I'll throw my $.02 into the equation.
I work for a PA based Non-for-profit health insurance company ONLY available to residents in Central through Eastern PA and owned by a large hospital chain. Being that I technically work for both the medical side AND the health insurance side, I may have a more unique perspective than the layman or somebody not involved daily in the ins and outs of health insurance.
Specifically my profession is provider and customer relations as well as claims. I deal and see what is allowed for procedures as well as know how and what providers are paid for services and see what organizations are paid via Medicare, Medicaid, and Commercial sides.
My OPINION is that there are three MAIN (there are others, but these are primary) entities that drive up medical costs. Medical, Insurance, and Pharmaceutical with each one raising prices based on one or both of the others. So IMO, it's a problem of all three, not just the insurance or Medical side. Having profit in an industry is fine, but not when it's on the back of the sick, poor, and incapable of paying. It doesn't help anybody and puts more strain on government spending in the form of subsidies and benefits (not just Medicaid like everybody thinks). Just as Wal-Mart is a welfare king, supplementing it's workers with government benefits at our tax payer costs; insurance, medical and pharmaceutical are benefiting from government payments because the healthcare industry isn't sustainable as it's currently working.
My take, and I know it won't be popular, is that the medical side, insurance side, and pharmaceutical side are ALL over inflated and valued. They all live for and against each other and raise their prices and contractual agreements yearly in order to profit from one another. IMO, they're just inflating a balloon in the same aspect that the housing market values were over-inflated in 2007/2008. If things don't start having actually regulatory allowance adjustments for items like/such as Medicare/Medicaid allowances then without government help, nobody will be able to afford their insurance plans (especially considering inflation is stagnant, yet medical goes up from 5-10% YEARLY). The direct for-profit Medical system is showing it's incapable of regulating itself and pushing profits over medical care. Our system if very very flawed and I'd be willing to lose my job if it meant a sustainable health system was put into place instead.
My thoughts are a touch discojointed, but I'm sure my opinion is clear enough as indicated above. You can't blame everything on one of the three entities, without blaming the other two as well. Without one, the other two wouldn't be operating the way they are currently operating.