by Mark Sisson: The
Definitive Guide to Grains
a big guy (okay, obese, if I’m being honest) who’s getting
smaller fast. I adopted the PB a couple weeks ago, and I’ve
already dropped twenty pounds, going from 300 to 280. Don’t
get me wrong, I’m not complaining. I’m just confused.
How does that work? You always hear that initial weight loss for
the really overweight is fast, but why? Is it really just water
weight? It seems metabolically impossible that I’ve actually
burned that much body fat… I can’t help but feel a bit
let down if all I’m doing is losing water. If there’s
one thing I learned from your writings, it’s weight isn’t
just weight (and calories aren’t just calories). So… what
the question, Todd.
common weight loss experience. You’re overweight. You decide
to take control of your health and shed some body fat. You go Primal,
drop a bunch of weight and the first thing you hear from detractors
is “Oh, it’s all water weight.” Uggh. How frustrating.
But it’s also absolutely true that the bulk of the initial
weight loss from a low-carb diet is from the expulsion of previously
retained water. The question is: is that loss of water necessarily
a bad thing? The answer is, as always, complex and we’ll need
to look at it in the context of all the changes taking place when
you start eating and exercising Primally.
people have accumulated their extra adipose (fat) tissue through
eating a diet that is higher in pro-inflammatory agents (insulin-promoters,
anti-nutrients and omega
6 fats) and generally also higher in sodium.
One of the side effects of such a diet is substantial water retention
both within the cells and in the spaces between cells (interstitial
space). This retained water can amount to 10, 20 or more pounds
depending on how large the person is. Even in non-obese people,
this effect often manifests itself most obviously in a “puffy”
look around the face or a feeling of “bloatiness.” It’s
a testament to the power of eating Primally when you realize that
often within just a week of decreasing grains
and other simple carbs and sugars,
as well as cutting omega 6s and the huge amounts of sodium found
in the SAD, the body no longer needs to hoard all this water. Understand
that this was water you never really needed in the first place;
it was just there because agents in the diet sent signals to different
systems to hold onto it. As long as you continue to eat
Primally, the need for this retained water ceases and you not
only weigh less, your body shrinks accordingly. Nothing wrong with
that as long as you retain muscle, which you do easily on a Primal
The other (albeit
secondary) source of rapid weight loss can happen in the muscles.
It’s also a short term adjustment to a decrease in carbohydrates
that – over time – levels out and soon becomes insignificant.
This is the idea that muscle glycogen is stored with water and when
you deplete glycogen, you deplete that water as well. You see, for
every gram of stored carbohydrate – also known as glycogen
to four grams of water are stored as well (PDF). So, if you
burn, say, 400 grams of glycogen through exercise without refueling
with carbohydrate in a short span of time, you might drop close
to a kilo of water, too. This can happen when a new Primal convert
gets overly enthusiastic and hammers the first few workouts. (Nothing
wrong with that, it’s just that we are looking to burn relatively
more fat than glycogen over the long haul.)
Why would the
body be “built” this way? It turns out that glycogen burning
releases water as a metabolic byproduct and that this fulfills an
athlete’s hydration needs.
it: glycolytic work, as a general rule, makes you thirsty. What
do hiking a steep mountain in the summer heat, going for a long
grueling bike ride, and running fifteen sprints to absolute exhaustion
have in common? They make you thirsty and they force you to burn
glycogen for energy. You see, in the real world, glucose demand
and hydration needs go hand in hand. You don’t engage in a
glycolytic activity without also increasing your requirement for
fluids. It appears as if your body stores water and glycogen together
because it “knows” that when you call upon the glycogen
for energy, you’re also going to be thirsty.