BY STUFFING HIS FACE with Big Macs and practically killing himself in the process for his documentary “Super Size Me,” Morgan Spurlock became the anti-fast-food poster boy. His FX series “30 Days” uses a similarly immersive method to explore other parts of American society, often touching on the health aspects of various lifestyles.

In season one, available on DVD ($27), he had an athlete try anti-aging techniques, got a mom to binge drink like her daughter and got city folks to live off the grid in an eco-village where they grew and ate their own organic food. The second season premieres July 26 at 10 p.m., and Express talked to him about the physical toll of his challenges.

» EXPRESS: Last season, you lived on minimum wage. How hard was it to eat healthy?
» SPURLOCK: I was really lucky. If I hadn’t had Alex [his wife] with me, I wouldn’t have eaten as well as I did. We were only spending $40 a week on food, and when I’m in New York, I spend $10 on just a lunch. But she was cooking and it was healthy food — beans and rice, fresh vegetables. It was kind of a Third-World diet, but it was good and hearty. If I’d been on my own, I would have spent more money on stuff in cans that I could just reheat. I was working two jobs, so when I got home, I was thinking, “What? Am I going to cook something now?”

» EXPRESS: Did you ever consider going to McDonalds?
» SPURLOCK: Not one time ever. For me, I couldn’t handle even the idea of grabbing something off of the dollar menu. I feel that a lot of the people who eat this food fall into the idea that it’s too hard to cook. So, I was really fortunate.

» EXPRESS: And this season, you went to jail.
» SPURLOCK: Where the food was fantastic. … You’re eating food loaded with carbs, a lot of breads and potatoes. Because they just want to tie you over to the next meal. It’s not based on any nutrition. The prison spent an average of 69 cents per inmate per day on food.

» EXPRESS: Anything about it you liked?
» SPURLOCK: I liked leaving.

» EXPRESS: How about exercise?
» SPURLOCK: Where I was in jail, they get to exercise one day a week for an hour. I would walk around the day room, and 35 laps is a mile. So I would do that a few times a week, along with push-ups and sit-ups. Anything to stay active.

» EXPRESS: When you prepare for these challenges, how concerned are you about your health?
» SPURLOCK: I’m concerned every time. I read and study a ton. But the most important thing for me is to stay in the best physical shape possible. If I don’t, I get depressed and I’m not on the top of my game. If I’m feeling good, I can take in more of what’s happening.

» EXPRESS: What do you do to stay in shape regularly?
» SPURLOCK: I ride a bike, run. I hike in the mountains.

» EXPRESS: And you eat a lot of hearty vegan fare?
» SPURLOCK: I do when Alex likes to cook. She’s not so much on the cooking right now because she’s pregnant. But she’s getting over the nausea stage, which is good.

» EXPRESS: So you’ve been doing the cooking for her?
» SPURLOCK: I have a little bit, but she doesn’t want anything right now.