Last week, the American Medical Association voted to classify obesity as a disease. But is being fat the same thing as being sick?

The decision came at the annual meeting of the American Medical Association (AMA).

Though a committee of experts recommended against classifying obesity as a disease, the association's delegates voted to approve the change.

And at a stroke, a third of the US population became diseased.

The immediate repercussions of the vote are not clear - while insurance companies may now be more inclined to cover obesity prevention and treatments, they are under no obligation to do so.

AMA president Ardis Hoven says the new designation will increase the focus on obesity treatment and prevention, and in doing so help medical professionals deal with the increasingly complex health problems associated with being overweight or obese.

RESOLVED, That our American Medical Association recognise obesity as a disease state with multiple pathophysiological aspects requiring a range of interventions to advance obesity treatment and prevention. The approved measure as voted on by the American Medical Association

Though obesity has been a health issue in the public eye for decades, doctors are not always equipped or prepared to help patients treat and prevent obesity-related illnesses.

Hoven says the vote will encourage doctors to change that, and will provide more training and education for both doctors and patients.

"When we are sitting in the examining room and talking about things to prevent weight gain and promote weight loss, what this is going to enable us to do is put together tools and teaching and education around better ways to impact patient responsiveness around our concerns about their obesity," she says.

For Americans who went to bed feeling fine and woke up with a disease, the new designation is alarming.

"Pretty uniformly people are not real happy about it," says Lesley Kinzel, senior editor at the website XOJane.com and author of Two Whole Cakes: How to Stop Dieting and Learn to Love Your Body.

Soon after the announcement of the decision, the hashtag #IAmNotADisease became popular on Twitter for those wishing to express their dismay with the decision.

Kinzel says that many fat people already have trouble accessing proper healthcare, because their ailments are not taken seriously except as an extension of their weight.

"You might go to the doctor with a twisted ankle or a head cold and be told you need to lose weight, which doesn't help with the twisted ankle or the head cold," she says.

She worries this classification will only make the problem worse.

Image caption New Jersey governor Chris Christie recently underwent weight-loss surgery

"It says that a fat person is inherently sick, and in need of special treatment for this visible sickness," she says, noting that at least a third of people who are classed as obese don't have any increased risk for diabetes or cardiac problems.

"It makes me worried that doctors are going to be less able to listen to patients."

What is obese? The Body Mass Index (BMI) looks at a person's weight divided by height, squared. A BMI over 30 is considered obese. It often labels muscle-heavy professional athletes as obese, while classifying as "average weight" those who may have a slim frame but percentage of dangerous body fat. Calculate your BMI What are the health risks of obesity?

On the other side of the debate, some worry that classifying obesity as a disability removes an element of personal responsibility.

"Are people going to start taking off work and claiming disability because they are obese? If restaurants are offering [high-caloric] items on the menu, does that open the door for people to sue?" asks Judy Gaman, a health and wellness consultant at Executive Medicine of Texas.

"When you take personal responsibility out of the equation, it opens the door for a lot of other things."

Marlene Schwartz, the acting director of the Rudd Center for Obesity and Food Policy at Yale University, says that calling obesity a disease could allow for obese people who require medical interventions to get the help they need.

But she cautions that such a classification can lead to stereotypes and oversimplification.

Should a pill treat obesity? The classification of obesity as a disease comes as two new weight-loss drugs were approved by the Food and Drug Administration. The AMA hopes that the new classification will lead to even more new treatments for obesity, including medication. "Reclassifying this is going to encourage greater investment and research. It elevates the importance of necessary interventions," says Ardis Hoven, president of the American Medical Association. But for some, the idea of more pharmaceutical intervention is worrying. "The notion that obesity is a disease will inevitably invite a reliance on pharmacotherapy and surgery to fix what is best addressed through improvements in the use of our feet and forks," writes David Katz, director of the Yale Prevention Research Center. Where are you on the global fat scale? Read more in the Huffington Post

"To the extent that this helps people get the resources they need and convinces insurance companies that funding prevention is better, I'm all for it," she says.

"To the extent that it makes people feel badly about themselves and increases stigma, I'm more cautious."

Obesity, she says, is incredibly complicated. The idea that those with a Body Mass Index over 30 - the official mark for obese - just need to put down the hamburger and pick up a skipping rope is reductive.

"The definition of obesity needs to take into account how complicated the issue of weight eating and physical activity is," she says.

She says a subset of those with a BMI over 30 are perfectly healthy, and that those who are not see a dramatic benefit from losing just 10% of their weight.

In those cases, a patient's health may change substantially, but their appearance and their BMI may not.

The designation of obesity as a disease, she says, has tremendous potential to help harness resources and direct attention to the potential health issues of those with a BMI over 30.

Used correctly, she says, the new classification should fight stigma.

"We need to be able to use this disease label to the extent that it makes people take obesity seriously, and not keep blaming people for being irresponsible," she says.

In the end, she says, everyone involved in this debate wants the same thing - for all Americans to enjoy nutritious food, physical activity, good health, and to feel comfortable with their bodies.

Whether this new classification will help with that mission that remains to be seen.