What Is “Starvation Mode”?
Q: What is starvation mode? From what I’ve heard, it’s something you should avoid entering into like marriage and Alcoholics Anonymous!
A: To lose weight, you have to be in a negative energy balance, or calorie deficit. Weight loss takes place only when that calorie deficit is created by consuming less food to reduce calorie intake or more exercise is performed to increase calorie burn, if not a combination of both. Starvation mode is a type of metabolic adaptation where weight loss doesn’t occur even in the presence of the required calorie deficit.
When the body is in starvation mode, weight loss slows down and comes to a screeching halt instead of continuing at the rate it was enjoyed at. In fact, you might actually gain weight instead of losing it. The onset of starvation mode is said to be brought on by too large of a calorie deficit, which results in the detailed series of events that are part of the body’s survival response in the face of too few calories to meet its energy needs.
Rather than the body tapping into its fat stores or burning calories from incoming food as it normally would during a moderately sized deficit, a deficit that’s too aggressive is said to prompt the body to hoard energy in protection of itself because it believes it’s starving and has to preserve energy to perform its vital functions necessary to remain alive. That’s essentially the idea behind starvation mode and why weight loss stops and it’s possible to gain weight when you enter it.
On the surface, starvation mode sounds like an actual thing, right? It sure does…
…but that’s only if you live in a fantasy world where anorexics, famine survivors, Holocaust prisoners, and participants in the Minnesota Starvation Experiment have never existed.1In 1944, researchers at the University of Minnesota fed 36 young, healthy men half of their normal calorie intake while having them engage in daily physical work and walk 22 miles per week. At the end of 6 months, all of the men lost 25 percent of their starting body weight while their basal metabolic rates experienced at least a 40 percent decrease from their respective baselines. The significance of the latter is explained further in the reading. In this real world that we’re inhabitants of, starvation mode for some reason doesn’t appear to have prevented those people with extreme calorie deficits from losing weight to the point of emaciation.
As anyone who’s ever tried to lose weight knows from personal experience, weight loss does slow down and might eventually stop altogether regardless of the deficit size. That, however, isn’t because of starvation mode. No, as long as you’re in a calorie deficit, you’ll always burn enough calories to lose weight and will continue to do so until you die from malnutrition and the body breaking down its own tissue for energy.
The body always loses weight in the presence of a calorie deficit. The only thing that will change during weight loss is the speed in which you lose weight because of a metabolic adaptation known as “adaptive thermogenesis”, which is when the metabolic rate decreases because the body becomes more efficient at operating on fewer calories in response to changes in increased physical activity and/or decreased food intake.2According to the findings of a study in the International Journal of Obesity, a 10 percent reduction of body weight is associated with a 20-25 percent drop in total energy expenditure.
Due to the adaptive thermogenesis that occurs to the metabolism with a change in the input and output of calories during a deficit, weight loss slows down but never to the point that it completely stops. When it happens that you stop losing weight entirely, that means that there isn’t actually a deficit and fewer calories need to be consumed or more exercise performed, if not some other remedy. Either that, or several hormones associated with weight control are out of whack because of poor sleep or unresolved stress, as well as certain health conditions or prescribed medications. It’s only under those circumstances can someone who’s actively trying to lose weight go from losing it to weight loss suddenly stopping and the lost weight possibly getting regained.
The concept of starvation mode is a poor understanding of what actually happens when you lose weight. So being that it’s not real, it’s not something that you should worry about entering. As for being asked to essentially give up having fun, that’s a very real thing so you absolutely should avoid entering marriage and Alcoholics Anonymous!
Now, does anyone else have a fitness or nutrition question of their own that they want to ask?
Glossary: caloric deficit, calories, exercise, fat, fitness, food, hormones, metabolism, nutrition
- Just The Tip #4441 - May 5, 2026
- Just The Tip #400 - May 4, 2026
- Just The Tip #3017 - April 30, 2026
