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Training & Nutrition Learn how to develop a training schedule that's good for you. What should you eat and drink on your ride? Learn everything you need to know about training and nutrition here.

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Old 03-05-06, 06:44 PM   #1
srrs
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simple vs. complex carbohydrates

For some reason, I find it difficult to get enough complex carbohydrates into my diet. I just don't really eat bread, pasta, rice, etc. very often. I do, however, eat a lot of fibrous vegetables, and a lot of fruit. If I am getting fruit sugars and fiber, is there any need for me to eat whole wheat bread and brown rice? Doesn't it all end up glucose in the end? Are there any specific health or training advantages to complex carbs? Are there particular times (breakfast? after training?) that I should be eating simple or complex carbohydrates specifically?

Thanks!
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Old 03-05-06, 11:02 PM   #2
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yeah, what srrs asked.

i've been 'supplimenting' my diet with sugar. Every thing ive
ever read about training usually says they avoided sugar. Why?
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Old 03-06-06, 12:08 AM   #3
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Typically, you want simple carbs when you're exercising and for recovery due to faster absorption rates. Complex carbs at all other times.

The carbs in fruits and veggies are actually simple sugars that absorb fairly quickly. The higher percentage of fructose actually diffuses passively through the intestional wall, much faster than glucose from the breakdown of starches. It's misleading to use the GI with fruits & veggies because fructose doesn't trigger the insulin-response, but the carbs are still making it through.

The only catch with eating primarily veggies and fibrous stuff is that you don't get enough glucose and proteins after a ride for optimum recovery. What's so hard about adding some dirty-rice and chilli to your steamed veggies?
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Old 03-06-06, 12:09 AM   #4
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Do a search for "Glycemic Index" ... that'll give you a good idea of what to eat and why. The lower the glycemic index, the better.

It is a very good idea to limit the amount of simple sugars in your diet. Simple sugars are things like table sugar (the stuff you put into your coffee, or on your cereal), chocolate bars, candies, sugared beverages, etc. Fruit and veggies are all right because they've got the fiber aspect to them. It's the extremely simple, heavily processed, stuff that is not good.

The reason simple sugars should be limited is because they tend to spike your blood sugar level and then, as soon as they are burnt off, which happens fairly rapidly, your blood sugar level drops ... often lower than it was before. This drop in blood sugar level triggers the hunger sensors in the brain, and next thing you know, you're eating again. It's a great way to gain weight. Also, there is some evidence that this constant spiking and dropping can cause defects in the pancreas which may lead to diabetes.

However, if you eat complex carbs, fats, and/or proteins, your blood sugar level will go up gradually, and will remain steady for a while before slowly dropping. You won't get hungery as quickly and it is easier on your body.
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Old 03-06-06, 07:48 AM   #5
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Originally Posted by DannoXYZ
The only catch with eating primarily veggies and fibrous stuff is that you don't get enough glucose and proteins after a ride for optimum recovery. What's so hard about adding some dirty-rice and chilli to your steamed veggies?
I'm trying to get better about it.. One of my earlier posts addressed the fact that for awhile I was limiting calories excessively (I've sense rethought this and have added a lot more calories into my diet). Part of this meant eating very few carbohydrates. I wasn't on a low-carb diet, I just never ate anything calorie-dense, which included pretty much all complex carbs. You know how people say they can't break the fast-food habit? I'm way on the other end of the spectrum. I can't break the salad habit. I'll often fix meals, and only after I'm done with prep and sitting down to eat will I realize that I've prepared three kinds of veggies, some tofu, and an apple for dessert - no complex carbs.

One of the changes I made was to add protein shakes once or twice a day, because on a recent trip to the dietician she told me I didn't get enough protein. The way I make them they're full of fruit. They tend to be for breakfast or post-ride. So, I was wondering if this is an ok way to go about things - if this covered both the nutritional bases of carbohydrates and proteins.

