If your weight has climbed without an obvious change in eating or exercise, biomarkers are a reasonable next step. There is a short list of common drivers: thyroid, insulin sensitivity, cortisol, and sex hormones in the perimenopausal transition.
Thyroid
Underactive thyroid slows metabolism and can produce gradual weight gain alongside fatigue, dry skin, hair thinning and cold intolerance. TSH, free T4 and free T3 give the fullest picture.
Insulin and metabolic flexibility
Insulin resistance often presents as central weight gain (waist, abdomen, face) that resists calorie restriction. Fasting insulin rises before fasting glucose moves out of range, so insulin is the earlier marker.
Cortisol
Chronic cortisol elevation drives central fat gain (described as 'cortisol belly' in older literature) and sugar cravings. Morning cortisol is the standard starting test.
Perimenopausal hormones
Falling oestradiol and progesterone shift fat distribution, slow basal metabolic rate, and worsen insulin sensitivity. Many women experience meaningful weight gain in perimenopause without any change in diet or activity. Chxhealth is a biomarker and genetic data provider. We do not diagnose, treat or prescribe. Our service supports your wellbeing journey alongside your healthcare professional.
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Frequently asked questions
Will the test tell me why I am gaining weight?
It will show whether common biomarker drivers (thyroid, insulin, cortisol, sex hormones) are out of typical range. Any flagged result is information for a clinical conversation.
What if all my biomarkers are normal?
Other contributors include sleep, stress, medication side effects, undiagnosed conditions and gradual lifestyle drift. Speak to your GP if biomarkers are normal but weight gain continues.
About this article. Educational content. Chxhealth is a biomarker and genetic data provider. We do not diagnose, treat or prescribe. Our service supports your wellbeing journey alongside your healthcare professional. For medical advice about your health or results, please speak to a qualified clinician.
