Nutrition

Nothing's perfect, right? That includes things that are good for you, like superfoods. I've written a few articles (and even a book) on superfoods; mostly glowing accounts of their nutritional value and potential health benefits. Those are all true and good things, of course, but there are also some possible unusual side effects you may encounter when you consume large amounts of some of these foods. They're harmless, but they might make you say, "ick" or in the case of a couple of them, scare you a little bit.

Asparagus Pee

Asparagus contains sulfurous chemical compounds that give your urine an unusual odor. It doesn't happen to everyone, but it's fairly common. It happens quickly, too, so if you've eaten asparagus and you haven't smelt something funny the next time you peed, you're not one one of the lucky ones who have this reaction. Aside from the unusual odor, asparagus is good for you. It's low in calories, high in fiber, iron, folate, and vitamins A and C. It's even possible the compounds in asparagus can help your liver breakdown the byproducts of drinking too much alcohol -- as long as you eat the asparagus before you go out drinking. Here's a lengthier description of asparagus pee.
Green Leafy Poop

Spinach and kale are two fabulous superfoods because they're rich in vitamins, minerals, fiber and a bunch of phytochemicals that may have health benefits. If you eat lots of them, you'll also have green stool. It may be more common if your "transit time" is too quick and the greens aren't digested properly. It might scare you the first time you notice it, but it's rare for green poop to be due to any type of health issue. It's the other colors you may need to worry about. Amber Tresca, our Inflammatory Bowel Disease Guide at About.com, has the scoop on colored poop.
Red Beet Pee

Yeah, I know there's kind of an excretory theme here. If you eat a healthy helping of beets, you might notice red or pink urine later on that day or the next. This can be horrifying because it looks like blood, and peeing blood is never a good thing. Red beet pee is harmless and it actually has an official name: beeturia, which I think sounds like a good name for a Pokemon. Red urine isn't a reason to give up on beets. They're low in calories, high in vitamins and fiber, plus some of those red pigments may have some health benefits. Peggy Trowbridge Filippone, our Guide to Home Cooking here at About.com, has everything you need to know about choosing and cooking beets.
Garlic BO

Garlic makes almost all the superfoods lists and there's a ton of research on it's health benefits. It can help reduce cholesterol, and aid in controlling high blood pressure. Some people believe it helps prevent several forms of cancer as well. The thing is, if you eat lots of garlic (or take some garlic supplements), you're probably going to suffer from garlic induced body odor. It's probably due to your body's unfortunate reaction to allicin, the active chemical found in garlic. Dr. Cathy Wong, our Alternative Medicine Guide, has the lowdown on garlic. (Did you notice I didn't make any garlic vs. vampire jokes?)
Carrot Skin

Carrots are rich in carotenes, which are substances related to vitamin A. They're found in the orange pigments and are good for you, but, if you eat lots and lots of carrots, you can develop a yellowish or orange cast to your skin. It's mostly noticeable on the soles of your feet and the palms of your hands. If you've every seen "sunless tanning pills," they're probably just high dosage beta-carotene pills. You won't get tan, you'll turn orange. Officially this condition is called carotenemia and it's most common in children, since they're little (don't worry -- it's harmless). Dr. Vincent Iannelli, our Guide to Pediatrics, has the details on carotenemia.
I guess I could also give an "honorable mention" to legumes and cruciferous vegetables like brocoli, Brussels sprouts and cauliflower. They're all good for you, but their high-fiber contents can also lead to potentially massive bouts of flatulence.