Mood swings, weight gain, and early stage fatty liver disease. What caused all of these problems for Australian director Damon Gameua – and did so in just a few weeks? Sugar. 40 teaspoons of it today, a bit more than a typical teenager eats.

The sugar did not come from likely sources, like soda or chocolate. Instead, Gameua went for seemingly health foods like “low-fat yogurts, and muesli bars, and cereals, and fruit juices, sports drinks... These kind of things that often parents would give their kids thinking they’re doing the right thing.” He did so for his upcoming documentary, That Sugar Film, with the intention of sticking to the diet for 60 days.

Here are some of sugary foods that you might think are good for you.

1. Breakfast cereal: This all-American breakfast can be more than 50 percent sugar, by weight. Kellogg's Honey Smacks, for example, is a whopping 56 percent sugar. Options lower in sugar are Rice Krispies, Crispix, Corn Flakes, and Cheerios - but maybe not the Honey Nut kind.

2. Yogurt: Yes, this oh-so-healthy food can be oh-so-full of sugar. A six ounce plain Dannon yogurt has 12g sugar, all from naturally occurring sugar in the milk. Switch to fruit-on-the-bottom strawberry and you get double the sugar, now from added sugar. If you're trying to stick to the recommended six teaspoons of added sugars per day (for women), this yogurt contains half of it.

3. 100% Juice: No, there isn't any added sugar. But drinking juice gives your body a sugar rush all the same, without any fiber to fill you up.

4. Granola Bars: An Oats 'n Honey Nature Valley Granola Bar comes with 12g of sugar.

5. Energy Bars: Pretty much, anything sweet and delicious that comes in bar form is chock full of sugar. Like a Chocolate Chip Clif Bar, with 23g sugar.

6. Tomato Sauce: 10g of sugar in one serving of spaghetti sauce.

7. Ketchup: Heinz Ketchup's top ingredient is corn syrup (sugar). And it's third ingredient is high fructose corn syrup (more sugar). A 20 calorie serving gets you 4g sugar.

8. Salad Dressing: 1g in a serving of Hidden Valley Ranch. 2g in Kraft Zesty Italian. 4g in Kraft Thousand Island dressing. That said, sugar usually isn't the biggest nutritional problem in salad dressing.