Celebrities and crazy diets go together like Madonna and exposed butt cheeks — not only are they big fans, but they go out of their way to make sure everyone else knows about it too. This time, however, the celeb diet of the day is just part of a larger diet trend: the mono diet.
Matt Damon recently shared in his Reddit AMA (ask me anything) that he used a mono diet of boneless, skinless chicken breasts to get gaunt for a movie role.
“I think the most challenging role that I’ve ever had, was when I did Courage Under Fire and I had to lose all the weight that I lost on my own,” he said. “I weigh probably 190 pounds right now, and I weighed 139 in that movie, and that is not a natural weight for me and not a happy weight for me even when I was 25.”
You know who else probably wasn’t happy then? Chickens. “I had to run about 13 miles a day, which wasn’t even the hard part. The hard part was the diet,” he said. “All I ate was chicken breast. It’s not like I had a chef or anything, I just made it up and did what I thought I had to do.”
A mono diet, as you can probably guess from the name, is a diet where you only eat one food. Not one type of food but simply one food, and nothing else. As far as simplicity goes, mono diets can’t be beat. They basically have only one rule: “Eat as much [insert single food] as you want and don’t eat anything else.” Mono diets usually last anywhere from a few meals to a few days to a few months. Upside: no worries about counting points or calories or forgetting your plan. Downside: everything else?
While Damon went with straight protein, two other mono diets are becoming incredibly popular these days: bananas (a la “Freelee the banana girl“) and potatoes (a la “the potato hack“). And a quick search shows that people have made mono diets out of nearly every kind of fruit or vegetable. Proponents of mono diets say they “cleanse” your body, kill cravings and help you drop weight easily and quickly — a feat I can believe as I imagine you lose the will to eat altogether within a few days.
But unsurprisingly, health professionals are concerned. First and foremost is the potential for abuse that comes with severe food restriction. Case in point: Pro-ana (pro-anorexia) sites dominate the top Google hits when searching for mono-diets. Then there’s the issue of proper nutrition. Substitute, say, grapefruits for your meals for a few days and you’ll probably be just fine, but if it becomes a long-term thing, you run the risk of becoming deficient in some vital nutrients and OD-ing on others.
“Eating mono-meals is totally disingenuous and wholly incompatible with digestion and health, ”cautioned Aidan Goggins, a HuffPo UK blogger and nutrition expert. “Optimum nutrient absorption and benefit in the body is only attained through the synergy of combining mixtures of foods in our meals.”
“For example, you can eat plenty of tomatoes but you will absorb minuscule amounts of lycopene (the nutrient we believe to be most beneficial in tomatoes). However, cook the tomatoes in a meal with olive oil and lycopene absorption increases drastically,” he explained. “Plant sources of iron are very poorly absorbed on their own. But combine them with a vitamin C-containing food and this problem disappears.”
Matt Damon, for his part, doesn’t have any desire to repeat the experience. “That was the most physically challenging thing I’ve ever had to do in my life,” he said, before going on to wax rhapsodic about his dream taco (ground beef and cheese in a crunchy corn shell, in case you’re curious).