Addictive Seltzer: Examining a Bold Claim

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The chemicals in LaCroix

Here are a few wacky things I believe: that anyone who puts raisins in stuffing is a monster; that the combination of social media and artificial intelligence is a potentially existential threat to humanity; that geese are the biggest jerks of all animals. Here’s a wacky thing I don’t believe: that seltzer is addictive.

This disbelief puts me at odds with a Cornell and Rutgers trained doctor, which is an interesting place to find myself, so much so that I want to explain how I got here. Whether your immediate reaction to the claim is, “duh, of course seltzer isn’t addictive” or, “the industrial food system is so corrupt I’m inclined believe literally everything negative about it” or anything in between, I hope you’ll come on a journey of discovery with me. We’re going to swim through a fizzy, lightly flavored lake of LaCroix, passing Basil Atoll, Roach Killer Reef, cruise ships of studies, and life rafts of common sense, to hopefully arrive at the Island of Enlightened Clarity.

And if that doesn’t entice you, I promise to come up with several even worse metaphors before I get through with it.

Background

In 2018 there was a lawsuit alleging that LaCroix sparkling water used synthetic chemicals. It was thrown out in 2020, because the plaintiff never provided solid evidence of the central claim. That is, they couldn’t prove that the flavors in LaCroix were synthetically derived rather than natural.

This is an important point. Linalool, a compound that will be the focus of this post for reasons that will become clear, naturally occurs in quite a number of plants, ranging from basil to lavender to blueberries to marijuana. It is possible to isolate it from a plant source, yielding pure linalool that is naturally derived, and thus considered natural, in contrast to linalool synthesized in a laboratory, though it is impossible, or nearly so, to distinguish the two. It appears to be true that some flavors of LaCroix seltzer — excuse me, LaCroix Sparkling Water — do contain linalool, though I have no reason to believe that it isn’t naturally derived.

The New Claim

But now a new series of claims are being made in a post on seltzer by Dr. Cate Shanahan. Specifically, Dr. Shanahan argues that, whether natural or synthetic, isolated compounds generally and linalool in particular are dangerous and should be regulated. She writes, “Natural or not, I think we should be told these chemicals are in there. I mean if they’re so safe and healthy, then why does the company need to keep them secret?”

I instinctively agree with this impulse. I dislike opacity in the food system, and so I tend to support anything that works for transparency, even if I don’t think labels can do very much to provide clarity.

That said, I can think of two obvious reasons food companies would not want to list every specific compound in their flavoring blends other than hiding their harmfulness. First, I suppose it might help competitors figure out how to mimic a particularly tasty product. More realistically, it’s because many people will assume that “natural flavors” are healthier than something like “linalool” or even “linalool derived from oranges” regardless of whether they actually are healthier. I include myself here! I generally trust a product with a shorter ingredient list more than a longer.

But Dr. Shanahan goes much further, and here’s where it’s important to take a hard look at how we arrive at conclusions. She advances two arguments more or less in tandem, but I’m going to take them one at a time, like a batter watching two fastballs in a row go straight down the middle of the plate. Actually, that would be a bad thing to do. I’ll be like two batters hitting home runs on consecutive at-bats, but both batters will actually be me, even though that could never happen in a real baseball game, and even though I never played baseball.

First argument: linalool is a roach killer, therefore, LaCroix contains roach killer

I’ve got to admit, this sounds pretty bad. I certainly don’t relish the idea of sipping on a nice, refreshing can of roach killer on a hot summer day, even if it has a delicious cherry-lime flavor, is ice cold, and just really hits the spot. And it is true that a number of pesticides do contain linalool. But as I mentioned, so do a ton of common foods. I could just as well say, “blueberries found to contain roach killer!” or, “basil found to contain roach killer!” or, “lavender found to contain high concentrations of roach killer!” since linalool is one of the primary constituents of lavender oil.

