• Christina Applegate recently learned that she was misdiagnosed with multiple sclerosis (MS).
• Applegate was first diagnosed in 2021 after multiple tests and worsening symptoms.
• About 15% of MS patients are believed to be misdiagnosed, given how complex the disorder is.

After being diagnosed with multiple sclerosis (MS) in 2021, living with severe symptoms, and becoming one of the most famous celebrities with the disorder, Christina Applegate learned some shocking news: She doesn't actually have MS.

In an October 20, two-part episode of her podcast "MeSsy" with Jamie Lynn Sigler (another actor diagnosed with MS), Applegate shared that she took over half a year off from recording the podcast to process the news of her MS misdiagnosis.

According to Applegate, her doctor framed the revelation as a positive update. "She came into my room and said, 'Congratulations, you don't have MS,'" Applegate said in the podcast.

But to Applegate, no longer having an explanation for the pain, balance issues, tremors, incontinence, and fatigue she'd been living with for years felt more like being "back at square one."

"You don't get misdiagnosed and then all of a sudden, I'm better," she said. "If anything, I've gotten worse, in some ways."

Applegate's story is far from a medical anomaly. MS researchers estimate that about 15% of worldwide MS patients are actually misdiagnosed, based on a 2024 meta-analysis of multiple studies.

The risks to patients are two-fold, Dr. Marwa Kaisey, an associate professor of neurology at Cedars-Sinai, who also appeared on the podcast, told Business Insider. "One is thinking you have MS — a lot of the medications we use to treat MS have side effects and risks like infections," she said. "The other category is, if you don't know what you have, then you're not getting treated for your actual diagnosis."

Kaisey and another researcher shared why MS is so challenging to diagnose — and why more people might end up with Applegate's experience in the future.

The race to diagnose a hard-to-diagnose disorder

There is no single blood test that can diagnose MS.

Instead, doctors often piece together an MS diagnosis using a neurological exam (testing balance and reflexes), MRI scans, a lumbar puncture (or spinal tap), and possible blood tests to rule out other conditions such as Lyme disease.

Sometimes, doctors overrely on a single diagnostic, such as an MRI finding, without performing enough other tests, Dr. Andrew J. Solomon, a professor of neurological sciences at the University of Vermont who co-authored the meta-analysis, told Business Insider.

In 2019, Solomon co-authored an MS misdiagnosis study that found that patients who were initially diagnosed with MS were later told they actually had other conditions, such as migraine, radiologically isolated syndrome, spondylopathy, and neuropathy, which can share overlapping symptoms with MS and similar brain scan results.

In the podcast, Applegate revealed that she had a nerve test to rule out peripheral neuropathy, as well as MRIs and a lumbar puncture. While her spinal fluid test showed a low level of immune proteins that can support an MS diagnosis, she had nearly 40 brain lesions and worsening symptoms, leading doctors to diagnose her with MS.

Solomon said MS should be diagnosed by "confirming each element of our diagnostic criteria and ruling out other things," rather than assuming it must be MS if the MRIs and symptoms fit.

The problem is, both physicians and patients are eager to diagnose MS as early as possible, he said. Correctly spotting MS early can lead to better treatment results and a higher likelihood of disability prevention, according to research.

Plus, for patients dealing with a plethora of debilitating symptoms, "a period of diagnostic uncertainty is uncomfortable," he said, even though the best course of action is to wait and perform more tests.

A new testing protocol revealed Applegate's misdiagnosis

In the podcast, Applegate shared that her brain lesions were missing "strings" associated with MS.

It's a finding associated with a new, more accurate diagnostic tool for Kaisey, who also co-authored the 2019 study with Solomon, explained on the podcast.

The central vein sign (CVS), is an MRI biomarker that can help differentiate MS brain lesions from ones associated with other disorders. It refers to a small vein that appears as a dot or thin line through the center of a brain lesion.

CVS was only recently adopted as part of the recommended MS diagnostic criteria, in 2025 — four years after Applegate was first diagnosed with MS. Kaisey told Business Insider that part of her work is expanding education around newer diagnostic tools, noting that not all physicians are using CVS yet.

Solomon hopes more doctors will include CVS in their diagnostic protocols, especially for existing MS patients or those who switch providers without being evaluated by their current doctors. "If something doesn't fit, there's an opportunity there to reevaluate if the diagnosis is right," he said.

