Functional Medicine · Costa Mesa & Orange County
Your labs are “normal.” So why do you still feel terrible?
If you're exhausted, foggy, and not yourself — but keep being told nothing's wrong — there's usually a reason conventional medicine keeps missing it. Dr. Kristi Vaughan finds the root cause and builds a plan around you.
- Root-cause approach
- 1-on-1 with Dr. Vaughan
- Advanced functional testing
You're not imagining it
You deserve more than “everything looks fine.”
You've been to the appointments. You've heard “everything looks fine” more times than you can count. But you know your body — and something is still wrong. That gap between how you feel and what your labs say is exactly where root-cause functional medicine begins.
If any of that sounds familiar, you deserve a practitioner who looks deeper — and actually listens.
- Exhausted no matter how much you sleep
- Brain fog that makes simple tasks feel hard
- Weight that won't budge despite doing everything right
- Bloating, discomfort, and gut issues written off as “stress”
- Handed another prescription instead of an answer
- Told it's “just your age” or “all in your head”
The Vaughan Vitality Roadmap
A root-cause approach, built entirely around you
Functional medicine uses a science-based approach and diagnostic testing to focus on the underlying factors driving your symptoms — not just the label you were handed. Here's how your care unfolds.
- 01
Free Health Assessment
A relaxed, no-pressure conversation about your history, symptoms, and goals — so we understand the whole picture before anything else.
- 02
Comprehensive root-cause testing
Science-based diagnostics — blood work, food sensitivity, heavy-metal, mold, and adrenal & hormone testing — to reveal what standard panels overlook.
- 03
Your personalized plan
Dr. Vaughan designs an individualized plan around your labs, your body, and your life — never a copy-paste protocol.
- 04
1-on-1 guidance & support
Ongoing, individualized coaching and retesting, so you understand your body and stay on track long term.
What we help with
When “normal” labs don't match how you feel
Dr. Vaughan works with the persistent, hard-to-explain symptoms that conventional medicine often overlooks — tracing them back to their root cause.
Chronic fatigue & low energy
Wiped out despite “normal” bloodwork and enough sleep.
Brain fog & cognitive decline
Trouble focusing, forgetfulness, and mental cloudiness.
Thyroid imbalance
Fatigue, weight changes, and mood shifts tied to thyroid function.
Digestive & gut issues
Bloating, discomfort, and irregularity dismissed as stress.
Autoimmune & inflammation
A body that seems to be working against itself.
Hormone imbalance
Energy, mood, sleep, and weight that feel out of sync.
Environmental toxicity
Mysterious symptoms linked to mold or heavy-metal exposure.
Chronic illness & Long COVID
Lingering, complex symptoms that never fully resolve.
Get to the root cause — then build the plan around the person, not the diagnosis.
Meet your practitioner
Meet Dr. Kristi Vaughan
DC, BCN, IFMCP · Functional Medicine Practitioner
Dr. Kristi Vaughan is a functional medicine practitioner in Costa Mesa serving all of Orange County. She completed her doctoral training at Southern California University of Health Sciences, specializing in functional medicine, nutrition, and chiropractic — and holds certification through the Institute for Functional Medicine (IFMCP).
Her approach is personal because her story is. Dr. Vaughan navigated her own root-cause health journey — heavy-metal and mold toxicity and subclinical thyroid dysfunction — the kind of “your labs are normal” experience so many of her patients know all too well. It's why she looks at the big picture instead of a single number.
Today she helps patients with thyroid, autoimmune, gut, hormonal, cognitive, and environmental-toxicity concerns get to the root of what's driving their symptoms — one individualized plan at a time.
Patient stories
Real people who finally felt heard
“Dr. Vaughan is the first of 7 doctors that actually showed compassion and ultimate care for my symptoms. She spent an extra hour with me and is proactive at helping me get to a better state of living. I love the holistic approach.”
Christopher S.
Chronic pain & feeling dismissed
“I wanted to find the root cause of my hormone imbalance instead of just taking a prescribed synthetic hormone. She's helped me improve everything from my TSH levels to my energy and sleep. If anyone wants to dig deeper into root causes, Dr. Vaughan is absolutely the one.”
Morgan H.
Hypothyroidism & hormone imbalance
“I've dealt with a number of chronic health issues since high school and I'm very particular about who I partner with. Each week I'm feeling healthier and healthier. She has a strong, science- and data-based approach, is an excellent listener, and treats the whole person.”
Cara C.
Chronic health issues
“I was diagnosed with Graves' disease just over a year ago. A few months after starting with Dr. Vaughan, my Graves is stable and I've learned my triggers. Although I was skeptical, it's been great to get off the roller coaster.”
Antonietta S.
Graves' disease (autoimmune)
“I had various digestive issues — gas, indigestion, difficulty eating certain foods. After one visit and following her suggestions, I've been symptom-free these past few months. I whole-heartedly believe in the methods Dr. Vaughan uses.”
Phil J.
Digestive issues
“Because she works on the physical and mental body, she is able to help on many levels. Her ability to diagnose and treat is almost magical. I am very fortunate to have found her.”
Kelly R.
Whole-person care
Credentials & authority
Care backed by real credentials
Dr. Vaughan's work is recognized by her peers and grounded in advanced functional-medicine training.
- Doctor of Chiropractic (DC)
- Board Certified in Nutrition (BCN)
- IFM Certified Practitioner (IFMCP)
- Author of “Thyroid Track”
Recognized by her peers
- 2023 Women in Medicine — Top Functional Medicine Practitioner
- 2020 Top Doctor Award
- 2016 Award of Excellence in Holistic Medicine
Author of “Thyroid Track”
Dr. Vaughan literally wrote the book on tracking and understanding thyroid health — a resource born from the same root-cause approach she brings to every patient.
Take the first step
Ready for answers instead of another shrug?
Book your free health assessment and find out whether a root-cause, 1-on-1 approach is right for you. No insurance required, no pressure — just a real conversation about how you feel and what's driving it.
Prefer to talk first?
(714) 434-9355Questions & answers