Mauricio:

Yogurt and fruit have a lot of sugar, not starch.  Sugar is half fructose, which doesn't help replenish your muscle glycogen — only glucose can do that.  And, frankly, it's difficult to choke down enough sweet potatoes to make up for intense exercise.

Since sport climbing is intense and heavily glycolytic, the odds are that you're simply not getting enough starch in your diet.  Try adding white rice (rice noodles are great, too) and white potatoes…the variety is often sufficient to give you enough appetite to eat enough.

If you're still hurting, buy some Sweet-Tarts, Bottle Caps, Runts, or Spree candies, which are basically 100% dextrose with impurities and food coloring (and much cheaper than the equivalent in "energy goop").

If your cravings are for carby/sugary junk, I suspect they'll go away after eating more starch.  But if you still need something sweet and dessert-ish, I like a square or two of dark chocolate.  And every once in a while I'll drink an energy drink or a Coke, or eat a Reese's, for dessert.  Occasional cheating won't kill you, and nothing will ever make a Reese's not taste good.  The key is to eat them after a meal, when you're already full.

Let me know how this works for you!

JS

Mauricio:

Make sure to check back and let us know how you're doing.

JS

Mauricio:

Absolutely.  If eating potatoes and rice stops your desire to eat candy, then your problem is glycogen depletion.

This observation segues nicely into your next paragraph.  Controlled study after controlled study proves that all weight-loss diets work if you physically force people to stick to them (e.g. by locking them in a hospital ward).  In the real world, the results of a diet depend on how difficult it is to stay on the diet.  

It turns out that we already know the results of a so-called "low-reward diet": it's the standard low-fat, high-carb, whole-grain "healthy diet" pushed on us for decades!  Piles of beans and brown rice; heavy, tough whole-grain breads; no added fats, oils, or sugars, and especially no salt...everything we're supposed to do according to the McGovern Report (eat less meat and eggs, eat less animal fat, eat less salt, eat less refined grains, eat more whole grains) makes food less appealing.

We all know the results: America has become steadily fatter and sicker since adopting this as our official, government-sanctioned dietary model back in 1978.  So the evidence is clear: compliance with "low-reward diets" is low.

Since compliance is the biggest problem, I think a successful diet should be based on the most delicious foods possible -- thus reducing the temptation to "cheat".  (This is because -- as I've explained at length -- satiety is primarily nutritionally driven, and satiation is primarily driven by the sensory experience of eating.)  However, the most important constraint is that the foods must be as nutrient-dense as possible, because everything flows downhill from satiety, and (again) satiety is nutritionally driven.  

Therefore, my preferred strategy is to eat the most nutrient-dense foods possible, and to make them as delicious as I can!

Moving on: I don't even like to use the term "food reward", because it's misleading: "reward" is the product of multiple motivations, most of which have little or nothing to do with the food itself!  Saying that overeating is caused by "food reward" is like saying alcoholism is caused by "alcohol reward": we haven't said anything.  All we've done is restated the problem in a way that makes us sound smart.

Therefore, foods do not have a property called "reward".  Foods have hedonic impact, popularly known as "palatability", they produce satiation and satiety -- and all these factors are altered by previous experience, and by cultural and social context, as well as by the taste, nutrients, and preparation of the food.  The product of all these factors is "incentive salience" -- the drive to actually consume more of a food.  Calling this product "food reward" is wrong because it implies that it's solely a property of the food itself.  (See my Oreo example from Part VII.)  

Regarding dopamine response, the oversimplification of the science by the popular press has you confused.  Any food with hedonic impact (i.e. any food you "like") produces a dopamine response and a "want" for more.  Furthermore, this isn't limited to food: any experience we like, from meeting friends to winning a game, produces a dopamine response!  EVERYONE FREAK OUT

I hope these explanations help clarify the issues for you.

JS