WHEN ERNIE HUDSON walked the red carpet at the premiere of Ghostbusters: Frozen Empire—40 years after he starred in the first Ghostbusters movie—the internet could not get over how buff he looked, and had all kinds of questions about how he maintains such a fit and youthful appearance at the age of 78. In the latest episode of Gym & Fridge, Hudson invites Men's Health into his Los Angeles home to break down the diet and training routine that keep him feeling good.

Firstly, Hudson is an intermittent faster, and won't eat before noon. His first meal of the day tends to be oatmeal, or smoked salmon and eggs. But while salmon is an almost-daily staple, you won't find many other varieties of fish or seafood in his fridge; he has a severe shellfish allergy. It's so bad, in fact, that it proved to be one of the most dangerous parts of his service in the U.S. Marine Corps.

"My drill instructor made me eat a piece of shrimp. I kept saying, I'm allergic! He couldn't believe that little piece of shrimp would be a problem," he says. "I ate it, and I had an awful asthma attack, and I was eventually discharged from the military."

Allergies and intolerances aside, there is not much that Hudson would 100% exclude from his diet. Similarly, he avoids fad diets these days. As he's gotten older, he mainly tries to keep moderation in mind.

"I don't have any rules of 'I don't eat.' When I make a rule, every part of me wants to break it, so I don't make rules," he says. "There's a price to pay for everything, and unless I really want to pay that price, it's best to just leave it alone... The problem with diets is, as soon as you get off them, the weight starts to come back. The toughest diet I ever tried was called the Beverly Hills diet; grapefruit, cottage cheese. It was stupid!"

"I think as I've gotten older, you realize that you're never going to do the things you know you should do," he continues. "You're never going to eat the way you should. I've done every diet you can imagine. At some point you have to just try to be a little bit better."

ernie hudson
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Hudson hits the gym three times a week, working out at Studio G Fitness, where he's been going for the last 25 years. "I'm not the kind of guy who can get motivated to work out," he explains. "I need someone else to tell me what to do."

He keeps his sessions to an hour or less, hitting strength, mobility and balance on different days, and on the occasions when he can't get to a gym, he'll make sure that he does at least 100 pushups.

"At a certain stage in life, it's just common sense stuff; I don't want to break anything, I don't want to overpush anything," he says. "You only get one body, so it's very important for me to keep it as functional as possible. Also, I've been married close to 50 years, and I don't want my wife pretending that I'm attractive. I want at least to have a smile when I take off my shirt!"