Well I am considered morbidly obese at my weight of 270 pounds. However I have low cholesterol, no high blood pressure and no heart problems and considered in very good health.
My husband however, works out constantly, has 6 pack abs, a great bod at 170 pounds and is also a diabetic with high cholesterol.
Therefore, I dont think its your weight that makes you unhealthy, I think its you as an individual.

Granted there are many factors to consider when one says they are "healthy". Does that mean that you feel well, that you're rarely ill, or that the Dr. says your BP is normal, or a lab test is within the normal range? The term "morbid" is linked to the word "obese" because it is strongly correlated to illness and poor health, possibly death. Although you may feel like your weight is not a health problem at this time, you can't see all the changes going on in your joints, in your blood vessels and organs. Fat tissue is highly active tissue in your body and a very high level of it is going to have an impact on your health. Health is on a continuum and is not a static thing. Sorry, I don't mean to be preachy or offend you, but the more you know about the human body and it's processes, the better insight you can have to health and the positive or negative effects of lifestyle on it. I am a nurse and everyday I see the consequences of lifestyle as well as genetics on peoples' health.

If you read any of the Dr. Oz books such as You On A Diet or You Staying Young, he breaks everything down in laymen's terms with great illustrations about what is going on behind the scenes in our magnificent bodies.