Adults with acne had 55% Cutibacterium on the forehead in 2026 data, versus 24% in healthy controls, a 127% relative elevation. A PMC-listed 2026 journal article reported the regional facial microbiome finding.
But the same report found a different pattern on the nasal dorsum, the bridge area of the nose. Healthy controls had 58% Cutibacterium there, while acne subjects had 52%, and the difference was not statistically significant.
The nose comparison moved in a different direction
The 2026 article reported an adjusted q value of 0.043 for the forehead comparison after correction for 6 comparisons. On the nasal dorsum, the adjusted q value was 0.72, which the authors reported as no significant change.
Take a 32-year-old who notices forehead bumps calming while the nose still looks oily before a work call. These data do not diagnose that person. They explain why one facial zone can carry a different bacteria signal from another.
Swabs can separate acne spots from nearby skin
Cutibacterium is the bacterial group that includes C. acnes, a microbe often discussed in acne research. A separate PMC-listed 2024 pilot trial used long-read V1 to V9 16S rDNA metagenomic testing, C. acnes quantitative PCR, and strain-level ribotyping.
That 2024 trial enrolled 32 adult acne patients over 18 with facial acne graded 1 to 3 on the Investigator Global Assessment scale. The scale is a clinician rating used in acne studies to group visible severity.
Lesional means an area with an acne spot. Non-lesional means nearby skin without a visible spot. For adults checking the mirror by forehead, cheek, nose and jaw, that design keeps the focus on where the skin is acting up.
Thirty-two adults were followed for 2 months
The 2024 pilot trial collected facial swabs at baseline and again after 2 months. It separated lesional and non-lesional areas, so the workflow could compare visible acne spots with nearby skin on the same face.
Its skin workflow included long-read V1 to V9 16S rDNA metagenomic testing. In plain English, that reads bacterial genetic material. The trial also used quantitative PCR for C. acnes, which measures a targeted bacterial signal.
For strain-level analysis, the 2024 paper measured C. acnes and S. epidermidis ribotyping and quantitative levels. S. epidermidis is another common skin bacterium. The point for adults with breakouts is that acne research can look beyond one all-over face average.
Why did the study map matched facial areas?
The 2026 article said researchers performed area-matched intergroup comparisons. They averaged bilateral symmetric areas, including the forehead, cheek and jaw, per subject to avoid pseudoreplication, which means counting related samples as if they were fully separate.
The authors assessed group differences with the Mann-Whitney U test and BKY FDR correction for 6 multiple comparisons. In plain English, the face-map method checked each area against its matching area instead of treating the whole face as one surface.
Every forehead and nose value in the report
The regional comparison supplied 4 source values for the forehead and nasal dorsum. The table keeps the source percent-scale values so the zone-by-zone gap is visible.
| Facial zone and group | Relative abundance, source percent scale |
|---|---|
| Forehead, healthy controls | 24.17 |
| Forehead, acne patients | 54.89 |
| Nasal dorsum, healthy controls | 57.89 |
| Nasal dorsum, acne subjects | 52.35 |
What this means for you
If your forehead, nose, cheeks or jawline seem to break out on different schedules, track your skin by area. Note where spots appear, where oil builds, and where redness lingers after a breakout.
Do not treat this as a home diagnosis of bacteria levels. A dermatologist or pharmacist can help you choose and use acne treatments such as benzoyl peroxide, adapalene, azelaic acid or prescription options in a way that fits your skin.