If the scale won't budge no matter how carefully you eat, an underactive thyroid may be part of the story. Hypothyroidism is common in India — especially in women — and it quietly slows the systems that burn energy. But the relationship between thyroid and weight is more nuanced than most people think.
How common is it, really?
A large multi-city Indian study found roughly one in ten adults had hypothyroidism, with women affected far more often than men. Iodine status, autoimmune thyroiditis and genetics all play a role, and many cases go undiagnosed for years.
The classic signs — fatigue, cold intolerance, dry skin, constipation, low mood and unexplained weight gain — are easy to dismiss as stress or ageing. A simple blood test (TSH, often with free T4) settles the question.
Why the thyroid affects your weight
Thyroid hormone sets your basal metabolic rate — the energy you burn just staying alive. When it runs low, that rate falls, and your body also retains more water and salt. The result can be a few kilograms of gain that feels impossible to explain.
But here's the nuance researchers emphasise: most of the weight gain from hypothyroidism is modest, and much of the initial loss after treatment is water, not fat. Treating the thyroid is necessary, but it is rarely the whole answer to stubborn weight.
Treatment first, then strategy
The foundation is correcting the hormone deficit, usually with levothyroxine, dosed and monitored by a doctor until your TSH sits in the target range. Take it on an empty stomach, and keep timing consistent — calcium, iron and even strong coffee can blunt absorption.
Once your levels are stable, the ordinary rules of fat loss apply again. A well-treated thyroid is not a barrier to losing weight; an untreated one is.
Working with your body
Because metabolism can still run slightly slower, small consistent habits matter more than dramatic diets.
- Prioritise protein to protect muscle, which keeps your metabolic rate up.
- Strength-train two to three times a week to rebuild calorie-burning muscle.
- Ensure enough iodine, selenium and iron — deficiencies impair thyroid function.
- Retest your TSH periodically; dose needs change with weight, age and pregnancy.
Key takeaways
- 01Hypothyroidism is common in Indian women and easily missed — a TSH test confirms it.
- 02An underactive thyroid slows metabolism and retains fluid, but weight gain is usually modest.
- 03Correcting hormone levels first makes ordinary fat loss possible again.
- 04Protein, strength training and stable thyroid levels break the plateau.
References
- 1.Unnikrishnan AG, Kalra S, et al. Prevalence of hypothyroidism in adults: An epidemiological study in eight cities of India. Indian Journal of Endocrinology and Metabolism, 2013.
- 2.Biondi B. Thyroid and Obesity: An Intriguing Relationship. Journal of Clinical Endocrinology & Metabolism, 2010.
- 3.Sanyal D, Raychaudhuri M. Hypothyroidism and obesity: An intriguing link. Indian Journal of Endocrinology and Metabolism, 2016.
This article is for general information and is not a substitute for personalised medical advice. Always consult a qualified clinician about your own health.
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