Gut Microbiome Testing in Korea: How It Differs from a Colonoscopy or a Stool Test

More of our customers now plan the trip around longevity rather than one specific worry, and the gut is where that world is looking. A 2021 Nature Metabolism study of more than 9,000 people found gut microbiomes grow more unique to the individual from about 40 to 50 on — and that among the oldest, a low uniqueness score predicted decreased survival over four years. 

That is an association across a cohort, not a lever you can pull. But it is why a gut test is on the longevity menu at all, and why ours went from an occasional add-on in the spring to one we attach most often. The questions have not kept up.

In August a customer we will call Denise wrote from Vancouver before booking: what does it tell me that a colonoscopy would not? No answer existed in writing anywhere on our site, so it became a phone call. This page is that call, written down.

Macrogen Gut Microbiome Stool Test

The test is the Macrogen Gut Microbiome Stool Test, $189 as of September 2026, one of the extras people add to a package. It sequences the bacteria in a stool sample and reports your microbiome's composition — diversity, the balance of bacterial groups, specific probiotic strains. It is sold as health monitoring, not diagnosis.

Gut Microbiome Kit

Three tests, three different questions

Here is the confusion in one line: "stool test" is a category, not a test. Several examinations run on a stool sample, and they are looking for completely different things.

The one most Americans know is the fecal immunochemical test — FIT, the at-home kit your doctor mails you, the one Cologuard competes with. It looks for hidden blood as a signal of colorectal cancer or polyps. Korea's national screening programme uses it too: 분변잠혈검사, annually, from age 50.

So the microbiome test is a stool test in the same sense that an MRI and an X-ray are both imaging. Same sample, unrelated question. It sequences bacteria. It does not look for blood, it does not see the colon wall, and it is not a cancer screen.

That is Denise's answer. If colorectal cancer is what is actually on your mind, you want FIT or a colonoscopy, and that is a separate question worth reading first. The microbiome test is for the other reason people book — the longevity one.

The kit, and your calendar

One thing here is unlike the rest of the menu: the sample comes before the appointment, not during it. The kit goes to your accommodation in Korea, not your home address, and you hand-carry it in.

Shipping is the part we worry about least. We hold kits in stock and, when timing is tight, deliver them ourselves rather than trust a courier — around Chuseok and Lunar New Year, that is often exactly what happens.

What we cannot compress is the sequence. In August a group of five finished their checkup, asked to add the gut test afterward, and had to drop it — they were flying out that weekend, and there was no longer a before. So tell us at booking.

Whether it belongs in your checkup

We are not clinicians and we will not tell you to add this test or to skip it. What we can tell you is which question it answers, which questions it does not, and what has to happen on which day. If your interest comes from an ongoing symptom rather than curiosity, that is a different kind of visit — say so when you contact us. If you do buy it, ask us about a video consultation to walk through the results.

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About the Author

Donkyo Seo
Co-founder & CEO, Himedi

For the past 9 years, Donkyo has helped international patients navigate Korean healthcare. Himedi is licensed by Korea's Ministry of Health & Welfare (License #A-2016-01-01-2345). 

Sources

• Wilmanski T. et al., "Gut microbiome pattern reflects healthy ageing and predicts survival in humans," Nature Metabolism 3, 274–286 (2021), doi 10.1038/s42255-021-00348-0 — over 9,000 individuals across three cohorts; uniqueness drift from 40–50 years; "having a low gut microbiome uniqueness measure, predicts decreased survival in a four-year follow-up." Observational association, not a demonstrated cause
• Macrogen microbiome testing service description (macrogen.com) — home sample collection; reporting on gut-health and wellness indices, nutrient-metabolism scores, and detection of probiotic strains registered with Korea's Ministry of Food and Drug Safety
• American Cancer Society, colorectal cancer screening tests — "FIT tests check for hidden blood in the stool from the lower intestines"; FIT annually, multitargeted stool DNA every three years
• National Cancer Center Korea, 국가암검진사업 — colorectal cancer: 분변잠혈검사, age 50 and over, annually, with colonoscopy on an abnormal result