In January of this year, I decided I would complete a half-marathon. I would push my body to the limit and be reborn as my best self. For months, I woke up at 6 to run before work, motivated by the promise of sweet endorphins and even-sweeter self-righteousness. But then the winter wore on, and I gained some weight, and now I’m back to 5Ks instead.

In my quest to return to former glory, I redownloaded the “couch to half-marathon” app and spent $100 on a pair of New Balance shoes. I became interested in a genetic-testing kit that promised to provide the information I needed to complete 13.1 miles once and for all.

Genetic testing for wellness seems like a natural choice for someone like me. I still wear my Fitbit every day two years after getting it, making me one of the few and the proud that have stuck with their device for longer than six months. I own a smart scale and a running watch; I track calories and read training forums. But the forum advice is general, while the DNA test kit promised insights based on who I, specifically, am. In a society obsessed with optimizing ourselves, it follows that figuring out the “nature” part of the “nature versus nurture” equation can give us that extra competitive edge.

The test in question is available through Helix, a new consumer genomics company. Helix uses a more sophisticated method of genome sequencing than most other commercial DNA tests, and brands itself as a “platform.” It works like this: you send Helix your genetic data and it sequences it. Then, you buy various data analyses from third-party companies that you authorize to access your genetic information. The offerings are varied. You can learn about your risk for various genetic diseases and your sleep type, see what you and your partner’s baby might look like, or be served wine recommendations “scientifically selected based on your DNA.”

I purchased Helix’s one-time DNA sequencing kit for $80, and for my required add-on, I chose the $220 Fitness Diet Pro by DNAFit. Fitness Diet Pro promises to tell me how best to train and eat — everything from if I am sensitive to carbs to whether I recover more slowly than average after exercise. (My employer covered the cost, otherwise I could not afford it.)

When the kit came, I spent five minutes in the office bathroom surreptitiously spitting into the tube, then sealed it and sent it off. The results that came back provided me with interesting trivia — but it didn’t tell me much I didn’t already know from the fact that I live in this body. I wanted information that would help me improve myself, but in the end, Helix is genetics for entertainment.

When the Human Genome Project was announced in 1989, it was supposed to cost $3 billion. It ended up costing a little less, and the price has been rapidly dropping ever since. Today, sequencing is about 400,000 times cheaper than it was even in 2001, thanks to various breakthroughs in technology, says Steven Salzberg, a professor of genomics at Johns Hopkins University in Baltimore. Not only is DNA sequencing becoming cheaper, it’s also becoming more comprehensive and accurate.

Imagine that your DNA is a book filled with millions of letters. Most DNA sequencing works by looking at a few specific letters. Maybe you know that there’s a certain letter on page 47, and if the letter is A, then you’re slightly more likely to have Alzheimer’s, and if the letter is C, you’re slightly less likely.

These “letters” are called single-nucleotide polymorphisms, or SNPs (pronounced “snips”). SNPs are scattered pieces all over the genome, so in the end “you’re only reading a very small number of the locations,” says Salzberg. It’s like skimming the key sections when you don’t have time to read the entire book.

“I think Helix could be morphed into a very important and strong company if it got rid of all that junk.”

Now imagine that instead of looking at scattered letters, you’re figuring out what complete sentences say. Instead of working with scattered parts, Helix sequences continuous DNA segments that encode for specific genes. “The accuracy is very high,” says Salzberg, who adds that this method, called exome sequencing, is especially useful for finding causes of rare genetic diseases. In one of his projects, scientists sequence the exome of someone with a genetic disease and their healthy parents, then compare the entire strand for differences.

Genetic results can tell you ancestry and paternity, and provide information about inherited genetic disease like Huntington’s. They can spell out risks for cancer and other illnesses. There’s a large body of literature on the ethics of these tests and what this knowledge might mean for our choices, but that isn’t relevant in my case. A few years ago, I took a 23andMe test that told me, among other things, that I am 99.5 percent Han Chinese, not a carrier of any genetic diseases, and am likely to have dark hair. (I do. See: 99.5 percent Han Chinese.) I already know I am a relatively healthy person.

