Part II – Metabolism and Detox
Recall that you, Janine, and Mitchell were talking about the high-protein, low-carb diet that Mitchell decided to go on. Now you’re sitting down to lunch with the pair again. While you still don’t have a full answer for them, the conversation turns to diets again.
“What is that green glop you’re drinking?” Janine asks, staring at a cup that Mitchell is holding.
“It’s this great new herbal detoxifier that I found at the health food store,” Mitchell says.
“Detoxifier?” Janine asks. “What the heck is a detoxifier?”
“Obviously you’ve never studied dieting,” Mitchell says, with a superior air. “You see, if you eat a lot of junk food like some people do”—here Mitchell gives the evil eye to Janine’s milkshake and pizza—“you get all these toxins building up in your cells. That changes your body’s set point for fat. If you don’t get those toxins out, especially out of the fat cells, your body can’t get rid of fats. So if you drink herbal detoxifiers like this, you get rid of toxins, and then you can raise your set point and rev up your metabolism so that you lose a lot of weight. I just started this and I dropped like two pounds in a day.”
“Two pounds?” Janine asks. “Do you have the container? Let me see the ingredients.”
Mitchell digs into his back pack and pulls out a plastic canister of green powder. Janine reads the label.
“Ah hah!” she says. “Just as I thought. Parsley, dandelion, green tea—those are herbal diuretics. You’re not losing fat, my friend. You’re just losing water. That can be dangerous, you know. Too much diuretic can mess up your system.”
“But it says it flushes fat from your body,” Mitchell protests. “Look, right there on the label.”
Janine gives him a patient, though pained, look. “Have you ever noticed an oil slick in the toilet after you’ve used it?”
“Um… no?”
“Then what exactly does ‘flush fat’ mean?”
“Um, maybe it makes it break down or something?”
Janine shakes her head. “You’re drinking the stuff and you don’t even know what it’s doing to your body.”
“Look, all I know is that it works,” Mitchell says. “I believe in this stuff.”
“Believe all you want,” Janine says. “It’s still a crock. And I still don’t see why you think you need to be on a diet to lose weight. Eating healthy, yes, but losing weight? You?”
“I just really feel fat sometimes,” Mitchell mumbles. “I look in the mirror at gym class and all these other guys look so buff. And there’s Steve in my dorm who keeps poking me in the stomach and yelling ‘marshmallow!’”
Janine nods in understanding. “Maybe all you need is a little more exercise to tone up. But really, Mitchell, you’re on the thin side. Maybe you have a body image thing going here.”
“What do you think?” Mitchell asks, handing you the canister of green powder. “Isn’t there something to the idea of detoxifying the body? Isn’t set point a real thing?”
“Tell him all he really needs is to eat healthy foods and get a little exercise,” Janine says. “Muscles use up lots of calories, so the only way to increase your metabolism is to gain some muscle. This green glop is going to drain his wallet and make him sick.”
Questions
Find out how the medical community defines “obesity.” What factors contribute to obesity?
What is “set point theory”? Are toxins involved? Describe how body size and homeostasis are related.
What is “metabolism”? What does human metabolism have to do with energy balance and body weight?
Janine said that increasing muscle mass increases metabolism. Is she right? If so, how does this work? If not, why not? Check a biology textbook for information on the structure of muscle cells for clues.
Mitchell said that the herbal product “detoxifies” the body. Janine said it’s a diuretic. Find out what a diuretic is and what effect it has on the body. How does its action affect homeostasis of fluid balance?
What body systems remove toxins from the body? What are “toxins,” and where do they come from? Are all “toxins” alike? Do toxins really cause you to gain body fat or prevent you from losing weight?
Body image and dieting go hand-in-hand. When body image is distorted, people can diet to excess. Do you think that Mitchell has a body image problem? What further health problems can result from a body image problem?
Resources
- Set Point Theory (MIT Medical):
- http://medweb.mit.edu/pdf/set_point_theory.pdf
- WebMD article on detox diets:
- http://www.webmd.com/food-recipes/features/detox-diets-purging-myths
- BBC news article on detox diets:
- http://news.bbc.co.uk/2/hi/health/7808348.stm
- National Institutes of Health information:
- http://health.nih.gov/topic/WeightLossDieting
- http://health.nih.gov/topic/EatingDisorders
Originally published at http://www.sciencecases.org/atkins/case2.asp
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