" in small amounts but I don't think it should be thought of as an energy source. Here's one study that explains why: Fructose, weight gain, and the insulin resistance syndrome

Fat is our "cleanest" energy source. Some glucose intake daily is beneficial but IMO the majority should probably come from starchy root veggies as they are superior to fruit in that they contain mostly glucose and little to no fructose.

Also, there are more concerns to eating that much fruit other than just energy metabolism. Eating that much fruit could put you at risk for an overgrowth of harmful bacteria in your gut, which are also able to metabolize fructose & glucose. I know this because it happened to me. I thought being "paleo" meant all the fresh fruit I could eat. Everyone loves fruit and it's perfectly healthy, right? So I ate a lot everyday, maybe 10+ servings a day. Now I'm struggling to get rid of a candida infection in my gut by having to be extremely strict about what I eat. No sugar of any form except 1-2 servings of fruit a day max for me now.

Thank you two. These are exactly the two arguments inside of my head. I think fruit is fine from a Paleo perspective because there's a decent chance there was sweet fruit back then. On the other hand, it was only during small seasonal periods and they served a negative purpose on the body to make them conserve energy during the winter months. Plus, fruit is a great water storage if you are dehydrated.

In modern terms, I have to agree with you, Hunt3r. That study was not attacking fruits of course (which include fiber with their fructose to slow absorption), but I have to agree with the later parts of your post.