You may be able to recite your latest cholesterol test numbers off the top of your head, but what about other crucial blood test results? Here are 13 key numbers that have a major impact on your health that you need to know, and why.


Thyroid Stimulating Hormone (TSH) levels above 2.5 are considered to be suspicious for subclinical hypothyroidism by many integrative physicians.

The “normal” reference range for the TSH test tends to run from .3 to 4.5, and many patients with levels above 2.5 are told their thyroid is “normal,” while their physicians fail to test to actual circulating thyroid hormone (Free T4, Free T3) or the thyroid antibodies that can detect a thyroid under autoimmune attack.


The Free T4 test measures the available amount of the T4 storage hormone available to be converted into T3, the active thyroid hormone.

While the reference range at many labs runs from .8 to 2.8 ng/dL, integrative physicians have found that most patients feel best when their level falls into the top half of the range, at a level of 1.3 or higher.


The Free T3 test measures the available amount of the active T3 thyroid hormone circulating in the bloodstream. While the reference range at many labs runs from 2.3 to 4.2 pg/mL, integrative physicians have found that most patients feel best when their level falls into the top half of the range, at a level of 3.2 or higher, and in many cases, at 3.7 or higher.

BELOW 24 ng/dL / BELOW .37 nmol/L

Reverse T3 is a measure of the amount of T4 that is converted into a biologically inactive form of the T3 hormone. Integrative physicians have found that elevated levels of Reverse T3 may suggest that thyroid hormone is not properly converted from T4 into T3, for use by the cells, and may result in hypothyroidism symptoms despite otherwise “normal” levels of Free T4, Free T3 and/or TSH.


Levels above 9.0 IU/mL on the Thyroid Peroxidase Antibodies (TPO) test are considered to be evidence of the autoimmune disease Hashimoto’s thyroiditis, the primary cause of thyroid problems in the United States. Interestingly, many conventional physicians test only the TSH – Thyroid Stimulating Hormone – but fail to test for TPO, and do not accurately diagnose Hashimoto’s disease in its earlier – but still often symptomatic – stages.


A level of 50 or higher — for a reference range of 20-100 – is considered by many integrative physicians to be a minimum level for Vitamin D for the general population. Still, many patients who are tested by conventional physicians and have Vitamin D levels of 20 to 50 are told their results are “normal.”


When the reference range is approximately 20 – 100, 80 is the optimal level for ferritin — a form of stored iron — for women who are struggling with hair loss and hormonal imbalances.


This is the conservative estimate of the percentage of women who will develop a thyroid condition by age 60. Some experts believe that this number is in fact much larger.


This is the total number of diseases that are classified as “autoimmune.” They include more common autoimmune diseases, including Hashimoto’s and Graves’ thyroid diseases, Multiple Sclerosis, Rheumatoid Arthritis, and Psoriasis, as well as dozens of others. Having one autoimmune disease increases your risk for developing another, and autoimmune diseases can run in families.

The American Autoimmune Related Diseases Association has a comprehensive list of diseases that are categorized as autoimmune.


More than 2 million prescriptions each year are written in the United States for natural desiccated thyroid drugs — including Armour Thyroid, Nature-thyroid, WP Thyroid, and the Acella-made generic natural thyroid drug. Natural thyroid drugs contain natural forms of the thyroid hormones T4 and T3, as well as other co-factors, and some patients and practitioners find them more effective than the conventional hypothyroidism treatment, levothyroxine (a synthetic form of the T4 hormone.) (Some common brands of levothyroxine include Synthroid, Levoxyl, and Tirosint.)

LESS THAN 100 mg/dL

The Fasting Blood Sugar (FBS) or Fasting Glucose test measures blood sugar levels. When levels are elevated, this can indicate prediabetes, insulin resistance, or metabolic syndrome, and make weight loss more difficult.

Less than 100 mg/dL is considered normal, however some integrative physicians feel that levels above 90 may point to some degree of insulin resistance. Conventional diagnosis finds levels between 110 and 125 mg/dL to indicate impaired fasting glucose and prediabetes, and levels above 126 mg/dL on several tests can diagnose Type 2 diabetes.


The Hemoglobin A1C (A1C) test measures average blood sugar levels for the past two to three months. Elevated levels can indicate a risk of blood sugar abnormalities and diabetes, and contribute to difficulty losing weight.

Below 5.7 is considered normal. An A1C between 5.7 and 6.4 percent indicates prediabetes and/or metabolic syndrome. An A1C level of 6.5 percent or higher on several tests can confirm a diagnosis of Type 2 diabetes.


Leptin is a hormone that is produced by fat cells in the body, and a key control of metabolism of fat and hunger in the body.

People with normal weight will typically have leptin levels below 10, although most major labs use a reference range of 1 to 9.5 for men and 4 to 25 for women. Levels above 10 may suggest leptin resistance, which means the body believes it is starving, and works to increase fat stores and fails to burn stored fat.

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