Two important studies were released this week—a study from the Agency for Health Care Research and Quality on the rising rates of obesity in the U.S. and a New England Journal of Medicine study which found that total health spending for patients who received prescription drug coverage under Medicare Part D decreased.

While these two studies focus on different clinical outcomes, they serve as a reminder of where the health care reform debate began, where it should stay focused and what President Obama keeps reiterating: cost.

The Agency for Health Care Research and Quality study, “Trends in Health Care Expenditures by Body Mass Index (BMI) Category for Adults in the U.S. Civilian Noninstitutionalized Population, 2001 and 2006,” reports that obesity is linked to over 50 percent of the growth in spending per capita in the U.S. and the average annual growth in spending is 8.3% for obese adults compared to 4.9% for normal weight adults. Increased spending at this rate is unsustainable, especially since obesity is a key risk factor for a host of other chronic conditions, such as diabetes and heart disease.

The New England Journal of Medicine study, “The Effect of Medicare Part D on Drug and Medical Spending,” found that monthly medical expenditures (not including prescription drugs) were $33 lower in the group with no previous drug coverage and $46 lower in the group with a previous $150 quarterly cap. This shows that increased access to necessary disease management medication (“lipid-lowering and anti-diabetic medications”) can lead to lower overall health costs over time.

Both sets of data contribute to the growing body of evidence that proves that the key to reducing health care costs is disease prevention and management. This goes to show we have to reduce costs and expand coverage simultaneously. Congress is prepared to spend $1 trillion to cover the uninsured, but not $25 billion to reduce costs. That just doesn’t add up.