You may have heard that cutting calories is one way to lose weight, but one must be careful, lest they cut too many calories and drop the body into “starvation” mode and gain the weight back.
This is partly true.
Starvation is a thing that happens to those that do not have access to food and not enough fat stores to live on. If you are overweight or obese and trying to drop a few pounds, true starvation is not a concern for you. “Starvation” mode is a serious misnomer.
If a person is trying to lose weight, barring any thyroid or hormonal abnormalities, the formula is simple. One must burn more calories (energy) than they take in. If they take in more calories (energy) than they burn, the body will store these excess calories in the form of fat and the person will gain weight.
But the body is smart. And thousands of years of evolution have created a handy adaptation for humans. Since the beginning of time, people were constantly going through periods of feast and famine. During feast times, we stored fat to prepare for times of famine. During famine of unknown length, the body learned to SLOW DOWN how fast it burns calories (energy).
The body burns energy (metabolizes) in four different ways:
- Exercise (any conscious movement)
- Basal Metabolic Rate (the calories it takes to keep the brain functioning, heart beating, etc.)
- Thermal effect of food (digestion usually burns about 10% of the calories consumed)
- Non-exercise activity thermogenesis (fidgeting, shifting in your seat, bouncing your knee, other subconscious movement)
The body has control over how much energy it uses to do all of those processes. It can do this by discouraging a person from moving, by making a person so hungry that they eat anything and (in the case of our modern society) everything, or by actively slowing down metabolism. When calories are restricted long term, the body can drop how many calories it uses to do all of the above processes by 10-25%. This is why weight loss may start off quickly and then slow down as time goes on with any diet/exercise program.
The body does this to keep us alive, because our hardwiring doesn’t know that we live in a world where food is almost always available for little to no work.
A metabolic slowdown could cause a person to gain weight. If the energy needed for the body to stay alive drops, but the person is still eating a strict diet of a certain number of calories, then suddenly their calories in exceed calories out. Consequently, the person stops losing or even gains weight.
There are a few ways one can stop this process of metabolic slow down.
- Lift weights (studies show that people who do resistance training-not cardio-maintain or increase their muscle mass, which is important to keeping the basal metabolic rate high, even on highly calorie-restrictive diets.)
- Eat lots of protein-high protein intake can reduce appetite and boost metabolism.
- Refeed-taking a break from a diet for a few days to a few weeks can reset the hunger and thyroid hormones. It is important to not go hog wild on a refeed. Eat at or just above a maintenance level of calories to not undo all the progress.
“Starvation mode,” in reference to weight loss, is a misnomer and should be referred to as metabolic slow down. This happens when one restricts calories for a long time, and could cause a diet to stop working. There are a few ways that one can combat the effects of a metabolic slow down. But without this genetic adaptation, humans would have been extinct thousands of years ago.