It sounds like the fruit is second-best, in that it does not spike the insulin like other sugars do, but is quickly absorbed. But it also seems that in order to best regulate my energy levels I need to add some whole wheat pasta. However, it also sounds like the difference between these foods is basically in the absorption rates, so it seems like if I ate one bowl of brown rice I could approximate the effect by eating three apples over a few hours. Is that correct?
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Old 03-06-06, 01:40 PM   #6
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Originally Posted by Machka
Do a search for "Glycemic Index" ... that'll give you a good idea of what to eat and why. The lower the glycemic index, the better.
(plus the rest of Machka's post)

Good answer! Some people like the glycemic index, some don't. I personally think it makes sense.
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Old 03-06-06, 02:08 PM   #7
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Originally Posted by srrs
It sounds like the fruit is second-best, in that it does not spike the insulin like other sugars do, but is quickly absorbed. But it also seems that in order to best regulate my energy levels I need to add some whole wheat pasta. However, it also sounds like the difference between these foods is basically in the absorption rates, so it seems like if I ate one bowl of brown rice I could approximate the effect by eating three apples over a few hours. Is that correct?
Sounds good. Overall calorie-intake would be about the same over that time-period.

However, one must be careful of the differences between fructose and glucose. GI only accounts for glucose and only partially models what happens in the body. Fructose goes in passively and doesn't trigger the insulin response, yet that fructose is still converted to glucose before being used for ATP-production. Excess amounts are still converted to fat later.

The problem with HFCS-high fructose corn syrup used in sodas and just about every other food-product out there like salad-dressings, ketsup, jams/jellies, etc. is that the higher-percentage of fructose throws off the usefulness of GI. Your insulin-response reacts as if you've eaten 400-calories, but in reality, you've actually eaten 700-calories with the extra fructose sneaking by unnoticed. The problem with this is that the resultant lower increase in insulin and leptin levels doesn't satiate your hunger, you still feel hungry and want to eat more. That's one of the problems with drinking sodas with HFCS, you can take in all these calories, but your body reacts as if you'd done nothing and you're still hungry. So counting total-calories along with monitoring GI gives you a more comprehensive picture of what you're eating.
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Old 03-06-06, 03:56 PM   #8
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Originally Posted by DannoXYZ
The problem with HFCS-high fructose corn syrup used in sodas and just about every other food-product out there like salad-dressings, ketsup, jams/jellies, etc. is that the higher-percentage of fructose throws off the usefulness of GI. Your insulin-response reacts as if you've eaten 400-calories, but in reality, you've actually eaten 700-calories with the extra fructose sneaking by unnoticed. The problem with this is that the resultant lower increase in insulin and leptin levels doesn't satiate your hunger, you still feel hungry and want to eat more. That's one of the problems with drinking sodas with HFCS, you can take in all these calories, but your body reacts as if you'd done nothing and you're still hungry. So counting total-calories along with monitoring GI gives you a more comprehensive picture of what you're eating.
Actually, HFCS's fructose content is either 42% or 55% depending on formulation*, with the remainder made up of glucose (plus a tiny amount of higher sugars). This is roughly the same composition as what regular sugar (sucrose) breaks down to (50/50 glucose/fructose). HFCS is called "High Fructose" Corn Syrup because it is high in fructose relative to regular corn syrup (dextrose), which is mostly glucose.

HFCS-55 is what's typically used in soda and other sweet drinks, while HFCS-42 is used in less sweet things (e.g. ketchup, etc.).

*American Journal of Clinical Nutrition, #58 supplement 5, L. Mark Hanover and J. S. White (1993)
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Old 03-06-06, 05:14 PM   #9
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Originally Posted by DannoXYZ
Sounds good. Overall calorie-intake would be about the same over that time-period.

However, one must be careful of the differences between fructose and glucose. GI only accounts for glucose and only partially models what happens in the body. Fructose goes in passively and doesn't trigger the insulin response, yet that fructose is still converted to glucose before being used for ATP-production. Excess amounts are still converted to fat later.

