Does Diet Soda Make You Fat?

If you're reading this post because of its eminently Google-able title, you've come to the right place.

I'd like to welcome you with this suggestion: we should have an agency whose mission it is to help ensure the safety of our food and drugs. I know there's something called the "Food and Drug Agency," but it's clear that their charter is strictly one of reassurance, and they exist mainly to calm jittery markets, like the Federal Reserve Bank does in the realm of finance.

For example, in the aftermath of the deaths of scores of pets from melamine-tainted food, when it was revealed that pigs raised for human consumption had also consumed the poison, the FDA stepped in to tell us "hog meat (is) safe to eat, testing shows." Take note of how relieved you feel after reading this excerpt:

Testing confirms that meat from these hogs is safe for human consumption... that there is very low risk of human illness from eating such meat.

From time to time it may prove unfeasible to paint a smiley face on some problem that crops up, like contaminated spinach or canned chili that could cause botulism. Fortunately, the news cycle is refreshed so frequently these days, these things tend to blow over quickly and the only people who remember are the relatively few families of those who were killed.

Though a morass of regulations exists to control the sale of dietary supplements, certain non-specific quasi-medical statements are permitted. The result? Indistinct claims of vaguely healthful-sounding properties that confer supernatural powers to dietary supplements and give those who are ill and those who are merely hypochondriacs equal-opportunity expectations for amelioration of their afflictions.

Often encountered in the wild is a species of vapid gibberish that tries to evoke a complete theoretical framework to account for its existence. I found this in a brochure I picked-up from my local health food store:

FOOD IS THE KEY TO NUTRIENT UTILIZATION

Nutrients in their FoodState have the inherent benefits of Vital Food Factors not found in ordinary vitamins and minerals.

FoodState nutrients have potencies as found in FOOD which facilitates absorption and reduces potential for side-effects.

Doesn't it make you wonder 'why not just eat food?'

Acting as enablers in this tableau are news outlets that obfuscate as efficiently as they illuminate.

Results from studies of widely-varying significance take on similar weight when they are reported without sufficient context and critique. How is anyone supposed to reconcile a study purporting to show the anti-cancer properties of beta-carotene with another showing its pro-cancer properties?

Bottom line: Some good research—mostly involving beta carotene from the diet—suggests that beta carotene could lower the risk of cancer and possibly other diseases...Then came two first-rate studies showing that beta carotene supplements could cause serious harm, at least in smokers.

It's in this spirit of "everything is true and its opposite" that I return to the question "does diet soda make you fat?" There are a couple of studies that would tend to support an answer in the affirmative. One, from Sharon P. Fowler, MPH, and colleagues at the University of Texas Health Science Center, San Antonio used data that was collected for 8 years.

Now, here is the interesting thing about science: sometimes something that seems completely obvious can be shown to be incorrect.

In keeping with the open-minded approach of a dedicated researcher, this is Ms. Fowler's reaction to her own findings, as reported at an annual meeting of the American Diabetes Association in San Diego:

What didn't surprise us was that total soft drink use was linked to overweight and obesity. What was surprising was when we looked at people only drinking diet soft drinks, their risk of obesity was even higher.

Contrast that with analysis given by well-known diet guru Dr. Dean Ornish:

"There is no plausible physiological mechanism to explain this, and that causes me to question the accuracy of the methodologies used in this study."

Does he undercut this position with his role as a consultant to PepsiCo and chairman of its Health and Wellness Advisory Board? No more so than he undercuts his advocacy of a low-fat diet for heart health with his appearance on the McDonald's web site.

Frankly, Dr. Ornish, it makes you look like a corporate shill, endowed with the power to turn fish oil into snake oil. No offense intended.

So there it is, a complete interlocking system of news outlets, celebrity diet doctors, unscrupulous supplement manufacturers and willfully uninformed consumers. Maybe we deserve the FDA we've got.

For more information on the questionable validity of vitamin consumption, have a look at this BBC trailer: