One way you can get Asthma is for example either working in a heavy industrial place ( like a coal refinery) or living in a place that has very high pollution you would usually develop it at a young age. Type II diabetes you usually develop either from it already been in your family blood line. Or from eating very fatty foods from a young age. Or just being very overweight for a long amount of time. You can develop Cancer from working in heavily radiated workplaces without proper protection. You can even get it if you have something in your genes that just makes you more susceptible. And you can get Cardiovascular Disease from eating to much red meat or too much fat filled food. Or not being physically fit ( don't need to be overweight). Sorry can't help you with Osteoarthritis.
Hope this helps!
