Carbohydrates, necessity and sources

[strideknight]

Hey, So I've been a little confused and would appreciate some help if you wouldn't mind.

I've read everywhere about the importance of eating carbs to training, how your body utilizes it to restore glycogen, etc etc. Hell, I even do it myself - I eat ~ 125g/125g/250g c/f/p on rest days and ~300/110/250 on training days @ 325lbs, down from 400. On the other hand, I've read things like Gary Taubes' Good Calories, Bad Calories and Mark Sisson's books. While I don't agree with everything they say, they clearly have some well reasoned arguments, and Taubes' has a fair bit of science on his side.

I guess, where I'm getting confused is, what happens if you actually stuck to a LC (<50g/day) diet while trying to do SS? If you go into ketosis, will your body burn fat to replenish glycogen? That seems implausible to me. More likely it will convert protein into CHO in the liver and then send that out, right?

My other question is related... I get 95% of my CHO from Lactose/Fruit on rest days, and same on workout days except for a sweet potato and occasionally one of those tiny ice cream cups (hagen dazs chocolate peanut butter ftw). So, it's basically a 125g-175g fruitpocalypse come lifting days at my house. In one of your threads you mention that fructose isn't the best since its not broken down by skeletal muscle. Am I going to be sufficiently replenishing my glycogen or otherwise hindering myself by eating primarily fruit? I don't need the fastest gains in the world, I'd just like to get there.

Any advice would be fantastic! In fact, if you know of any good reading on the bio mechanical processes that go on, that is reliable (I used to feel my doctor's advice was reliable until I read Taubes), I would greatly appreciate it. I'm a science nerd by training, so more technical than less is always good too.

Thanks again,
Dave

[Jordan Feigenbaum]

I guess, where I'm getting confused is, what happens if you actually stuck to a LC (<50g/day) diet while trying to do SS? If you go into ketosis, will your body burn fat to replenish glycogen? That seems implausible to me. More likely it will convert protein into CHO in the liver and then send that out, right?

Your body will use all sorts of different substrates to make glucose in gluconeogenesis, i.e. lactate, amino acids, the glycerol backbone of a triacylgycerol (but not the fatty acid itself). Gluconeogenesis will proceed and replenish relevant glycogen stores, albeit very slowly. Depending on how high of volume or high intensity your training is (and how well you can run on ketones/fatty acids) this may be a problem for training or it may not.

My other question is related... I get 95% of my CHO from Lactose/Fruit on rest days, and same on workout days except for a sweet potato and occasionally one of those tiny ice cream cups (hagen dazs chocolate peanut butter ftw). So, it's basically a 125g-175g fruitpocalypse come lifting days at my house. In one of your threads you mention that fructose isn't the best since its not broken down by skeletal muscle. Am I going to be sufficiently replenishing my glycogen or otherwise hindering myself by eating primarily fruit? I don't need the fastest gains in the world, I'd just like to get there.

Well it is metabolized (or can be anyway) by skeletal muscle, just not at nearly the rate and load that the liver can handle. I don't particularly like super huge amounts of fruit for reasons I've stated elsewhere and if your fructose intake is really high, that may be hindering your gains. I'd lean more towards rice, potatoes, carb supplement, and oats if you're looking for performance.

Additionally, if you're number 1 goal is to just get lean, then going full on ketard with carloric accountability is probably your best bet with a refeed every 7-10 days or so on the order of 300-400g carbs.

Any advice would be fantastic! In fact, if you know of any good reading on the ..

I'd pick up Medical Biochemistry : Human Metabolism in Health and Disease as a nice primer. Also Advanced Nutrition and Human Metabolism is good too.

[strideknight]

Gluconeogenesis will proceed and replenish relevant glycogen stores, albeit very slowly.

So Gluconeogenesis will just keep going as long as there's glycogen to be restored? The more I learn, the more I'm impressed by the inherent functions of the human body.

... going full on ketard ...

Hahaha, oh man, you made my day. My primary goal is to keep developing strength and if my diet's right, the leaning will happen anyways. With that in mind, I'll probably keep my rest day fruits, but lower work day fruit and add some oats/rice.

Amazon is now winging the used (and astoundingly cheaper) versions my way. Thanks for the clarifications, I feel much less confused.

[Jordan Feigenbaum]

So Gluconeogenesis will just keep going as long as there's glycogen to be restored? The more I learn, the more I'm impressed by the inherent functions of the human body.

Well muscle glycogen doesn't make much a contribution to blood glucose, which must be maintained for various processes that are glucose dependent. So muscle glycogen is basically safe until you train, as resting muscles do not use glucose usually. At any rate, post training on a keto diet will produce some glucose that gets packed in muscle cells as glycogen, it just happens slower than dietary glucose would make it happen.

[Rezart Erindi]

then going full on ketard

Hah, quote of the month.

