In this blog post, we’ll take a scientific look at the actual role and mechanism of enzymes—which are gaining attention as health supplements—as well as the myths and truths surrounding enzyme supplements.
“Are enzymes really that good?” This is a common advertising slogan we often see in newspaper articles or online media. It lures consumers by raising expectations that simply taking enzymes will strengthen the digestive system and completely heal any ailments. Most people purchase and consume dietary supplements, such as enzyme products, to improve their health. Enzymes are advertised as if they were a panacea, with claims that they are effective for relieving fatigue, losing weight, and even preventing aging. While this may seem like an easy solution for consumers seeking to alleviate their health anxieties, in reality, there is often insufficient scientific evidence to support these claims. Of course, some digestive enzymes can help support digestion in specific situations, but generally speaking, simply taking enzymes does not lead to a dramatic improvement in overall bodily function. Enzymes are mostly composed of proteins, and to function properly in the body, they must act at specific sites according to intricate biochemical mechanisms. However, the general public, who often lack access to this specialized scientific knowledge, frequently pay high prices for enzyme-based foods—believed to be beneficial for health—without much skepticism. This is also a problem stemming from the asymmetry of health information in modern society, as consumers are easily influenced by exaggerated advertising or inaccurate information. Therefore, this article aims to provide an easy-to-understand explanation of the functions, mechanisms of action, and various types of enzymes.
As mentioned earlier, enzymes are mostly composed of proteins. Enzymes are spherical proteins made up of numerous amino acid residues, and they must form a specific three-dimensional structure to function properly. Humans exhibit various biological characteristics based on the DNA information stored in 23 pairs of chromosomes. Similarly, enzymes are formed when amino acids are linked together like a chain and then complexly folded and twisted to form a unique structure, thereby becoming active. For example, just as a person’s physical appearance is influenced by genes inherited from their parents, the digestive enzyme pepsin is able to break down proteins in the stomach by forming a specific amino acid sequence and structure through the process of protein synthesis within cells. The structure and function of these enzymes are extremely important because, beyond being mere proteins, they play an essential catalytic role in the complex metabolic processes of living organisms.
Enzymes bind to substrates—that is, reactants—to form an enzyme-substrate complex, thereby lowering the activation energy of a chemical reaction and facilitating the reaction. Activation energy is the minimum amount of energy required for a chemical reaction to occur; when an enzyme lowers this barrier, the reactants can more easily transform into other substances. Pepsin, mentioned earlier as an example, binds to proteins and breaks them down into smaller units called polypeptides. This is similar to an enzyme creating a gentle detour instead of a path that requires crossing a high mountain. As a result, chemical reactions proceed more efficiently. However, in addition to pepsin, the human body contains a wide variety of enzymes. An internationally standardized system has been established to classify enzymes, which are divided into several categories based on the types of reactions they catalyze. Currently, the international enzyme classification system is broadly divided into oxidoreductases (EC 1), transferases (EC 2), hydrolases (EC 3), lyases (EC 4), isomerases (EC 5), ligases (EC 6), and transporters (EC 7). Each enzyme plays a crucial role in digestion and metabolism, and some are also involved in detoxification and immune-related reactions. Furthermore, enzymes are produced and act at specific sites, and an excess or deficiency of a particular enzyme can lead to various diseases and functional abnormalities. This is also why simply consuming enzymes does not necessarily yield the expected results. For example, even if you consume an enzyme that is supposed to act in tissues outside the digestive tract, it is not easy for that enzyme to be absorbed directly into the bloodstream and transported to the necessary site. This is because most enzymes are proteins and are broken down into amino acids or small peptides during digestion before being absorbed.
Enzymes have different structures depending on their type and selectively catalyze only one specific reaction or very similar reactions within the body. This phenomenon is called enzyme-substrate specificity. Enzymes possess specific active sites determined by their structure, and a reaction occurs only when a substrate that fits that shape binds to the site. In the past, this property was explained using the lock-and-key model. Just as the old saying goes, “Everything has a match,” it was thought that for each of the countless substrates—the “locks”—there existed a corresponding enzyme—“key.” However, this theory alone could not fully explain how enzymes lower the activation energy to catalyze reactions. This led to the emergence of the induced-fit theory. According to the induced-fit theory, the substrate does not fit perfectly into the enzyme’s active site from the start; rather, as the substrate binds, the enzyme’s structure undergoes slight changes, forming a more stable complex. This process is similar to fitting together the pieces of a puzzle. Although they may not seem to fit perfectly at first, their shapes harmonize to form an optimal state. Thanks to this structural change, the chemical reaction can proceed more efficiently. Thus, the interaction between enzymes and substrates can be considered the core principle behind the countless metabolic processes that occur within living organisms.
However, there are factors that interfere with the reaction between enzymes and substrates: enzyme inhibitors. Enzyme inhibitors are broadly classified into competitive and non-competitive inhibitors. Competitive inhibitors compete with the substrate to occupy the same active site. In contrast, non-competitive inhibitors bind to other sites on the enzyme, altering its structure and, as a result, preventing the substrate from binding to the active site. To put it simply, this is similar to a situation where multiple cars are competing for a single parking space. Competitive inhibitors are like cars trying to claim a parking space before the substrate does. Non-competitive inhibitors, on the other hand, are more like a situation where the structure of the parking lot itself is altered, preventing cars from parking normally. In this way, enzyme inhibitors play a crucial role in regulating the rates of various reactions within the body by modulating or inhibiting enzyme activity.
Enzymes are essential substances for maintaining homeostasis and ensuring the body functions normally. As explained earlier, enzymes act at specific sites and react with suitable substrates through various regulatory processes. When people consume digestive enzymes in the form of functional foods or medications to aid digestion, they may experience some benefit. However, there is insufficient scientific evidence to support the belief that specific enzyme-containing foods can cure all diseases in the body or dramatically improve health. To maintain a healthy life, it is more important to follow a balanced diet, engage in regular exercise, get sufficient sleep, and maintain healthy lifestyle habits rather than relying excessively on specific enzyme supplements. Furthermore, rather than relying solely on external sources of enzymes, it is important to learn and practice ways to maintain a healthy physical condition so that our bodies can properly produce and utilize the enzymes they need.
