Using a low-calorie diet and exercise to lose weight will work for a while. At some point, you might hit a wall and then you'll need to adjust your plan to keep the results coming. If you don't, you can get stuck and lose your motivation.
Weight loss can be a long and tedious journey. Ideally, your weight will just steadily decline until you're happy with the results, but the reality is that you'll probably have ups and downs along the road.
Metabolic adaptation occurs when you lose a significant amount of weight. It means your body is using fewer calories, so you need to do more exercise and decrease calories even further to keep seeing progress.
Weight Loss Is Never Easy
If you've had good results for a while with your diet and exercise routine but found that they've stopped working, you may need to adjust some things. Understanding how fat loss works will offer some insight into why your progress ground to a halt.
An April 2016 paper published in Frontiers in Endocrinology provides an overview of fat cells, also known as adipose tissue. When you're in a caloric surplus, your body stores certain nutrients in fat cells. It also makes new fat cells that don't go away when you lose weight — they simply get smaller.
As you lose weight, your body reacts stubbornly. It releases hormones that make you more hungry and less motivated to exercise. The number of calories you burn at rest and during exercise drops, according to a small study published in Nutricion Hospitalaria in June 2015.
Since your body is fighting to preserve energy, there are two obstacles you'll face when you want to drop pounds: losing weight and keeping it off. Your initial drop in weight may be easier than maintaining the results over time. That's because your metabolism slowly adapts to a low-calorie diet and exercise.
Why Your Body Adapts
A May 2018 research paper published in the journal Obesity explains the problem of metabolic adaptation. Researchers were interested in what happens six months to a year or more after weight loss. They noticed that in most cases, metabolism adjusted to the new weight for a year or more.
To understand these findings, it's important to know how your metabolism works. The human body requires a lot of energy to function normally every day. Your energy expenditure at rest is called resting metabolic rate. The bulk of that energy goes to organs like your brain and heart and can be used for tissue repair and maintenance, among other functions.
According to the National Academy of Sports Medicine, your resting metabolic rate makes up about 60 to 75 percent of the energy you expend every day. The rest comes from activity. When you lose weight, your resting metabolic rate goes down. At the same time, your body adapts to exercise and begins to use less energy.
To find out how many calories you're truly burning from exercise, you can use a "calories burned" calculator. As you lose weight, your body burns fewer and fewer calories per day, so you need to tweak your diet and workout routine to prevent plateaus.
Read more: List of Low-Carb & Low-Calorie Foods
Low-Calorie Diet and Exercise
While there's not much you can do to prevent your metabolism from slowing down, you can use diet and exercise to maintain and even continue your weight loss. Reverse dieting is another technique that can help.
Since your energy expenditure is low after weight loss, you can slowly increase your calorie intake to boost your metabolism. Reverse dieting is promising, according to a February 2014 review published in the Journal of the International Society of Sports Nutrition. However, more research is needed in this field to confirm the benefits.
The review suggests that you should stick to your exercise routine even if your weight loss has slowed or stopped because it can help you maintain your results. You might want to consider adding a third element: cognitive behavioral therapy. It can round out your diet and exercise plan.
A January 2018 study published in Enfermeria Clinica has found that subjects who combined diet, exercise and cognitive behavioral therapy had the best results. If you don't have the time or resources to go to a therapist, you may want to consider online interventions, which are accessible and more cost-effective.
- Enfermeria Clinica: "Overweight and Obesity: Effectiveness of Interventions in Adults"
- National Academy of Sports Medicine: "Resting Metabolic Rate: How to Calculate and Improve Yours"
- Obesity: "Metabolic Adaptations to Weight Loss"
- Frontiers in Endocrinology: "Adipose Tissue Remodeling: Its Role in Energy Metabolism and Metabolic Disorders"
- Nutricion Hospitalaria: "Effect of Calorie Restriction on Energy Expenditure in Overweight and Obese Adult Women."
- Journal of the International Society of Sports Nutrition: "Metabolic Adaptation to Weight Loss: Implications for the Athlete"