When is a nut not a nut?

When it's a coconut. Really. Well, almost.

The coconut is nut, I mean not, considered a "tree nut." According to US law (no kidding, there's a really a law about this) tree nuts include almonds, Brazil nuts, cashews, chestnuts, filberts/hazelnuts, macadamia nuts, pecans, pine nuts (pignolia nuts), pistachios, and walnuts.

Coconut trees are not technically trees because they don't have bark, branches or secondary growth (the process by which trees increase their diameter through the production of wood and bark). They are, believe it or not, perennials.

Which means those of you who are allergic to nuts (and/or peanuts) are not necessarily allergic to coconut. I bring this up because there's been a lot of chatter (from all those health-nut stringers who camp out in lawn chairs and follow these things) about the health benefits of coconut water. Low in fat, zero cholesterol, electrolyte rich, and more potassium than a banana — this stuff was even used in WWII and Vietnam as a substitute for IV solution. It's being touted as the best hang-over cure, the better "sports drink" drink, and all-round hydration champ.

Consider this: 8 fl oz of Gatorade has about 50 calories, 0g fat, 16g carbohydrates (13g simple, or 'added,' sugar), 93mg chloride, 36.6mg potassium and 95mg sodium.

8 fl oz of coconut water has about 50 calories, 0g fat, 10g carbohydrates, 283mg chloride, 705mg potassium, and 60mg sodium. It is also listed as a good source of vitamin C, riboflavin and calcium, as well as dietary fiber(!) and magnesium.

By the way, peanuts aren't nuts either. They're legumes. Don't get me started.