Many misdiagnosed MS patients feel exactly like Applegate does

When it comes to learning about an MS misdiagnosis, Solomon said experiences like Applegate's aren't that uncommon.

"I've heard many stories where some doctor was very enthusiastic about telling a patient they actually didn't have MS," he said. "But many of these patients are suffering, and they still have symptoms. So it's not always necessarily a happy thing."

For Applegate, her initial MS diagnosis provided clarity and direction. "That was my answer to everything that was going on," Applegate said. Some might relate to Applegate's "square one" feeling, particularly if their doctor was an MS specialist and won't see them anymore, Solomon said. Without a formal diagnosis, they might also worry about insurance coverage for treatments that have provided some relief.

There is also the emotional part of having an MS diagnosis. "I leaned into other friends, I leaned into the community," Applegate said. "I had a reason as to why my day sucked every day, and now I don't have a reason."

Knowing she doesn't have MS also made her feel like she "let everybody down" after becoming one of the "poster children for MS," she said. It made her wonder if she was somehow imagining symptoms or at fault for her pain.

Given how common MS misdiagnosis is, Solomon believes it's a good thing that Applegate is sharing her story.

"It's kind of wonderful that Ms. Applegate is public with this because if the number is really 15%, you can do the math," he said. "There are a lot of people out there who might ask their doctors about the accuracy of their diagnosis and find out that, in fact, they had something else."

• Ultra-processed foods are everywhere, but some additives are worse than others.
• Elizabeth Dunford is a nutrition epidemiologist who studies additives and health issues.
• She avoids two types of additives when she sees them on a food label.

Elizabeth Dunford isn't trying to make grocery shopping an impossible task.

Dunford is a nutrition epidemiologist who studies additives in ultra-processed foods and their impact on health.

It's not realistic to avoid packaged foods altogether, Dunford, who is based at the University of North Carolina at Chapel Hill, told Business Insider. They make up around 70% of the US food supply.

So, she focuses on buying foods for her family that have a low "additive load" overall.

"I try and avoid things in general that have a lot of additives, but you can't avoid everything," said Dunford, who is a mom of two. "If you pick it up, you turn it over, and you don't recognize half the ingredients, it's probably not a good choice," she said.

She has taught her kids that eating enough vegetables, protein, and calcium will "keep their brains and bodies healthy," and that there's a time and a place for treats, but it's not good to have too many. "It is the everyday food and drink choices that really matter to me," Dunford said.

Ultra-processed foods contain ingredients you wouldn't find in a regular kitchen, like emulsifiers and thickening agents. They tend to be ultrapalatable, meaning they contain an irresistible combination of sugar, salt, and fat, and have long shelf lives. They can be anything from potato chips and soda to packaged bread and yogurt.

A diet high in this type of food has been linked to a higher risk of chronic diseases, including type two diabetes, cardiovascular disease, cancer, and depression.

While she finds it unrealistic to cut out all additives, Dunford shared the two additives that she won't buy.

Synthetic dyes

Dunford avoids buying products that contain synthetic dyes for herself and her family. "I will allow it at a birthday party. That's about it. Day-to-day, they're not allowed in our house," she said.

The dyes, which are typically made from petroleum, are used to give food products colorful appearances. If you're looking out for them on a label, scan for a color and a number.

Dunford said that although the dyes are common in candy and junk foods, they can be used in anything from blueberry bagels to spinach wraps. Instead of avoiding any particular food, she checks labels to find a version without synthetic dyes.

"There are definitely enough alternatives out there that there is no need to buy products for my kids that contain synthetic dyes," she said.

Synthetic dyes are not proven to harm everyone who consumes them, but evidence suggests they can worsen hyperactivity or attention-related behavior in children who are sensitive to them. Dunford said her son is on the ADHD spectrum, and that she would notice a difference in his behavior when he had brightly colored foods.

"My son, like many kids his age on the ADHD spectrum, and I noticed he became horrible when he would have brightly colored foods," Dunford said.

In January 2025, the FDA banned Red Dye 3, a dye that gives foods like candy, frosting, and bacon a cherry red color, because it was linked to cancer in an animal study. It has not been found to cause cancer in humans, but has also been associated with behavioral issues in some children.