[Jordan Feigenbaum]

Hah, quote of the month.

Dave Palumbo would be soooo proud.

[Paul1]

Jordan,

You seem to differ but I am a pretty big proponent (for patients, not necessarily strength trainees) of eating fruit -- lots of it. The starches in fruit are highly complex, there is a very rich nutrient content, the glycemic index is low, the calorie content is low, the fiber content is high. The fructose in fruit is at a trivial level compared with sweetened foods (even peanut butter, which is sweetened, has more fructose than a typical fruit serving). Because of the glycemic index, the fiber content, and the water content fruit tends to be very satiating. This is a strongly evidence based diet approach for patients with "metabolic" disorders (by this I refer to the DMII / HTN / HL / visceral fat spectrum). And if you're substituting chemically simple carbohydrates (like corn syrup) with isocalorically complex stuff (a mix of berries, melons, bananas, etc) you're really biasing your body's hormonal response AGAINST insulin surges, visceral fat storage, etc.

So I can't really think of a reason, based in evidence at least, to discourage fruit -- unless it is part of a disordered eating pattern, which means that the fruit isn't really the problem.

[Jordan Feigenbaum]

The starches in fruit are highly complex, there is a very rich nutrient content, the glycemic index is low, the calorie content is low, the fiber content is high.

Let's use an apple (w/ a 100g serving size for the first example. There are 2.4g fiber, 13.3g of total sugar, 7.6g is fructose (monosaccharide), 3.3g are sucrose (disaccharide), and 2.3g are glucose (monosaccharide). The NLEA puts the average serving size at 242g, which yields us 33g carbs ( 18g of fructose) and 5.8g fiber. That's about an average fiber content (really low when compared to veggies actually) and has a significant amount of fructose.

The calorie count is meaningless, and total cereal has a higher nutrient content per calorie (except for k1 and vitamin C).

The fructose in fruit is at a trivial level compared with sweetened foods (even peanut butter, which is sweetened, has more fructose than a typical fruit serving).

Not true in apples, blackberries, cherries, grapes, kiwi, pears, pomegranates and dried fruits, etc.

Peanut butter may have up to 3g fructose per 100g. Not sure how this factors in to the argument that I don't like to recommend tons of fruit for anybody. Also, this is lower than apples, blueberrries, cherries, grapes, kiwis, pears, purple passion fruit's fructose content/ 100g.

Because of the glycemic index, the fiber content, and the water content fruit tends to be very satiating.

Glycemic index matters zero percent, period. The numbers are based on eating fasted with no other constituents in the meal, i.e. protein or fat. High GI, Low GI....it doesn't matter. Fiber is thermogenic, but the fiber content of fruit pales to vegetables. As for satiety, if we are assuming the satiety index is valid (I don't), then potatoes, meat, and oatmeal > fruit.

And if you're substituting chemically simple carbohydrates (like corn syrup) with isocalorically complex stuff (a mix of berries, melons, bananas, etc) you're really biasing your body's hormonal response AGAINST insulin surges, visceral fat storage, etc.

This is not true, unfortunately provided all other factors are equal, i.e. fiber content/carb total, protein levels, etc.

So I can't really think of a reason, based in evidence at least, to discourage fruit -- unless it is part of a disordered eating pattern, which means that the fruit isn't really the problem.

The reason is that fruit does a poor job of replenishing muscle glycogen, has some orixegenic compounds in it (fructose) that we know do bad things to people, and doesn't have anything proprietary that we can't get from veggies, quality meats, and starches.

I don't think fruit is awful for people, I just don't want someone to take in my recommended 200g of carbohydrates, for example, from fruit. I'd rather have them get 35g of fiber in and then eat whatever else they want.

If someone is not counting/weighing/measuring but eating ad libitum, I'd probably have them take a more low carb approach anyway, from a compliance perspective, and fruit wouldn't be staple or requirement of that approach either.

In summary, it's fine in small amounts, but it's not inherently healthy (unless it boosts compliance or is a positive feedback towards actual beneficial behaviors, like training) and could plausibly do some harm when people (as we often do) take it to an extreme.

[tzanghi]

Not to pile on Paul1, but I think it's important to remember that here, we're usually looking for optimal diet. For couch potatoes who exhibit the symptoms and disorders you speak of, lots of fruit is probably an improvement from potato chips and soda. I think Jordan is speaking towards what's optimal, with a strong tint towards physical performance, whereas you are talking about ways to improve from extremely poor diets for people who I would guess are rather sedentary. So I think lots of fruit could be beneficial for someone when it means replacing very poor choices, but overall, too much fruit is not that good. In this respect, I don't think you're too far off. Just my .02.

[subwindow]

I find fruit to be fantastic when I get a craving for something sweet. It's way healthier than a soda or sugary candy. Other than that, I don't find much use for them and maybe eat 1 serving a day on average.