What are the causes of high blood sugar?
Jun 18, 2025
Source: Cainiu Health
Dr. Liu Feng
Introduction
High blood sugar is generally caused by excessive intake of high-sugar foods, lack of physical activity, type 2 diabetes, chronic pancreatitis, Cushing's syndrome, and other conditions. It can usually be managed through dietary adjustments, exercise intervention, medication, surgical treatment, and other methods, depending on the specific cause. In daily life, it is important to maintain a low-sugar, low-fat diet, avoid overeating, engage in regular physical activity, and monitor blood glucose levels regularly.
High blood sugar is generally caused by excessive intake of high-sugar foods, lack of physical activity, type 2 diabetes, chronic pancreatitis, Cushing's syndrome, and other conditions. It can usually be managed through dietary adjustments, exercise intervention, medication, or surgical treatment, depending on the specific cause. If abnormalities occur, timely medical consultation is recommended. Detailed explanations are as follows:
1. Excessive intake of high-sugar foods
Consuming large amounts of sugary foods in a short period overwhelms the body's ability to metabolize glucose, causing a rapid rise in blood sugar levels. Adjusting the diet by reducing high-sugar food intake and increasing dietary fiber can promote glucose metabolism. Usually, no medication is needed, and blood sugar levels can gradually return to normal.
2. Lack of physical activity
Long-term physical inactivity reduces the body's efficiency in utilizing glucose, leaving excess glucose unutilized by tissues such as muscles, leading to elevated blood sugar levels. Increasing daily physical activity—such as walking, jogging, or swimming—can enhance insulin sensitivity and help lower blood sugar. Consistent, regular exercise can gradually improve blood sugar levels.
3. Type 2 diabetes
Due to insufficient insulin secretion or impaired insulin function, glucose cannot effectively enter cells for utilization, accumulating in the bloodstream and causing elevated blood sugar levels. Common accompanying symptoms include increased thirst, frequent urination, increased appetite, and weight loss. Treatment should follow medical advice and may include hypoglycemic medications such as metformin hydrochloride tablets, gliclazide modified-release tablets, or repaglinide tablets.
4. Chronic pancreatitis
Chronic inflammation of the pancreatic tissue damages pancreatic beta cells, reducing insulin secretion and consequently causing elevated blood sugar levels. Accompanying symptoms include recurrent abdominal pain, diarrhea, fatty stools, and weight loss. Treatment involves controlling pancreatic inflammation, and pancreatic enzyme enteric-coated capsules may be taken under medical guidance to improve digestion. Additionally, hypoglycemic agents such as insulin injections or glimepiride tablets may be used depending on blood sugar levels.
5. Cushing's syndrome
Excessive secretion of glucocorticoids by the adrenal cortex inhibits insulin action and promotes glycogen breakdown in the liver, leading to elevated blood sugar levels. Accompanying symptoms include central obesity, hypertension, purple striae, and fatigue. If caused by an adrenal tumor, surgical removal of the tumor is required, and blood sugar and hormone levels should be closely monitored.
In daily life, maintaining a low-sugar, low-fat diet, avoiding overeating, engaging in regular physical activity, and monitoring blood sugar levels regularly are recommended. If symptoms such as increased thirst and urination, sudden weight loss, or unexplained obesity occur, prompt medical consultation is necessary to identify the underlying cause, receive standardized treatment, and prevent complications caused by prolonged high blood sugar or disease progression.
