A sustainable calorie deficit is the only direct cause of weight loss, and hormones, stress, sleep, and routines mainly influence appetite, energy, water retention, and eating behavior. Many people with excess weight put in a lot of effort, but methods that are too strict often lead to the opposite result.
Adelina Vishneva explains why the number on the scale may not go down, whether cortisol is to blame, and whether sugar has to be excluded. Adelina Vishneva is a pediatric endocrinologist, dietitian, and nutrition specialist.
The short version
- Excess weight is caused by a calorie surplus, and hormones do not create body fat out of nothing.
- Stress and lack of sleep can change appetite and eating behavior, but stress and lack of sleep do not cancel the role of total calorie intake.
- A moderate calorie deficit is more sustainable than a harsh diet, and a balanced meal is usually more filling than foods with the same calories but less substance.
- Weight loss is not linear, and day-to-day changes of 1 to 1.5 kg are often water rather than fat.
- Long-term results usually come from gradual changes, not bans, crash diets, or trying to do everything at once.
What causes excess weight: cortisol, insulin, or thyroid problems?
Excess weight is caused by a calorie surplus. Cortisol, insulin, and thyroid problems are often blamed, but in most cases they are not the reason body weight increases.
Hormones can affect appetite, swelling, energy levels, and fat distribution in the body, but hormones do not create extra fat out of nothing. Terms like a “cortisol belly” or “cortisol face” are not diagnoses.
High cortisol does occur in medical conditions such as Cushing's disease and Cushing's syndrome, but those conditions are treated by endocrinologists. Supplements and fasting days are not the treatment for those conditions.
Many myths also surround insulin. Excess weight leads to high insulin and a disturbed metabolic response to insulin, rather than insulin causing excess weight, and a person in a calorie deficit will lose weight.
Why do some people lose weight during stress while others gain weight?
Excess weight always comes back to a calorie surplus, but the reasons for that surplus differ from person to person. Obesity is a multifactorial chronic condition, and sleep, stress, and overall wellbeing affect eating behavior.
Stress can increase cravings for sweets in some people and can contribute to fluid retention that people often call swelling. Stress can also lead to a calorie surplus and weight gain.
Some people eat their emotions, while others skip meals during stress. Eating behavior during stress is individual.
Do you need to eat more to lose weight?
A calorie deficit does not mean eating very little. Calorie intake needs to be appropriate for the person.
If a person usually eats 3000 kcal per day and cuts straight to 1500 kcal, that approach is not the best strategy for long-term results. A deficit of 7% to 10% would give 2790 to 2700 kcal, and that amount can still allow a varied, satisfying, and comfortable diet for that period.
Calories are not the same as food volume. Foods have different nutrient density, and a balanced meal with protein, fat, carbohydrates, and fiber can contain 500 kcal while being much more filling than a pastry with the same 500 kcal.
Harsh calorie restriction often leads to breakdowns because the eating pattern becomes too hard to maintain. Slow work on eating habits, enough food, more activity when possible, and strength training when suitable are presented as a better path.
Are there people who can never lose weight?
There are no hopeless cases physiologically, because weight decreases with a stable calorie deficit. In practice, progress depends on readiness to make changes.
Working with excess weight is hard, long, and repetitive. Small steps can still bring large results.
If a person asks for help but refuses every recommendation, then help is unlikely to work at that stage. Readiness for change matters.
Why has weight loss stopped?
Weight loss is usually wave-like rather than linear. The number on the scale reflects not only fat, but also muscle, water, and bone.
Body weight is also affected by what was eaten the day before, whether there was exercise, how much walking happened, and how much sleep happened. Fluctuations of 1 to 1.5 kg are often water, and that is normal.
About 7500 kcal are needed to create 1 kg of fat. Monthly weigh-ins, body measurements, and photos can therefore be more useful than daily weighing.
A person may still be losing fat while the scale stays the same for a while because of fluid retention. If there are doubts about progress, consulting a specialist is recommended.
How fast should healthy weight loss be?
The pace of weight loss depends on the starting point. Body weight, current diet, relationship with food, and a history of disordered eating all influence the process.
Promises of minus 10 kg in a month create unrealistic expectations. When a person loses “only” 2 kg in the same time, disappointment often follows, even though rapid-loss experiments and starvation are usually followed by equally rapid regain.
Chasing a number is less useful than looking at overall direction. One month may bring 1 kg of loss, another 3 kg, and another 500 g.
