Cold or Heat Intolerance

Feeling unusually sensitive to cold, or unusually bothered by heat, can sometimes point to how the body is regulating its metabolism and temperature. Both can have many causes. This page explains the possible hormone links and why a clinician's assessment matters more than self-diagnosis.

How temperature intolerance can relate to hormones

The body works to keep its core temperature stable, and several hormones influence how much heat it generates and how it responds to its surroundings. Thyroid hormones in particular help set the pace of metabolism, which affects heat production. When metabolism runs slower than usual, people may feel cold more easily; when it runs faster, they may feel hot and sweaty and struggle in warm conditions.

Everyone has their own comfort range, and feeling cold or hot at times is normal. Because temperature sensitivity is influenced by so many factors, it is best understood as a clue rather than a diagnosis.

Which hormones and conditions may be involved

Temperature intolerance is most associated with the thyroid, but other factors can contribute. None can be diagnosed from the symptom alone, but a clinician may consider:

• Thyroid hormones. An underactive thyroid is classically linked with feeling cold, while an overactive thyroid is linked with feeling hot and sweaty.
• The menopause transition. Changing oestrogen levels can produce hot flashes and heat sensitivity.
• Blood sugar and adrenal hormones. Less commonly, conditions affecting these can influence how the body responds to temperature.

This table is illustrative only. These associations are not diagnostic, and patterns vary by person, age, and sex.

Blood tests a clinician might consider

Testing is guided by the whole clinical picture. Depending on the assessment, a clinician might consider:

• Thyroid tests such as TSH to screen thyroid function.
• A full blood count and iron studies, because anaemia can cause feeling cold.
• Blood glucose and general tests, depending on history.

You can read more in our blood tests and hormones sections, and related conditions are covered in the conditions section. See also hot flashes and night sweats.

Non-hormonal causes to keep in mind

Many things affect temperature comfort that have nothing to do with hormones. Anaemia and low iron, poor circulation, being underweight, certain medicines, dehydration, infections, and simply the environment can all play a part. Because these are common, a careful history usually comes before, or alongside, any hormone testing.

When to see a clinician

It is reasonable to seek medical advice when a clear change in how you tolerate cold or heat is persistent or comes with other symptoms such as weight change, palpitations, fatigue, or changes in mood. A clinician can take a history, examine you, and decide whether any tests are warranted. This is far more reliable than ordering tests for yourself, because results only make sense in context. This page is educational and is not a substitute for personalised medical advice.