Holy weight loss, Batman!
Spend enough time scrolling through keto-diet or weight-loss Reddit threads and you’re bound to come across the “whoosh” — an effect that many dieters explain as a sudden but significant drop in pounds.
Doctors and nutrition experts have debunked the concept before, though the whoosh effect is not altogether flim-flam. Still, dieting with the goal of rapid weight loss is rarely healthy, and protocols advocating for it should be taken with more than a grain of salt.
The ketogenic diet, known by the shorthand keto, has been used in health care settings for over a century. But it reached peak fad status in the internet age, as bloggers lured people with the siren-call of a diet that demands all-you-can-eat bacon.
Keto — a high-fat, low-carb regimen — was originally prescribed to patients dealing with epilepsy, because of how it can help stabilize neurons in the brain over time and prevent seizures.
With strict adherence, the diet induces a biological process known as ketosis, training your body to run on fat instead of its normal fuel of carbohydrates like glucose and other sugars.
Cutting out carbs (breads and pastas but also certain fruits and vegetables) and replacing them with high-fat foods like meats, fish, dairy and oils gives the body no choice but to burn fat for energy instead.
The diet’s mystical status rose even higher when people online began chatting about the supposed “whoosh effect” and the immediacy of the diet’s results in the mirror.
“The point of talking about a whoosh is so that people aren’t discouraged when they see the scale stuck for a couple weeks,” one Redditor wrote in a weight-loss thread. “And then you may see a big drop overnight, because your body expels the water weight it was holding onto, and now your real weight shows.”
Another commenter wrote: “I explain a ‘woosh’ as my body feeling safe enough to drop some weight. It holds on, makes sure that the deficit is a pattern of new behavior and not a fluke and then seems to be like ‘cool, we are not in danger. Feel free to let this go.’”
But experts see it differently.
Registered dietitian Gregory Lafortune, MS, RDN, LD, tells The Post that the whoosh effect is a “real experience, but it is often misunderstood.”
“People see it as a sudden fat loss from being on the keto diet,” he explains. “Instead, the whoosh effect is attributed to shifts in water weight due to the keto diet. It’s not a sudden loss of fat. It’s a sudden loss of water weight. Fat loss is gradual.”
The purge in water weight might be more pronounced on the keto diet because of how the body stores carbs.
It’s right there in the name: Carbo-hydra-tes. They’re stored in the body as glycogen, a constellation of glucose molecules. For every gram of glycogen stored, there’s at least three grams of water cached away with it.
“This is why someone on a low-carbohydrate keto diet loses water weight,” Lafortune says. “This differs from other diets because they may not restrict carbs as strictly as keto does.”
Rapid weight loss can indeed occur from a very low carb diet, often within the first few days. But it’s water weight, not fat, as some champions of the whoosh effect claim.
Chasing the whoosh effect isn’t just a lost cause, it can also lead to serious issues like dehydration.
Some keto dieters talk about diarrhea — which can dehydrate the body and strip it of important nutrients — as a sign that they’ve achieved the whoosh effect.
Some say they’ve triggered the whoosh by other harmful means like yo-yoing between fasting and binging or drinking alcohol for diuretic effects.
According to Healthline, “each of these approaches is aimed at dehydrating your body. While it may make you feel temporarily thinner, it’s not a lasting effect.”
In general, Lafortune recommends setting goals that prioritize long-term health, not just immediate changes in the mirror.
If GLP-1 fever has taught us anything, it’s that rapid weight loss can do real harm to the body.
Whether it’s from a diet like keto, a medication like a GLP-1 or another source, Lafortune counts muscle loss, higher risk of regaining weight, slower metabolism, overall loss of strength and energy and sometimes severe nutrient deficiency as potential side effects of rapid weight loss.
Suffice it to say, the whoosh effect isn’t the overnight miracle some people make it out to be. Crash, bam, kaboom.
