Weight loss: why you don’t just lose fat when you’re on a diet

If you go on a weight-reduction plan, you don’t simply lose fats – you lose muscle too. This will have many repercussions – not solely in your health and energy, however in your metabolism.

To shed pounds (physique fats), you’ll want to be in a calorie deficit. This implies
consuming fewer energy than your physique makes use of, or exercising to burn extra energy than you eat.

Through the first few days in a calorie deficit, the physique makes use of up its small reservoir of glycogen shops for vitality. Glycogen is a string of glucose (sugar) that comes from the carbohydrates you eat. Since carbs are the physique’s fundamental vitality supply, that is why any glucose the physique doesn’t instantly use is saved to make use of for vitality later.

However as carbohydrate molecules bind with water, which means when the physique shops glycogen, it additionally shops water within the muscular tissues. As these glycogen shops are used up, the physique additionally releases a big quantity of water. That is typically known as “water weight”, and explains why some could really feel they lose appreciable weight early of their weight-reduction plan.

Given you solely have days’ value of glycogen shops, that is why the physique makes use of fats to retailer further energy for if you want it. As soon as the glycogen shops are used up, the physique shifts to metabolising fats to get the vitality it must perform.

However not all tissues can use fats for vitality – such because the mind. For this reason the physique must metabolise your muscular tissues if you’re in a calorie deficit.

Protein (from the meals you eat) is saved in your muscular tissues. The physique can convert this saved protein into glucose for vitality. However this implies you subsequently lose the muscle tissue itself when that occurs. This has important penalties – together with slowing the metabolism, which can in the end drive weight regain after dropping pounds.

Muscle loss

Many components can have an effect on how a lot muscle you lose whereas in a calorie deficit.

Whereas it was as soon as thought that the extra fats you had, the much less muscle you misplaced in a calorie deficit, this has since been disproved – with each lean and overweight folks dropping important charges of muscle when weight-reduction plan.

Ethnicity and genetics could, nevertheless, play a job – with research displaying black folks are likely to lose extra muscle mass in a calorie deficit than white folks do. Some analysis additionally means that genetic variants could make some folks extra prone to sure dietary modifications, which can decide how a lot muscle mass they find yourself dropping.

Muscle loss may even occur no matter whether or not you shed pounds steadily or shortly. A greater determinant of how a lot muscle you’ll lose depends upon how a lot weight you find yourself dropping. If an individual loses 10% of their physique weight, usually round 20% of that is fat-free mass (the proportion of physique mass that isn’t fats – akin to muscle). This will equate to a number of kilograms of muscle.

Many individuals additionally assume that what you eat whereas dropping pounds could decide how a lot muscle you lose, with it generally believed that in case you eat loads of protein you’re much less prone to lose muscle mass. That is debatable, with analysis displaying folks lose as a lot muscle on high-protein weight reduction diets as individuals who adopted different varieties of diets.

Low-carb diets have additionally been claimed to advertise extra fats loss. However research evaluating several types of diets have discovered that low-fat high-carb diets appear to supply the identical, if not higher, fats loss than low-carb, high-fat diets – with no variations in muscle loss.

Protein and train

Given all that has been mentioned, the one solution to stop muscle loss considerably whereas dropping pounds is to mix train (significantly resistance train and endurance train) with a weight-reduction plan increased in protein. It is because train stimulates muscle development – however this course of can solely occur when you have an satisfactory provide of protein.

It’s advised adults usually goal to eat 0.8g of protein per kilogram of physique weight per day to take care of muscle mass. However given the additional demand train locations on the muscular tissues, an individual will most likely must eat 1.2-1.5g of protein per kilogram of physique weight to protect muscle throughout weight reduction. Individuals who train lots may have to extend that to greater than 2g per kilogram of physique weight when dropping pounds. Older folks can also must eat extra protein than common.

Simply be cautious of consuming an excessive amount of protein (greater than 2.5g per kilogram of physique weight) as consuming greater than your physique makes use of may have an antagonistic impact in your metabolism by doubtlessly making the physique much less in a position to attract upon glucose for vitality. It could additionally put better stress on the kidneys and liver – which may result in critical well being points, akin to liver and kidney injury.

Even in case you stop muscle loss when dropping pounds, different metabolic modifications nonetheless occur that promote weight regain – akin to modifications in your metabolic charge (the minimal quantity of energy your physique must survive) and will increase in urge for food and starvation. For this reason, when attempting to shed pounds, a very powerful factor to contemplate is how sustainable your weight-reduction plan and way of life modifications are. The better these are to take care of, the higher possibilities you may have of retaining the load off.