Obesity, caused by dietary factors and physical inactivity, is probably the greatest scourge that future generations will face. In most societies, levels of physical activity have dramatically declined. International recommendations for minimum exercise requirements (at least 150 min of moderate exercise per week) only appeared in most countries at the beginning of this century. But are these guidelines too lenient? Beyond reducing and preventing obesity, physical activity has a myriad of benefits for people of all ages. Only certain types of saturated fatty acids—in particular, even-chain fatty acids that are associated with intake of carbohydrates and alcohol—are positively associated with incident type 2 diabetes. Food type, not just food volume, can be a cause of obesity and diabetes. People should be given all necessary encouragement and opportunities to follow these guidelines as a minimum requirement for good health. Children should grow up with the knowledge that eating a good diet and being physically active is the norm, not the exception. How essential is Physical activity and good diet to prevent type 2 diabetes in children?