The relationship between obesity and blood sugar and the value of a low-glycemic diet

5.4.4 The Relationship Between Obesity and Blood Sugar

The sugar in blood serum is called blood glucose, which is mostly glucose and comes from carbohydrate foods we eat, such as fruits, staple foods, and sugars.

Under normal circumstances, the human body's blood sugar can be maintained in a certain balance: eating → blood sugar rises → the body secretes more insulin → promotes the conversion of blood sugar into fat and glycogen → blood sugar drops → insulin decreases.

If you unfortunately belong to the group with poor glucose tolerance (making up about 1/4 of the population), and you don't pay attention to your diet, your blood sugar level may suddenly spike in a short period of time and be difficult to lower with the help of insulin, potentially leading to insulin resistance. Blood sugar becomes less sensitive to insulin stimulation, resulting in persistently high blood sugar and increased insulin secretion. Insulin promotes fat synthesis and inhibits fat breakdown. Therefore, you will gradually gain weight.

The World Health Organization states in its diagnostic criteria for diabetes that: normal fasting blood glucose in the morning is 3.9–6.1 mmol/L; diabetes can be diagnosed when fasting blood glucose in the morning is ≥7.0 mmol/L or random blood glucose is ≥11.1 mmol/L; while fasting blood glucose of 6.1–6.9 mmol/L and postprandial blood glucose of 7.8–11.1 mmol/L are prediabetes (impaired fasting glucose or impaired glucose tolerance).

It's worth noting that routine annual physical exams typically only check fasting blood glucose. In fact, many people with normal fasting blood glucose levels may have high postprandial blood glucose. High postprandial blood glucose needs to be monitored and controlled.

The more stable an individual's blood sugar levels, the more stable their weight will be. However, if you frequently overeat or skip meals, your blood sugar levels will fluctuate wildly, making you more prone to weight gain. Furthermore, consistently high blood sugar levels can lead to increased visceral fat and a larger waistline.

The root cause of stress-related obesity is also related to blood sugar: many people feel that the busier they are, the fatter they get, because stress increases hormones, which leads to a rise in blood sugar levels.

Blood sugar inevitably affects weight. Eating raises blood sugar levels, which can eventually lead to obesity. Therefore, if you want to lose weight, you need to regulate your body's blood sugar levels.

5.4.5 The value and significance of low glycemic index diets for diabetic patients

The glycemic index (GI) refers to how much a carbohydrate in food raises blood sugar levels. A higher GI means a greater spike in blood sugar. Consuming a high-GI diet regularly or over a long period increases the risk of diabetes and its complications. Years of research have identified an effective non-pharmacological treatment for diabetes called a low-GI diet. This method was initially developed for treating diabetes. Later studies found that choosing low-GI foods instead of traditional high-GI foods has significant clinical benefits for diabetic patients. A GI below 55 is considered low-GI.

When insulin is used to treat diabetes, patients typically start with 15 units, gradually increasing to 20 units, then 30 units, and if control is not achieved, 50 units, and eventually 80 units. Patients injecting more than 30 units often have essentially necrotic pancreas, and such patients can never replace insulin with dietary therapy. The amount of insulin injected depends on the amount of sugar consumed. If a low-glycemic index diet is started, the need for insulin decreases, so although insulin injections are still being administered, the dosage can be significantly reduced.

For example, if a patient injects 50 units of insulin, they may not experience any problems for the first few days. However, on the third day, they may start experiencing dizziness, headaches, or even various symptoms of hypoglycemia, indicating that their blood sugar has decreased. But it's important to prevent the blood sugar from dropping to a hypoglycemic level. Therefore, the insulin dosage is reduced to 40 units, and the patient's reaction is monitored for several days after the injection. If hypoglycemia symptoms reappear a few days after the insulin injection, the dosage can be further reduced to 20 units.

What is the significance of lowering insulin levels? Any substance, if used continuously, will inevitably lead to adaptation and tolerance. Once tolerance to insulin is established, it means you are forced to watch your blood sugar remain high, your blood vessels become damaged and narrowed, and in severe cases, lower limb necrosis, blindness, and even myocardial infarction may occur. The higher the insulin dosage, the stronger the patient's tolerance becomes.

Insulin is a hormone that can stimulate the growth of cancer cells. Therefore, reducing insulin dosage can lower the risk of cancer. The significance lies not in stopping the medication, but in reducing the dosage. For those taking less than 30 units or taking it orally, can they eventually stop taking the medication? British research shows that choosing to eat specific low-glycemic index foods instead of traditional high-glycemic index foods for 92 days, followed by stopping medication, can maintain this effect for 5 years. After 5 years, approximately one month of medication is needed, and then it can maintain the effect for another 5 years.

Should diabetics use insulin or eat low-glycemic foods? Of course, to control weight, your diet also needs to meet the standards of a negative energy balance and nutrient enrichment. Weight control is crucial for diabetes management.