Yes, we have fragile, finite bodies. Our organs will wear out eventually, our hearts will become week, our lungs less elastic. Our livers will filter our blood more slowly and less effectively, our kidney will stop working eventually. Any of these organs will fail more quickly if we mistreat our bodies. It is a part of life, and hospitals are full of people who are facing this reality.
Do you know what the first thing a doctor is going to tell a patient when they are diagnosed with High Cholesterol, High Blood Pressure, or Diabetes is? They are going to tell them about the diet and lifestyle changes they should make to control the disease. Obesity is one of the greatest risk factors for disease in the US. Losing weight and eating a better diet would do more for most people with type II diabetes and high blood pressure than better insurance would. Drugs are helpful, reversing the damage you have done to your body is better.
Making insurance more expensive doesn't help people. Requiring healthy people to buy insurance creates a slightly large pool of money to treat the ill, but it doesn't actually significantly improve the condition of people who don't need regular health care. Telling people, people of sound mind, that the government knows their needs better than the do doesn't help people.