Why does eating sugar cause weight gain?

Generally, the reasons why consuming sugar can lead to weight gain include high caloric intake and energy surplus, blood glucose fluctuations and insulin resistance, hyperinsulinemia, metabolic syndrome, and type 2 diabetes. Details are as follows:

1. High Caloric Intake and Energy Surplus: Sugar is a high-calorie food. When excessive sugar is consumed, if the energy it provides is not promptly burned off, it gets converted into fat and stored in the body, leading to weight gain. Sugar intake should be controlled, consumption of high-sugar foods reduced, and intake of low-calorie, high-fiber foods such as vegetables, fruits, and whole grains increased.

2. Blood Glucose Fluctuations and Insulin Resistance: Consuming large amounts of sugar causes rapid increases in blood glucose levels, followed by sharp declines. These fluctuations stimulate insulin secretion, promoting glucose absorption and conversion into fat. Long-term excessive sugar intake may reduce insulin sensitivity, worsening fat accumulation. Dietary structure should be improved, sugar intake reduced, and intake of dietary fiber and protein increased.

3. Hyperinsulinemia: Long-term excessive sugar intake leads to over-secretion of insulin, causing insulin levels in the blood to exceed the normal range. High insulin levels prompt the liver to absorb and store excessive glucose, converting it into fat and resulting in weight gain. Medications such as Metformin Hydrochloride Sustained-Release Tablets, Pioglitazone Hydrochloride Tablets, and Rosiglitazone Maleate Tablets may be used under a doctor's guidance to lower blood glucose levels.

4. Metabolic Syndrome: Metabolic syndrome is a disorder characterized by metabolic abnormalities such as obesity, hypertension, and hyperglycemia. Long-term excessive sugar intake is a key factor contributing to metabolic syndrome. Excessive sugar intake leads to energy surplus, causing obesity, which in turn increases the risk of hypertension, hyperglycemia, and hyperlipidemia. Antihypertensive, hypoglycemic, and lipid-lowering treatments such as Valsartan Tablets, Glimepiride Tablets, and Atorvastatin Calcium Tablets may be used as directed by a physician.

5. Type 2 Diabetes: Long-term excessive sugar intake may lead to insufficient insulin secretion or insulin resistance, eventually triggering type 2 diabetes. Excessive sugar intake causes persistent elevation of blood glucose levels, damaging pancreatic β-cells and reducing their ability to secrete insulin, often accompanied by symptoms such as frequent urination and increased appetite. Treatments such as Insulin Glargine Injection, Insulin Aspart Injection, and Insulin Degludec Injection may be administered under medical guidance to lower blood glucose levels.

To maintain a healthy weight and prevent related diseases, it is recommended to control sugar intake, improve dietary structure, increase physical activity, and undergo regular health check-ups.