In today’s article, we will try to resolve a question “Why do You Lose More WEIGHT Only in the 1st Week of Dieting?“
Many people have to start a diet to lose weight, as they observe that during the first week the weight loss is very significant, but as the weeks go by that weight loss is reduces or even reverses.
One of my readers was told me that “is that the body gets used to the diet and then it is harder to lose weight.” I do not find any basis in that statement, so I will explain, backed by scientific studies, the true reason for that circumstance.
The First Week of Dieting:
If you start a diet with a significant caloric deficit of 1000 kcal per day, it will take about three and a half days to lose approximately 454 grams of body fat. In contrast, the drop in body weight can reach 1.8 kg, largely due to a decrease in body carbohydrates and related to the water reserve.
When we restrict the consumption of food the body will use these reserves, which consist of both fats and especially carbohydrates, stored as liver and muscle glycogen, which can be used for several days when you follow, for example, a low-carbohydrate diet.
As a gram of glycogen is stored with about 3 grams of water, a significant loss of weight occurs. For example, 300 g of glycogen, together with 900 g of water stored with it, would add 1.2 kg of body weight. About 70% of the weight loss in the first days of diet is due to this loss of water. 25% comes from fat reserves and 5% from protein tissue.
If you want to lose as much weight during a period of three days, water restriction is the most effective method, and in fact is the one practiced by many professional bodybuilders before competing and boxers before weighing. But this practice is not recommended for a diet because you would only be lowering the body water level.
In a diet, when you return to the normocaloric level, that is, to maintain the new body weight, there will be a rapid increase of about 1.3 kg. This is due to the recharge of glycogen reserves with the weight of the water that accompanies it.
Also say that the changes in weight that occur in daily body weight, about 1.2 kg, are due to changes in body water that accompany the loss of carbohydrates and proteins, and no changes in lean or fat mass bodily.
And The Next Weeks?
The rapid loss of weight in the first week of the diet is fundamentally due, and as we have explained previously, to the loss of water. As the water does not contain calories, you can lose almost 500 g of weight with a deficit of about 1200 kcal, since 70% of that weight loss is water.
In contrast, the 1200 kcal come mostly from fats and a small part of the proteins. In the second week, however, only 20% of the weight loss will come from the water, so to lose the same amount of weight as in the first week you would need a cost of 2800 kcal.
Already at the end of the third week, water losses are scarce, so to lower those almost 500 g of body weight you would need an energy deficit of about 3500 kcal. Therefore, as you continue the diet, the weight loss requires a higher energy cost because less amount of body water is lost.
The speed of weight loss also decreases over time. The more you lose weight, the less calorie you need to maintain the new body weight. For example, an athlete who weighs 90 kg needs 3400 kcal to maintain his weight. If his weight drops to 82 kg, he would need only 3000 kcal per day.
Suppose that athlete, with 90 kg, wants to have a deficit of 1000 kcal. His diet should be 2400 kcal. But once it falls to 82 kg, to continue with the deficit of 1000 kcal, the diet should be about 2000 kcal. If you do not adjust the caloric deficit to the need that requires your new weight, the deficit would be only 600 kcal, because you would be consuming 2400 kcal needing 3000 to maintain your body weight.
You would continue to lose weight but at a lower rate. Although the speed of weight loss is lower as the diet continues, the weight that is lowered is mainly of body fat, as we have said before as soon as water is lost after the third week of the diet.
Thus, the knowledge of all these data is very important when preparing a diet and understand the development of it. Let us remember by way of summary that in the first weeks the weight loss comes mainly from the reserves of glycogen and water. As you progress in the diet you lose less weight but that loss comes to a greater extent from body fat. If you want to lose the same amount of weight every week it will take us an energy expenditure.
[EXPLAINED] Why do You Lose More WEIGHT Only in the 1st Week of Dieting?
Many people start dieting to lose weight, as they observe that during the first week the weight loss is very significant, but after one or two weeks of Dieting the weight loss is reduced or even reverses. But Why do You Lose More WEIGHT Only in the 1st Week of Dieting? Here is the Explanation.
Hi, This is A. R. Choudhury, a Professional Blogger & part time Freelancer from India. Here at FabHealthFitness, I write about Health, Fitness, Diet, Supplements, Nutrition and more. You can read more about me at About me page.