Millions of Americans have taken a look at the costs of the new insurance options they have under the Patient Protection and Affordable Care Act, also known as Obamacare. Many of them haven't been happy with what they've found, as in many states, premiums will go up versus what people were paying before for individual health-insurance coverage. A recent study from the Manhattan Institute took a look at premiums across the country to figure out which states would end up seeing the biggest increases.

In the following video, Dan Caplinger, The Motley Fool's director of investment planning, looks at the results of the study and finds that in five states, premiums under the Affordable Care Act are slated to more than double. Dan runs through the five states, noting that in Nevada and Arkansas, the increases will hit young men the hardest according to the survey. Meanwhile, New Mexico has rates that double across the board for both young, middle-age, and older residents. Vermont has age-neutral premiums statewide, but in North Carolina, the rate increase actually hits older residents disproportionately hard.

Dan goes on to discuss the potential impact on health insurance companies UnitedHealth (NYSE:UNH), WellPoint (NYSE:ANTM), Cigna (NYSE:CI), and Aetna (NYSE:AET). In general, the more high-deductible, low-benefit catastrophic policies any particular company wrote in a given state, the bigger an impact Obamacare will have in preventing those insurers from offering catastrophic policies to customers who preferred them. Only if those people go ahead and get higher-quality coverage will insurers have a chance of recouping lost business.

Fool contributor Dan Caplinger has no position in any stocks mentioned. The Motley Fool recommends UnitedHealth Group and WellPoint and owns shares of WellPoint. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.