I’ll also note that the choice to use “roach killer” rather than a broader term like “insecticides” is clearly to provoke a visceral reaction by associating LaCroix with a bug that connotes filth and contamination; I don’t want to drink any insecticide, but I really don’t want to drink roach killer.

Dr. Shanahan gets around the annoying fact that linalool pops up all over the place, often to remarkably delicious effect, by focusing on concentration. “Linalool may exist in nice-sounding things like basil and lavender, but in relatively low concentrations.” First, I take issue with the idea that basil is just ‘nice-sounding.’ Basil is delicious. If I had my way we’d all be swimming in pesto.

The larger point is also important. If LaCroix contains far more linalool than the amount that naturally occurs in commonly eaten plants, it would be a reason to entertain the idea that drinking it might be substantially different from eating a handful of blueberries. The amount of a substance really matters!

A great way to illustrate the old adage that the dose makes the poison is to consider alcohol. Enough alcohol at once will kill you, as will chronic overuse of alcohol. Most people can tolerate a drink or two without adverse effects, but many people choose to abstain entirely. Yet even teetotalers consume some alcohol. It’s present in small amounts in very ripe bananas. It shows up in bread and kombucha. Vanilla extract often uses alcohol as a carrier and preservative. But these sources contain such miniscule quantities that it is truly negligible. It has no detectable effect on health.

This brings me to the most frustrating part of both this post I’m writing and Dr. Shanahan’s. Neither of us have a clue how much linalool a can of LaCroix contains. I’ve looked high and low for this information, for even a broad estimate or industry standard on natural flavor use. I gave up when I found myself scanning the text of the lawsuit that started this whole mess in the hopes that it would be included somewhere. I wish I could put a number on it, because to seriously entertain some of the arguments I’m about to get to we would want to first be sure that LaCroix contains more linalool than common food sources.

That said, I think there is a common sense reason to suspect LaCroix does not in fact contain excessive amounts. As Dr. Shanahan points out, linalool is extremely potent, detectable in parts per billion to the human nose. Since it’s added to give seltzer a delicious, citrusy flavor, I am inclined to believe the food scientist quoted in this article, who argues that companies generally use chemicals in quantities comparable to those that occur naturally in foods, for the obvious reason that adding more would taste really bad.

At least, I think linalool is added to seltzer because it has a pleasant taste. Dr. Shanahan has a different theory, which brings us two her second argument.

Second argument: linalool is a powerful, potentially addictive drug

While I have some sympathies for the first argument — if companies are sneaking in significant amounts of virtually any chemical they choose under the umbrella of “natural flavor” I’d want to know — I cannot say the same for the second. I struggle to figure out how to engage with it, because it is at once sweeping and amorphous. Perhaps a good place to start is with Dr. Shanahan’s conclusion.

She writes that linalool has similar effects on the brain as recreational drugs like Ritalin, Ketamine, and phencyclidine, AKA angel dust. “Depending on how your brain responds to it, LaCroix water may help you break the ice at parties, relax during exams, or concentrate better during your studies. Just like methamphetamines. It’s got so many uses!”

One line of evidence Dr. Shanahan marshals to support this is the fact that linalool has been studied as a potential treatment for conditions like anxiety, bipolar disorder, and depression. True! But from my reading of the studies she links to, a few things stand out. First, none of them, so far as I can tell, report any stimulant or dissociative effect. I’m a bit out of my depth when it comes to assessing medical studies, but I hope that if linalool was basically “a legal, cheap, liquid form of Ritalin” someone would have flagged it.

Here again the topic of dose size comes up. Dr. Shanahan says, “Notably, the doses found to have psychological effects are really small, about 2-3 milligrams for an adult human.” This isn’t clearly cited, but assuming it’s referencing the previous link in her article, which is an analysis of a broad range of studies of linalool, I cannot find the source. Of the summarized studies that have human subjects I do see one that lists a dose of 2.8 milligrams, but it appears to me to be a measure of aerosolized linalool. Again, I’m not sure about this, so please let me know if you can shed any light on it!

