[Kim Jaeho's Life Story]<276> Complications Far More Frightening Than Diabetes

Published 03 Apr.2026 12:00(KST)

According to the 2024 National Health and Nutrition Examination Survey, the prevalence of diabetes was 13.3% for men and 7.8% for women. According to the Health Insurance Review and Assessment Service, the number of people receiving medical treatment for diabetes increased by 18.9% over four years, from 3.33 million in 2020 to 3.96 million in 2024. These statistics, along with the fact that many people around us struggle with diabetes, show that diabetes is close to us and not just someone else's problem.

Diabetes refers to a state in which blood glucose, or blood sugar, remains consistently high. The name comes from the fact that glucose, which cannot be reabsorbed by the kidneys, is excreted in the urine. If high blood sugar continues in diabetes, what problems might it cause for us?

The cells in our body survive by taking in glucose from the blood and using oxygen to convert it into energy. Therefore, if blood sugar drops too low, the cells starve. Hypoglycemic shock, which diabetes patients experience when their blood sugar is too low, results in cold sweats, tremors, dizziness, and decreased consciousness, and these symptoms can become severe and life-threatening if prolonged.

While hypoglycemic shock due to low blood sugar is dangerous, why is having too much blood sugar also problematic? When blood sugar is too high, substances like fat accumulate on the walls of blood vessels, forming clots (thrombi). These clots can block blood vessels, causing them to narrow and impeding proper blood flow, which leads to atherosclerosis.

When high blood sugar from diabetes persists for a long time and atherosclerosis worsens, the supply of nutrients and oxygen to the blood vessels decreases, leading to vascular damage. Consequently, the nerves that receive nutrients and oxygen from these blood vessels are also damaged. Depending on the location of the damaged blood vessels and nerves, various complications can occur. These diabetic complications can severely reduce quality of life and, if severe, may become life-threatening.

Today, diabetes ranks 6th to 7th among causes of death in Korea. In 2024, 11,064 people died from diabetes, accounting for 3.1% of all deaths. Among those who die from diabetic complications, a particularly high number die from cardiovascular disease. The risk of death from cardiovascular disease is said to be 2 to 3 times higher for men and 3 to 5 times higher for women with diabetes compared to those without diabetes.

Recently, research has drawn attention showing that cancer-related mortality is higher among patients with type 2 diabetes than in the general population. According to a study by a British diabetes research institute published in the January 2023 issue of the international journal 'Diabetologia,' overall cancer mortality among type 2 diabetes patients was 18% higher than that of the general population. Specifically, mortality from colorectal, pancreatic, and liver cancer was 2.4 times, 2.12 times, and 2.13 times higher, respectively.

Let’s take a closer look at the complications of diabetes. In most developed countries, the most common complications of diabetes are cardiovascular disease, retinopathy, kidney disease, and peripheral vascular disease, and Korea is no different.

First, coronary artery disease, which occurs when the coronary arteries supplying nutrients and oxygen to the heart are damaged and blocked, can lead to heart attacks. This is one of the most common complications in diabetes patients and a leading cause of death. The risk of cardiovascular disease increases even further if a diabetes patient also has risk factors such as high blood pressure, hyperlipidemia, smoking, obesity, or lack of exercise.

Second, retinopathy, which results from damage to the blood vessels in the retina at the back of the eye, is another major complication of diabetes. Diabetic retinopathy is the leading cause of vision loss, and diabetes also increases the risk of glaucoma and cataracts. Complications of diabetes can severely reduce quality of life, and not infrequently result in death.

Third, diabetic kidney disease is also a very common complication of diabetes. The kidneys contain millions of glomeruli that filter waste from the blood. When many small blood vessels in the glomeruli are damaged and the kidneys can no longer function properly, it leads to renal failure. In this case, the patient may require dialysis or even a kidney transplant to filter waste products.

Fourth, peripheral vascular disease, which often appears in the toes or feet, is another common complication. If blood flow to the legs and feet is insufficient due to vascular damage, ulcers and infections heal poorly, nerves may be damaged causing tingling and pain, and sensation in the feet may be lost. If a large area of tissue becomes infected and dies, amputation of a toe, foot, or part of the leg may be necessary.

