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Everyone knows that. One day you jump on the scales and thanks to the number on the display you feel good about yourself and then the whole day is somehow more sunny and you feel really good. A day or two after that, you want to make sure you’re still doing so well. You step on the scale and hope that the number on the display will be even smaller. A moment of tension … “Well, are you freaking kidding me?” The scale shows 3 kilograms more and it may affect you as much that you are in a bad mood all day and you feel “vanilla”. When it starts to include self-blame for failure, you just want to eat a whole rack of sweets in the pantry and your emergency bucket of ice cream hidden in the freezer.
Keep calm and read on. You will learn that your worries are completely unnecessary, and that weight fluctuations in the range of a few kilograms are completely normal as well as that the number on the scale does not mean anything and that you’re in fact doing much better than you think and you definitely did not fail.
“The average adult can experience fluctuations in body weight of up to 3 kilograms during the day. This is mainly due to body water and the part of the day when they step on the weight,” says Dr. Heinberg of the Cleveland Clinic. 
Is it possible to gain a few kilograms of fat in a day or two?
As soon as the scale hits you with a number three kilograms larger than the one that you saw two days before, you will automatically assure yourself that you have gained fat and the fruit and a piece of chocolate that you had for dinner are to blame.
The fruit and the piece of chocolate are innocent, and the fact that the scale shows 3 kilograms more is not an increase in fat, but something completely different. Just imagine how much food you would have to eat to theoretically manage to gain 3 kilograms of fat. I’ll help you a little with that imagination.
1 kilogram of fat hides approximately 7 700 kcal (32 240 kJ). 
You receive 7 700 kcal, when you manage to eat: 17.7 large McDonalds fries or 60.6 classic “white bread rolls” or almost 6.5 kilograms of cooked rice or drink almost 17 liters of Coca Cola.
In order to theoretically gain 3 kilograms of fat in 2 days, you would have to eat or drink three times as much. And I dare to say that no one sane could do this.
It’s probably clearer why you couldn’t gain three kilograms of fat in those two days, and it’s completely useless to worry about such a presumption. It is even unnecessary to weigh yourself almost every day because body weight fluctuates naturally. Just consider checking your weight once a week, or even two, and monitor other body parameters. But that will be explained later. If you are more interested in fruit and which is best for weight loss, read our article Fruits and weight loss – which fruit has the least calories?
11 most common reasons why scale shows a higher number and fat is not the culprit
“Most of us are not able to eat enough food to gain 4 kilograms of fat in a few days. When you notice such a dramatic increase in the number on the scale, body water is most likely to blame,” Dr. Anita Petruzzeli told Shape magazine. 
Changes in body water can occur for several different reasons. The most common are the effects of nutrition, environment, physical activity, medications and phases of the menstrual cycle in women.
6 nutritional factors influencing weight fluctuations
1. One time you weigh yourself before a meal, the second time after a meal, but don’t forget that each meal also weighs something
When weighing under different circumstances, the result will always be skewed. One of the prerequisites for successful monitoring of body weight development is weighing under the same circumstances each time. In this case, ideally before eating.
Eating food logically causes weight gain due to its weight. Water also occurs naturally in food, which in this form contributes to the “drinking regime”. Energy from food is used to cover the energy needs of the body and in case of excess is stored in the form of glycogen or fat for later use. Waste products of metabolism are eliminated from the body every time you go to the toilet.
If you weighed yourself every hour during the day, you would probably always get a different result.
2. Contents of the intestines
It takes a while for your digestive tract to process the food and completely metabolize it. You can record the highest body weight just before emptying yourselves and the smallest body weight after emptying. Even after emptying, the remnants of yesterday’s lunch are passing through your digestive system. The normal time of digestion is estimated to be between 40-60 hours and the optimal range is 24-48 hours. 
Again, it is necessary to weigh always under the same conditions, ideally on the same day of the week after the use of toilet. You can improve the quality of digestion by focusing on enough fiber in your diet. You should eat about 30 grams of fiber per day. Food rich in fiber and water is “processed and excreted” faster than foods that are generally considered unhealthy. On the contrary, they contain little fiber, but an excess of fat and salt. You can also support the optimal digestive function with soluble fiber in the form of Psyllia. You can read more in the article Psyllium – a fiber beneficial not only for proper digestion.
