Understanding Functional Medicine with Dr. Kristin Oja
Written by Melissa Schenkman, MPH, MSJ
Dr. Kristin Oja, founder of STAT Wellness, returns to discuss the fundamentals of functional medicine and how it differs from traditional healthcare. In this comprehensive conversation, she breaks down complex health issues affecting millennials, explains the role of biometric testing, and provides practical guidance for those seeking a more personalized approach to healthcare.
There's often confusion between functional medicine, integrative medicine, and holistic medicine. Can you explain what functional medicine specifically entails?
Dr. Oja: Functional medicine—honestly, I feel like we should just call it medicine, personalized medicine, the best medicine. To me, it's the only way healthcare can be done effectively. Functional medicine is often described as root cause medicine, but what I tell people is that it takes a biology-based approach to care.
Instead of looking at our whole system as separate parts like traditional healthcare does—where you have an endocrinologist for hormones, a gastroenterologist for GI issues, a pulmonologist for your lungs—functional medicine says, "Wait, you are a whole person. All of these systems work together." We take a biology-based approach to figure out where the imbalances are, what caused them, and work on that for lasting healing.
All of us who practice functional medicine at STAT Wellness are conventionally trained medical professionals. We just decided to treat our patients in a different way.
How do functional medicine and traditional medicine integrate? Are there overlaps between the two approaches?
Dr. Oja: Traditional medicine and functional medicine actually go beautifully together, and we often lean into traditional medicine principles. At STAT, we think of it as a pyramid. The base is lifestyle—when we find imbalances or root causes, we always go to lifestyle first. The next tier is supplements and hormones—how do we optimize and get more balanced? The third tier, the peak that we use sparingly, is pharmaceuticals.
We do value medications and have overlap with traditional medicine, but we don't want to just put a band-aid on something without understanding the root cause. We're also very thankful for traditional medicine because we often refer patients out. If someone gets diagnosed with cancer, we want them with the best oncologist. If they have severe heart blockages, we're getting them to a cardiologist.
We feel fortunate to live in the United States with fantastic specialists—some of the best in the world. But we don't want to just treat symptoms. If you're a hammer, you're looking for a nail. If you're a surgeon, you want to operate. We need to take a deeper dive.
What are some of the most pressing health issues you see among millennials, and how can functional medicine help?
Dr. Oja: The top issues I see are energy problems and fatigue, gut health issues, sleep problems, cancer prevention concerns, and maintaining good brain health—especially as we're seeing more dementia and Alzheimer's in people we know.
Let me break down fatigue, which is huge. We're tired typically for one of several reasons: nutritional depletion (either dietary intake or absorption issues), blood sugar spikes and drops throughout the day, or hormonal imbalances. We see a lot of adrenal issues—these are little "top hats" that sit on our kidneys and control how we respond to stress. We live in a very stressed-out culture, and we can't be in fight-or-flight mode chronically and still have optimal energy.
We also see mitochondrial issues due to environmental variables and infections like long-haul COVID, mono, mold exposure, and heavy metals. So with fatigue, we figure out which category it falls into: blood sugar, nutrients, hormones, or mitochondria.
For gut health, Hippocrates said over 2,000 years ago that all disease begins in the gut, and then we forgot about it. Our gut makes 90% of our serotonin, 85% of our immune system starts there, and it's where we absorb all nutrients. One in four people have IBS or irritable bowel syndrome. We've been very sterile, we've been on lots of antibiotics, we have a fiber-depleted diet, and stress hits every one of these areas.
You mentioned brain health as a growing concern. What are you seeing in terms of Alzheimer's prevention?
Dr. Oja: We are seeing much more Alzheimer's than we've seen before, and it keeps rising. There are three big theories we're seeing. First, microplastics—we're seeing more microplastics in our brains and liver, which increased 50% in just the past eight years. This isn't over decades; it keeps growing rapidly.
Second is type 3 diabetes. We all have blood sugar imbalances, and when our blood sugar spikes, it damages our brain. If we're spiking three to four times every day, it's directly damaging the brain.
The third theory is more controversial but interesting. Cardiovascular disease is the number one cause of death in the US, so we've been trying to combat that by getting everyone's cholesterol really low with high levels of statins. But in functional medicine, we know cholesterol plays a role in brain health and cell membrane integrity. So we wonder: are we having to choose between our heart and our brain in some situations?
We run APOE testing to assess genetic risk for Alzheimer's, and we focus on addressing microplastics, blood sugar issues, and other toxins as preventive measures.
