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Glucose = Sugar = Bad


Hey guys, it is common knowledge that if you want to build a good physique then you can't consume lots of simple sugars. However complex sugars that are found in bread and pasta are supposed to be good.
I just found out that when someone consumes complex sugars, they get decomposed into glucose and fructose... I'm am extremely confused.
What exactly do simple sugars (such as glucose, fructose and sucrose) do that is bad for building muscle, and why is it not true when they come from complex sugars??



You might be best off researching carbohydrate metabolism in a physiology textbook, as apposed to looking for a detailed forum response on a topic like this.


even though it's "common knowledge" that simple sugars are "bad", as is often the case, common knowledge is incorrect.

all carbohydrates, both simple & complex, are broken down to glucose & fructose and are processed the same way. The reason people say to avoid simple sugars is that they are typically over consumed and are deficient in numerous vitamins & minerals. However, when it comes to body composition, whether you choose simple or complex carbs, it's the total amount that matters, NOT the type.


Simple sugars are actually excellent for building muscle, specifically by increasing or refilling muscle glycogen(glucose packed together in chains/branches) stores in the sarcoplasm(the liquid supporting volume) of the muscle cell.

However, big spikes in blood sugar also contribute very heavily to increasing the volume of Fat cells unless consumed post/peri workout(when your muscle cells are more sensitive to insulin and absorb glucose more readily) or if you are very lean(your fat cells have less surface area and are less sensitive to insulin).

Also, because glucose cannot be moved out of the skeletal muscle directly, there's no need to worry about eating sugars or other carbohydrates to keep them filled once you've past the pwo window and, when you're leaner, in the morning(breakfast).

Complex carbohydrates are better than simple sugars, because they are absorbed more slowly and don't elevate blood sugar as much, but still contribute to increasing the Fat cell stores with the noted exceptions.

Hope that clears things up.



x2. This.

I would also like to add that complex carbs are often higher in fiber which may help you feel fuller for longer. This may help you stick to your meal plans and not binge eat because you feel hungry. Bottom line, for body comp carbs of any kind are the same.


good way to incorrectly blanket statement things here. wow


Elusive, I agree with you up to a point, EXCEPT in the instances of bloating etc occuring due to wheat, oats, whatever. For example, if I'm eating a few serves of oats every day I bloat up a bit, so whilst my fatloss/muscle gain etc stays the same as it would have been if i had eaten an equal quantity (calorifically) of brown rice, I look a bit 'fatter'. So that's the only thing I think to look out for - if you don't mind the bloat then yes, I tend to agree with jmo (as usual) and elusive.


Let me be more specific. For body comp, the carby foods you choose will not matter. Meaning white bread or whole wheat bread. rice cakes or oatmeal. Fat free potato chips or fruit. All the same. If you feel differently, then you've never actually tried it out for yourself. Like it was said above by JMo, its the amount of carbs you eat, not where they come from.


Well, I would agree with you here. If a certain food is bloating you and because of that, derails ur mental focus on the cut you should avoid them. Just curious, have you noticed if rice bloats you at all?


Because I know that bodybuilders are prone to extremes, I want to make sure that what I'm saying won't be misconstrued as a recommendation to eat nothing but "junk food".

Fruits and veggies have their place in virtually any diet, as do unprocessed carbs like oatmeal, rice, and potatoes. These foods are all nutrient dense, generally high in fiber and water, and will likely keep someone fuller and less prone to binge than their refined counterparts.

However, there is no "magic" behind these foods. They don't make you less fat than a calorie-matched portion of an "unclean" food. For example, if your meal plan calls for 50g of carbs to be eaten at a meal, you can get those carbs from grapefruit, or from fruity pebbles, it will make no difference IF the total amount is the same. But you have to ask yourself, how often in the real world is someone likely to eat 50g of carbs from grapefruit?

Moreover, how likely is it that someone would LIMIT themselves to only eating 50g of carbs from fruity pebbles? Not very likely unless they have the self control necessary to strictly measure out their portions. And if someone has the self control to do that, it's unlikely that they'll have a problem controlling their weight in the first place.


This is what I was talking about in my other post just now. I disagree with the conclusion.

Some carbs are going to provide more fiber, vitamins, etc and be better for digestion. Ultimately fruit is going to probably have a more positive effect on health than isocaloric treatments of potato chips. More importantly from the body composition standpoint, there can be quite a big difference in satiety between liquid carbohydrates, "junk" carbohydrates, and a more volumous fibrous carb like an apple. And simply assuming a trainee is getting sufficient micronutrients is a big assumption. And simply saying "well then eat the same amount" may be fine in theory but not in practice. A person drinking soda or eating potato chips vs. getting the same calories from fruit is not going to be able to effectively gauge what their body wants and the difference in satiety and consumption is going to be very harmful long-term. Once again, you don't actually know how many calories you need, you have a general idea and it changes day to day and throughout life. Adding confounding factors like foods with little nutritional value is not going to help.

Lifestyle, lifestyle. Integrate it. The theory is nice but practical application is crucial, especially when we're talking about advising people who want the best results in health and body composition and are in it for the long run.


right, I agree.


Exactly what I was saying, but more succinct :slight_smile:

No, I eat brown rice as opposed to white and I haven't had any bloating problems - yet. 3 cups cooked per day on average at the moment.

The main foods that seem to bloat me up are oats and wheat to a lesser extent - I avoid both when cutting not just for the psychological aspect of dieting but also because if bloating is fluctuating it's hard to get an accurate gauge as to where you are.

And for the above poster yes, it's brown because of the (slightly) more fibre and micronutrients etc.


Glucose is actually a winner.

Fructose is your worst nightmare, however.


I sincerely hope you're joking.

Though I've learned never to underestimate the intelligence of the posters on this board.


Wait so if I eat more than an apple a day I won't keep the doctor away?


I'd agree with this in theory assuming the person was able to get all of their micronutrients. Hopefully it's been drilled in enough to this forum that calories are what matter most. Basically, it provides a little wiggle room to stray from a superclean, bland diet as long as portions are controlled.

I have a feeling many people in the dietetic field disagree with this but it definitely works. A big ass bowl of oatmeal or a package of pop tarts in the morning will have the same effect on body composition.


Unforntunately, alot of people in the dietetic field have no practical hands on experience with body compisition diets. They just know what they've learned from their text books. I'm sure Brick can attest to that. Hes probably worked with some real idiots. lol.

I'm currently in the didactic program and not to far away (hopefully) from being an R.D myself. I can tell you, judging by the students in the program, alot of the up and coming R.D's are completely clueless.


that's exactly it, wiggle room. people can't seem to grasp the concept of moderation; with them it's either 100% clean or nothing but processed junk.

what they don't seem to consider is that eating mostly unprocessed, nutritious food with moderate amounts of "fun stuff" can work just as well as completely cutting out all sugar (or saturated fat, or whatever one deems "unclean").


so glucose and fructose are the exact same to you? if you think they are different, and metaboilsed differently (which they are), you should stop saying they are the exact same, and the body doesn't care which you consume.