Tribulus terrestris is an ingredient commonly presented as improving testosterone levels, but has not been found to be more effective than a placebo or possess any testosterone increasing properties. WebMD cautions that it interferes with Lithium and diabetes medications, and in general, not enough is known about tribulus terrestris to recommend a dosage for anyone.
Men can experience a range of symptoms if testosterone decreases more than it should. Low testosterone, or low T, is diagnosed when levels fall below 300 nanograms per deciliter (ng/dL). A normal range is typically 300–1000 ng/dL, according to the U.S. Food and Drug Administration. A blood test called a serum testosterone test is used to determine your level of circulating testosterone.
Lets touch on these individually. Gluten has been shown to increase prolactin levels in male mice (48 & 49). Increased prolactin levels in males leads to all sorts of horrible things: Man Boobs (50), High inflammation (51), and most importantly, higher prolactin levels have been shown to be testosterone lowering and lead to shrinking of the testicle (52).
A study published in the Journal of Steroid Biochemistry studied the effects of diet on serum sex hormones in healthy men. Results showed that when men decreased their healthy fat intake, serum concentrations of androstenedione, testosterone and free testosterone also decreased. (8) This indicates you can add low testosterone to the list of low-fat diet risks.
Nutritional developers formulated Nugenix® with Testofen®, a key natural ingredient to help boost “free” testosterone along with resistance training. This key ingredient is carefully extracted from the fenugreek plant. A Testofen® study in Irvine, California indicated positive free testosterone-related results. Nugenix also includes L-Citrulline Malate, Tribulus, Zinc, plus Vitamins B6 and B12 to help promote overall health and performance.*
Researchers at Ball State University found that “strength training can induce growth hormone and testosterone release.” (6) Another study from the University of Nebraska Medical Center researched the acute effects of weight lifting on serum testosterone levels. (7) The results concluded that even moderate weight lifting and light weightlifting increased serum testosterone levels in participants.
Your body’s circadian rhythm essentially resets itself every night and releases chemicals like cortisol, which contribute to the overall hormone balance that can prevent low T-levels. I have even heard one endocrinologist claim that one hour of sleep between 10 p.m. and 2 a.m. has the same healing effects on your body as two hours of sleep before or after this timeslot!
A team led by Dr. Joel Finkelstein at Massachusetts General Hospital investigated testosterone and estradiol levels in 400 healthy men, 20 to 50 years of age. To control hormone levels, the researchers first gave the participants injections of a drug that suppressed their normal testosterone and estradiol production. The men were randomly assigned to 5 groups that received different amounts (from 0 to 10 grams) of a topical 1% testosterone gel daily for 16 weeks. Half of the participants were also given a drug to block testosterone from being converted to estradiol.
Since then there have been many publications documenting suppressed testosterone and gonadotropins (Daniell 2006) in men using opioid medications whether these agents were administrated orally (Daniell 2002) or intrathecally (Finch et al 2000). Not only do opioids act centrally by suppressing GnRH, they also act directly on the testes inhibiting the release of testosterone by Leydig cells during stimulation with human chorionic gonadotropin (Purohit et al 1978). Although the large majority of men (and women) receiving opioids do develop hypogonadism, about 15 percent also develop central hypocorticism and 15 percent develop growth hormone deficiency (Abs et al 2000).
So what is this Big T, anyway? Derived from cholesterol, testosterone is a steroid hormone—called an androgen—that causes the development and maintenance of masculine characteristics. It's mainly secreted by the testicles in males, although the adrenal cortex and ovaries in females also secrete testosterone—though only about one-tenth the amount as in healthy males.
Millions of American men use a prescription testosterone gel or injection to restore normal levels of the manly hormone. The ongoing pharmaceutical marketing blitz promises that treating "low T" this way can make men feel more alert, energetic, mentally sharp, and sexually functional. However, legitimate safety concerns linger. For example, some older men on testosterone could face higher cardiac risks.