But I also notice a human study that uses an 80 milligram daily dose of a drug called Silexan. Legal in Germany for the treatment of anxiety disorders, Silexan is a lavender extract that is 36% linalool, meaning each dose contains about 29 milligrams. If linalool is basically meth, is it really plausible that a significant number of people are taking this much every day for anxiety without noticing that it makes them a touch jittery?

The next line of evidence is the idea that marijuana contains linalool. “To get a really good wallop of linalool you have to reach for a roach of a different kind; weed or CBD oil. Most naturally derived linalool today seems to be derived from the marijuana plant. For that reason alone, it should raise alarms that it may have drug-like effects.”

No, it shouldn’t. As previously noted, linalool occurs in hundreds of plants, most of which have no mind-altering qualities. Again, lavender contains tons of it. The fact that it also occurs in marijuana tells us nothing. This is similar to the repeated use of roach killer in that it is about creating an association rather than presenting an actual argument. The logic goes like this: marijuana is mind-altering, marijuana contains linalool, therefore linalool is mind-altering. But I could also say: blueberries are not mind-altering, blueberries contain linalool, therefore linalool is not mind altering.

Dr. Shanahan also makes a big deal about the neurochemical pathways linalool may effect. Here’s a graphic she includes.

It’s interesting that drugs can change how spiders weave webs, but if you look at the list of studied compounds you’ll notice that linalool is not one of them. Benzedrine is, and Dr. Shanahan says that because linalool operates on a similar pathway, it is substantially the same, just as it’s substantially the same as Ritalin, Ketamine, and meth. (Also of note is that caffeine appears to have a larger impact that Benzedrine or pot, and I resist any information that suggests I should cut back on coffee.)

This is getting into drug mechanisms and neurochemistry, an area that I don’t have even a superficial understanding of, but I’m skeptical that it’s a reasonable way to draw any firm conclusions, particularly when the listed drugs are so very different.

But the most specious argument has to do with the potential addictiveness of LaCroix. Linalool is included as Flavoring with Modifying Property or FMP. Dr. Shanahan writes:

What does an FMP modify?

I think it’s us.

I read through this FMP protocol process and I think they’re not so much interested in secretly adding sugar or salt. They’re looking for ingredients they can use for impact boosting on more expensive ingredients, like Stevia, which is costly. I bet you a dollar they’re also looking for addictiveness. After all, if you’ve got something to sell, it’s always a bonus if you can get people hooked.

For this to be true the evil scientists at LaCroix would have to first conduct secret experiments to determine that linalool is in fact addictive (a property reported in none of the studies Dr. Shanahan cites) then intentionally add it to their products in an effort to boost sales. But the scientists couldn’t be operating on their own — why would they do this unless they had a directive from higher up?

In other words, it would have to be a well-funded conspiracy within LaCroix to systematically research naturally derived chemicals for mood altering effects, then to preferentially add those with the most potential addictiveness in order to make an unsuspecting public dependent on fizzy water. I suppose it’s possible, but I’d like a bit more evidence before I’m ready to entertain the claim that Big Seltzer is out to literally make us all users.

That said, if a LaCroix whistleblower has the goods on this scheme, please get in touch!

How we know what we know

Here’s a quick recap of the claims:

1.) LaCroix contains roach killer.

2.) Linalool is powerfully psychoactive.

3.) Linalool is addictive.

Please read Dr. Shanahan’s post, read mine, and come to your own conclusion about which way the evidence points, then meet me back here.

Now, join me in cracking open a nice refreshing can of LaCroix. Maybe we’ll drink cranberry flavor, since it’s almost Thanksgiving. I encourage you to make your own notes, but here’s what I’m noticing. It tastes pretty good, but my tongue is tingling a little bit, almost like it’s numb. I was thirsty, but it leaves my mouth with a dry sensation, which makes me want to have another sip, like it can’t quite quench my thirst. At the same time, I’m feeling energetic. It’s subtle, but it’s there.

