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?


Metabolic Pathways while fasted and Ketosis

Was just commenting on Patri Friedman’s livejournal (here) regarding how the metabolic channels used while fasting were the same as those used while on a low-carb diet. Taubes notes fact in passing in Good Calories, Bad Calories but since that’s a hard reference to check on the ‘net, here’s another bit of support from Dr. Mike Eades of Protein Power:

If you read any medical school biochemistry textbook, you’ll find a section devoted to what happens metabolically during starvation. If you read these sections with a knowing eye, you’ll realize that everything discussed as happening during starvation happens during carbohydrate restriction as well. There have been a few papers published recently showing the same thing: the metabolism of carb restriction = the metabolism of starvation. I would maintain, however, based on my study of the Paleolithic diet that starvation and carb restriction are simply the polar ends of a continuum, and that carb restriction was the norm for most of our existence as upright walking beings on this planet, making the metabolism of what biochemistry textbook authors call starvation the ‘normal’ metabolism.

As noted before, this makes intuitive sense. While in a fasted state, the body gets its energy fix by robbing the protein for gluconeogenesis from lean tissue and the fat for energy from adipose tissue. While doing low-carb, the body does the same thing — the only difference is that it gets the fat and protein from dietary sources.

The rest of the Eades article discusses ketones/ketosis, which I’m still working on fully understanding (the basics, anyway). Apparently there are other benefits to occasionally being in a ketogenic state that may include “de-junking” our cells. Neat!