Measure Hormones in Blood Spot Test



Reliable, Accurate, Easy-to-Use!




A blood spot test can now measure bioavailable hormones.

I’m excited to announce that we're offering a new type of blood spot test that accurately and more easily than ever, measures female and male hormone levels. ZRT Lab founder and CEO Dr. David Zava has come up with a method for measuring bioavailable hormones in capillary blood that is obtained with a nearly painless finger stick.

Some of you will want to continue using saliva to test your hormone levels, and others will prefer the blood spot test. How do you choose? It depends on which sounds easiest to you: spitting into a tube to collect saliva or a finger stick to collect a few drops of blood.

The new Female Hormone Profile - Capillary Blood Spot test kit consists of blood spot tests for estradiol, progesterone, testosterone, and sex hormone binding globulin (SHBG). The Male Hormone Profile - Capillary Blood Spot test kit consists of blood spot tests for estradiol, testosterone, SHBG, and PSA.

You’re probably wondering, “Why test estradiol, progesterone, and testosterone in blood spot when you already test them in saliva?”

According to Dr. Zava, “Unquestionably, saliva is an excellent means to assess the bioavailable fraction of hormones in the body, and our database clearly shows that salivary hormones are tightly linked with symptoms (e.g., low estradiol is associated with hot flashes, night sweats, vaginal dryness, bone loss, and sleep disturbances). However, in some cases, saliva may not be the appropriate body fluid to measure hormones, and some individuals are just unable to collect saliva due to dry mouth.”

Zava continues, “Listed below are the five principle reasons why we developed the male and female blood spot hormone panels as an alternative to saliva hormone testing:
Using Troches or Sublingual Drops
“The first and foremost reason we developed blood spot hormone panels is to provide a more accurate means to quantify the hormone levels in individuals using hormones as a troche or sublingual [under the tongue] drops. Direct contamination of the oral mucosa [the skin in the mouth] makes it very difficult to accurately measure active, bioavailable hormones in the body for the obvious reason that the oral mucosa and salivary glands become saturated with the supplemented hormone when it is held in the mouth. The extent of local clearing of the supplemented hormone from the oral mucosa varies among individuals, which can, and often does result in high hormone levels in saliva that are not representative of the bioavailable hormone levels throughout the body. At present, the best we can do with saliva is to recommend that at least 36 hours elapse from last use of hormone to testing, but by then the hormone levels have usually cleared to near baseline. The blood spot test measures capillary blood from the finger tip, which is far removed from the oral delivery site and represents hormone delivered to tissues from the bloodstream. At 12-24 hours post hormone supplementation, the blood spot test for estradiol, progesterone, and testosterone provides a far more accurate assessment of hormones being delivered to tissues.

Problems with Producing Saliva (Dry Mouth)
“The second reason we developed the blood spot hormone panel is that some individuals just cannot create enough saliva and suffer from dry mouth (xerostomia). This is particularly problematic as people get older. Many of the prescription drugs taken by the aging population contribute to dry mouth. These include beta-blockers, diuretics, antihistamines, tranquilizers and antidepressants, and painkillers. Dry mouth can also be caused by chemotherapy and radiation treatments. During the course of radiation therapy on the head and neck, the salivary glands are often damaged and destroyed. Some diseases such as Sjögren’s Syndrome, lupus, and diabetes affect the salivary gland’s ability to produce saliva. For these individuals, the blood spot test is more appropriate.

Familiarity with / Preference for Blood Serum Testing
"The third reason is that some individuals would just rather use blood as a testing matrix than saliva because they are not convinced that saliva is a valid method, or are just accustomed to, and more comfortable with, the blood ranges. In individuals not using topical [through the skin] hormones, the conventional serum venipuncture hormone levels are near identical to blood spot finger-stick values. So, when it comes to quantification of hormones produced in the body, such as from the ovaries, there is no advantage of blood spot testing over conventional serum testing. The advantages to blood spot for testing endogenous hormones are convenience, cost, and timing of collection.

