How does someone get a skin tag?

1. What a skin tag actually is — plain and medical

A skin tag is a small, soft, usually pedunculated growth made of normal skin and sometimes extra collagen and small blood vessels; it moves easily on its stalk, can be the same colour as surrounding skin or darker, and is classified as benign — not cancer ^{[6] [4] [7]}.

2. Friction is the leading practical explanation

Dermatologists and consumer health sites repeatedly point to mechanical friction — skin rubbing on skin or clothing — as a likely trigger for tags appearing in body folds (neck, underarms, groin, under breasts). Multiple outlets use friction as a primary explanation for why tags cluster in those areas ^{[3] [4] [7]}.

3. Metabolic links: why clusters can matter

Several sources link skin tags to metabolic conditions: obesity, insulin resistance, pre‑diabetes and diabetes are repeatedly associated with higher rates of skin tags. Some dermatologists and clinics warn that sudden clusters of tags — particularly on the neck, armpits or chest — may be a reason to check blood sugar or metabolic markers ^{[3] [8] [1]}.

4. Hormones and pregnancy: transient spikes

Pregnancy and other hormonal states are commonly cited as times when skin tags increase; pregnancy‑related tags often regress after delivery. Authors infer that hormonal changes can affect skin behaviour and growth factors, making tags more likely during those periods ^{[5] [9]}.

5. Genetics and age: background susceptibility

Authors concede the exact mechanism is uncertain and emphasise genetic susceptibility and ageing as background risk factors: experts say the cause “remains unknown” in detail, but genetics seems to play a role and tags become more common with age ^{[2] [1] [5]}.

6. How common are they? Conflicting but consistent picture

Estimates vary by source: Cedars‑Sinai and other clinical pages put prevalence at about half of adults, while UCLA says up to two‑thirds. The difference reflects sampling and how broadly “skin tags” are counted, but all sources agree they are very common ^{[1] [2]}.

7. What the sources disagree on or leave open

Experts agree on associations (friction, obesity, hormones, age, heredity) but disagree on a single unifying cause — several sources explicitly say “the cause remains unknown” ^[2]. The degree to which skin tags are a reliable early marker of insulin resistance is discussed but not settled; some clinics promote screening when clusters appear ^[8], while mainstream patient guides mainly note the association and recommend medical evaluation if tags appear suddenly or change ^{[6] [3]}.

8. Practical takeaways and hidden agendas to watch for

If you get one or a few tags, they are benign; if tags appear suddenly, in clusters, bleed, or change, see a clinician because that may prompt diabetes or other screening ^{[6] [8]}. Beware of commercial sites and clinic blogs that use the metabolic link to push removal packages or tests — promotional language appears in some clinic sources ^{[7] [8]}. Also avoid DIY removal advice: dermatology organizations warn against home procedures and unapproved products ^{[6] [10]}.

9. What removal and follow‑up look like

Medical removal options include excision (cutting), cryotherapy (freezing), ligation (tying off), and electrodesiccation; the AAD and clinical pages recommend dermatology assessment and caution that OTC or DIY methods can cause injury and scarring ^{[6] [11] [10]}.

Limitations: available sources do not present a definitive biological mechanism that explains every case; they offer associations and clinical guidance rather than a single proven cause ^{[2] [3]}. If you want, I can summarize removal pros/cons or list exact signs that should prompt urgent medical review, citing the same sources.