The problem with HFCS-high fructose corn syrup used in sodas and just about every other food-product out there like salad-dressings, ketsup, jams/jellies, etc. is that the higher-percentage of fructose throws off the usefulness of GI. Your insulin-response reacts as if you've eaten 400-calories, but in reality, you've actually eaten 700-calories with the extra fructose sneaking by unnoticed. The problem with this is that the resultant lower increase in insulin and leptin levels doesn't satiate your hunger, you still feel hungry and want to eat more. That's one of the problems with drinking sodas with HFCS, you can take in all these calories, but your body reacts as if you'd done nothing and you're still hungry. So counting total-calories along with monitoring GI gives you a more comprehensive picture of what you're eating.
Yeah - that's why I never drink soda or juice, and eat low-sugar versions of jelly and the such. I always try to get as much volume for the fewest calories as possible. This means lots and lots of fresh fruits and veggies!
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Old 03-06-06, 05:16 PM   #10
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I always try to get as much volume for the fewest calories as possible.
Thats why I always eat the fruit instead of just drinking the fruit juice.
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Old 03-06-06, 07:05 PM   #11
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Originally Posted by DannoXYZ
fructose actually diffuses passively through the intestional wall
there is a carrier involved, it's facilitated diffusion!
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Old 03-07-06, 06:30 AM   #12
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Yes, fructose is absorbed by facilitated diffusion through enterocytes and doesn't rely on the sodium-ion exchange-pump that's required for active-transport of glucose against the concentration gradient. The effective-transfer rates are:

glucose = 26.5 mumol/min*30cm
fructose = 133.3 mumol/min*30cm

With fructose being absorbed over 5x faster, it makes the difference between high-GI vs. low-GI carbs close to irrelevant if you're eating high-concentrations of simple sugars with fructose. This mechanism actually used in many sports-drinks to boost the 200-250 cal/hr digestion & absorption limit of glucose.

There's been a steady movement from using HFCS-55 to higher levels of fructose in 80-95% ratios to boost the sweetening effects (HFCS-42 is used as an intermediary to produce HFCS-55 or higher). There's numerous health-effects of such a trend:

University of Florida - Scientists find sugar may have a sour side
SFgate - Sugar coated. We're drowning in high fructose corn syrup.
PeerTrainer - Fructose and Fat
Obesity Research - Carbohydrates and Increases in Obesity: Does the Type of Carbohydrate Make a Difference?
AmJournal Clinical Nutrition - Consumption of high-fructose corn syrup in beverages may play a role in the epidemic of obesity
AmJournal Clinical Nutrition - Fructose misuse, the obesity epidemic
Corn Syrup: Bittersweet Story.pdf

The main problem with fructose is that you ingest calories, yet it does nothing to elevate insulin and leptin levels to relieve your hunger sensations. You're better off eating the same number of calories in glucose instead. Fructose has also been implicated in insulin-resistance as well.

Last edited by DannoXYZ; 03-07-06 at 07:18 AM.
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Old 03-07-06, 07:25 AM   #13
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There's been a steady movement from using HFCS-55 to higher levels of fructose in 80-95% ratios to boost the sweetening effects (HFCS-42 is used as an intermediary to produce HFCS-55 or higher).
I'm not arguing the health effects of increased fructose.

What I'm saying is that HFCS doesn't have significantly increased fructose as compared to other simple sugars (sucrose, honey, maple syrup, brown sugar, etc -- they all reduce to basically half and half fructose and glucose).

The difference between HFCS-42 and HFCS-55 is small enough that it's not even required to distinguish it in labeling. However, if what you are saying is true, that we are being served 90% fructose in HFCS, I think we have a major health scandal on our hands.

Do you have anything to support what you are saying about this 90% fructose bit? I did not see anything corroborating that in the studies and articles you posted. Most of the "studies" linking HFCS and obesity rely on correlation (a la, "HFCS is appearing in more foods, and more people are getting obese, hence HFCS causes obesity!"), but they do not actually prove causation. They cannot, without bringing along all of the other simple sugars.
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Old 03-07-06, 07:40 AM   #14
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HFCS with very high fructose concentrations are being used in products labeled as "light" or "low-calorie" due to its high sweetness.