“Hormone levels rise and fall, with higher levels in the morning and lower levels as the day progresses, reaching their lowest point late at night. Ranges for normal levels of serum hormones have been derived from morning blood draws; so, if a patient has blood drawn in the afternoon, then levels might be low or within the lower limits of the established ranges. For a conventional blood draw, the patient has it done at the health care provider’s office usually at the time of their scheduled appointment, or they must drive to a blood draw station in the morning to have blood drawn by a phlebotomist. This is inconvenient and usually requires time off work, particularly if this means driving across town to a blood-collection site. These inconveniences add up to extra costs to the patient and the health care practitioner that are not reflected in the base price of the hormone test. In contrast, the blood spot collection can be done conveniently by the patient in their home at the appropriate time of day.

Using Topical Hormone Supplementation
“A fourth and very important reason to use blood spot testing is that, like saliva, hormones present in the “capillary” blood from the finger are more representative of the hormones being delivered to other tissues of the body. With hormones delivered through the skin (e.g., topical, vaginal, sublingual/troche) as supplements, the capillary blood spot hormone level rises in concert with an increase in salivary hormone levels because this represents hormone delivery to tissues throughout the body. In sharp contrast, blood taken by conventional venipuncture rises very little, not at all, or even decreases in some cases with skin delivery of hormones. This might seem odd, but blood being delivered back to the heart through the veins has already delivered its bioavailable hormone load, and hormones remaining in the bloodstream are tightly bound to serum proteins such as SHBG and albumin. An easy way to conceptualize capillary blood (teaming with bioavailable hormones) versus venus blood (depleted of bioavailable hormones) is to think of the oxygen content of red blood cells in the capillary beds versus the venus blood returning to the heart. Blood being delivered to the tissues through the arteries, arterioles, and finally through the capillary beds of tissues is charged with oxygen that is released into the tissues. Blood traveling back to the heart is depleted of oxygen. In a similar way, hormones delivered through the skin are picked up by red blood cells, and the hormone-laden red blood cells are then transported within seconds throughout the body to capillary beds of all tissues. There the hormones are released. This is why we see high capillary blood levels of hormones in blood spot testing and much less hormone in venipuncture serum.

Measuring SHBG and PSA Provides Information About Overall Hormone Status and Risks
“A fifth reason to use the panel blood spot testing is that by including SHBG (males and females) and PSA (males only), the overall estrogen burden and bioavailability of estradiol and testosterone can be calculated and the risk for prostate problems can be assessed, respectively. For females and males, SHBG provides an index of the overall estrogen burden. SHBG is elevated when the estrogen burden in the body is high. SHBG is particularly high in women using contraceptive synthetic steroids (e.g., ethinyl estradiol, norethindorone) who otherwise have very low serum, blood spot, and saliva levels of estradiol, progesterone, and testosterone. The estrogens that induce the liver to manufacture high levels of SHBG can come from a variety of sources including natural, bioidentical estrogens (e.g., estradiol, estrone, estriol), synthetic estrogens used in contraceptives (e.g., ethinyl estradiol), phytoestrogens found in soy or taken as supplements (e.g., genistein, daidzein), and xenoestrogens found in our foods, cosmetics, beverages, and in our environment (e.g., phthalates and pesticides). So, although the levels of estradiol itself may be suppressed by synthetic steroids, the overall estrogen burden to the body could be quite high, as reflected in the SHBG. In males, the SHBG is equally important for assessing the overall estrogenic impact, particularly in men using androgen replacement therapy (testosterone or DHEA) that may convert excessively to estrogens when the aromatase enzyme is high. SHBG binds to both estradiol and testosterone, but binds to testosterone with much greater affinity, which significantly decreases the relative bioavailability of testosterone. This relative increase in estradiol caused by increased SHBG results in feminizing effects in males, which include excessive weight gain in the breasts and hips as well as swelling of the prostate (BPH-benign prostatic hypertrophy). Thus, measurement of SHBG provides a good index of overall estrogen exposure and bioavailable fraction of testosterone.

In summary, the five reasons for developing the female and male blood spot profiles include:

1. Better and more accurate method than saliva to detect bioavailable hormones in individuals using hormonal troches or sublingual drops.

2. Good alternative for individuals who have a dry mouth and cannot produce enough saliva over a reasonable time frame (30 minutes).

3. Individual preference for and familiarity with blood serum testing and blood ranges.

4. Better method than serum venipuncture to detect bioavailable hormones in individuals using topical hormone supplements.

5. Combination of SHBG (male and female) and PSA (male) provides additional information about the overall estrogen burden, bioavailable fraction of testosterone, menopausal status, and potential for overdosing with estrogen or testosterone therapy.”

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