Most of us think of skin tags as a minor nuisance, little bits of skin you can trim or freeze off. But when they cluster or show up more frequently, they can sometimes be a visible clue to deeper metabolic patterns, especially around insulin resistance.
Recent research shows a link between skin tags and markers of insulin resistance and metabolic syndrome. That doesn’t mean skin tags cause disease, but their presence can be a prompt to look deeper. Here’s how it all connects.
The science linking skin tags and insulin resistance
Several clinical studies have found that people with multiple skin tags tend to have higher HOMA‑IR scores, a widely used estimate of insulin resistance, compared with those that don’t have skin tags.
In one comparison of patients with skin tags versus healthy controls, those with skin tags had significantly higher fasting glucose, higher insulin, and higher HOMA‑IR values.
Another study matched people by body mass index and still found higher HOMA‑IR in those with skin tags, and a strong link between skin tag number and metabolic syndrome criteria such as waist circumference.
Some research also shows a link between skin tags and other markers of insulin resistance in children, even independent of body weight.
All of this supports the idea that skin tags can sometimes act as a visible marker of underlying metabolic stress, though not everyone with skin tags has insulin resistance, and not everyone with resistance has skin tags.
The two blood markers you need to look deeper
If you’ve had recent fasting blood tests, you can estimate insulin resistance using two routine measures:
- Fasting glucose – after an overnight fast, usually reported in mmol per litre.
- Fasting insulin – taken at the same time, usually reported in mIU per litre.
These two numbers let you compute the HOMA‑IR index, a standard research and clinical estimate of how hard your body is working to keep blood sugar normal.
How HOMA‑IR is calculated
If glucose is reported in mmol per litre, the formula is:
HOMA‑IR = (fasting insulin × fasting glucose) ÷ 22.5
Example
Fasting glucose: 5.4 mmol per litre
Fasting insulin: 12 mIU per litre
12 × 5.4 = 64.8
64.8 ÷ 22.5 = 2.9
That person’s HOMA‑IR is 2.9 a value that would be interpreted as elevated in most adult populations.
What the numbers actually mean
Reference ranges are not absolute and can vary slightly between studies and populations, but here’s a widely accepted framework:
Below 1.0
Very insulin sensitive, favourable metabolic profile.
1.0 to 2.4 / 2.5
Typical “healthy” range in many populations. In one large reference study of over 2,000 healthy adults, upper normal was 2.4.
2.5 to 3.0 and above
Suggests notable insulin resistance. Many researchers use values above about 2.5–3.0 as an indicator of insulin resistance, though exact cut‑offs differ slightly by population.
Values significantly above that, for example 4 or 5, indicate more marked insulin resistance, often seen in settings such as metabolic syndrome or polycystic ovary syndrome.
Why fasting insulin changes before glucose
This is a key insight that often surprises people:
When tissues start to become less sensitive to insulin, the pancreas simply produces more insulin to keep blood glucose in a normal range. Early on, clinical glucose values can still look perfectly normal, but only because insulin is working overtime to hold them there.
It’s only when the pancreas begins to struggle that glucose rises into the prediabetes or diabetes range.
HOMA‑IR helps reveal this compensatory stage long before glucose alone tells the full story.
Why fasting insulin can be more informative than fasting glucose
Here’s a metaphor that helps:
- Fasting glucose tells you what the system achieved.
- Fasting insulin tells you what it cost to achieve it.
Two people with the same fasting glucose of 5.2 mmol per litre can have very different insulin demands, which reflects very different underlying metabolic health. A high fasting insulin tells you the pancreas is working harder than it should, even if glucose still looks normal.
Bringing it back to skin tags
If someone has:
- multiple skin tags
- central body fat gain
- a family history of type 2 diabetes
- or a rising waist circumference
…and a calculated HOMA‑IR above about 2.5, that pattern becomes a useful prompt to explore metabolic health further.
Skin tags aren’t a diagnosis in themselves. But in the right context, they can be part of a pattern that nudges someone and their clinician to take a closer look.
The good news
Lifestyle changes can improve insulin sensitivity well before they move fasting glucose. Things like:
- regular movement and strength training
- quality sleep
- whole food focused nutrition
- stress management
often show up first as lower insulin demand, which means lowered HOMA‑IR, even while glucose looks stable.
That early window is exactly where we want to catch changes: when they are most reversible and when people have the most choices.
Need help with your bloods? I have a tool which accompanies your results to get an even deeper understanding of what’s going on inside your body – health from the inside out. Reach out if you’d like to know more.