MORE: How Much Sugar Are You Really Eating Everyday? Australian actor and director Damon Gameau decided to find out—and chronicles the results in his new documentary, That Sugar Film (opens in select US cities July 31 and available on iTunes; learn more at thatsugarfilm.com). For 60 days, Gameau abandons his Paleo-style diet for one that packs 40 teaspoons of added sugar per day, the amount that mirrors the intake of most Australians. The twist? None of the sugar can come from expected sources like candy, cookies, or other treats. Instead, Gameau has to get all of his added sugar from packaged foods that are widely considered to be good for you. Think cereal, granola bars, fruit juice, flavored yogurt, frozen meals or any of these surprising foods that list sugar as the first ingredient. The story that unfolds feels a lot like 2004’s Super Size Me: Gameau enlists a cadre of experts to track his weight, cholesterol, liver function, and more. At the start, he’s healthier than average, and his docs all issue the usual warnings that his experiment isn’t just crazy—it could be dangerous. Exactly how dangerous, though, is anyone’s guess. Which is part of the reason why even though you sort of know how this story’s gonna end, you can’t stand to look away while Gameau’s sugar-fed belly balloons at nearly the same rate as his pregnant girlfriend’s (who sticks to her clean eating ways throughout). Seriously, there’s no way you won’t cringe when you watch him dump spoonfuls of the sweet stuff onto a plain chicken breast—to illustrate just how much sugar is in a packaged chicken meal—and then taking a cloying, crunchy bite. MORE: 5 “Helathy” Yogurts with More Sugar Than a Doughnut And when you see the 17-year-old kid whose daily Mountain Dew habit means he needs to have 26 teeth pulled and wear dentures for the rest of his life, you kind of want to cry. Which is why, in the end, That Sugar Film won’t just leave you feeling really good about your own diet. It’ll leave you feeling sad, pissed off, and kind of shocked as to how Big Food still has so many people fooled about the garbage that they’re eating, and getting sicker and sicker as a result.