In April 2025, the FDA announced that it would be phasing out a number of other synthetic dyes, including Red 40, Green 3, Yellow 5, Yellow 6, Blue 1, and Blue 2.

Phosphate additives

Dunford tries to avoid buying products with phosphate additives such as phosphoric acid, dicalcium phosphate, tricalcium phosphate, disodium phosphate, sodium phosphate, and lecithin.

Studies suggest that phosphate-based additives are present in up to 56% of packaged foods in the US and that they raise blood phosphate levels more than the phosphate that naturally occurs in foods such as meat, seafood, and dairy. Soda, processed meats, and fast food all commonly contain phosphate additives, but they can also be used in everyday staples like yogurt and bread.

Dunford won't buy major culprits like soda at all, but for other products like yogurt, she makes sure to find versions without them.

"Children are getting really highly exposed to these additives and they can really cause a lot of problems with bone health, with kidney health," Dunford said.

The body needs phosphate, which is a mineral, for healthy bones, teeth, cells, and energy production. But too much phosphate in the blood can be harmful, especially for people with chronic kidney disease, whose kidneys are less able to remove excess phosphate.

Calcium and phosphate are both used to build bones, and the kidneys help keep their levels balanced in the bloodstream. When phosphate builds up, it can disrupt this balance and trigger hormonal changes, including higher levels of parathyroid hormone, a hormone that regulates calcium in the blood. Over time, this can cause calcium to be released from bones, weakening them.

Although studies suggest that phosphate additives can temporarily affect the phosphate-calcium balance in healthy people, more research is needed to understand if these ingredients can cause health issues over time. Regardless, Dunford prefers to err on the side of caution.

"You're not going to get it perfect. It's okay, but just take that extra step, look at the label," Dunford said.

• A year after my breast cancer diagnosis, I'm rejecting the "fighter" and "warrior" labels others put on me.
• I'm tired of the pinkwashing that feels like it's turning a terrifying disease into a cheerful marketing campaign.
• I'm grateful for my care and the people who supported me, but I don't need to find a silver lining or turn my experience into an inspirational story.

I was diagnosed with breast cancer a year ago, and with Breast Cancer Awareness Month underway, I have a confession that feels almost sacrilegious: I hate breast cancer culture. I hate the "fighter" and "warrior" labels I didn't ask for, and I especially hate the over-the-top pink branding that I see so much.

I didn't ask to join this club. I didn't want to lose my hair to chemo or have my breasts amputated. I didn't choose to worry about whether my kids and relatives might also develop this horrible disease. And I hate pink; I always have. I'm grateful for my treatment and that I've weathered it all relatively well. I just feel pissed that this was my lot in life.

As I reach the anniversary of the day my "before" split into the "after," I don't know what I'm supposed to call myself now. "Fighter" doesn't feel right. "Warrior" definitely doesn't, and "survivor" is complicated.

I didn't choose to fight cancer

I understand that people mean well when they call someone a fighter. They want to acknowledge what she's enduring and remind her she's strong. Pink ribbons and awareness campaigns can raise money and encourage screenings, and those are all wonderful things. But in the rush to turn cancer into a story about courage and hope, there's little room for the less inspirational feelings: anger, resentment, exhaustion, and fear.

I didn't fight cancer in the way people seem to imagine. I showed up for appointments, followed my doctors' recommendations, and endured treatment because I wanted to live. I didn't have some extraordinary reserve of bravery. I didn't get to opt out. What was the alternative?

I didn't earn a special title by going through chemotherapy. I was a person with a disease who wanted to get better. Sometimes I was scared. Many days, I was exhausted. Sometimes I was just trying to get through the day.

I'm over the pinkwashing of breast cancer

And the pink. Everywhere, pink. Pink products, pink merchandise, pink marketing campaigns. Sometimes the branding feels like a cheerful coat of paint over a genuinely terrifying experience.

Cancer isn't cute. Losing your breasts isn't a lifestyle rebrand or a "free boob-job." Buying a pink water bottle doesn't necessarily make anyone feel less alone in a hospital room.

I don't begrudge anyone who finds comfort in a pink ribbon or a community of fellow patients. My problem is with the expectation that breast cancer should come packaged with a neat, uplifting message. What if I don't want to embrace this experience? What if I don't feel grateful for the lessons it taught me?

