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"Carbohydrates": The Primary Source of Energy and "Insulin": Indispensable for Muscle Growth

"Welcome to the 'Initial Knowledge Acquisition' at GYM CONQUER Blog! Here, we simplify complex topics to spark your curiosity and guide you towards further learning. Approach scientific and medical information with a critical mind—question, understand, and expand your knowledge. Let this be a stepping stone to a richer life."

Many people have a vague idea that carbohydrates are important, often thinking that they should not consume too much because they cause weight gain.

If you're reading this blog, you're likely interested in bodybuilding (including dieting). To enhance growth potential in a short period of time, the "quality," "quantity," and "timing" of your meals become crucial.

By practicing these principles and accumulating personal experience, bulking up (muscle enhancement), dieting, and health improvement can be achieved more easily than you might think.

Let's reacquaint ourselves with the knowledge about carbohydrates!

Here is a 3D wireframe illustration showing the role of carbohydrates as a major energy source and the role of insulin in muscle growth. This image visually represents how different types of carbohydrates—monosaccharides, disaccharides, and polysaccharides—are converted into energy within the human body. It also includes elements symbolizing insulin's role in glucose regulation and its hierarchical function in muscles, liver, and adipose tissue. This design is scientific and educational, emphasizing the biochemical processes involved in the digestion of carbohydrates and the function of insulin, making it suitable for a health and nutrition-focused blog.

Carbohydrates are compounds containing carbon and water, found in staple foods such as rice, bread, buckwheat noodles, and udon. Carbohydrates include both "sugars" and "dietary fibers," with sugars serving as our primary energy source.

Sugars are categorized into three types:


These are the simplest form of sugars, including glucose (dextrose), fructose, galactose, and mannose, which are utilized as energy in our bodies.


These sugars are formed by the bonding of two monosaccharides, with common examples including sucrose (table sugar), lactose (milk sugar), and maltose. Disaccharides are broken down into monosaccharides by digestive enzymes.


These are groups of sugars formed by the bonding of multiple monosaccharides, with starch being a prominent example. Starch, consumed as part of our staple diet, is broken down into dextrins by digestive enzymes and acids, and absorbed in the small intestine for energy use.

The digestion and absorption of carbohydrates occur through a series of processes in the digestive system, starting with breakdown by amylase in saliva within the mouth. This process continues partially in the stomach and completes in the small intestine. The absorbed sugars are processed in the liver, contributing to energy storage and blood sugar regulation.

Now, let’s talk about insulin, a crucial hormone for muscle growth. Insulin's primary role is to lower blood sugar levels. When we eat, blood sugar rises, and insulin is secreted to distribute the glucose to body tissues. Insulin reduces blood sugar by delivering glucose and amino acids to muscles, fat, and the liver, thereby supplying nutrients to cells.

There is an "insulin hierarchy" in how it functions:

  1. Muscles

  2. Liver

  3. Fat

This hierarchy suggests that the more muscle mass one has, the less insulin acts on body fat. Having more muscle makes it harder to gain weight, not only because of a higher basal metabolic rate but also due to insulin's role.

For those with less muscle mass, a greater proportion of insulin acts on body fat, leading to easier fat gain.

To enhance insulin's function, there are several methods. For instance, the intake of amino acids like arginine, citrulline, and ornithine can increase insulin secretion and sensitivity. EPA (eicosapentaenoic acid) and alpha-lipoic acid also enhance insulin sensitivity. Cinnamon has been reported to improve blood sugar levels, aiding in diabetes management. Additionally, using the glycemic index (GI) to control blood sugar spikes is crucial. Consuming low-GI carbohydrates helps avoid rapid increases in blood sugar, which can lead to sharp decreases from insulin, causing blood sugar volatility and potential vascular damage.

Returning to sugars, let’s talk about fructose. While fruits are generally considered healthy, recent studies have indicated that due to its unique properties and metabolic pathways, fructose might pose several health risks.

Triglycerides / Fatty Liver

Fructose is processed through a different metabolic pathway than other sugars (like glucose), being taken directly into the liver. Unlike glucose, fructose does not require enzyme regulation before entering glycolysis, leading to potential increases in triglyceride accumulation. This characteristic can heighten the risks of elevated triglycerides and fatty liver due to excessive fructose intake.


Fructose is involved in glycation, a process where sugar reacts with proteins to form AGEs (Advanced Glycation End products), which accumulate and impair tissue and vascular proteins. For example, abnormal collagen binding caused by AGEs can reduce tissue elasticity, leading to arteriosclerosis and skin aging. AGEs also induce oxidative stress and promote inflammatory responses.

Given these issues, it’s worth reconsidering fructose intake, especially from high-fructose corn syrup and processed foods. Alternatives like stevia, erythritol, and xylitol—low-calorie natural sweeteners—have a lesser impact on blood sugar, aiding in the management of diabetes and obesity.


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