A 2021 Harris poll showed that 44% of older millennials had been diagnosed with at least one chronic condition. Can functional medicine still help someone who's already been managing a condition through traditional medicine for years?
Dr. Oja: Absolutely. We even have patients who start coming to us at 65 wondering what's happening in their body and wanting a different approach. It's never too late.
We have many people come in with PCOS who've been on birth control and metformin to manage it, but they have no idea what PCOS actually means in their body. What's happening hormonally? What lifestyle changes can help them get out of PCOS and potentially off medications?
No matter what age you are, no matter how many diagnoses you have, no matter how many medications you've been on, functional medicine can absolutely help. Our goal is to get people off medication when possible. It doesn't always work, and sometimes medication is necessary, but at the very least, we want people to understand why they're taking it, what the root cause is, and what lifestyle factors can help.
For example, if you have a thyroid issue and you're on levothyroxine, maybe we can't stop the medication, but why did you develop the thyroid issue? How do we work on that so you're not needing more and more medication over time?
Can you walk us through how you approach a specific condition differently than traditional medicine?
Dr. Oja: Hypothyroidism is a great example. The thyroid sits in your neck—it seems simple but is actually fairly complex. In the traditional model, you go in once a year and they check your TSH (thyroid stimulating hormone). But TSH is only how your brain talks to your thyroid—it's the signaler, not your actual T4 or T3 thyroid hormones that are circulating.
Let's say they find your TSH is 10, so you have hypothyroidism. They figure out the right weight-based dose of levothyroxine, recheck to see if thyroid looks good, and then see you once a year. You're left wondering where this came from, but you're told to just take the medication.
In functional medicine, when someone comes to us with hypothyroidism, we look at the whole health timeline—birth, childhood, everything. The thyroid is typically sluggish for one of three reasons:
First, is it autoimmune? Seventy-five percent of women with hypothyroidism have Hashimoto's, which is autoimmune, but they don't often check thyroid antibodies unless you're hyperthyroid. If it's inflammatory and autoimmune, treatment is very different.
Second, is it adrenal-driven? Your hypothalamus and pituitary communicate with both your thyroid and adrenals. If you have adrenal issues, you can have thyroid issues.
Third, nutritional deficiencies. Your thyroid needs iodine, zinc, B vitamins, and iron.
We might discover in your history that you had mono really badly at 15 and struggled with fatigue for two years after—and mono is a big driver of Hashimoto's. We also know gluten contributes to Hashimoto's, so we'll test for gluten sensitivity. Sometimes eliminating gluten can bring thyroid antibodies down, and you might be able to reduce medication.
If it's adrenal-driven, we look at cortisol, DHEA, and pregnenolone, and examine lifestyle factors. Maybe it all started after you had a baby and weren't sleeping, then decided to train for a marathon while getting a work promotion. That's a perfect storm for adrenal dysfunction affecting your thyroid.
What type of testing should someone expect at their first functional medicine appointment?
Dr. Oja: We do both traditional tests and functional tests. When I say traditional tests, I mean through LabCorp with insurance coverage, but we use different markers than typical conventional medicine.
For all patients: We check B12, folate, magnesium, vitamin D, pregnenolone, cortisol, DHEA, and full thyroid panels (TSH, T4, T3).
For females: We test hormones despite being told "we don't test hormones because they change daily." Hormones are complex and change daily, but we're not going to use that as a reason not to test them.
My pet peeve is when patients have had cortisol tested at noon or 1 PM. Cortisol rises in the morning and gradually decreases, so timing matters enormously. We want everything done within one to two hours of waking, fasted, no exercise, no coffee—only water.
For functional tests, we do comprehensive stool tests because we can't evaluate your gut microbiome well through regular labs. We use Dutch urine tests to see estrogen metabolites for breast cancer risk, fibroids, endometriosis, and fertility issues. We run micronutrient tests that show antioxidants, methylation, mitochondrial function, fatty acids, and heavy metals in one test.
But we always tell patients we want to meet them where they're at budget-wise. Not everyone needs $5,000 worth of testing. Maybe they just need to go to bed earlier, eat more vegetables, and take some deep breaths during the day.
You also offer biometric screening like body composition and VO2 Max testing. How do these fit into the overall health picture?
Dr. Oja: We don't like to focus on weight at all because we know BMI is problematic, but we do know muscle is our greatest asset as we age. With body composition testing, we want to ensure you have 100% of the muscle mass you need in all extremities—legs, arms, trunk—for longevity. We also look at symmetry and balance between right and left sides.
