Free insulin, a critical biomarker in diabetes research and management, refers to the fraction of insulin in the bloodstream that is not bound to proteins, making it readily available to regulate blood sugar levels. This marker provides a more accurate representation of insulin activity compared to total insulin, which includes both bound and unbound forms.

Light chains are proteins produced by immune cells called plasma cells. Also called kappa light chains, they link together with other proteins (heavy chains) to form immunoglobulins (= antibodies) that target and neutralize specific threats to the body (= bacteria & viruses).

Light chains are proteins produced by immune cells called plasma cells. Also called “Free Lambda Light Chains” they link together with other proteins (heavy chains) to form immunoglobulins (= antibodies) that target and neutralize specific threats to the body (= bacteria & viruses).

Free Light Chains, Type Lambda (Serum) measures the amount of unbound lambda light chains circulating in the bloodstream. Light chains are components of immunoglobulins (antibodies) produced by plasma cells, and they exist in two types — kappa and lambda. Normally, small amounts of free light chains are present in the blood, but elevated levels of lambda free light chains may indicate an abnormal plasma cell proliferation, such as multiple myeloma, AL amyloidosis, or monoclonal gammopathy of undetermined significance (MGUS). When interpreted together with free kappa light chains and the kappa/lambda ratio, this test helps distinguish between polyclonal (nonspecific immune activation) and monoclonal (clonal plasma cell disorder) patterns. A normal or low lambda concentration generally suggests the absence of a monoclonal process, though results should always be interpreted alongside other laboratory data and clinical findings.

A T3 (=triiodothyronine) test is a blood test that helps diagnose thyroid conditions, specifically hyperthyroidism (overactive thyroid). Healthcare providers typically order this test alongside other thyroid function tests.

High or low T3 levels may indicate an overactive or underactive thyroid.

According to the American Thyroid Association (ATA), T3 tests are most useful for diagnosing hyperthyroidism. They are less helpful in diagnosing hypothyroidism.

Healthcare providers test T3 levels using blood tests. 

The tests for free T3 are generally less accurate than for total T3.

Free T3 or total T3 blood tests may be ordered to evaluate thyroid function if a thyroid disorder is suspected. They may also be used to evaluate pituitary gland problems, assess the severity and type of thyroid disease, and monitor treatment for a thyroid condition.

Free T4, or free thyroxine, is an essential thyroid hormone that plays a crucial role in regulating metabolism and overall health. While conventional thyroid function tests typically measure Free T4 in blood samples, it's less common to assess Free T4 in dried urine tests. Dried urine tests are more commonly used to measure certain other hormones and metabolites.

T4 (thyroxine) is the predominant hormone produced by the thyroid gland. It is an inactive hormone and is converted into its active form, T3 within cells. Free T4 is the non-bound fraction of the total T4 circulating in the blood.

Testosterone is the primary male sex hormone in humans. A healthcare professional may order a free testosterone blood test if you’re experiencing sexual problems or a secondary condition, like hyperthyroidism, is suspected.  

Free Testosterone is the bioavailable form of testosterone, a key androgen hormone responsible for regulating numerous physiological processes in both men and women. The Free Testosterone - Saliva test measures the amount of unbound testosterone in saliva, expressed in picograms per milliliter (pg/mL). Unlike total testosterone tests in blood, saliva testing specifically assesses the hormone’s biologically active fraction, which is readily available for use by the body’s tissues.

A free testosterone test for men is a critical diagnostic tool in evaluating and managing a variety of health conditions, primarily those related to hormonal balance and reproductive health. Testosterone, a vital male hormone, plays a significant role in several physiological processes including muscle mass and strength, bone density, fat distribution, and sexual function. While total testosterone measures the overall level of the hormone in the blood, free testosterone specifically refers to the fraction of testosterone that is not bound to proteins in the blood and is therefore biologically active and readily available to tissues.

A free testosterone test for men is a critical diagnostic tool in evaluating and managing a variety of health conditions, primarily those related to hormonal balance and reproductive health. Testosterone, a vital male hormone, plays a significant role in several physiological processes including muscle mass and strength, bone density, fat distribution, and sexual function. While total testosterone measures the overall level of the hormone in the blood, free testosterone specifically refers to the fraction of testosterone that is not bound to proteins in the blood and is therefore biologically active and readily available to tissues.

Although Testosterone is generally viewed as a male-only hormone, women’s ovaries also make small amounts of testosterone. It helps many organs and body processes in women. Free testosterone and albumin-bound testosterone are also referred to as bioavailable testosterone. This is the testosterone that is easily used by your body.

Although Testosterone is generally viewed as a male-only hormone, women’s ovaries also make small amounts of testosterone. It helps many organs and body processes in women. Free testosterone and albumin-bound testosterone are also referred to as bioavailable testosterone. This is the testosterone that is easily used by your body.

Thyroxine is a hormone produced by the thyroid gland. The term “free thyroxine” means the measured thyroxine that is not bound to proteins in the blood.

The free T4 index (FTI) is a blood test used to diagnose thyroid disorders. T4, also called thyroxine, is a thyroid hormone. The test measures how much of it is in your blood to help determine whether your thyroid gland is underactive (hypothyroidism) or overactive (hyperthyroidism).