Following 'The Thin Commandments'

The documentary filmmaker bought a bike and started adding salads to his diet. Two months later he returned to the doctor and was pronounced perfectly healthy -- despite having lost only 6 pounds.

It's a journey that he chronicles in "America the Beautiful 2: The Thin Commandments," a follow-up to his first award-winning film. The documentary focuses on the United States' unhealthy obsession with dieting and losing weight.

"We have a health problem, not a weight problem," Roberts says matter-of-factly.

CNN spoke with Roberts about his film, why he believes the BMI system should be outlawed and the award he's most proud of. The following is an edited version of that interview:

I always had this knack for attracting really awesome, quality women in my life. Like I had a five-year [relationship], a five-year and an eight-year relationship. [But] I used to travel around the country with these athletes and entertainers, running into these women that would hang out at the gate.

After doing that for a while, I went, "Wow, you know what? I want a girlfriend that's awesome like the one I have, but that looks like these [groupies]." After being exposed to them for so long I could no longer appreciate the awesomeness of the woman that I was with. So that's when I started thinking, "Why did I do that?" Like when you have so much, why was beauty so important? That gave me the idea to do a documentary.

I was sitting around watching my film one day and it occurred to me -- it just hit me -- all these three things: plastic surgery, cosmetics and eating disorders, are things that primarily affect women. And we still have an archaic appreciation for women in our country because if things primarily affect women, nobody does anything about it. But when it affects men, they do something about it right away. ... It's like we're in 1910. Everything looks really sophisticated because you have computers, you have iPads, you have smartphones and tablets, and everything you see looks so developed, but underneath it, I don't believe we value women the way that we should in this country.

When I was traveling with the first film, I went to 287 universities. At each one ... somebody would stand up and say, "Wow, we really like your film, but you didn't deal with the dieting industry. Why not?" So I go on the computer one night just researching dieting, and I come across this website that has the BMI, body mass index, of celebrities. So according to this website, the BMI of Tom Cruise, Will Smith, Mel Gibson, The Rock, Christian Bale, LeBron James -- all these celebrities -- make them either overweight or obese. And I'm like, "This is the most ridiculous thing I ever heard."

So then I did some more research on BMI. The government uses it, doctors use BMI, schools use BMI, and I'm like, "This is how they get you." In the first film, I show how we use beauty as a weapon against the American public -- now we're using weight as a weapon against the American public.

It was invented in like 1830 ... and it was invented to show sizes of populations. Like, for instance, the entire population of the United States. It was never intended to be used for an individual diagnosis of someone's health and how much they should weigh. That came in the 1970s with this guy Ancel Keys when he reformulated it to the current BMI thing.

Then in 1998, some of the scientific advisers of Weight Watchers went to the government and said, "Hey, you know what? The number that's used for the overweight category for BMI should be lowered." And the government did it. They lowered it. And when they lowered it, literally 25 million people became overweight, overnight. But guess what: Those are new customers now for the dieting industry.

First off, because [if] you are defining [obesity] by BMI, then it's erroneous. So what we may have as a problem in this country is a health problem. That I agree with. We show it in the film. We have a health problem. And what we also show in the film is that health problems come to people with or without weight. So the film is making the point that we should be focusing on the health of people and not their weight.

Where we have problems is lifestyle choices. We have too many people eating fast food. We have too many people not exercising. We have too many people not engaging in healthy lifestyle behaviors. My point is if we have more people engaging in healthy lifestyle behaviors, we will become a healthier nation, whether we lose weight or not. If you think about it -- it makes sense, right?

So far I've done the health and beauty series, so the next one will complete it and make it the health, beauty and sex series, which are the three biggest things affecting our youth. It will be about the sexualization of our youth. Everyone says that's going to be the whopper there. I'm going to start it in January. I have no idea what I'm going to find. I always start my documentaries with no preconceived notions, and I jump in interviewing people to see what I can find.

There's a film festival that Will Smith and Meryl Streep are affiliated with -- the Giffoni Film Festival. It's a film festival for kids. They never show documentaries, only feature films that appeal to kids, right? But with ["America the Beautiful"], the Giffoni Film Festival made an exception to let a documentary in there. I went to the screening, and I was terrified that my film was going to put all these kids in a comatose state. We went to the awards presentation, and they announced the audience award and called our name. I went into shock. Here are kids voting a documentary as their favorite film in this big film festival. That was literally my proudest moment.

[It's] actually touring around the country in theaters. We've been to six cities so far; we'll go to 30 more. They can go to our website at AmericatheBeautifuldoc.com and go to the screening schedule and see when we'll be coming to a city near them. It [also] comes out on DVD in March.