3. You ate a meal rich in carbohydrates
Due to the possibilities and needs, the body naturally stores carbohydrates in a repository, which is collectively called glycogen. The human body has about 450 grams of glycogen stores, which are used as a source of energy. Trained athletes have a little more glycogen in their muscles. 
How is it possible that beloved pastries, Italian spaghetti or risotto can cause the hand on the scale to go right? The magic is that each gram of glycogen stored binds approximately 3 grams of water. The higher number on the scale is again due to water together with the weight of the food and the filling of the intestines, not fat. 
450 grams of glycogen binds approximately 1,350 g of water. Your weight can thus fluctuate due to the fact that you eat more or less carbohydrates or engage in sports activities that deplete glycogen and water reserves. Everyone who has tried any of the forms of low-carbohydrate diet has experienced this phenomenon and initial weight loss. Unfortunately, their joy is premature, because the first few kilograms lost in a few days are just water and glycogen, not fat.
4. The amount of salt in the diet
More salt in the diet is responsible for more body water retained. Some people are more sensitive to salt intake and may feel bloated. You should take about 5 grams of salt per day, no more. Even if you are not one of those who need to salt every meal, you may have a problem with high salt intake. 
The salt is hidden in various semi-finished products, frozen meals, smoked meals, cheese, pastries, various grilling sauces and fast food dishes. You can easily limit its intake by eating as much fresh and minimally processed food as possible.
5. Irregular drinking regime
When you drink a few more glasses of water than you normally do, it will result in a slight and short-term increase in body weight. It will return to normal as soon as your body copes with it – it will use water where it is needed and excrete the rest.
On the other hand, there is an insufficient drinking regime and the resulting dehydration, which has a negative impact on human health and sports performance. How do you know if you are drinking enough fluids? A simple test of the color of urine, which should be optimally slightly yellow. The darker the yellow color of urine, the greater the level of dehydration. If you are interested in how to take care of your drinking regime, read our article Hydration before, during, after training and how to avoid dehydration.
6. You drank alcohol
You’ve probably noticed that you go for “a number one” more often when you have a beer or a few glasses of wine. This is because alcohol has diuretic effects. However, as soon as you replenish such lost liquids in the form of drinks or food, everything will return to normal. 
But the following scenario is more likely. When consuming alcohol, it almost never stays with one glass. In most people, alcohol stimulates the appetite, especially for salty and fatty foods. Almost no one has a sweet dessert with a beer or wine, but chips, sticks, nachos or various fast food from the restaurant’s menu. This means more energy intake from alcohol and these salty foods. As is well known, salt, on the other hand, retains water and you can observe the weight gain. If you are interested in learning more about the effects of alcohol on weight loss and muscle growth, read our article How does alcohol affect weight loss, muscle regeneration and growth? 
5 lifestyle and training factors affecting weight fluctuations
1. You sweat naturally during sports
We all sweat and not just when doing sports. It is the body’s natural reaction to maintain an optimal internal temperature and prevent overheating. The degree of sweating is individual for each and depends on many external and internal factors. As a result, one person can completely sweat the sportswear, while the other can have only small wet spots in the armpits. 
Logically, after sports you will have less body weight due to fluids sweated out. As soon as you replenish the lost fluids, the weight returns to normal. Sweating more does not mean losing weight. Therefore, it does not make sense to try to intensify sweating during sports activities with several layers of clothing. To learn more about the relationship between sweating, training and weight loss, read our article Sweating and Training – Do We Need to Sweat to Make Exercise Make Sense?
2. You are engaged in intensive sports or strength training
Any form of well-built sports and especially strength training causes muscle damage, which is marked on the muscle cells by the formation of microtrauma. One of the parallel phenomena is local inflammation, when water is retained between and within muscle cells. This mechanism can lead to weight gain.
You can subjectively recognize it on the body as a “muscle soreness”. This delayed onset of muscle soreness, aka DOMS, usually lasts 24-72 hours and is characterized by the fact that you have trouble climbing stairs after leg training or raising your arms after arm training. If you are interested in how to ideally regenerate due to the reduction of “muscle soreness”, read our article Best techniques for regeneration, reduction of muscle soreness and fatigue after training.  
3. Excessive stress
Excessive stress can also cause weight fluctuations of your body. Elevated levels of the stress hormone cortisol are associated with water retention.  
Even long-term caloric deficiency can increase plasma cortisol levels, which may contribute to some extent in body water retention. 