AmJournal Clinical Nutrition - Increased consumption of refined carbohydrates...
Bodybuilding.com - Types Of Sweeteners
Secretariat of the Pacific Community #66.doc

If you dig deeper, you'll find studies showing fructose converts to triglycerides more readily than glucose. Not to mention insulin-resistance and glucose-intolerance effects.

Nutrition&Metabolism - Fructose, insulin resistance, and metabolic dyslipidemia
AmJournal Clinical Nutrition - Fructose, weight gain, and the insulin resistance syndrome

Last edited by DannoXYZ; 03-07-06 at 07:51 AM.
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Old 03-07-06, 08:57 AM   #15
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Originally Posted by DannoXYZ
The main problem with fructose is that you ingest calories, yet it does nothing to elevate insulin and leptin levels to relieve your hunger sensations. You're better off eating the same number of calories in glucose instead. Fructose has also been implicated in insulin-resistance as well.
Wait a second.. This makes sense when you're talking about foods that have very little substance other than the fructose or sucrose (i.e. soda or coffee/tea heavily sweetened with table sugar for example). In that case, the table sugar converts to glucose, making you feel fuller so you stop ingesting calories - it's like a backup for your self-control. But I assume that, if you are eating fructose in combination with something to make you feel full (i.e. the fiber in fruit), such that you don't need that backup because you feel full after a limited number of calories (or even if you know the calorie content of, say, one small cup of soda and are able to limit yourself to it) fructose is better than glucose, because it doesn't spike the blood sugar, sparking cravings and making you hungry later?
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Old 03-07-06, 09:34 AM   #16
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If you dig deeper, you'll find studies showing fructose converts to triglycerides more readily than glucose. Not to mention insulin-resistance and glucose-intolerance effects.
one reason why some are blaming high soda consumption as a factor in dysmetabolic syndrome/ metabolic abnormalities.

especially in kids. bummer there is frequently soda machines in school cafeterias. whether HFCS/soda consumption is a major culprit of weight gain in youths (or americans in general) or not....makes you wonder
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Old 03-07-06, 09:38 AM   #17
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Originally Posted by DannoXYZ
HFCS with very high fructose concentrations are being used in products labeled as "light" or "low-calorie" due to its high sweetness.

AmJournal Clinical Nutrition - Increased consumption of refined carbohydrates...
Bodybuilding.com - Types Of Sweeteners
Secretariat of the Pacific Community #66.doc

If you dig deeper, you'll find studies showing fructose converts to triglycerides more readily than glucose. Not to mention insulin-resistance and glucose-intolerance effects.

Nutrition&Metabolism - Fructose, insulin resistance, and metabolic dyslipidemia
AmJournal Clinical Nutrition - Fructose, weight gain, and the insulin resistance syndrome
Danno, those things are saying that additional fructose is being added as a sweetener (e.g. in addition to HFCS). And again I'm not arguing the effects of higher overall fructose intake.

But you seem to be trying to single out HFCS as a bad guy, when it is not any worse (or better) than other glucose/fructose sweeteners. In other words, you are not doing yourself any favors by choosing a drink sweetened with sugar/sucrose as compared to that same drink sweetened with HFCS, or vice-versa.
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Old 03-07-06, 09:46 AM   #18
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Originally Posted by mx_599
one reason why some are blaming high soda consumption as a factor in dysmetabolic syndrome/ metabolic abnormalities.

especially in kids. bummer there is frequently soda machines in school cafeterias. whether HFCS/soda consumption is a major culprit of weight gain in youths (or americans in general) or not....makes you wonder
It makes you wonder, but if you actually read the studies, they are talking about overconsumption. If they were to ban HFCS food manufacturers were forced to replace it with "traditional" sweeteners such as plain sugar, we'd be 'wondering' about that, too.

No study has actually said HFCS is a direct cause of obesity. They say, "trends in HFCS consumption track with increased obesity". Anyone who's had a lick of science or statistics knows that correlation is not causation and it's intellectually dishonest to suggest that it is. You might as well say that computers cause obesity . . . use and consumption of computers is up in the past 30 years, and obesity is up in the past 30 years, hey a lot of people use computers, computers must cause obesity! Pure crap.