In addition, stroke, caused by damage to blood vessels in the brain that become blocked or burst, is also a common complication. High blood sugar from diabetes provides an environment conducive to the growth of bacteria and fungi, and the body's ability to heal itself is diminished. As a result, a person may experience various infections, including bacterial and fungal infections of the bladder, kidneys, vagina, gums, feet, and skin. People with diabetes are also more likely to have hearing loss, and they are at higher risk for dental caries, gingivitis, periodontitis, and tooth loss.

For those unfamiliar with diabetes, hearing about its complications might be surprising—diabetes is indeed a frightening disease. As described above, complications from prolonged diabetes can severely reduce quality of life and often lead to death, making it very important to properly manage diabetes and prevent its complications.

To prevent diabetic complications, it is necessary to address the causes of diabetes and either prevent the disease or cure it once it has developed. Modern medicine recognizes that both genetic and environmental factors play important roles in diabetes, but the exact causes of diabetes are not yet clearly understood. As a result, unfortunately, efforts are focused mainly on alleviating the symptoms of diabetes.

Diabetes primarily presents in two forms: type 1 and type 2. In type 1 diabetes, little or no insulin hormone required for blood sugar regulation is produced. In contrast, in type 2 diabetes, insulin is usually secreted normally and signals are sent to cell receptors, but the cells do not open their doors to take in glucose because of insulin resistance. Type 2 diabetes accounts for 90 to 95% of all diabetes cases.

Various medications are used to treat type 2 diabetes, including drugs that improve insulin resistance, stimulate insulin secretion, increase insulin secretion while suppressing glucagon secretion, and inhibit glucose reabsorption in the kidneys. However, these drugs do not address the fundamental issue of insulin resistance, so the goal is only to alleviate symptoms, and the side effects of the medications can be bothersome for patients.

So, what are good ways to prevent diabetic complications? To do this, it's necessary to look more closely at the causes of diabetes.

The cells in our body operate continuously 24 hours a day, so a steady supply of blood glucose is essential for survival. The amount of blood sugar rises sharply when food is digested and glucose is absorbed, then drops rapidly after absorption ends, creating a severe imbalance between blood sugar supply and demand. Our bodies solve this imbalance by appropriately using two hormones, insulin and glucagon.

After eating, when food is digested and glucose is absorbed, blood sugar levels rise rapidly. Beta cells in the pancreas then increase secretion of insulin. The increased insulin stimulates insulin receptors on cells, promoting the use of blood sugar, and also signals the liver to convert some glucose into glycogen, lowering blood sugar to an appropriate level.

After digestion ends and the amount of absorbed glucose decreases so that blood sugar supply falls below usage, blood sugar drops below the appropriate level. At this point, glucagon secreted from the alpha cells in the pancreas signals the liver to convert stored glycogen back into glucose, raising blood sugar to an appropriate level.

Our bodies are equipped with a perfect system to keep blood sugar within an appropriate range. If we maintain this marvelous system well, blood sugar will not stray outside the normal range and there will be no problems. However, when unhealthy lifestyle habits are repeated, this system fails to function normally, leading to issues with blood sugar regulation.

When we develop diabetes, we should not simply assume that taking medication is enough. Our bodies have a system encoded in our genes that regulates blood sugar within the appropriate range inside cells—this is the omnipotent intelligence, the "best physician prepared within my body." We need to note that the cause of diabetes is that this system is not functioning properly.

If this valuable system fails to function due to unhealthy lifestyle habits and you develop diabetes, you should remember that creating a good environment for the "best physician within your body" to work energetically can help restore the system to normal. You should correct your unhealthy lifestyle habits; living this way is what is called "Newstart" (see Part 6 of Life Story).

The first of the eight elements of Newstart is eating a variety of fruits, vegetables, and grains—whole, plant-based foods—without being selective about specific items, and avoiding excessive intake of sugar, processed or refined carbohydrates, saturated and trans fats, salt, and alcohol, which can cause many problems. It is also important to practice the other Newstart elements: exercise, water, sunlight, moderation, air, rest, trust, and love.