This time around, I’m interested in being even better. Wellness tests like Fitness Diet Pro tell you which variation you have of a gene that has been linked to a certain feature, like fast-twitch or slow-twitch muscles. In theory, once you have this information, you know the right foods to eat and the right exercise to make it across the finish line.

But that’s only true if you trust the research, and some of it doesn’t hold up. Eric Topol, a geneticist at the Scripps Research Institute tweeted that Helix was “giving consumer genomics a bad name” because it relied on shaky science. The sequencing itself is accurate, he says, calling Helix’s sequencing “first-rate,” but the analysis often isn’t. Many of the studies that suggest a link between a gene and a trait are based on poor data and studies that don’t replicate, according to Topol.

Helix offerings like the genetic screening for disease are based on good science, he says, but other add-ons — including Fitness Diet Pro — are useless. (Consider that a biologist came up with a satirical version of Heix’s wine DNA test before realizing it actually existed.) “I looked at many of these and they had no science to support them,” says Topol. “The customer is at a loss because they usually don’t have the time or ability to interpret the scientific article, which often they can’t access anyway. So how are people going to get the truth?”

After more than six weeks, my Fitness Diet Pro results came back: an array of brightly colored genotype PDFs with charts and images of happy people far more fit than me.

The reports weren’t just easy to read, they were careful not to overpromise. That makes sense; the US Food and Drug Administration once ordered 23andMe to stop selling its kits because the company had been marketing itself as a provider of health information without getting proper approval.

The legal disclaimer comes off strong: DNAFit absolutely cannot be liable for anything bad that happens to you if you take the advice. Each portion of the online report has a section clearly laying out what the test can and cannot tell you, and it warns that my results should not “be used to tell us what kinds of sport we can or cannot be good at.”

The superiority of Helix’s exome sequencing was very clear in one area. One of the supposed divides in sports is between athletes who need short bursts of power — think sprinting or power lifting — and athletes like marathon runners and rock climbers who focus more on endurance. When I took the 23andMe test in 2014, I learned that I have the gene for fast-twitch muscles associated with sprinters, though I am far better at 10K distances than I am at sprints. Fitness Diet Pro added more context by showing that though I do have the fast-twitch muscle gene, I actually have more genes associated with endurance sports. The report claims that I am 67.2 percent an endurance athlete and 32.8 percent power — numbers that seem absurdly precise. (The percentages are calculated by a Fitness Diet Pro algorithm that has been fed various studies on the effects of each gene.)

Andrew Steele, a former Olympian and co-founder of DNAFit, walked me through my results. Today, Steele is the head of product for DNAFit, but was once a professional athlete who won a bronze medal in the 4x400m relay at the 2008 Beijing Olympics. He doesn’t have the ACTN3 gene variant associated with fast-twitch muscles, the variant that the majority of elite sprinters have, and which I have as well. “I had some success, but it was the failure side of my career that made me learn what worked and didn’t work, and led me to discover genetics,” Steele tells me. The training advice Steele gave me was solid; he clearly has an enormous amount of nutritional and fitness knowledge.

I have a higher-than-normal risk of soft tissue injury, but have never had any injuries other than occasional twinges of knee pain, and I probably don’t work out enough to put myself at serious risk. Steele asked me about pain, and sent over some helpful exercises for my knees, such as wall sits with a medicine ball. On the bragging rights side, I have a slightly faster-than-normal recovery rate. To take advantage of my “power” genes, Steele suggested adding various types of intervals that would help me get faster and trainer better.

“The last thing we would want you to do is give up the exercising that you’re feeling comfortable with because you think it’s wrong because of the genetic result.”

The diet section rated me as “normal” on everything from antioxidant need to Vitamin B need to omega-3 need, and I’m not especially sensitive to carbs or saturated fat. Both this and 23andMe said I’m lactose intolerant (like most people in the world, it hastens to add). And I lack the gene variant that makes my liver better at detoxing. To make up for that lack, Steele said to eat more cruciferous vegetables, like broccoli.