There was a study just published the other day that "concluded" that high school kids lost weight when they replaced regular soft drinks with zero calorie soft drinks. Wow! What a @!#$%ing revelation! Sugary soft drinks must be bad!!! Well, they're not. They're not good either, but the actual conclusion that should have been reached is . . . . drumroll please . . . if you reduce caloric intake you will lose weight.
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Old 03-07-06, 09:56 AM   #19
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It makes you wonder, but if you actually read the studies, they are talking about overconsumption. If they were to ban HFCS food manufacturers were forced to replace it with "traditional" sweeteners such as plain sugar, we'd be 'wondering' about that, too.

No study has actually said HFCS is a direct cause of obesity. They say, "trends in HFCS consumption track with increased obesity". Anyone who's had a lick of science or statistics knows that correlation is not causation and it's intellectually dishonest to suggest that it is. You might as well say that computers cause obesity . . . use and consumption of computers is up in the past 30 years, and obesity is up in the past 30 years, hey a lot of people use computers, computers must cause obesity! Pure crap.

There was a study just published the other day that "concluded" that high school kids lost weight when they replaced regular soft drinks with zero calorie soft drinks. Wow! What a @!#$%ing revelation! Sugary soft drinks must be bad!!! Well, they're not. They're not good either, but the actual conclusion that should have been reached is . . . . drumroll please . . . if you reduce caloric intake you will lose weight.
yeah i know. i just think the connection of fructose to triglycerides is interesting. but i skimmed what you guys wrote real quick and see what you're saying about the others breaking down to the same components.
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Old 03-07-06, 10:23 AM   #20
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yeah i know. i just think the connection of fructose to triglycerides is interesting. but i skimmed what you guys wrote real quick and see what you're saying about the others breaking down to the same components.
Again, I'm not questioning the connection of fructose to triglyceride levels or any of the other health risks of increased fructose. But what I do question is the suggestion that the presence of HFCS automatically means elevated fructose. It doesn't, as compared to sugar (or honey, or maple syrup, etc.).

The conclusion that one should reach from reading Danno's info is that you need to watch out for additional fructose (as a separate ingredient -- indeed, seeing more of this). And the conclusion one should reach from this whole thread is that you should watch your intake of simple sugars as a percentage of your overall caloric intake.

But you should not reach the conclusion that you are somehow getting a health benefit of choosing, say, honey as a sweetener as compared to HFCS.
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Old 03-07-06, 11:13 AM   #21
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ok, so simple sugar spikes the blood sugar up and then it goes way down.
Apparently, insulin mitigates this somewhat? and protein causes insulin production?

Another question, why, when we excercise, are simple sugars ok. Are we creating
more insulin by excercising?
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Old 03-07-06, 12:02 PM   #22
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I'm not singling out fructose, it's just one component of overall health and diet. Just like how a lot of people look at GI as the single holy-grail thing to monitor, I just wanted to point out that there are multiple inter-related factors; some of which may be contradictory. Yes, the most relevant and biggest contributor to the majority of health issues we face to day is simply volume, eating way, way too much for the level of activity that we do. Life isn't exactly life & death nowadays where you have to spend hours tracking down and foraging for food everyday, thus making you get some exercise for the meager calories that you get to consume each day. Now we've got an abundant number of choices in mega-calorie super-sized meals and a lot of people just sit behind a desk all day.

Monitoring GI, playing around with types of food and timing meals, juggling complex vs. simple carbs, fructose vs. sugar vs. artificial-sweeteners are just the tip of the iceberg as far as addressing the real problem, simply eating way, way too much.


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ok, so simple sugar spikes the blood sugar up and then it goes way down.
Apparently, insulin mitigates this somewhat? and protein causes insulin production?