What should you do when motivation disappears?
Motivation often disappears when a person starts too radically. Plans like going to the gym 3 times a week from tomorrow, starting a strict diet on Monday, cutting out sugar completely, and eating only homemade food usually become exhausting after 2 to 3 weeks.
Gradual changes are more realistic and more sustainable. A person who does not like cooking does not need to force long cooking sessions and can instead learn to choose suitable dishes in cafés and shops.
A person who does not like running does not need to start running for weight loss. Temporary methods usually bring temporary effects, so a useful question is whether the routine could be followed for life.
What mistakes are most common during weight loss?
The most common mistake is expecting a fast result, not seeing it, and giving up. A lapse or setback then leads many people to think weight loss is impossible for them.
Weight loss is a long process, and slower, lasting progress is better than fast, ineffective progress. Enjoyment matters because a more pleasant process is easier to maintain.
The article advises letting go of diets, excluding foods, doing sport 7 days a week for weight loss, avoiding cafés and restaurants, and fasting. Setbacks and overeating episodes can happen, and the important step is to continue rather than quit.
Weight loss requires patience and consistency rather than a perfect diet and a perfect routine. Even a week of overeating within several months of calorie deficit does not erase the whole result.
Plate method or calorie counting?
Both methods can work, and the better method is the one that suits the person. Adelina Vishneva personally prefers the plate method.
Calorie counting often creates anxiety because many people are tired of counting. Calorie counting can also weaken connection with the body because the focus shifts from hunger and fullness cues to specific numbers.
Each day is different from the last, so the amount of energy needed from food also changes from day to day. The plate method is presented as a more comfortable tool for many people.
Can you eat anything and still lose weight?
You can lose weight while eating different foods, but quantity and regularity matter. The first step is to set up a basic eating pattern.
A basic eating pattern includes balanced, tasty, filling meals, an adequate amount of food, and work on emotional hunger. When those foundations are in place, cravings for “unhealthy” foods usually decrease.
Weight loss does not require a calorie deficit every single day. A packet of chips, cake, or a feast from time to time does not prevent weight loss if a person stays in a calorie deficit about 85% of the time.
What 5 recommendations support comfortable weight loss?
The first recommendation is to remember that weight loss is not the main business of life. Weight loss should fit into life without putting all other processes on pause.
The second recommendation is to work with the cause of weight gain, including eating behavior, hunger and fullness, and meal routine. The article stresses the importance of understanding a person's life rather than simply saying “eat less and move more,” and often the recommendation is actually to eat more.
The third recommendation is not to ban any foods because bans often lead to overeating. The fourth recommendation is to eat sweets that bring pleasure rather than sweets chosen only because they are considered “healthy.”
The fifth recommendation is to always keep food at home for times when cooking is not possible. Planning is described as 50% of success and of lowering the risk of overeating.
What should you bring to an endocrinologist appointment for weight loss?
A food diary is the most effective and most informative thing for a doctor working with body weight. The more detailed and honest the record is about time, portion size, hunger, fullness, and emotions, the better.
The person and the complaints come first, and tests come later if needed. In obesity, basic tests that can be brought to rule out complications include a complete blood count and ferritin, glucose and HbA1c, AST and ALT, a lipid profile, and TSH.
Other tests depend on the situation. The most important thing to bring is an honest story about yourself and your relationship with food.
Common questions
Is insulin resistance the reason I cannot lose weight?
The article says insulin resistance is more often a consequence of excess weight than its cause. The article also says weight will go down in a calorie deficit.
Does high cortisol cause a cortisol belly?
The article says “cortisol belly” is not a diagnosis. The article also says genuinely high cortisol belongs to medical conditions treated by endocrinologists.
Why does my weight change by 1 to 1.5 kg so quickly?
The article says daily changes of 1 to 1.5 kg are often water. Food, exercise, walking, and sleep can all shift scale weight without reflecting a real gain of body fat.
Should I weigh myself every day when trying to lose weight?
The article suggests weighing, taking measurements, and photos once a month rather than every day. Monthly tracking can make normal water fluctuations less discouraging.
Do I have to give up sugar to lose weight?
The article does not recommend banning foods, including sweets. The article says bans often lead to overeating and that enjoyable sweets can still have a place in the diet.
What is most useful to bring to a first doctor visit about weight loss?
The article says a detailed and honest food diary is the most useful starting point. The article also lists basic tests that may be helpful in obesity, but says the person and the complaints come first.