I'd happily trade every bit of perspective I've gained for the life I had before my diagnosis.

Finishing treatment doesn't mean everything's over

There's no clear finish line. Treatment ends, and everyone wants to celebrate that you've made it through. You want to celebrate, too. But you're also left processing what happened to your body, what you've lost, and what the future might hold.

As much as I try to go back to my "before" life, I'm constantly holding my breath, waiting for the other shoe to potentially drop.

Before cancer, I didn't spend much time thinking about my identity. I was busy being a mom, wife, sister, daughter, and working woman. Now, I'm still figuring out how much space cancer deserves in my life. I don't want every conversation to be about my health. I don't want people to expect me to inspire them simply because something terrible happened to me.

I'm grateful to be here, but I'm still angry

I'm grateful for my doctors, the people who showed up for me, and the advances in medicine that gave me treatment options. I'm grateful that I've come through this in relatively good shape. But I can appreciate the care I've received and still be furious that I needed it.

As I reach this anniversary, I don't need a label to make my experience meaningful. I don't need to turn cancer into a lesson or find a silver lining in every awful moment. I don't need to be inspirational.

If you want to support someone with breast cancer, you don't have to call her a fighter. Acknowledge that what she's going through is hard. Offer an ear or, better yet, a DoorDash gift card. Let her feel however she feels.

As for me, I'll mark this anniversary with gratitude, anger, uncertainty, and the knowledge that I'm still here. That's enough.

• Hormone testing — especially to monitor testosterone levels — is trendy.
• A startup backed by the US military has pioneered a DIY device that requires no needle.
• It costs less than $100 and is quickly becoming a go-to for biohackers and telehealth brands.

Dr. Jonathan Andrews had never checked his testosterone levels until about six weeks ago. Now, he's a convert. He's already repeated the procedure twice.

He didn't go to a lab for his bloodwork, and he didn't use a standard needle or a finger prick. Instead, he attached a big red button to his bicep, then waited about five minutes while it quietly, almost imperceptibly, drew blood out of his skin while he made breakfast.

Andrews said he loves the "foolproof" process.

This quarter-sized pushbutton, called Tasso+, is being hailed as a game changer. Telemedicine companies, including Hims & Hers, Balance My Hormones, and Maximus Health, all offer the same click button as a way for patients to check their "T" levels from the comfort of home.

Testosterone therapy use has risen steadily in recent years alongside the growth of telehealth and direct-to-consumer men’s health services. Among adults, ages 18 to 34, prescriptions have more than doubled since 2018, according to health data company Truveta, even though the treatment can suppress sperm production and affect fertility.

"Hormones are one of the things that you need to continually track, especially if someone does go on treatment," Andrews, a healthcare investor and urgent care doctor who is not affiliated with Tasso, said. "It is one of the markers that you actually want multiple data points."

One of the best times to check testosterone levels is first thing in the morning, when it can be tricky to get to a lab. Some men around the globe are starting to rely on the red plastic Tasso+ button to track hormone levels more regularly at home, without a trained phlebotomist or needle prick.

"This is the future," DJ and record producer Diplo tells the camera in a YouTube video for Rhythm, a blood testing company using the Tasso+ device, where he's a brand ambassador. "Everybody needs to know what's going on in their body."

It isn't a perfect test, but it's the next generation of DIY consumer health, geared toward diagnosing problems without a doctor or medical technician.

Biohackers want to go beyond wearables

Tasso isn't just for men wondering about their testosterone levels. Menopausal women on hormone replacement therapy and Olympians undergoing drug testing have also tried out Tasso's blood-drawing system.

It's being marketed to longevity-conscious consumers, too, as a way to track progress and assess fitness, with data that goes beyond what you could get from a smartwatch, ring, or scale, including tracking of thyroid function, cholesterol status, and hormone health.

It's US Food and Drug Administration-cleared as a Class II medical device, the green light from regulators that this technology actually works. The blood gets collected by regular folks at home, then packed in an envelope and mailed off to a real lab for analysis (so no, this isn't Theranos promising to analyze a single drop of blood in a little mobile lab the size of a printer).

It's taken 14 years, and over $120 million in investment, including an early VC-style Defense Advanced Research Projects Agency (DARPA) grant from the US military, but suddenly, Tasso+ buttons are showing up across the medical world — and outside it.

