“Coffee has organic acids that raise your blood sugar, raise insulin. Insulin puts a lock on body fat. When you switch over to green tea, you get your caffeine, you’re all set, but you will drop your insulin levels and body fat will fall very rapidly. [You will lose] 10 pounds in six weeks [if you replace coffee with green tea], I will guarantee it.”
This quote comes from Dr. Nicholas Perricone, specifically from a 2004 appearance on Oprah Winfrey’s talk show.
As with other doctors who are a staple on the media mogul’s program, Dr. Perricone is a source of nutrition soundbites that are TV-friendly, albeit not entirely accurate. Never mind, of course, that Dr. Perricone is a dermatologist who for many years was invited to sit on Oprah’s couch to dispense nutrition advice.
Let’s examine Dr. Perricone’s statements piece by piece.
“Coffee has organic acids that raise your blood sugar.”
True, coffee raises blood sugar levels ever so slightly. The same can be said about plenty of healthful foods — nuts, seeds, beans, fresh fruit, whole grains, and root vegetables. This concept of “raising blood sugar”, by the way, is nothing more than the glycemic index.
Additionally, if Dr. Perricone is so concerned about coffee’s glycemic index, why is he such a fan of wild blueberries, which raise blood sugar levels more?
“When you switch over to green tea, you get your caffeine, you’re all set, but you will drop your insulin levels and body fat will fall very rapidly.”
This, of course, assumes you are drinking coffee and green tea on their own, without any milk — dairy or otherwise — or sweetener. Add dairy, almond, soy, oat, or any other milk to your tea and your blood sugar will rise to some degree.
If you like your tea plain but accompany it with food (whether it’s oatmeal or a chocolate chip cookie), this talk of “dropping insulin levels” also becomes a moot point.
The above statement also makes the erroneous assumption that weight loss is simply about dropping insulin levels, rather than lowering caloric intake.
It is absolutely possible to lose weight while eating foods with high glycemic indeces, provided that calories are also being lowered.
Allow me to clarify. It is true that plenty of fiberless and overly processed foods — white flour, white sugar, refined grains — raise blood sugar levels significantly.
However, fruits are far from low-glycemic. In fact, ice cream has a lower glycemic index than watermelon. If weight loss was your goal, would you consider a cup of watermelon or a cup of Ben & Jerry’s to be the wiser choice? Not to mention — have you ever heard of anyone gaining weight as a result of drinking unsweetened black coffee?
Remember, too, that a food’s glycemic index can be altered by a variety of factors. A potato’s glycemic index, for instance, is different if you eat it with its skin and top it with olive oil than if you peel and mash it.
“[You will lose] 10 pounds in six weeks [if you replace coffee with green tea], I will guarantee it.”
If this were a money-back guarantee, Dr. Perricone would have to file for bankruptcy.
The notion that all it takes to lose 10 pounds — in six weeks, no less! — is a switch from coffee to green tea is not only science fiction, it is also infuriatingly misleading. Talk about setting people up for failure.
Of course, this “promise” wasn’t met with an ounce of skepticism. Oprah vouched that she would give this a try, and the audience responded with applause. Because, as we all know, if “a doctor on TV” says something, then it MUST be true (even though sixty percent of doctors in the US don’t have a single nutrition course built into their medical school curriculum, and thirty-five percent can take one course as an elective).