What about that? Try stress-reducing techniques such as yoga, mindfulness or relaxation and wellness treatments such as sauna, winterisation or massages. During weight loss, regularly include a refeed day once every 14 days, when you increase your energy intake by 5-10% above your balanced energy balance.
4. You are a woman and your body weight changes naturally during the menstrual phases
Studies show that body water retention peaks during the first day of menstruation. You can thus observe that your body weight is slightly higher than normal due to the changed hormonal environment. The weight will return to average over the next few days. 
“How substantial this weight fluctuation is is very individual. It usually represents about 1-3.5 kilograms,“ adds nutritionist Amanda Foti. There is no need to panic. The solution can always be to weigh in the same part of the cycle. 
5. You suffer some disease and are taking medication
Fluctuations in body weight can be affected by untreated thyroid disease, diabetes or inflammatory disease of intestinal mucosa. Therefore, it is important to consult your doctor in the event of a sudden and excessive change in your body weight.
There are medications that contribute to greater retention of body water or increased appetite. Such medications include those commonly used in the treatment of diabetes, high blood pressure, mood disorders or migraines. If you are taking such medications and suspect that they affect your weight, consult your doctor.
Are there any other factors that affect the number on the scale?
It may be a little funny, but not every floor is of the same level. If you weigh yourself in several places, you will probably always get a slightly different result.
Even if the batteries in the scale are running low on energy, distorted measurements can occur.
Therefore, always weigh yourself in the same place, under the same conditions and with charged batteries.
How to properly monitor progress and how often to weigh yourself?
The number on the scales does not tell the whole truth, and as you can see, quite often it is very distorted. Therefore, it is necessary to monitor several physical parameters over time and, based on this, get an overall picture of how you are succeeding or not succeeding in meeting your goals.
Weigh yourself once a week, or two, always under the same conditions. Ideally in the morning after the toilet and before breakfast.
Don’t forget to observe body circuits in the same way you weigh yourself – always under the same conditions. Focus on the circumference through the hips, abdomen, waist and possibly other areas that you want to watch.
Watch for changes in clothing. Can you fit in your old jeans even if the weight hasn’t changed? Then you probably lost some fat and gained muscle.
Write down the numbers in a diary or notebook and always write down a note about how you feel in your clothes. Are your pants or t-shirts looser? Great, write it down and brag.
On this “check day” of yours, you can easily take a progress photo of yourself in the mirror. You can look back and see what you have come through.
- If you want or have the opportunity, use devices that measure the composition of the body (muscle mass X body fat) and tell you what specific changes have really taken place.
The number on the scale is growing, but you are slimmer. How is it possible?
This phenomenon has a simple explanation. When the number on the scale does not move or even grows, while you are objectively slimmer and your clothes are looser, you simply gained muscle mass and got rid of a decent amount of body fat.
A kilogram of fat is more voluminous than a kilogram of muscle, although they both weigh the same. It’s a similar situation to imagining a kilogram of feathers vs. kilogram of iron. But this is a matter of weeks and months, not days.
Does weight matter at all?
Body weight is affected by many factors and in itself will never tell the whole truth about the success or failure of weight loss or overall change in body composition. The healthy goal of weight loss is to try to lose weight at a rate of 0.5-1 kilograms per week.
Especially if you are doing strength training, you do not have to observe changes in weight at all. But you will definitely notice smaller body circumferences, better fitting clothes and more visible muscles on your body. Other factors that indicate that you are really doing well include better sleep and skin, a better sex life and more energy during the day. You can easily find yourself feeling healthier and happier. Your own self-esteem should not depend on the number on the scale to which you may be clamping. 
What is the lesson?
A number on the scale may tell you how you’re doing with losing weight or gaining muscle, but it never tells the whole truth. Weight fluctuations in the manner of days are completely natural when you consider food, drinking regime, exercise, hormonal effects and medications used, or current medical condition. Even during the day, body weight can vary by up to 3 kilograms, which is perfectly normal.
Weigh yourself once a week, or even two, under the same conditions each time, and also monitor body circumference values. Together, these values will tell you much more than a single number on the scale.
Don’t spoil the start of a new day by the number on the scale.
Are you worried about weight fluctuations? If you have your own experience and tips on how to look at weight fluctuations and how often you think it is ideal to weigh, do not hesitate to share your observations in the comments. If you liked the article, we’ll be happy if you shared it.
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