Pocrescophobia. It's the fear of weight gain, and I see every time I'm around with a health-conscious person at a party or special event. It is enough for them to eat more than they normally could or, worse, eat some foods that are heavy on the carbohydrate and fat side.
It's almost like in this Birdbox movie where you only get a glimpse of one of them The monsters are enough to drive you crazy with fright, but instead of throwing yourself in front of a UPS truck, hurry the Pocrescophobians move to the next mirror, undress and nervously pick up their abs looking for laxity or drowsiness in general  The thing is, eating too much to a meal does not make you fat, even if the "overfeeding" is Caligulian. In fact, it is unlikely that you will receive a single gram of it, and there are some good studies that prove that.
Hansel and Gretel Wont Fatten Up
Scientists fed a cohort of healthy men with a single meal of bread, jam, and fruit juice with a total of 480 grams of carbohydrate (about 1
Most of the carbohydrate was converted to glycogen (346 grams) while the other 133 were burned as fuel. It's true that their bodies converted some of the carbohydrates into fat through a process called De novo Lipogenesis (DNL), but it was barely 2 grams.
During the 10-hour follow-up, however, the subjects burned 17 grams of fat. That's 7 grams more fat than the sum of what's in the meal (8 grams), and the fat they made with DNL (2 grams), so they burned 7 grams of body fat after the meal.
So gross feed resulted in zero net fat loss.
Another study soaked the subjects with carbohydrates for several days. Healthy young adults consumed 150 days of their daily calorie needs for five consecutive days, but the additional 50% of calories came exclusively from carbohydrates (684 grams or 2,736 extra calories per day) (2).
The amount of fat produced (by DNL) was ten times that of a maintenance diet, but it was still only 5 grams per day.
Five days of digging resulted in a gain of only 25 grams of fat or about one-eighth of a pound of fat. That's such a small amount that an anorexic is unlikely even to be blinked.
Why is the fat gain from a big meal so insignificant?
Make no mistake, you gain weight after a piggy meal As highlighted by the researcher Alex Leaf in an article on this topic (3) and mentioned above, it is unlikely that the extra weight is fat or at least one significant amount of fat, especially if the meal or meal rarely or never occurs for a short period (such as a one-week vacation).
Specifically, you could gain a pound of fat if you eat 500 to 1000 calories per day per week, but not if you eat 500 extra or 1000 calories in a single meal. First, there is a limit to how much food your body can turn into fat in one session (via DNL).
This is because different things happen when you eat the equivalent of all foods from column A of a Chinese restaurant menu. Much of it is stored in the liver and muscles as glycogen, and together with every gram of stored carbohydrate, about 3 grams of water accumulates.
The amount of glycogen varies greatly from person to person and can be particularly great in weight lifters. Athletes or muscular people in general, especially if they have been training that day (which causes the glycogen to degrade to some degree).
Then there is the effect that food itself has on the body. Eat a heap of food and your body temperature rises when it's hard to digest (dietary thermogenesis). (Protein is the "most expensive" to metabolize while fat is the cheapest.)
Part of it is also burned by NEAT, or non-use thermogenesis. This is the energy we consume for everything that does not sleep. Eating, dancing or sports – things like walking, typing, gardening and even fidgeting.
The rest of the actual weight gain is greatly influenced by the amount of sodium and water in the meal, both of which have blood volume, and then there is the actual weight of the food that drags through the digestive tract.
However, all of this weight gain is much more transient than adipose tissue (adipose tissue).
Eating crap for 2 weeks does not affect you
Eating clean vs. Orthorexia
- KJ Acheson, et al. Glycogen Synthesis vs. Lipogenesis After a 500 Gram Carbohydrate Meal in Humans, Metabolism, 31.12.12 (12): 1234-40.
- Jim Schwarz et al. "Short-term Changes in Human Carbohydrate Energy Intake Amazing Effects on Liver Glucose Production, De-novo Lipogenesis, Lipolysis, and Whole Body Fuel Selection" J Clin Invest 1995, Dec; 96 (6): 2735-43.
- "?", Examine.
- Alex Leaf and Jose Antonio, "The Effects of Overfeeding on Body Composition: The Role of Macronutrient Composition – A Narrative Overview," Int J Exerc Sci, 2017, 10 (8).