Reader Question – What’s the Deal with Lark Health?

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I have had several readers ask about the Lark program. In each case, it was being actively marketed to them, without their consent, by their insurance company and/or employer.

Lark is, predominantly, a weight loss program that also bills itself as a “diabetes prevention” program and “mind body” health coaching all offered by an Artificial Intelligence powered app. (Note that while it has various health programs, the big font headline at the top of the website says “Lose weight and be your healthiest self with Lark.”) It is covered by some insurance, and people can “earn”  things like a scale and a fitbit by meeting “minimum program engagement requirements, such as weighing in, completing missions with your digital coach, and logging activity or meals.”

The graphic on their website that they are calling “clinically proven results” says:

5.3% average weight loss in year one (1)

40% achieving greater than or equal to 5% weight loss in year one (1)

9.6lbs average weight loss by Lark members beyond 2 months in the program (2)

(1) Based on Lark program data for members meeting CDC qualification criteria
(2) For those with available weight data

These results are from the study Weight Loss in a Digital App-Based Diabetes Prevention Program Powered by Artificial Intelligence,  Graham SA, Pitter V, Hori JH, Stein N, Branch OH. Accepted, Digital Health, vol 8. 2022. DOI:10.1177/20552076221130619 (as always, I don’t link to studies that pathologize higher-weight bodies, but I provide enough information for those who are interested to find them on Google.)

The study’s lead author is Sara Graham who, according to LinkedIn is the “Clinical Research Manager at Lark Health”, in fact, per the conflict of interest statement, every single study author is employed by Lark.

Let’s dig in, shall we?

Let’s start with the study’s stated conclusion:

[Lark] facilitated weight loss and maintenance commensurate with outcomes of other digital and in-person programs not powered by AI. Beyond CDC lesson completion, engaging with AI coaching and frequent weighing increased the likelihood of achieving ≥5% weight loss. An AI-powered program is an effective method to deliver the DPP in a scalable, resource-efficient manner to keep pace with the prediabetes epidemic.

When they say “commensurate with outcomes of other digital and in-person programs” what I think you’ll find they mean is – people didn’t lose much weight, just like with every other program as we have seen in research for the last hundred years.

And when they say it’s an effective way to deliver the DPP [Diabetes Prevention Program] it’s important to know that they did not, in any way, measure blood sugar, or anything other than weight and weight loss.

But let’s really dig into the numbers:

The one-year study started with 3,933 Lark Members, but at its 12 month conclusion only 414 members had provided beginning and ending weights.

Those 414 were divided into two groups for comparison:

Group 1: CDC qualifiers: Completed ≥4 educational lessons over 9 months (n = 191)

Group 2: CDC non-qualifiers: did not complete the required CDC lessons but provided weigh-ins at 12 months (n = 223)

So, did you catch that? They started with 3,933 members and only 191 actually managed to stay with the program for a year. (The other 223 “group 2” didn’t complete the program but did provide their weight at the beginning and at 12 months.)  

My first question is: Do the results matter if fewer than 5% of people even make it to a year on this program? I think the answer is…not really, but let’s go ahead with the analysis.

What they actually found is that the 191 people in group 1 lost, on average 5.3% of their body weight, while the 223 in group 2 lost, on average, 3.3% of their body weight. So those who completed the program lost, on average, 2% more weight over the course of a year.

To put some numbers on this, a 200-pound person who completed the coaching would expect to lose, on average 10.6 pounds in a year, while a 200-pound person who didn’t complete the coaching would lose 6.6 pounds. So this shows that a 200-pound person who completes the 12 month program can expect to lose 4 pounds more than someone who didn’t complete the program.

Four pounds. In a year.

Think of what the phrase “clinically proven results” would lead you to believe about a weight loss program. Then consider that they are using the phrase “clinically proven results” to characterize 4.8% of study participants losing, on average, 2% more weight than 5.6% who did not complete the program but at least provided a 12-month weigh-in, a conclusion which doesn’t include any data for 89.6% of the study participants.

If you’re currently asking yourself something like: “Wait, doesn’t this kind of prove that their program is useless? And why, like, in the world, would anybody brag about these results?” then welcome to the world of weight science, friend. Where the diet industry props itself up with research that would fail any freshman-level research methods class, concluding that any amount of weight loss, no matter how tiny and in how few participants, proves “success,” and utilizing myths (of which they are the architects,) like claiming that 5% weight loss leads to “clinically meaningful health changes.”.

And, again, they only tracked participants for one year. Given that a century of research shows that, by far, the most common outcome of weight loss attempts is weight loss in year one followed by weight gain in years two through five, studies that don’t have at least five years of follow-up are, as far as I’m concerned, worse than useless since they irresponsibly try to induce people into what the research tells us is most likely an experience of weight cycling, which is independently linked to harm.

Here is where things get particularly ugly. Lark’s website bears the CDC logo and the phrase “Lark is fully recognized by the CDC to help lower risk for type 2 diabetes.” That’s because the CDC gave them “full recognition status” which, per the CDC, means that an organization “must show that it can meet CDC standards and effectively deliver a proven diabetes prevention lifestyle change program” Again, their study ONLY looked at weight, not any actual blood sugar measurement, and found that less than 5% of the study participants actually completed the CDC requirement for a year and those people only lost a tiny amount of weight.

This means that not only is Lark selling weight loss and diabetes prevention magic beans, but the CDC is backing them, which is how they are insinuating themselves into insurance companies and employers who then market this for-profit company to unsuspecting people, many of whom will incorrectly assume that their insurance company, the CDC, and a program that brags about “clinically proven results” can be trusted when it comes to weight and health.  

So that’s Lark. The slang definition of which is “harmless fun or mischief.” Unfortunately, this is anything but harmless. It is, quite simply, unconscionable.

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*Note on language: I use “fat” as a neutral descriptor as used by the fat activist community, I use “ob*se” and “overw*ight” to acknowledge that these are terms that were created to medicalize and pathologize fat bodies, with roots in racism and specifically anti-Blackness. Please read Sabrina Strings: Fearing the Black Body – the Racial Origins of Fat Phobia and Da’Shaun Harrisons Belly of the Beast: The Politics of Anti-Fatness as Anti-Blackness for more on this.