Maybe you had a different reaction. Maybe you felt tired and took a nap. Maybe you felt relaxed or talkative. Maybe you didn’t feel any different, which has always been my experience of drinking flavored seltzer prior to encountering this article.

The purpose of this exercise is to highlight something about Dr. Shanahan’s framing of her post. After a brief summary, this is how she opens it:

I’d been getting headaches after drinking my afternoon pick me up — a refreshing cocktail made with LaCroix flavored sparkling water and black tea. I thought it was from caffeine, so cut out the tea the next day. Then I noticed something weird: I still felt funny drinking just the flavored water. Hard to describe; like jittery but still calm, and I noticed myself talking ridiculously fast, as if I’d just OD’d on caffeine.

Set that next to the claim in the penultimate paragraph, which I previously quoted but will repeat here: “Depending on how your brain responds to it, LaCroix water may help you break the ice at parties, relax during exams, or concentrate better during your studies. Just like methamphetamines. It’s got so many uses!”

This invites you to judge the truth of the article personally. When I drank that cranberry LaCroix a moment ago I was much more attuned than usual to my physical response. But because the potential affects Dr. Shanahan ascribes to linalool are so broad and nebulous — jittery but still calm, the life of the party, relaxed, focused, literally on meth — I was invited to interpret anything I felt, even subtly, as being caused by LaCroix, rather than by skipping breakfast, going on a brisker than usual walk, or most likely the simple expectation that I would feel different.

If you drink a LaCroix and then notice a strange feeling within yourself, you are much more likely to give credence to Dr. Shanahan’s thin but superficially scientific explanations for why it might be so. Her article primes you to closely analyze the experience of drinking seltzer, then uses that priming as the foundation to encourage you to believe the less than bulletproof evidence that follows.

My hope is that by presenting the evidence first and the anecdote second I’ve reversed this dynamic.

Embracing discomfort

Rising above LaCroix Lake we can see Mount Uncertainty, which sits at the center of the Island of Enlightened Clarity. It has been an arduous journey, and I appreciate your stalwart companionship for the many words it has taken to get here. But now we have one more difficult task before us. That’s right, to reach our goal we must find our way into the Current of Necessarily Choosing a Course of Action While Acknowledging That There’s a Whole Lot of Stuff We Simply Don’t Know.

Here’s the problem: the food environment is a complex system, created by an interplay of farming, food processing, advertising, culture, and probably a bunch of other factors. So significantly improving health outcomes for the population that lives in this food environment, reducing the incidence of type 2 diabetes, for example, would most likely require systemic change, which is incredibly difficult.

But this is an incredibly disheartening message, and so we engage in a strange doublethink. The diagnosis is systemic, but the prescription is individual; because there is no realistic prospect for improving the food environment as a whole, at least in the near term, we must figure out for ourselves how to best exist within it. We try to find the right diet or exercise regime, we count calories or go vegan or go carnivore, we do Crossfit or run twenty miles a week.

I endorse this sort of experiment! What else can we do but try to find a way to live relatively healthy lives in a system that is working against us?

But this state of affairs can make it a great comfort to discover a well credentialed expert — a doctor who’s gone to excellent schools, has worked with the LA Lakers, has been featured all over the mainstream press, has glowing testimonials from both famous and everyday people — who can explain in detail, while authoritatively engaging the science, which foods are bad and which are good.

The danger I see here is not in the diet itself. I broadly agree with Dr. Shanahan’s focus on making whole, unprocessed foods the center of every plate, and if avoiding LaCroix isn’t necessary, doing so won’t hurt you.

The danger is false certainty. When it comes to food and the food system broadly, as well as whether there’s a rapidly approaching AI apocalypse, I want to see clearly. The first step of doing so is recognizing how much I don’t know, or only suspect, or have decent but not ironclad evidence for. When I read a study I want it to disconfirm my presuppositions as often as it confirms them. When I feel funny after a sip of seltzer I don’t want to mistake it for evidence of a conspiracy. I want to be able to change my mind.

Except about the raisins. Anyone who adds them to stuffing should be launched into the sun.