Diet Frostie

Really? Germs Love Diet Soda?

We’ll say it again. You don’t need a scientific reason to hate artificial sweeteners. It’s OK. But even so, people keep coming up with speculation, dressing it up with science, and making unfounded claims about the bad effects of sweeteners. Today, Moises Velasquez-Manoff is telling us in the New York Times that germs love diet soda.

And thus he says, diet soda may be ruining our microbiome and our health. He applies the same logic to all processed foods.


For evidence, he cites three studies. The first is a study in mice that shows a food additive called trehalose can make Clostridium difficile more virulent for those mice. C-dif can infect and disrupt the normal microbiome of the gut. The study offers a basis for speculation, not evidence of harm to humans. And incidentally, trehalose is not an ingredient in any diet soda.

The second one was a lab study that suggested a strain of E. coli associated with Crohn’s might be enhanced when fed maltodextrin. It’s a common food additive, and you might find it in beer. But you won’t find it in diet soda. And again, no evidence of harm to humans.

The third study is one we’ve written about before. Researchers fed high dose saccharin to mice and found changes in their microbiomes and their glucose tolerance. They also did an uncontrolled study of seven human volunteers. They proved that putting high-dose saccharin in a mouse’s water supply is not nice. And by the way, you won’t find saccharin in diet soda these days.

Sciency Speculation

Keeping perspective on the difference between speculation and evidence is always a good idea. Careful reviews of all the available evidence in humans tell us that low calorie sweeteners are safe. Many people want to drink a sweet beverage, but limit their intake of sugar. They don’t need fear mongers telling them to stick with real sugar.

If you don’t like low-calorie sweeteners, that’s OK. But making up a sciency-sounding rationale is not. It’s just a clever form of propaganda. And no, germs don’t “love” diet soda. They like cheese better.

Click here for the article by Velasquez-Manoff.

Diet Frostie, photograph © Roadsidepictures / flickr

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April 7, 2018

4 Responses to “Really? Germs Love Diet Soda?”

  1. April 07, 2018 at 7:24 am, Joe Gitchell said:

    Thank you, Ted, for laying this out so clearly and simply.

    The only downside is that my ears are ringing with a cacophony of echoing nicotine/vaping demonization bells!

    Lots of Ding-Dongs, I assure you.

    Getting philosophical for a moment: I sure hope that you and I don’t shuffle off this mortal coil BEFORE such harmful distortions become the subject of history, not current events.

    In health,

    • April 07, 2018 at 8:56 am, Ted said:

      Amen. Fear mongering is a threat to public health, not to mention sanity. Thanks, Joe!

  2. April 07, 2018 at 10:25 am, Charles Baker said:

    Thank you Ted. This matter is extremely important.

    Speculation like this is even more insidious than “dressing it up with science.” When biases continue to be masqueraded as scientific evidence, it’s little wonder that public health struggles to advance.


  3. April 08, 2018 at 2:22 pm, Susan Burke March said:

    Thanks for this column, Ted. I wrote a letter to the editor of the NYTimes, and invited them to read your column. “Science writer” indeed.