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Reduced free testosterone increases health risks as well as feelings of fatigue

Restore Youthful Free Testosterone

Reduced free testosterone increases health risks as well as feelings of fatigue. In a placebo-controlled human trial, a pomegranate-cacao blend increased critical free testosterone by 48%.

By Michael Downey.

As men age, they frequently experience symptoms including low libido, erectile dysfunction, reduced strength/muscle mass, fatigue, and even depression.1-3

Many of these issues are associated with low testosterone.

With age, testosterone level fall an average rate of about 1%-2% each year.2

But the real problem is lack of testosterone in its free, biologically active form.

In a clinical study, aging men who received a blend of plant-based nutrients increased their free testosterone levels by 48%.4

The benefits included a nearly 25% increase in a measure of strength and a 19% improvement in symptoms like low libido, exhaustion, anxiety, and feeling burned out.4

Dangers of Low Testosterone

Testosterone is a hormone crucial for development of the male reproductive system and impacts many different functions throughout the body. Common low testosterone symptoms include diminished sexual desire, erectile dysfunction, fatigue, reduced muscle mass and strength, and overall loss of youthful well-being.

Testosterone deficiency in men has been correlated with a greater risk of: 5-12

  • Cardiovascular disease,
  • Osteoporosis,
  • Chronic inflammation,
  • Neurodegeneration, including cognitive decline and Alzheimer's disease,
  • Metabolic syndrome and type II diabetes,
  • Prostate cancer,
  • Depression, and
  • All-cause mortality.

Importance of Free Testosterone

Raising free testosterone levels in aging men is critical.

Testosterone circulates in the blood in two forms, bound to sex hormone-binding globulin (SHBG), albumin, and other proteins; and as unbound free testosterone.13

The most biologically active form is free testosterone, and people are often surprised to learn that only 3% of their testosterone is in this bioactive "free" form.14

This leaves about 97% of total testosterone that is not available for the body to use. It is not available to the cells because it is bound to proteins in the blood.

With age, critical free testosterone levels tend to decline.13

Overweight men are at an even higher risk for low testosterone.13 Being overweight or obese is associated with increased levels of the enzyme aromatase, which converts testosterone into estrogen.15,16

Pomegranate and Cacao Boost Testosterone

Seeking a safe and drug-free way to raise testosterone levels, scientists took note of a study presented at an endocrinology conference over a decade ago.

The study found that in healthy adults, intake of pomegranate juice for just two weeks increased salivary testosterone levels by 23%-27%. Measures of mood and well-being also improved.17

These findings inspired researchers to screen hundreds of plant extracts and nutrients for their ability to raise testosterone levels.

In a study using testes cells from mice, researchers confirmed that pomegranate extract raised testosterone production.18

In the same study, they discovered that an extract of cacao seed, from the beans used to make cocoa and chocolate, also significantly increased testosterone production.18

Researchers then combined pomegranate and cacao seed extracts and found that together, they boosted total testosterone levels in rats by over 72% in just six weeks.19,20

What You Need to Know

Boost Testosterone for Better Health

  • Around age 30, testosterone levels in men begin to drop steadily, especially biologically active free testosterone.
  • Low testosterone is associated with erectile dysfunction, virility loss, fatigue, low strength, and serious health issues including heart disease, diabetes, cognitive decline, and all-cause mortality.
  • In a human trial, a blend of pomegranate and cacao seed extracts increased free testosterone by 48% and led to increased strength, reduced stress, and improvements in symptoms like low libido, exhaustion, and depression.
  • Preclinical studies show that the flavonoid luteolin may also support testosterone production and prevent its conversion into estrogen.
  • Combining luteolin with pomegranate and cacao extracts may help men maintain healthy, youthful free testosterone levels at any age.

Human Trials

To evaluate pomegranate and cacao extracts in humans, researchers gave men aged 36 to 55 either a blend of these extracts or a placebo.

After eight weeks, levels of free testosterone in men receiving 400 mg of the pomegranate-cacao blend were elevated by over 48% compared to baseline.4

In addition, in men taking the pomegranate-cacao blend:4

  • Overall well-being improved,
  • Measures of stress dropped by 26%, and
  • Hand grip strength increased by almost 25%.

The pomegranate-cacao group also reduced their symptoms on the Aging Males' Symptoms scale by 19%.4 These symptoms include:21

  • Joint pain and muscle aches,
  • Excessive sweating,
  • Sleep problems and exhaustion,
  • Anxiety and irritability,
  • Depression and feeling burned out,
  • Decrease in libido, and
  • Other sexual problems.

Raising testosterone in younger men is more challenging, because their levels have not yet dropped as much.

Surprisingly, even in men aged 21 to 35, in a separate trial, a pomegranate-cacao blend increased free testosterone by 25%. After four weeks of supplementation, hand grip strength and the circumference of the upper arm significantly increased as well.19

Luteolin Supports Testosterone Production

Preclinical studies have shown that a third ingredient can support healthy testosterone levels.

Luteolin is a flavonoid found in certain plants, including celery, broccoli, parsley, and thyme.

Cell and animal studies show that luteolin may support healthy testosterone levels by:

  • Increasing steroidogenic acute regulatory (StAR) protein, an enzyme required for testosterone production,22 and
  • Inhibiting aromatase, the enzyme that converts testosterone into estrogen.23-25

A combination of pomegranate, cacao, and luteolin may maximize support for healthy free testosterone levels in men.

Optimum Testosterone Levels

The best way to check free and total testosterone levels is with simple blood tests.

In men, the optimal ranges for testosterone in the blood are:

  • Free testosterone: 15-25 pg/mL.
  • Total testosterone: 600-900 ng/dL.


Around age 30, testosterone levels in men begin to decline. Critical free testosterone levels drop.

Low testosterone is associated with loss of energy and strength, low libido, erectile dysfunction, increased risk for heart disease, diabetes, cognitive decline, and death from any cause.

In a clinical study, pomegranate and cacao seed extracts increased free testosterone by 48%, reduced stress, boosted strength, and improved symptoms like low libido and exhaustion.

Preclinical studies suggest that the flavonoid luteolin also supports youthful testosterone levels.

Together, these ingredients may help men boost free testosterone, maintaining healthy vigor while helping to prevent serious disorders.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.


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