Understanding Bodyweight and Glycogen Depletion

If you are dieting or are planning to start a diet, you need to understand the connection between bodyweight and glycogen, that is how carbohydrates get stored in your liver and muscles, so you don’t overestimate your weight loss as you cut carbs—or your weight gain if you add some back. Understand the connection and you’ll have a much better chance of keeping your cool for the long-haul when swings inevitably happen.

So what exactly is going on?

Mark Sisson: a Contrarian View on Water

A contrarian by nature (Perhaps to a fault), I found Mark Sisson’s recent counter-conventional post on water well worth the read. Bucking the mainstream view that we should drink at least eight glasses (64 oz. total) of water per day, Mark exhaustively details the counterpoint, advocating what seems downright obvious: obey your thirst!

Some takeaways from Mark’s post:

  • We get a lot of water from our food. Mark argues that paleolithic man likely recieved most of his water from food sources. Example: eating fruit will help satisfy your body’s water requirements.
  • Diuretics like coffee, tea and alcohol necessarily contain water, and the diuretic effect only occurs at high, unhealthy doses.
  • Drinking a lot of water before or during a meal can thwart digestion by raising pH levels in your stomach. Raised pH levels can result in indigestion or worse: lowered acidity could reduce the stomach’s ability to destroy susceptible pathogens and other creepy crawlers!
  • The commonly-held mantra that thirst lags dehydration (i.e. “if you’re thirsty, you’re already dehydrated”) is erroneous. Therefore, as one sugary drink prescribes, “Obey your thirst!” with H2O.

Mark packs a lot more into his post, so be sure to read it.

On a related, technical note, in Good Calories, Bad Calories Gary Taubes explains how carbohydrates induce water retention (Fats do not). Assuming I recall correctly, a fat gram has two times the amount of energy as a carbohydrate gram (9 kcal compared to 4). Furthermore, storing a carb gram requires two grams of water. Therefore, energy equivalence between fat and carbohydrates from a volume standpoint is reached at 1:6 fat to carb/water ratio as follows:

1 gm fat = 9 kcal @ 1 gram volume
2 gm carbohydrate + 4 gm water = 8kcal @ 6 grams volume

Thus we see the efficiency of fat as an energy storage vehicle — a whopping 6x as much energy can be stored in the body as fat relative to the volume it would take to store the same amount of energy with carbohydrates!

Between Mark’s comments and Taubes fat-storage efficiency explanation (Would love an online reference here if anyone can find one), I have to wonder: does a low-carb diet go hand-in-hand with lowered water requirements? At first blush, it seems like the answer would be a resounding yes, but I don’t know. Readers?