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Hooked on diet soda

An addict tries to cut back because of its health hazards

Wendy Wahman for the Boston Globe

I am an addict. I’ve never been to rehab. I’ve never brought it up with my doctor. But I definitely fit the definition of someone who devotes or surrenders himself to something habitually or obsessively. What’s my poison, you ask? Diet soda.

While I'm not really sure when I picked up this habit, I've recently become aware of the incredible amount that I drink. For a while, I tried sticking to just one can a day. Yet, gradually, I slipped back into my old routine. First, a free refill at lunch. Then, a couple cans after dinner. A few weeks later, I found myself walking down Madison Avenue in New York City with a Super Big Gulp, wearing my medical school T-shirt and getting stares from tourists. Apologies, Mayor Bloomberg. And Harvard.

As of this writing, I'm back to around three or four cans per day. Some days, it's Diet Coke. Other days, it's Diet Dr. Pepper. When I'm in a bad mood and haven't had any soda for a while, my friends joke that I need my aspartame fix. However, I know that it's the caffeine withdrawal that causes the headaches. I might get scared by the fact that I can go days without drinking an actual glass of water. Nonetheless, the rest of the country seems to be on the same page.

Half of Americans drink diet soda on a regular basis, and we drink 20 percent more of it than we did 15 years ago. Even as sales of sugared soda have plummeted amid widespread criticism and the obesity crisis, diet soda consumption has performed much better in recent years. The US industry has grown to $10 billion in annual revenues, and we consume roughly 4 billion gallons of the stuff each year. In 2011, Diet Coke made headlines after passing Pepsi to become the second most popular domestic soda (behind regular Coke).


A paradigm shift in our soda drinking seems to be taking place, but it may not be for the better, as a growing body of evidence suggests that these artificially sweetened beverages may be just as harmful as their caloric counterparts. Diet sodas have been linked to a variety of medical problems, ranging from weak bones to kidney dysfunction, acid reflux to reproductive disorders. The acids in these drinks erode our teeth, and researchers have compared this effect to the use of methamphetamines or crack cocaine. In one study, people who drank diet soda on a daily basis had a 48 percent higher risk of heart attack or stroke compared to those who did not consume these drinks. In another, the guzzlers had a 67 percent higher risk of developing diabetes. Perhaps most troubling of all, several studies have indicated that diet sodas may not be "diet" at all and may actually cause weight gain among consumers.


While the hazards of sugary sodas have entailed significant policy implications, the adverse effects of diet sodas have yet to have a similar impact. The Department of Agriculture just released "Smart Snacks in School" — federal nutrition standards that effectively ban sugared sodas, but keep diet sodas, in high schools around the country. Efforts to legislate soda taxes from Washington, D.C., to California exempt diet soft drinks from regulation. Even Mayor Michael Bloomberg's sweeping prohibition on oversized sodas in New York City left diet beverages out of its reach.

The emerging dangers of diet soda, combined with our continued and widespread consumption of these drinks, reminds me of the TV show "Mad Men" and my incredulity at American behaviors from days past. Watching scenes of women smoking over their babies or men puffing away in crowded elevators, I've asked my grandmother, a former smoker, "How did you not know that inhaling burning smoke every day was bad for you?" She always replies, "We just didn't think about it."


Sugary soda has often been referred to as the new tobacco. But might diet soda join the ranks of consumer products with more health risks than originally recognized? With each study that comes out, we can see the subtle, pervasive effects of these drinks a bit more clearly. Legislators and parents alike should take these concerns into consideration. In 50 years, I fear that my grandchild will ask, "How did you not know that drinking black acid every day was bad for you?" To which I will reply, "We just didn't think about it."

Nathaniel P. Morris attends Harvard Medical School.