The quality of Helix’s exome sequencing is excellent. But the company’s business model leaves much to be desired. For one, you don’t get access to your own genetic data. You can’t use it to learn about yourself, and if you want to do a non-Helix test or even present it to your doctor, you’ll have to get sequenced all over again. (Helix has said that in the future you may be able to purchase your raw data for an additional fee.)

Helix collects the demographic information, genetic information, and site-browsing information. It only shares the relevant genetic information with the partner (in this case, DNAFit), but the partner may have its own, different privacy policy. It’s always worth looking into the privacy policies of these companies, says Kayte Spector-Bagdady, a bioethicist at the University of Michigan. You should also be aware of if the company may be selling your genetic data, like 23andMe and Ancestry have done.

For example, DNA Fit’s privacy policy says that it won’t sell information to third parties without consent. Vinome, the DNA wine-test company, says the same, but it also adds that you won’t have rights to any products the company could develop using your genetic material. Arivale, a Helix partner that offers DNA wellness coaching, states that it may share your health information with labs or outside contractors to provide evaluations, or with third-party business associates.

Helix may recruit users to participate in medical studies, which is a potential boon when it comes to helping research progress. Right now, the majority of genetic data in biobanks comes from European and Caucasian participants, says Spector-Bagdady, and having more diverse participants — if they can afford the tests — could be helpful for further studies. These are promises we’ve heard before with Apple’s ResearchKit. In their case, recruitment really was bolstered — one of their apps already enrolled more than 41,000 people — but ethical and privacy issues remain. And if Helix released our data, we could participate in any study we wanted, not just the one the company approves.

Helix currently has nearly 30 offerings and is working on partnerships that will launch in the future. Mayo Clinic, for instance, is working with Helix to create a genetics-education app, according to Matthew Ferber, who runs the clinic’s Center for Individualized Medicine. “There are a lot of great books that talk about genetics, but if you don’t have a way to make it real for the individual, it’s hard to get people to move through the dense material,” says Ferber. The Mayo app will take the individual’s DNA itself to teach them about concepts such as autosomal dominance and pharmacogenetics. It’s great cause, but because Helix is a walled garden, Mayo participants won’t be able to access the rest of their data.

Topol, the geneticist from Scripps, says that he’s a “really big fan” of consumer genomics, but it has to be done right. That means providing everyone with their data and only providing results that have been proven by science, like information about genetic risk or how different drugs interact with DNA. Consumer genomics should be rigorous, not peddle results with likely no basis in reality. “I think Helix could be morphed into a very important and strong company if it got rid of all that junk,” he says. “But there’s no sign of that.”

Just because Helix has sophisticated sequencing technology, and just because Steele, the DNAFit co-founder, knows what he’s doing, doesn’t mean this information will help me complete my half-marathon. In almost all cases, genetic information alone simply isn’t enough to make us change our behavior and improve our lives. Studies show that being told you’re at genetic risk for something usually isn’t enough to change your behavior, so the outlook is even worse if you’re just trying to drop a few pounds or complete a race.

For me, specifically, some results might not be applicable because I’m Asian and research studies are often overwhelmingly white. And many of the “insights” were things I already knew. Fitness Diet Pro results suggested that I’m more sensitive to coffee than others, but it’s been clear for years that a few sips will keep me up all night. Steele’s training advice to run intervals was solid, but a quick glance through the r/running subreddit shows plenty of people advising everyone to run intervals, regardless of their preferred distance, and do wall sits. We should all be eating more broccoli and fewer Reese’s cups, liver detox gene be damned.

Plus, many tests are quick to point out that these genes only explain a tiny percentage of the variation in performance. That’s nothing, unless you, like Steele, are at the Olympic level. “For the vast majority of us who are not elite, that distinction is probably irrelevant,” says Brian Zikmund-Fisher, a professor of health behavior at the University of Michigan, and factors like your practice schedule matter much more.

