Find the right blood test for you.

Measures cholesterol carried by small, dense LDL particles. These are more strongly associated with artery disease than larger LDL particles at the same cholesterol level. View details →

Measures reverse T3, an inactive form the body makes from T4. Mainly used in specialist assessment, since it rises during illness in people with normal thyroid function. View details →

Measures total triiodothyronine, the active thyroid hormone, including the portion bound to proteins. Can help assess an overactive thyroid. View details →

Measures how much capacity thyroid hormone binding proteins have left. An older test used with total T4 to calculate the Free T4 Index. View details →

Measures the total amount of testosterone in the blood, including both the protein-bound portion and the small unbound portion. Can help assess conditions related to testosterone levels. View details →

Measures antibodies to thyroglobulin, a protein the thyroid uses to make hormone. Found in autoimmune thyroid disease, and important when interpreting thyroglobulin results. View details →

Measures antibodies to thyroid peroxidase, an enzyme the thyroid needs to make hormone. The main marker of autoimmune thyroid disease. View details →

Measures TSH, the pituitary hormone that tells the thyroid how much hormone to make. Usually the first test used to assess thyroid function. View details →

Measures free T4, the unbound portion of the main thyroid hormone that is available to tissues. Usually interpreted alongside TSH. View details →

Measures TMAO, a compound produced when gut bacteria process nutrients found in red meat, eggs and fish. Higher levels have been associated with cardiovascular risk. View details →

Measures antibodies that bind the TSH receptor on the thyroid. The key test for Graves' disease, the most common cause of an overactive thyroid. View details →

Measures transferrin, the protein that transports iron through the bloodstream. Rises when iron is low and falls with inflammation or poor nutrition. View details →