Actually, this is not entirely true. This paradigm is outdated and not supported by the science and research. In Gary Taubes book, “Why we get fat and what to do about it”, he goes over the evidence of why this “calories in verses calories out” paradigm is false.
Body fat is regulated like all other tissue in our body: hormones. Many hormones affect fat deposition and fat release. Hydrocortisone, Estrogen, Testosterone, Glucagon-like Peptide, Thyroid hormone, and some others. And the most potent of all these hormones affecting fat and glucose metabolism is insulin. Insulin trumps other hormones. If insulin levels are high: 1) The body’s cells will primarily burn carbohydrates instead of fats, 2) Glucose will get stored in liver as Glycogen, 3) Excess glucose will get converted into free fatty acids in the liver, 4) Adipose tissue will store fat and not release it. This science is not controversial and we’ve known this for over a half century.
Most of our body’s cells can use either carbohydrates or fat to make ATP. only our neurons and a few specialized cells need carbs. Our liver can only store a rather small amount of Glycogen. Our body can store a lot of fat, even in people are are not overweight. Also, fat is basically twice as energy dense as carbs. It is apparent that our bodies are suppose to use fat as primary energy source.
In essence, if we lower our insulin levels, the body will do several things: 1) Fat will be free to come out of adipose tisue, 2) Our body’s cells will begin to burn fatty acids to make ATP instead of only carbohydrates.
Ideally we are suppose to eat a low glycemic index meal which invokes a moderate insulin response. Our adipose tissue slightly fattens for a few hours after a meal and our body goes into carbohydrate-burning mode for a few hours. Then as insulin levels fall, the reverse happens and our adipose releases fat. Adipose is suppose to be a temporary storage buffer which provides energy for the several hours inbetween meals after our food has been digested. Ideally, we are suppose to be in “carbohydrate burning and fat storage mode” for only a short portion of the day and in “fat burning, fat-release” mode for most of the day.
To get back to point of the original post: Berries have a lower glycemic index than most fruits. Adding berries to Huel is probably a good idea if someone is trying to lose body fat.