Why test for weight gain?
Unexplained weight gain can indicate thyroid dysfunction, insulin resistance, hormonal imbalances, or metabolic issues. If diet and exercise aren't producing expected results, blood tests can reveal whether an underlying medical condition is contributing — allowing targeted intervention rather than guesswork.
Recommended tests
Thyroid function
Compare pricesHypothyroidism slows metabolism and is one of the most common causes of unexplained weight gain
Diabetes check (HbA1c)
Compare pricesInsulin resistance and pre-diabetes cause the body to store more fat, especially around the abdomen
Hormone profile
Compare pricesLow testosterone (men) or hormonal shifts (women) can drive weight changes
Lipid profile
Compare pricesAssesses cardiovascular risk often associated with metabolic weight gain
When to see your GP
If you've gained weight rapidly without dietary change, notice swelling in your face or limbs, or have a family history of thyroid disease, consult your GP.
Why test for weight gain?
Symptom-led matching
See the tests commonly used to investigate this symptom
UKAS accredited labs
Every listed provider uses UKAS-accredited UK laboratories
Clear turnaround
Typical result times shown alongside price and biomarker coverage
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