According to the Robert Koch Institute (RKI), life expectancy in Germany is rising and the general health situation is good, but the number of people who smoke, are too fat, take too little exercise and/or drink too much alcohol is still too high. 53 percent of women and 67 percent of men in Germany are overweight, and researchers are concerned about a rise in obesity.

When we refer to overweight and obesity we are referring to abnormal or excessive fat accumulation in the body that may impair health. To find out if an adult is overweight, the weight of the person in kilograms is divided by the square of the person's height in meters (kg/m2). For most people, the result, also referred to as Body Mass Index (BMI) of 18.5 and 24.9 is considered healthy. According to WHO, a BMI greater than or equal to 25 is overweight and a BMI greater than or equal to 30 is obesity.
In a report compiled by the Spiegel earlier this year, cremations in Germany are becoming more complicated owing to an increase in obesity. Around half of the country's deceased are cremated. In January, the fire brigade had to be called to put out a fire in the western German town of Hamelin after a body weighing over 200 kilograms (440 pounds) burned for over 15 minutes, with flames shooting out of the crematorium's 10 meter (33-foot) high stainless-steel chimney, and parts of it beginning to melt. Firemen established that the smoking chimney was glowing at 600 degrees Celsius (1,100 degrees Fahrenheit), and it took four hours to reduce the body in the furnace to ash.
According to the WHO, overweight and obesity are the fifth leading risk for global deaths, with at least 2.8 million adults dying each year as a result of being overweight or obese. A high BMI is highly responsible for up to 23% of cardiovascular diseases, musculoskeletal disorders, 44% of diabetes and between 7% and 41% of some cancers (breast, colon and endometrial). Overweight and obesity is mainly caused by a lack of energy balance, meaning the energy one consumes is not equal to the energy one expends. We are not talking about calculating this balance on a daily basis, for it is the balance over time that helps maintain a healthy weight.
Obesity is caused by poor eating habits, for example eating over-processed foods with high fat content, drinking too much, eating more than enough, or failing to include vegetables, fruits and fibre in your diet. Some hormone problems may cause overweight and obesity, such as under-active thyroid (hypothyroidism). Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone. Lack of thyroid hormone will slow down one's metabolism and cause weight gain. This also makes one tired and weak. Some medicines like corticosteroids, antidepressants, and seizure medicines may cause one to gain weight. The older one gets the more muscle one loses, especially if one is less active. Muscle loss can slow down the rate at which the body burns calories. Thus, if one does not reduce their calorie intake as they get older, weight gain may not be avoidable.
Overweight and obesity tend to run in families. Chances of being overweight are greater if one or both of a person's parents are overweight or obese. Some people tend to stay the same weight for years without much effort, whereas others find they put on weight quickly if they are not careful about what they eat. This could be as a result of one's genes. Moreover, children adopt the habits of their parents. A child who has overweight parents who eat high-calorie foods and are inactive will likely become overweight too.
Studies have confirmed that the less people sleep, the more likely they are to be overweight or obese. A team of researchers from the LMU (Ludwig Maximilian University) led by Professor Till Roenneberg has now shown that a discrepancy between internal time and the demands imposed by school and work schedules and leisure stress contributes to obesity. The LMU chronobiologist coined the term "social jetlag" to describe the phenomenon. According to the researchers, if the rhythms dictated by our lifestyles are persistently out of phase with our biological clock, the risk of illness, such as high blood pressure and even cancer, rises. In persons who get too little sleep, the perception of hunger is perturbed, often leading to overeating. Thus, social jetlag shows a significant association with increased body-mass index (BMI).