Low-Carb Energy Crisis
I recently posted a blog refuting the facts stated in an article on The Huffington Post by Sarah Klein, Senior Editor, Health & Fitness and a Certified Personal Trainer, titled the “5 Signs You Should Be Eating More Carbs”.
However, I felt I needed to better address Klein’s assertion that “When physically active people don’t get enough carbs, the body can resort to using protein for necessary muscle function, including muscle building, which is why carbs are often called ‘protein sparing’.”
This statement is so patently false and misleading that even I, who am not a Senior Editor in Health & Fitness or a Certified Personal Trainer, can see it for what it is – bullshit.
Your body turns to protein (i.e. muscle tissue) as an energy source only as a last resort. It’s the step your body takes, usually when you’re in deep starvation mode, just prior to deciding that your own liver and kidneys would be enjoyable with a side of fava beans and a nice chanti.
The bottom line, however, is that you’ve got to get to a point where your body is forced to use protein before it actually does use it. This commonly happens when someone tries to follow a low-carb diet and restrict their caloric intake at the same time. This ill-advised approach tricks your body into starvation mode and it reacts accordingly – slowing down your metabolism, discouraging you from expending energy (you don’t feel like moving) and generally wreaking havoc on the delicate system of hormones that regulate metabolism and adiposity. You’re very likely to lose some muscle mass in this scenario.
Then why do low-carbers seem to lose weight effortlessly and maintain their muscle mass?
Let’s do a little science and math here (I can hear you groan). Let’s assume that a pound of fat is comprised of roughly 3,500 calories. It’s not, for reasons so eloquently elucidated by Zoë Harcomb here, but let’s just say it is for argument’s sake. If you’re at all like me, you have at least 10 or more pounds of body fat to lose (as determined by caliper measures or hydrostatically). That means that at any time, I have at least 35,000 calories of available energy stored in my visceral area just waiting for a signal to be sent to my muscles to be burned as energy (or otherwise metabolized by my as-yet-to-be-auto-cannibalized liver). If the “average” daily calorie intake for someone of my height, weight and activity level is 2,200 calories I have at least 15 days of energy available before my body needs to tap my muscle tissue for protein.
Additionally, my daily calorie intake often exceeds 2000 calories; including at least 40%-50% of said calories from calorie-dense fat and another 40%-50% from protein (<10% of my total daily calories come from carbs). So between the calories I’m eating and the calories I already have stored in really unattractive ways in my body (like the layer of adipose over my undoubted six-pack), I’m not at any risk of running out of available caloric energy anytime soon. I consume more than enough protein to maintain my muscle mass (and probably grow it, should I ever decide to start serious resistance training).
If anything, my problem is I consume too many calories and have too much excess protein. This sometimes hampers my weight loss (but doesn’t increase my weight for reasons covered here) and can lead to oxidative stress caused by all the “exhaust” released as my mitochondria burn through my excess energy. Lower calorie consumption = lower oxidative stress.
So, gentle reader, don’t fear the specter of low-carb eating causing muscle loss. If you take in sufficient calories and include ample amounts of protein, there should be no measurable muscle loss. However, you should definitely fear wherever Sarah Klein is getting her facts from, as the source is questionable, at best.