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Fructose???

Hey, guys. What’s this sudden “negativity” toward fructose (fruit sugar) that is suddenly showing up in all the bodybuilding literature? Is it a beef with fructose in general OR how it is showing up everywhere in the food supply? (like Soy) What about all the beneficial phytochemicals in fruit?


I don’t have a grasp on this one, guys. Would love your thoughts.

High fructose corn syrup is a really cheap sweetner found in a lot of comercial processed foods. The trouble with fructose is that it can only be broken down in the liver and then stored as glycogen in the liver (not muscle glycogen). In moderation its ok and keeps liver glycogen top off but the problem is if liver glycogen is full (which it usually is after eating bunch carbs), then excess fructose is converted directly to trigycerides (can you say fat). Fructose in moderation is ok but if consuming to much, then promote fat gain. This usually isn’t a problem but with more and more products sweetned with cheap high fructose corn syrup, a person needs to watch their fructose consumption to keep it under a max of 50 grams a day. Fructose is metabolized differently than other carbs.

Well, I think of it this way…that fructose is primarily stored as liver glycogen. Seeing as liver glycogen capacity is only about 70g…it looks to me as if, when bulking, that fruit calories are just going to be stored as fat. That being said though, I do think fruit has it’s place, especially while dieting. (I use it to fuel my workouts when eating Paleo-style)

the problem with fructose is that its main job to feed the liver, not muscle tissue. If you are looking to fuel your muscles, then fructose is not the type of carbohyrate you should be consuming. A piece of fruit here and there isn’t a problem tho, its when you start to get alot of your carbs from fructose, thats when there is a problem

I did read a little more and picked up a little more background. There appears to be two main arguments “against” fructose: 1)The ineffeciency of fructose to restore liver glycogen and 2) It’s greater contribution and effeciency at, and to, fat deposition.


I don’t eat a lot of fruit(an apple in my a.m. oatmeal and strawberries and/or blueberries in my AP), but it SEEMS like this is a case where the BENEFITS of fruit FAR outweigh any negatives. Besides…liver re-uptake and replenishment is easily taken care of with “Surge” and other carbs, and we can talk for DAYS on how to deal with fat deposition.


Is it just me, or are the “pundits” way off in this one?

Read Cy Willson’s article on this topic at T-mag called “The Forbidden Fruit?” He likes fructose for the most part and backs up what he says with solid info. The high fructose corn syrup stuff is bad of course, but fructose itself is not bad at all from fruit, although there are better sources for post-training.

I recently read somewhere (tho unfortunatly I can’t remmember where sorry) that fruit today is bred for sweetness (to improve taste to boost sales, makes sense eh?), so while our ancestors did eat fruit it was wild fruit thus probably less fructosy.

Yeah, TEK, but I always had a thought in the back of my mind that the article was written to correspond to Grow!'s inclusion of fructose as an ingredient.

No, it was written because I got sick of hearing guys say things like, “Oh dude, I don’t eat fruit, because it makes you fat.” Just as I hate hearing guys talk about how they’re “waiting for their gear to ‘kick in’ and start working” and how they’re "cycling off cuz my receptors are ‘dirty’ and things of that nature. Just gets annoying when people spout off invalid ideas or only partial truths and act as though they are facts.

Thanks, guys! Once again, this Forum AND my own research have helped me formulate my own opinion. My final take?


1)Fruit is good for you in moderation (like a lot of things). Don’t be “afraid” of it. (Which is essentially what Cy was saying in his article).


2)Avoid foods with loads of fructose syrup as a sweetener.


3)Deal with fat deposition and the replinishing of glycogen stores by much more efficient and time-proven methods.


So…fructose…not a panacea…but also not the “evil” substance that many have made it out to be…

Yep, you summed it up very well.

And remember not all fruit contains fructose as its main sugar, grapes for example

So-called high fructose corn syrup are not all that high in fructose. Mostly glucose. “High” is relative.