Another question, why, when we excercise, are simple sugars ok. Are we creating
more insulin by excercising?
It's not the actual sugar we have to worry about, it's the concentration. Simple carbs and table-sugar (sucrose) are digested fast and goes into your bloodstream quickly. This raises blood-glucoses and leptin levels which gives your brain the "I'm full, I'm happy" feeling and you can stop eating. That's why they also tell you to eat slowly, so that the food first entering your body has a chance to digest and get into your bloodstream. Otherwise, you'll continue to eat well beyond the volume that's necessary to raise your blood-sugar due to the time-delay of digestion. Proteins take longer to digest and raises insulin moderately.

Depending upon how high that blood-sugar gets, a certain amount of insulin is pumped in to regulate it. Insulin triggers your muscle-cells to absorb glucose from the bloodstream and convert to glycogen to replenish its energy stores. At the same time adipose fat-tissue is signaled to convert the glucose into fats and store it. Perfectly normal biology. The problem comes in with sedentary lifestyles where your muscle-cells aren't exercised and their glycogen stores (2000 calories total) are fully stocked up. Then all of the excess glucose and protein in the bloodstream goes into building up fat-storage. The problem here is not insulin or glucose, it's that you're eating food when you don't need it, and the excess is converted into fat.

What happens when you eat too much simple-carbs/sugars is it increases your blood-sugar by A LOT. Then the body dumps in A LOT of insulin to quickly make your cells absorb that glucose. However, like with eating quickly, there's an overraction and time-delay. The extra insulin ends up overcompensating and makes your cells suck up too much glucose from the bloodstream. This lowers your blood-sugar by too much and your brain, which burns primarily glucose, ends up not having enough energy and this is the cause of the laziness you feel after a big meal (also stomach hoards blood for digestion, further starving the brain of glucose).

As you can see, in sedentary people with fully stocked-up glycogen stores, excess glucose & protein mostly gets converted into fat. By eating more complex carbs, or in srrs's case, simple-carbs trapped within fibre of fruits & veggies, the digestion-rate and glucose-absorption into the bloodstream is slower. This triggers less of the insulin-response and a less immediate conversion to fat. The slower digestion and more steady blood-glucose gives you time to burn off that meal in activity over the next couple of hours as it digests rather than having it go straight to fat. That's the basis of GI.

However, when you're working out and exercising (and recovery afterwards), the goal is different, you want to get glucose into your cells as fast as possible to replenish the glycogen that's being consumed. In which case, you want low-GI simple carbs found in energy drinks & gels. These spend the least amount of time sitting around in your intestines and gets to the cells quickly. Due to the limited digestion-rate of 200-250 cal/hr, ingested carbs is always playing a losing catch-up game with the depleting glycogen stores, your blood-sugar level will always be declining during exercise if you're working out at a rate of more than 200-250 cal/hr.

There's some minor debate about eating too much too far ahead of time before a workout and triggering a dip in blood-sugar due to the insulin-spike. However, the results of studies have shown no impact on performance whatsoever. That's because your glycogen stores are fully-stocked and the low blood-sugar just indicates that the meal has been transfered from your bloodstream into your muscle-cells, right where you want it. It's just that your brain that feels sluggish from low blood-sugar, but your muscles are fully stocked and ready to go!

As for the final question, when you're exercising, blood-sugar and insulin drops, the analogue to insulin, glucagon is actually increased. This has the opposite effect as insulin, triggering your cells with high glycogen-stores (unused muscles) to dump its supply into the bloodstream and increasing blood-sugar levels. Also triggers your fat-cells to dump its fat-stores into the bloodstream to supply energy to the working muscles.

Last edited by DannoXYZ; 03-07-06 at 12:36 PM.
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Old 03-07-06, 02:21 PM   #23
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blood-sugar and insulin drops, the analogue to insulin, glucagon is actually increased.
glucagon also has a stimulatory effect on insulin...didn't see you mention that
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Old 03-07-06, 02:23 PM   #24
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Another question, why, when we excercise, are simple sugars ok. Are we creating
more insulin by excercising?
in lay terms, exercise acts as insulin in regards to glucose uptake (from blood to working musc)

that is why diabetics can have such success with exercise.
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Old 03-09-06, 11:29 AM   #25
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srss - Have you been able to "digest" all of this? There will be a test later.
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