'Carb Sensitivity Program': The dumbest diet book?

A naturopathic doctor's latest tome relies on too much pseudoscience to be anything other than a fad diet book


It landed on the desk at Science-ish headquarters with a thud: the 482-page Carb Sensitivity Program by Natasha Turner, a naturopathic doctor who penned the bestseller, The Hormone Diet. The skeptic in Science-ish was aroused. And after an inner battle about whether the book deserved any ink—even of the digital sort—its promises to help readers “discover which carbs will curb your cravings, control your appetite and banish belly fat” called out for a debunking.

Now, this isn’t about picking on easy, pseudoscientific targets. The reason for the urgency is this: we too often hail new miracle diets without questioning the shaky (at best) evidence supporting them. Just look at the list of reputable news outlets that have already covered Turner’s work. If carbs truly were the enemy, Yoni Freedhoff, an evidence-based obesity-focused doc, rightly pointed out, “When one in seven Americans was on the Atkins diet in the early 2000s, we would have seen the obesity epidemic go away.”

But let’s examine some of the claims Turner makes in the book. First, she begins with irresistible questions readers will no doubt identify with: Do you have a sweet tooth? Do you get sleepy or mental fogginess after meals? Do you feel bloated, especially after meals? Do you have a very large appetite or an obsession with food? According to Turner, this means you’re probably “carb sensitive.” According to Science-ish, this means you are probably human.

Still, Turner has the answer. A “carb rehab program” that will “repair your metabolism” so you become “symptom free” and “lose belly fat.” For beginners, there is no evidence whatsoever to support the notion that targeted fat loss is possible. (Check out Tim Caulfield’s book The Cure for Everything!) So any time you see a magazine or book promising to help you “bust the belly fat,” chuck it. It’s a bold-faced lie.

Turner also suggests a “supplement regime to aid detoxification.” The detox concept should sound alarm bells in any thinking person’s mind. There is reams of evidence-based literature on why the notion of a detox is bunk. But this group of scientists did a good job of summing it up: “‘Detox’ has no meaning outside of the clinical treatment for drug addiction or poisoning.” People are not full of toxins that can be expunged from their systems by systematically eliminating one food group—though it’s an appealing concept. The body can deal with the everyday chemicals it encounters and it certainly doesn’t need the Clear Detox hormonal health pack—supplements from Turner’s own wellness boutique—that she prescribes in the book.

Unscrupulous peddling aside, people who follow the diet in the book may indeed lose weight. But, “carb-sensitive” or not, anyone who consumed what Turner is suggesting for a typical day—one fruit smoothie in the morning, a “carb sensitivity shake” as a snack, “immunity-boosting Ginger Chicken” for lunch, and cauliflower and kale soup with turkey breast for dinner—would shed a few pounds.

Like the followers of many fad diets, Turner’s readers may attribute weight loss to her design. Just keep in mind what Caulfield told Science-ish: “These fad diets cause you to pay attention to what you’re eating for a specific amount of time, which forces you to concentrate on your food, and the result is weight loss. You attribute this weight loss to a magical return on your investment in the book. It’s not. (You lost weight) because you paid attention to what you’re eating.”

Now, Science-ish has shown before that comparative studies have found that just about every diet works to the same degree when it comes to losing weight. (See this trial and this one for more good evidence of that.) If it were as simple as following a fad diet, like the one Turner is selling, we’d all be thin. But, as this recent survey found, women have tried over 60 diets by the age of 45 in an effort to keep trim. We’re still overweight.

This should not be depressing news, however. It’s freeing. We can stop putting money on diet books and lining the pockets of deceitful peddlers of pseudoscience, and get on with life.

Science-ish is a joint project of Maclean’s, The Medical Post, and the McMaster Health Forum. Julia Belluz is the associate editor at The Medical Post. Got a tip? Seen something that’s Science-ish? Message her at julia.belluz@medicalpost.rogers.com or on Twitter @juliaoftoronto

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