August 27, 2022

Sugars or carbohydrates are macronutrients (meaning, they are a major source of food) but they are not vital for our existence. Our bodies make enough glucose so we don’t need to take any glucose or other sugars in our foods.

The term carbohydrates means that they are made of carbon atoms and water. There are three general types: monosacharides (glucose, fructose, galactose, xylose); disaccharides (table sugar - sucrose, maltose, lactose, trehalose) and polysaccharides (amylose, cellulose, glycogen) (and some others).

So, if you eat honey and table sugar (which consist of glucose and fructose) as soon as they enter the gut they get absorbed as glucose (which is used by all cells - about 1/3 of the brain and all red blood cells function only on glucose) and fructose which can be metabolised only in liver (hence, non-alcoholic fatty liver disease).

If glucose or sucrose enter our mouths and continue to our guts, our bodies immediately produce insulin (beta-cells of the pancreas). Insulin is an anabolic hormone which means that it is like a prison warden - it has the keys to open “doors” on our cells and push glucose inside. When there is high blood levels of insulin fat can’t be used for energy. Whole metabolism is turned towards “making”, i.e, anabolism. When there is no food body starts to produce glucose and to use its own building blocks (like proteins and, most notably, fats) for energy. This is catabolism! That’s the reason why any diet that insists on five meals a day or similar is not very good. Insulin spikes happen five times a day!!!

Now, let me cite Prof. Dr Robert Lustig. In his famous book, Fat Chance, he says that nature packs its poisons with its antidotes. So, fructose (sugar from fruits) come with lots of fiber. When you bite in a pear or an apple (or some other fruits), you chew it an big chunks of the fruit comes in the stomach and small gut and fructose gets released slowly. That’s the reason it’s much much better to eat whole fruits instead of fruit juices.

We can get fat on any sugars but the impact is much bigger if we eat refined sugars. All breads, potatoes, rice, and similar come under starches which almost immediately turn to glucose. So, it’s just a marginal benefit comparing to honey and table sugar.

A combination of meat, fat, and vegetables for all practical purposes can’t make you fat.

However, combination of fat and carbohydrates is specifically efficient in making people fat.

In biochemistry we used to say: Fats burn on the fire of carbs! (hence, no carbs, no fire, no burning of fats, no fat gain).

Science of carbs metabolism gets further complicated with glycemic index. This is the number describing speed of metabolism of various sugars. Some people can manipulate their diets by introducing and eating comparatively larger amounts of food with low glycemic index.

请大家一起呼吁：祖国文明建设应从央视和国营媒体带头禁刊酒类广告做起。酒，从精神到肉体已经伤害了无数国人！
-《海外南开人网》敬启

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