Brief Answer:
Underactive thyroid gland ( hypothyroidism)

Detailed Answer:
Hello,

Welcome to HCM.

Thyroid is an endocrine gland which produces hormones to keep our metabolism active. When this gland is under active, it is referred to as sluggish thyroid or hypothyroidism.
At first, one barely notices the symptoms of hypothyroidism, such as fatigue and weight gain, or may simply attribute them to getting older. But as the metabolism continues to slow, one may develop more obvious signs and symptoms.
Please do not hesitate to ask more queries. I shall be happy to answer them.

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Brief Answer:
Multiple and wide range of symptoms as mentioned below

Detailed Answer:
Hypothyroidism signs and symptom may include:

Fatigue
Increased sensitivity to cold
Constipation
Dry skin
Unexplained weight gain
Puffy face
Hoarseness
Muscle weakness
Elevated blood cholesterol level
Muscle aches, tenderness and stiffness
Pain, stiffness or swelling in your joints
Heavier than normal or irregular menstrual periods
Thinning hair
Slowed heart rate
Depression, Impaired memory and slowing of thought process.
Also there can be enlargement of the thyroid gland. This may not be present in some types.

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