"Our goal was to try to make the most patient-friendly blood draw possible," Tasso cofounder Ben Casavant said of the project he started "in a garage" while he was still a biomedical engineering graduate student at the University of Wisconsin-Madison in 2012.

The company has grown quickly since it received FDA clearance for Tasso+ in 2022. Three years later, it announced it had shipped 2 million devices. Over the past year, that number has doubled to 4 million, the company told Business Insider.

The race for decent at-home blood testing is on

Telehealth companies are scrambling to adopt easier ways for people to do routine bloodwork, as the market for consumer blood testing explodes, for longevity, cancer tests, colonoscopy alternatives, and more.

Maximus's at-home testosterone test kit is $99 and includes a Tasso+. Another startup called Rythm Health, the service that Diplo promoted, offers a $79 monthly health check based solely on a Tasso+ draw. Billionaire power couple Jesse Itzler and Sarah Blakely — who founded Marquis Jets, which pioneered the prepaid private jet card, and Spanx, the billion-dollar shapewear company, respectively — are also brand ambassadors for Rythm.

The selling point for the San Francisco startup, launched in 2024, is that patients can track levels of key hormones and metabolic markers that biohackers prize, such as testosterone and estrogen, all on their own, receiving results in days via an app.

The category is quickly catching the attention of leading direct-to-consumer subscription health companies. Hims & Hers, which also offers Tasso+, recently bought a Tasso competitor, YourBio Health, for $153 million. Then there's Liam McNamara, the 20-year-old college dropout who moved to Silicon Valley to "replace a $112 billion blood testing industry" with his early-stage longevity startup called Matrix Bio.

These companies are betting on consumers' desire for a more "quantified self" and for preventative, longevity-focused, self-directed healthcare that's both personal and actionable. Investment bankers at Jeffries estimated in September that the global at-home ("point of care") testing category is growing rapidly, at a rate of about 18% annually, and could be worth $67 billion by 2030.

The drawbacks

While convenient, the technology doesn't have exactly the same benefits as getting your blood drawn by a pro. For most routine blood work, Tasso+ performs just as well as a regular blood draw, but in terms of volume, you can't run as many tests as you can with a needle in a vein.

That classic technique has barely changed since 1947, when American Joseph Kleiner invented the "evacutainer" tube, which is essentially what we still use today.

Tasso uses capillary blood drawn from the skin, not the veins. That means it's inherently less painful, but it collects blood more slowly than venipuncture, and the single-use system is unreliable for capturing some more fragile blood measurements, like potassium levels, or testing for specific proteins related to Alzheimer's.

WFH, but make it blood

On Reddit in recent months, users in the /biohacking forum have been sharing their Rythm results with one another like scores from a video game. One user who posted a photo of a sky-high cholesterol reading wrote that they were persuaded to stop taking oral steroids after seeing their Tasso results.

It's also fast becoming a go-to way for researchers and drugmakers to conduct clinical trials without asking participants to come in regularly for lab tests. Today, the product is used by patients with Parkinson's for genetic research and clinical trial participants testing out drugs from major pharmaceutical companies, including Eli Lilly and Pfizer.

"When we founded the company, this seemed like a no-brainer thing, which is: 'Hey, if you can provide an easy, patient-friendly blood draw, that should be adopted in a way that can help people get access to their health data,'" Casavant said. "To see it happening now, it's really exciting."

• Dr. Katie S. Davis is a clinical neuropsychologist who evaluates children for learning disorders.
• She said some parents are rushing to diagnose their children for normal kid behavior.
• She suggested some softer interventions before booking an evaluation appointment.

Over years of evaluating children for learning disorders, Dr. Katie S. Davis noticed an interesting phenomenon: Some parents seemed visibly disappointed when she told them their kids didn't meet the criteria for ADHD or autism.

"I found that those conversations can be more difficult to have than with a parent whose kid is really disabled and whose needs are very high," Davis, a clinical neuropsychologist and author of "Actually, You're Fine," told Business Insider.

Though she would try to reassure those parents that their concerns about their children's behavior were valid and worth addressing even without a formal diagnosis, "it's not as tangible or concrete as parents want, and they often leave the conversation feeling dissatisfied."

