Here's the deal: When you read or hear about this concept, it's usually because someone is trying to explain why dramatically cutting calories to lose weight is a bad idea. The starvation mode theory holds that crash-dieting isn't just dangerous, but it's also counterproductive. You're trying to lose weight, but you're actually slowing down your metabolism, which makes it even harder to accomplish your goals! Unfortunately, the idea that crash-dieting will slow your metabolism, while well intentioned, isn't really an accurate read of the science. I'll talk about why in more detail. But also, something else I'm going to talk about: Crash-dieting or yo-yo dieting or dramatically cutting calories for the sake of weight loss is definitely still a bad idea, and also counterproductive. Just…not because of the metabolism thing. Let's get into it.
The concept of starvation mode is confusing because, yes, it is a thing—if you don’t eat enough, in response to the low intake of fuel, your body will likely store calories it would otherwise burn. But starvation mode isn’t an ever-present threat lurking around every corner, just waiting for you to skip a meal so it can kick into gear and mess with your metabolism.
“A lot of times people think they’re going into starvation mode when they skip a meal or fast for a day, and that’s truly not the case,” Philadelphia-based Joy Dubost, Ph.D., R.D., tells SELF. Unless someone has a prolonged, dire lack of access to food or an eating disorder like anorexia, it’s very hard to go into what Dubost describes as “complete clinical starvation mode.”
Rachele Pojednic, Ph.D., assistant professor in the nutrition department at Simmons College and staff scientist at Beth Israel Deaconess Medical Center, agrees. “There’s a difference between the popular perception of starvation mode with regard to diet culture and actually being starving,” she tells SELF.
When a person has been eating a low-calorie diet for long enough to actually be starving—there’s no specific caloric threshold or length of time for this to happen because it’s so individual, the experts explain, but it certainly takes longer than a day without food—a few physiological processes take place.
For starters, your insulin and glucose levels can get thrown out of whack. Insulin is a hormone that shuttles glucose (blood sugar) from the bloodstream into the body's cells, where's it's stored as glycogen for later use as energy. When insulin is low, that keeps the glucose in your blood. This happens in the case of starvation so that you have more blood glucose available for quick energy, Pojednic explains. Your body will also start to increase a process known as lipolysis, or breaking down fat to release fatty acids for energy. In addition, you’ll break down protein reserves, usually muscle, for another energy source, Dubost explains, and undergo large mineral losses that affect your body’s electrical systems, like your heart. Symptoms of all of this can include weakness, apathy, memory lapses, and muscle cramps.
“It’s really hard, if you have adequate access to food, to put yourself into this mode because you are always going to be able to eat something eventually,” Pojednic says.
Read More Of This Article Here: "Starvation Mode" Takes Some Time to Go Into Effect, Experts Say | SELF