A functional medicine doctor in Seoul with scientific guardrails

What a functional medicine doctor in Seoul does differently

Functional medicine asks why a problem is happening, not only what to call it. That means a longer conversation about when symptoms started, what makes them better or worse, and how sleep, stress, food, activity and environment fit in. At VEI Clinic this approach sits inside internal medicine: history, examination and validated lab tests come first, and conventional treatment is used whenever it is the right answer.

Dr. HyunSung Park is a board-certified internist, a gastroenterology subspecialist and a member of the Korean Institute of Functional Medicine. He sees patients one-to-one in English and has worked in Korea since 2010. His aim is a plan that is personalized, stepwise and measurable, without unnecessary tests or a cupboard full of supplements.

What we evaluate

• Cardiometabolic health: blood pressure, weight and waist, fitness habits, and labs such as CBC, liver and kidney chemistry, fasting lipids, ApoB and Lp(a) when indicated, HbA1c, fasting glucose with or without insulin, and selective hs-CRP
• Energy, thyroid and anemia: TSH with free T4, B12 with related markers if needed, folate, iron studies including ferritin, and vitamin D
• Digestive and food-related concerns: a structured history and selected tests, with elimination and re-challenge when a trigger is suspected
• Women's and men's health: menstrual and PCOS patterns, perimenopause counseling and selected hormones when the result would change management
• Nutrient status: magnesium, zinc or selenium selectively, plus sleep and stress strategies
• Exposures: heavy metal or toxin testing only when your history suggests real exposure

What we avoid, and why

Some popular functional medicine tests have weak evidence. IgG food sensitivity panels, for example, mostly reflect foods you eat regularly rather than true intolerance, and can lead to unnecessary restrictive diets. Large stool profiles and routine saliva hormone panels often produce results that do not change treatment. If a test will not change your plan, Dr. Park explains why and skips it.

The same applies to supplements and IVs. We favor food-first plans and only add supplements with a clear reason, a specific dose and a stop date. High-dose biotin, for instance, can distort some blood tests, so we time labs around it.

What you receive

After your results visit you leave with four practical things. First, a root-cause map that lays out your symptom timeline, likely triggers and priorities. Second, an action plan with protein and fiber targets, a weekly schedule combining strength training and steady aerobic exercise, sleep timing and a short stress toolkit. Third, lab-aware guidance that separates what needs treatment now, what to watch and when to recheck. Fourth, a supplement plan only if it is useful, written brand-agnostically with dose, duration and stop criteria.

Itemized English receipts are available for personal reimbursement, and documentation can be prepared for employers or insurers on request.

Programs and who they suit

Functional care suits people with long-standing symptoms such as fatigue, digestive trouble or poor sleep, and those who want to improve metabolic risk with a detailed plan. It is not a substitute for urgent or specialist care, and it is not the right choice if you are looking for a single test or supplement that explains everything.

• Foundations Reset (6 weeks): core labs, sleep and nutrition basics, quick wins and a minimal supplement plan
• Core Functional Plan (12 weeks): deeper cardiometabolic mapping, gut basics, a structured training template and a stress toolkit
• Deep Dive (12 to 16 weeks): for complex cases such as IBS-like symptoms or recurring fatigue, with selective GI testing and a guided elimination and re-challenge plan

Red flags and limits

We do not promise miracle results, and we do not sell IV drips for detox or longevity. Results depend on consistent changes over weeks to months. Tests that require a hospital, such as endoscopy or CT, are arranged by referral.

Chest pain, severe shortness of breath, stroke signs, persistent vomiting or fainting need emergency care, not a clinic appointment: call 119 or go to the nearest emergency room.