Parent-reported diagnoses of several childhood developmental and learning conditions have increased in recent years. For example, the estimated share of US children ages 3 to 17 with a current ADHD diagnosis rose from 8.6% in 2016 to 10.5% in 2023. Separately, a study of children ages 6 to 17 found parent-reported lifetime learning-disability diagnoses rose 16.4% over the same period.

While some argue that greater awareness of learning disabilities and disorders accounts for the increase, Davis doesn't feel that explains the full story. From what she's observed, ever-growing expectations for kids — and parents desperate for explanations for why their child is lagging behind — also play a role.

She said rushing to a diagnosis can have negative long-term implications for everyone.

"People don't think that ADHD means anything, people don't think dyslexia means anything," Davis said. "Then those people who are truly disabled by those conditions have enough battle to justify their need for accommodations and services."

Higher and higher expectations

In order to qualify for a diagnosis such as ADHD, symptoms must be present in at least two major settings, such as both at home and at school. For autism, they must be persistent across multiple contexts.

But some parents focus on how their child behaves in the classroom, in part due to ever-increasing expectations around academic success, Davis said.

"Doing well in school is no longer good — you have to be at the top of the pack," Davis said, noting that similar patterns have arisen in higher education settings with parents arguing for their teenagers' grades to be inflated. "Parents want excellence, and if it's not excellent, it's bad."

When worrying about their child's behavior, some parents zero in on their child's behavior in class while overlooking how their child compares to others, Davis said.

"If you're in a kindergarten classroom, probably all of the kids to some degree are going to have trouble sitting on the rug for 30 minutes at circle time," Davis said. Most will cluster in the middle of the bell curve, while some will get antsier earlier or later. The kids who consistently stand out compared to their peers are the ones who should probably be evaluated, Davis said.

Otherwise, "for nine kids out of 10, that sounds like a kid in an elementary school."

Labels are a double-edged sword

Whether they're diagnosed with ADHD or not, a child being hyperactive in class isn't a parent's fault. Still, parents can feel like they're personally responsible.

"There is an eagerness to medicalize the feelings of insecurity, because if it's due to a diagnosis, then it's not a knock on your decisions," Davis said.

Whether or not their child is formally diagnosed, Davis warned against treating it as a catch-all explanation for everything your child does.

"Despite our best intentions, if we put a label on the kid and the kid is aware of that label, they are given the message 'there is something wrong with how you are developing,'" she said. Even positive spins, like "ADHD is a superpower," can send a message to the kid that their life will be forever defined by struggle, she said.

It can also imply that symptoms like difficulty focusing or reading can't meaningfully improve with the right interventions.

"We all want to develop resilience in our children, to make them feel like they have agency and control and they're in charge of their own destinies," Davis said. "Especially when kids are very young and don't understand the fluidity of these labels, we could potentially be working against them."

Try softer interventions first

Davis wants to be clear: Diagnoses such as autism and ADHD are real. There are children who are unambiguously and significantly impaired by them in every setting, who need clear support academically and socially. "There are evidence-based interventions at our disposal that are enormously helpful," she said.

However, for parents who believe their child falls into some gray areas, Davis recommended trying a few things before booking an evaluation appointment. She compared it to a young child with a mild fever: A responsible pediatrician would guide parents through modest steps, such as taking a temperature and offering plenty of fluids, before rushing to the ER.

Instead of assuming your child might have autism if they struggle to make friends or always hang out alone at recess, Davis suggested first making other plans with their parents to set up playdates. You can also sign up your child for a karate class or call the school's teacher to see if they can intervene and help the kids play together more.

Alternatively, she said, if you immediately seek out a diagnosis and place your child into therapy and social skills groups, you could be taking away from more enriching social activities.

If a child continues to struggle, Davis recommended getting a neuropsychological assessment — a form of standardized test that is broader than getting an autism or ADHD evaluation.

While not perfect, she said neuropsychological assessments can measure a child's motor skills, sensory processing, attention, cognitive efficiency, language, memory, and social functioning. Their scores are typically compared with norms for peers of the same age.

More importantly, it helps parents know which interventions are the best. "If your kid perceives life to be very stressful or upsetting, they're not making it up. Let's talk about what we can do to support them better in that environment," Davis said. "But we don't need a diagnosis to do that."