It's 1985. You're playing with your Rubix cube and watching a Lionel Richie music video on MTV. You go into the kitchen to pop some popcorn in your new microwave while you try to decide between drinking a Diet Coke or a New Coke. What you probably don't realize is that you are in the midst of the obesity epidemic's birth.

Scientists have long pointed at the "Big Two" reasons for the obesity epidemic — lack of exercise and the popularity of junk food. But now researchers are looking at other factors.

In examining health statistics, it's clear our country's weight gain started in the late 1970s. Since 1980, obesity rates for adults have doubled and rates for children have tripled, according to the CDC. The big question is why? What changed 40 years ago that made us so fat today?

That's what the scientific community so desperately wants to figure out. Some researchers say the answer can be found in high-fructose corn syrup, aspartame and fast-food restaurants, all of which were used much more heavily starting in the 1980s. But while these reasons make sense, there are others — like Ronald Reagan, microwaves, women's lib, air conditioning and smoking — that will make your brain hurt.

Despite all the confusion, I think one thing is clear — Ronald Reagan made me fat.

In 1980, Reagan deregulated much of the agriculture industry, which meant more food was being grown, which meant portion sizes increased. All of this is according to Marion Nestle, a professor at NYU and the author of The Politics of Food. I have to admit this convoluted association of cause-and-effect relationship reminds me of a really bad SAT question: Reagan is to portion size as penguins are to cheese.

And, clearly, that leads us to microwaves.

Jane Wardle, professor of clinical psychology at University College London, says obesity levels started to skyrocket after 1984, when more people began buying microwaves. The microwave allowed us to cook our food more quickly, leading to overeating of processed food made especially for the microwave. Making dinner went from an intentional, time-consuming process to "heat for 2 minutes."

And women's lib didn't help the situation, at least according to several anti-feminism
Web sites. At www.dumpyourwifenow.com, there's an article called "What Would Life Be Like Without Feminism" written by — I kid you not — Master of My Domain (I know, I thought it was all a joke, too. But these "men" are serious. It's so cute, like little boys forming a "girls are icky" club). It seems Master (hee hee) thinks that if women had just stayed home and cooked, no one would be fat. He doesn't seem to realize that the rate of homicide would have risen dramatically. I know how to use a shotgun.

Heating and air conditioning also might be to blame. When we get too hot or cold, we burn calories to warm up or cool down. But, like Goldilocks, when we find a temperature that's just right, our bodies get sleepy. Then we turn calories into fat. In the South, where obesity rates are the highest, homes with central air increased from 37 to 70 percent between 1978 and 1990, according to study in the International Journal of Obesity.

The same study also partially blames smokers for the epidemic. But not for the usual you're-killing-yourselves reason. Instead, the researchers said it's a known fact that smokers are skinnier. They also noted that smoking has decreased dramatically in the past four decades. The average rate of smoking was 40 percent in the 1970s, 32 percent in the 1980s and 21 percent today, according to a 2008 Gallup poll. How much did this impact obesity? The CDC estimates that between 1978 and 1990, 25 percent of the increase in overweight men and 17 percent of the increase in women was due to people who stopped smoking.

I think the implications here are clear. The obesity epidemic would be over if we all simply started smoking, stopped using microwaves, kept women in the home and turned off the air conditioning. And somehow, exhumed Ronald Reagan in order to un-elect him. We'd be living like it's 1950 — but we'd be skinny.

A pre-medical student at The University of New Mexico, Christine Barber has been a journalist in New Mexico for 14 years. Contact her at tlg@sfnewmexican.com or via her blog at etastesantafe.com.