Salt in Saltwater, Brain Calories

Hey, Matt: My son and I were at the beach and he suddenly asked me a question that I couldn’t answer. I figured maybe you could. So, to make my son (and me) a little smarter, please tell us why the ocean tastes like ­salt. — Dad and Son, via email

You’ll be ready to take on the neighborhood when I’m through with you. Schedule a block party, then knock ’em silly with all these facts: water on our planet travels in a great, huge circle; it evaporates from wet places, goes up into the sky and condenses, then comes back down as rain, which runs off the land back into the streams, lakes, rivers, and oceans, where it evaporates again. Okay so far? So, anyway, rain is slightly acid, even without our help, and as it falls into lakes and streams it erodes rocks and strips off ions of various mineral salts, including sodium chloride (table salt). Eventually most of the rainfall ends up in the oceans. Most of the mineral ions are sucked up in the evaporation, but some is left to build up the seafloor. And most of the sodium chloride just sits there in the ocean making things taste ­salty.

Another source of chloride is the volcanic vents in the ocean floor, which spew hydrochloric acid. Most of the sodium comes from the ­rocks.

This process has been going on for eons. So, why doesn’t the ocean just taste saltier and saltier? Enough of the sodium chloride is used to build the sea floor to balance out what is dumped into the ocean from our rivers. The water you taste in a stream is the same water that ends up in the ocean, it’s just that it’s been evaporated in the ocean. I don’t know how old your son is, so you might have to simplify things a little. But the elves and I are happy you’re both a lot smarter. That’s our ­goal.

Matt: I’ve got to lose some weight, but I really don’t like exercise very much. But I know we burn up some calories just walking around and stuff so I thought maybe I could make up a new diet that lets you stay in bed but think real hard about stuff and burn up calories that way. Do you know how many calories we burn up when we think? Has anybody ever figured that out? It takes energy to think, so it must use up some calories. If it’s enough then you could probably stay in bed and lose some of your beer gut. Help me with ­this. — Wayne B. via email

Crack a Bud and take a trip with us to the land of metabolism, Wayne. Some scientists with a lot of time on their hands, apparently, actually have figured out how many calories our brains burn. Now, there might be a difference if you’re thinking about whether Jessica Simpson is sort of a skank or the skankiest of all or doing calculus in your head. I know the scientists used a lot of mice in their research, so I’d guess we can figure it was more at the Jessica Simpson end of the ­scale.

Consider mice under ane sthesia. Whatever is going on in their rodent brains burns only 6 or 7 calories an hour. Whipping out their calculators, the science guys figured that just keeping yourself conscious, with no muscle movement, will burn about 240 calories in 24 hours. But if you want your Thinking Man’s Diet to involve heavy-duty brain activity, we can add a puny 5 calories an hour to that. Assuming you can concentrate that hard for that long. Why am I suspicious? Anyway, one group of researchers found that smart people burn more brain calories than idiots do. Why are we not surprised? And thinking about something deep or difficult requires more calories, but not enough to help you with your diet plan, ­Wayne.

Another bit of wisdom we can pluck from the busy science-guy brains is that gray-matter activity consumes only about 20 percent of our daily calorie intake, and most of that is required for automatic processes of walking around and seeing. So, our brain muscles just aren’t good candidates for weight-loss ­exercise.

But, hey, Wayne, crack another cold one. I have some other ideas that might help. Shooting pool takes 160 calories an hour. Laughing? Forty an hour. Passionate kissing? About 20 calories a minute. If you can sleep for 24 hours, you will have burned about 1800 calories, your basic calorie requirement, assuming you’re about 150 pounds. Some science guys have different figures for these activities, based on their own research, but this is a nice average for you. We’ll leave you with this: I hate to tromp on someone’s dream, but you might want to rethink your diet scheme. But then consider all the calories you’ll burn while you do ­it.

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