We examine body fat percentage within reason. If you have higher body fat as a female, you might have higher estrogen and more inflammation, which clues us into looking at labs differently. We also look at resting metabolic rate, and my favorite marker is visceral fat—the deep fat around your organs that you can't see. You could be a size 0 or size 10, and your visceral fat could be very different depending on food quality, metabolic health, and lifestyle. It's strongly correlated with heart disease and stroke.
VO2 Max testing shows how well you use oxygen when you exercise and indicates cardiovascular health. It helps us determine if you're training in the right zones. I've mentioned adrenal burnout several times, and understanding your VO2 training zones can help you perform better while ensuring we're seeing improvements in cardiovascular health—important since heart disease is the number one cause of death in the U.S.
Supplements are a hot topic among millennials. What role do they play in functional medicine?
Dr. Oja: We love supplements—they're the next tier after lifestyle. Part of this comes from the reality of our world: our soil isn't as nutritionally dense as it used to be, and we're protecting our skin from cancer with sunscreen, which blocks vitamin D synthesis.
We try to keep it to 2-5 supplements maximum of the most important things based on individual needs and goals. Every supplement that's ever been made has shown some benefit somewhere, but the question is: is it what you need right now with what's going on in your body?
We don't want people overlooking the basics—sleep, stress management, digestion, fiber, hydration, relationships, laughter—while taking 25 supplements a day. Sometimes patients bring in bags full of supplements, and when I ask if we recommended all of them, they say they saw ads and decided to try them. I don't want to be supplement-tweaking instead of addressing root causes, just like I don't want to be medication-tweaking.
We love supplements, we often need them for optimization, and they can be very helpful. But just because something is good for you doesn't mean you need it right now.
How does functional medicine work with health insurance, and what should people expect cost-wise?
Dr. Oja: Our bread and butter is our membership model. We try to make it very approachable and inclusive. Our medicine membership is $185 per month, and you get five functional medicine visits per year, unlimited health coaching, unlimited dietitian consultations, unlimited body composition scans, supplement discounts, educational events, and community outreach.
We really tried to make it comparable to what you'd pay for a gym membership while being very inclusive. You won't find prices like that anywhere else in the nation—we make decisions based on patient experience, not profit and loss statements.
For labs, because they're run through insurance, it depends on your deductible. Some people are surprised when their labs are covered 100% in November but they get a $300 bill in January after their deductible resets.
My financial wellness tip: get an HSA if you're interested in this kind of medicine. You can put $8,000-$8,500 as a family pre-tax, and use it like a credit card for visits, supplements, IVs, and injections. Pre-tax money makes a huge difference.
For people who don't live near STAT Wellness, what should they look for in a functional medicine practitioner?
Dr. Oja: Go to the Institute of Functional Medicine website and use their provider database. That's where my board certification is from, so at least they've had similar training.
But not all functional medicine is the same. Here are my red flags:
If you go for a first visit and they tell you the only way you'll get better is by doing three functional medicine tests plus LabCorp labs, that's a problem. We would never do more than one or two functional tests, and usually only if patients really want them.
If your first visit is going to cost $5,000, that's a red flag. Functional medicine shouldn't be that expensive. Yes, it's more expensive than your once-yearly insurance-covered visit, but it shouldn't be prohibitive.
Another red flag is if they hand you a basket full of 20 supplements when you're leaving. Functional medicine is root cause and lifestyle first. We've moved everything to an online platform where patients can review recommendations and decide what to purchase without pressure.
Look for practices that offer free consultations. At STAT Wellness, we do free 15-minute consults so you can get a feel for the rapport and personality fit. Use the IFM provider search as your starting tool.
What's the most important thing you want people to understand about functional medicine?
Dr. Oja: Functional medicine is about treating you as a whole person, not a collection of symptoms. It's about understanding that all your body systems work together and finding the root causes of your health issues rather than just managing symptoms.
Whether you're 25 or 65, whether you have one chronic condition or several, functional medicine can help improve your quality of life. The goal is optimization—helping you become the best version of yourself through personalized care that addresses your unique biology, lifestyle, and health goals.
Don't overlook the basics while chasing complex solutions. Sometimes the most powerful interventions are better sleep, stress management, proper nutrition, and community connections. But when you need deeper investigation, functional medicine provides the tools and perspective to get to the root of what's happening in your body.
Want to hear more from Dr. Oja? Listen to the YMyHealth podcast!