Metabolic Health

Free Androgen Index

Optimal Result: 0 - 6.6 u.

The free androgen index is a measure of the biologically active testosterone in the blood. It is a ratio of the total testosterone to the level of sex hormone-binding globulin (SHBG). About half of all testosterone in the blood is tightly bound to SHBG and the rest is either free or loosely bound to albumin. Only the portion that is free or bound to albumin is considered biologically active. The portion bound to SHBG is considered biologically inert. Thus, by calculating the ratio of total testosterone to SHBG, one can get a measurement of physiologically active testosterone in the blood. The free androgen index is expressed in the same units and multiplied by 100 to provide a number similar to the free testosterone concentration in blood. Normal free androgen index results are slightly higher than free testosterone levels, however. As a ratio, there are no units. The free androgen index may be a more accurate assessment of free testosterone in women than in men.

Normal Ranges for Free Androgen Index:

• Male:

− 20 to 29 years: 30.0−128.0

− 30 to 39 years: 24.0−122.0

− 40 to 49 years: 14.0−126.0

− Older than 49 years: 18.0−82.0

• Female:

− 20 to 49 years: 0.4−8.4

− Older than 49 years: 0.4−6.6

 

Sources:

https://www.labcorp.com/test-menu/25691/free-androgen-index-fai

https://www.labcorp.com/test-menu/35496/testosterone-free-direct

https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=167&ContentID=free_androgen_index

https://www.webmd.com/men/features/low-testosterone-explained-how-do-you-know-when-levels-are-too-low#1

https://www.uptodate.com/contents/overview-of-androgen-deficiency-and-therapy-in-women

What does it mean if your Free Androgen Index result is too low?

Adult men with too little testosterone may lose lean muscle mass, become fatigued, feel weak, and develop depression. Low testosterone can reduce libido and contribute to erectile dysfunction. Gynecomastia—the development of breast tissue in men—is another symptom of low testosterone. Boys with low testosterone may fail to develop secondary sex characteristics such as deepened voice, pubic hair, and facial hair. Low testosterone is less problematic for women, but it can interfere with sexual function.

Some specific causes of low free androgen index are:

- Hypogonadism

- Testicular injury

- Testicular cancer

- Testicular cancer treatment

- Type 2 diabetes mellitus

- Obesity

- Chronic liver disease

- Chronic kidney disease

What does it mean if your Free Androgen Index result is too high?

A high free androgen index value indicates that there is too much biologically active testosterone in the blood. Men with too much testosterone may be overly aggressive, develop cystic acne, and have increased body hair. In general, however, adult men may not notice symptoms of too much testosterone. Women with high testosterone develop many noticeable symptoms and signs such as unusual hair growth, obesity, hoarseness, and menstrual irregularities. Children with high testosterone may develop precocious puberty. 

Some specific causes of high free androgen index are:

- Polycystic ovarian syndrome

- Testosterone-secreting tumor

10 000+ happy clients
100% satisfaction
★ ★ ★ ★ ★ customer support

Understand blood, stool, and urine medical results from all your laboratories.

Get Started With Our Personal Plan

Advanced Plan

  • ✓ Yearly subscription
  • ✓ Five free uploads
  • ✓ Cancel anytime
  • ✓ Instant interpretations
  • ✓ Use the free self-upload form
  • ✓ 3000+ biomarkers explained
  • ✓ Nutrition Recommendations
  • ✓ Dedicated support
  • ✓ Yearly subscription
  • ✓ Five free uploads
  • ✓ Cancel anytime
$79 per year
  • ✓ Instant interpretations
  • ✓ Use the free self-upload form
  • ✓ 3000+ biomarkers explained
  • ✓ Nutrition Recommendations
  • ✓ Dedicated support

Unlimited Plan

  • ✓ No subscription
  • ✓ Ten free uploads
  • ✓ Unlimited access
  • ✓ Instant interpretations
  • ✓ Use the free self-upload form
  • ✓ 3000+ biomarkers explained
  • ✓ Nutrition Recommendations
  • ✓ Dedicated support
  • ✓ No subscription
  • ✓ Ten free uploads
  • ✓ Unlimited access
$250 full version

Are You a Health Professional?

Get started with our professional plan

Welcome to Healthmatters Pro.

Save time on interpreting lab results with the largest database of biomarkers online. In-depth research on any test at your fingertips, all stored and tracked in one place. Learn more

Pro Plan

for health professionals

  • ✓ Track multiple clients results
  • ✓ No setup fees
  • ✓ No hidden costs
  • ✓ Cancel anytime
  • ✓ Instant interpretations
  • ✓ Use the free template forms
  • ✓ 3000+ biomarkers explained
  • ✓ Additional team member $25
  • ✓ Personal training and support

$45 per month

Use promo code to save 10% off any plan.


We implement proven measures to keep your data safe.

At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put industry-leading security standards in place to help protect against the loss, misuse, or alteration of the information under our control. We use procedural, physical, and electronic security methods designed to prevent unauthorized people from getting access to this information. Our internal code of conduct adds additional privacy protection. All data is backed up multiple times a day and encrypted using SSL certificates. See our Privacy Policy for more details.

×

Understand Your Lab Result Now

  • Instant interpretation
  • 3000+ biomarkers explained
  • Science-based recommendations
  • Online support
  • Secure and private portal

Get 10% off with promocode: