The Downside Of Carb-Cycling

The plain truth about this questionable practice

- Kat James

Readers have asked about a dietary concept that fat-burner enthusiasts refer to as “carb cycling”—occasionally or periodically reintroducing carbs into their diets. Achieving ketosis or leptin sensitivity (two states where the body is burning ketones, a byproduct of burning fat as one’s primary fuel) involves lots of individualization and trial and error. But the idea of planning weekly carb eating “cycles” is—at least from my decades of personal and observational experience— akin to a self-imposed slippery slope that people consistently regret.

Of course, if you never achieve a fat-burning state to begin with, carb-cycling is painless, because you’re not switching the body’s primary fuel, which always involves a degree of discomfort. But, for true insulin- and leptin-optimized fat-burners, fat is their body’s primary fuel. The minute a fat-burner starts eating dozens of carbs (and it takes much fewer carbs than most think to throw you out of a fat-burner state, especially if you’re metabolically challenged), the body will default immediately to the fat-storing, sugar-burning quagmire that many of us worked so hard to escape. That first spike in blood sugar signals the brain that you’re suddenly experiencing starvation as a default mechanism of cutting off sensitivity to the hormone leptin in the hypothalamus.