Understanding TSH Levels: Normal Ranges & Thyroid Health

Normal thyroid stimulating hormone (TSH) levels vary depending on a person's age and stage of physical growth. Infants and children have higher TSH levels than adults and adolescents. Abnormal TSH levels may indicate a current or potential unhealthy thyroid condition.

Identification

• Thyroid stimulating hormone levels are measured to test the overall function of the thyroid, a gland that controls metabolism and hormone regulation in the body.

Abnormal TSH Levels

• High TSH levels may indicate a condition known as hyperthyroidism (overactive thyroid), while low TSH levels may indicate a hypothyroid condition (underactive thyroid).

Normal TSH Levels in Adolescents and Adults

• The normal TSH level for adults and adolescents who have reached puberty have is between 0.5 to 4.8 units per milliliter (uU/mL) of blood serum.

Normal TSH Levels in Children

• Children who have not yet reached puberty have TSH levels of between 0.6 to 5.5 uU/mL of blood serum.

Normal TSH Levels in Infants

• Full-term infants at four days of age have normal TSH levels of between 1.3 and 16 uU/mL of blood serum; at one to eleven months of age, full-term infants have normal TSH levels of between 0.9 and 7.7 uU/mL of blood serum.