Helix could tell me what I could be doing to improve, but it couldn’t do a single thing to help the biggest roadblock to my dream of the half-marathon

Being told your genetic risk for certain diseases didn’t make you any less likely to quit smoking or move more or even slap on some more sunscreen, according to a paper published in the British Medical Journal last year. “People are very sensitive to information about immediate threat, so if you see a sign saying ‘shark-infested water,’ the chance are that you’ll get into the water are low,” says study author Theresa Marteau, director of the Behavior and Health Research Unit at Cambridge University. But genetic tests give you information that seems abstract and far away.

If important health information isn’t enough to scare us into changing, suggestions about eating more broccoli won’t do much. And I know myself: grimly chanting “my body was built for sprints” won’t take any of the agony out when I do them, and won’t provide any more pleasure than I usually get (none; there is no pleasure in sprints) when I finish.

So what does work? “If we knew the answer of what would reliably shock people to change their behavior, there would be a transformation in human society,” says Zikmund-Fischer. Cambridge’s Marteau agrees, though she says that much of the answer lies in policy change, like soda and cigarette taxes. Social factors — Do you enjoy the activity? Does it fit in with your lifestyle and schedule? — are far more important than genetic tests when it comes to changing behavior. It’s our environments — economic, digital, social, and cultural — that often have the biggest influence on our behavior and that push us to be unhealthy.

When I asked James Lu, Helix’s senior vice president of applied genomics, about this argument, he says that people should decide for themselves what is useful. “Given an environment where people are willing to really try new things, to self-optimize, I think people have a right to information that’s scientifically valid,” he says. “And our goal is to make sure they understand what they’re getting and making the right kinds of decisions.”

Genetic testing, unlike astrology or the dubious claims of Goop, has the trustworthy gloss of cold, hard, reliable science. And as sequencing becomes cheaper and cheaper, it’s easier than ever to take a peek into the original birth charts: our DNA. But science, even if technically accurate, can be fairly useless.

Helix takes a serious branch of science and lightens it up, implying that DNA testing isn’t just about diseases and complicated, technical lab work. It can be about turning your DNA into a scarf. And treating science like entertainment might have negative effects.

It’s not that science can’t be fun. 23andMe gave results on the type of earwax you have, and whether light makes you sneeze. But it also provided useful information on genetic risk. With Helix, you can receive dubious data with none of the useful insights, and popularizing dubious science is counterproductive. “I think it’s unusual for us to think of scientific work that doesn’t have legal and scientific standing, with the idea that we need to ‘take this science with a grain of salt,’” says Jonathan Marks, a professor of anthropology at the University of North Carolina, Charlotte and author of Is Science Racist? “This probably the the wrong direction for the scientific community to be leading the public in, if we’re apprehensive about people not taking science seriously enough.”

In the end, Helix is little more than a form of astrology. Sure, it seems ludicrous to think that my astrological sign will affect my life — but various studies have looked at the influence of peoples’ month of birth on education, childhood intelligence, and socioeconomic status. Maybe there’s a real link there, too, but month of birth is hardly the most important thing when it comes to any of these outcomes.

I am a Pisces, but my birthday falls right on the cusp, when the sign is changing to Aries. So am I more likely to be a typical Pisces, all dreamy and artistic, or a hot-headed Aries? Should I spend more time sprinting because of my fast-twitch genes, or attempting marathons because of all the other ones?

You can spend a lot of time analyzing the precise time and location of my birth, and trying to calculate the precise ways my genes interact and which ones are more powerful. Or you can spend time with me, make observations, ask questions. The answers you get through interaction will almost certainly be more correct.

Helix is unlikely to do major harm, but it’s unlikely to help either. I had signed up for one half-marathon in June, skipped it; signed up for another one two weeks later out of guilt, skipped it; thought about signing up for a third, and thankfully didn’t. It was fall when I received my DNA test back, and while the results were interesting, one look out the window made it clear that I wouldn’t even go outside again until April, much less run intervals. Helix could tell me what I could be doing to improve, but it couldn’t do a single thing to help the biggest roadblock to my dream of the half-marathon: my hatred of cold weather.