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November 13, 2025
Marianne Waldenfels
Type 2 diabetes can result from poor diet and lack of exercise. An expert explains how you can avoid the disease through simple, effective changes in everyday life.

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With
Dr. med. Alexandra Schoeneich
Diabetes mellitus has long since become a widespread disease. In Germany alone, over eight million people are living with the diagnosis – and the trend is rising. “Our unhealthy Western lifestyle, characterized by too little exercise and the consumption of processed, high-calorie foods and sugary drinks, leads to weight gain, insulin resistance, and type 2 diabetes,” explains Dr. Alexandra Schoeneich, partner at the Diabetes, Hormone, and Metabolism Center at Isarklinikum Munich. The good news: Type 2 diabetes can often be prevented or at least significantly delayed with a healthy lifestyle.
In diabetes, the blood sugar level is permanently elevated. While type 1 diabetes is usually genetic and occurs in childhood or adolescence, type 2 diabetes develops gradually – often over years. Overweight, lack of exercise, and an unfavorable diet are the main risk factors.
The body's cells become increasingly insensitive to the hormone insulin, which is supposed to transport sugar from the blood into the cells. How much does sugar consumption affect the diabetes risk? Dr. Schoeneich: “It always depends on the amount of sugar and how the sugar is consumed - alone or accompanied by fat or protein. That is better, for example within a meal.
Isolated sugars cause blood sugar levels to rise faster than sugars that come accompanied, like a piece of plum cake with cream. Daily and frequent consumption of sugar, whether isolated or accompanied, can, besides overweight, promote insulin resistance and thus increase the risk for type 2 diabetes."
Regular physical activity improves the insulin sensitivity of the cells and lowers the blood sugar level. It doesn’t have to be high-performance sports: brisk walking, cycling, swimming, or dancing are ideal. Regularity is important – integrate exercise into your daily life, take the stairs instead of the elevator, and walk more often. “150 minutes of moderate exercise and at least two moderate strength sessions per week can reduce the risk of type 2 diabetes,” says Dr. Alexandra Schoeneich.
Excess weight, especially belly fat, significantly increases the risk of diabetes. Even a moderate weight loss of five to ten percent can significantly improve insulin sensitivity. Set realistic goals and avoid crash diets—a slow, sustainable weight loss is more promising.
A balanced diet is key to prevention. Focus on whole foods: whole grains instead of white flour, plenty of vegetables and fruits, healthy fats from nuts, olive oil, and fatty fish. Reduce sugary drinks and processed foods. The Mediterranean diet has proven particularly beneficial. Also, pay attention to regular meals to prevent extreme blood sugar fluctuations.
Can popular diets like low carb or intermittent fasting help prevent type 2 diabetes? Dr. Alexandra Schoeneich: "Low carb to moderately low carb diets can be effectively used in preventing type 2 diabetes when applied correctly. Both forms can significantly lower long-term blood sugar and often lead to initial weight loss.
It is also necessary to pay attention to the selection of natural foods, complex carbohydrates, unsaturated fatty acids, etc. Intermittent fasting (16:8) can also be useful for the prevention of type 2 diabetes. However, it also depends on which foods and how much of them are consumed.
For example, if consumption mainly consists of processed, high-fat, and sugary foods or if a calorie surplus is generated through consumption, these dietary forms will not be preventive either."
"Stress and lack of sleep promote the release of sugar from the liver by releasing adrenaline, noradrenaline, and cortisol, and inhibit the effect of insulin on the cells. For this reason, blood sugar levels increase overall," says Dr. Alexandra Schoeneich. Important: develop individual strategies for coping with stress, such as meditation, yoga, autogenic training, or simply regular breaks in everyday life. Getting enough sleep is just as important – ideally seven to eight hours.
Have your blood sugar checked regularly, especially if you belong to a risk group. This includes people who are overweight, have a family history, are over 45 years old, and women who had gestational diabetes during pregnancy. An early diagnosis of prediabetes – a precursor – enables timely countermeasures.
Large-scale studies and meta-analyses confirm that various dietary approaches – from plant-based to Mediterranean to low-carb – have positive effects on metabolism, blood sugar levels, and complication risks. Programs that support people in practical implementation, such as the Diabetes Prevention Program in England, have measurably reduced the development of diabetes in national health data sets.
The higher the individual risk – for example, due to prediabetes or hereditary predisposition – the more comprehensive the preventative measures should be implemented. Modern risk scores help to more accurately determine personal diabetes risk and to specifically counteract it.
Type 2 diabetes can be prevented in most cases through timely and consistent lifestyle changes. A healthy diet, increased physical activity, avoiding nicotine, and maintaining a normal body weight are the scientifically proven cornerstones of effective prevention. For people with increased risk, medical consultation and an individually tailored prevention plan are particularly recommended.