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Testosterone deficiency, or low T, negatively affects a man’s quality of life and is a known risk factor for early death. Testosterone levels are at their highest by early adulthood and then decrease by 1–2 percent each year around age 40.
Why is low T harmful? Testosterone has effects on the brain, skin, bones, and heart, and impacts erectile function, fat metabolism, muscle growth, bone density, energy production, lipid levels, insulin balance, and much more.
The Most Common Cause of Low T
Primary hypogonadism, which occurs when the testicles don’t produce enough testosterone, is the leading contributor to low testosterone. This may be spurred by certain endocrine-disrupting chemicals that find their way into the body through water bottles, and other plastics, cosmetics, canned food, fertilizers, toothpaste, clothes, soaps, paper, textiles, carpets, utensils, deodorants, bedding, and other commonly used products.
The Best Way to Get Tested
The primary test for testosterone deficiency is total testosterone. Unfortunately, there isn’t a consensus as to what precise range indicates a deficient blood level of total testosterone. Laboratories differ in their testosterone reference ranges, although they normally range from 250 ng/dL to 400 ng/dL and up to 1000 to 1100 ng/dL. The American Urological Association states that a total testosterone level below 300 ng/dL is a reasonable cutoff for healthy testosterone.
Testosterone deficiency should be diagnosed with two separate total testosterone measurements in the early morning because levels vary significantly due to normal hormonal rhythms of the endocrine system and are highest in the early morning.
Foods That Boost Testosterone
A study in the journal Nutrients demonstrated that the Standard American Diet (SAD) is significantly associated with low total testosterone levels and an unhealthy body composition (decreased skeletal muscle mass and increased visceral fat mass). Specifically, this study found that dietary patterns “characterized by high-frequency consumption of bread and pastries, dairy products, and desserts; eating out; and low intake of homemade foods, noodles, and dark green vegetables” were significantly associated with low testosterone. A modified Mediterranean diet is a good choice for men with low T. Think vegetables, fruits, seafood, poultry, beans, herbs and spices, olive oil, nuts, moderate dairy, and limited red meat.
The Right Exercise
Resistance training is typically recommended for improving testosterone levels in men. However, a study of 87 men with erectile dysfunction who followed aerobic exercise with stationary cycling had a better increase of testosterone than those who performed strengthening exercises. The total amount of exercise may be more important than the type.
Top 2 Herbal Remedies for Low T
Testosterone replacement, usually with topical creams or gels, or through intramuscular injections, is often used as a treatment for men with an overt testosterone deficiency. However, men with mildly low testosterone levels or low-normal levels will usually respond to tried-and-true herbal therapies, especially ashwagandha and Eurycoma longifolia.
Ashwagandha extract has been shown to significantly increase testosterone levels compared to placebo in men. In an 8-week randomized, placebo-controlled, double-blind study, 57 men aged 18–50 with little experience in resistance training were given ashwagandha extract (300 mg) or a placebo twice daily. Baseline measurements were taken, and then the men followed a resistance training program. Their measurements were retaken at the end of the eight weeks.
Researchers found the men taking ashwagandha extract had significantly increased testosterone levels (96.19 ng/dL) compared to those taking a placebo (18.0 ng/dL). The men taking ashwagandha extract also had a significantly greater increase in muscle strength as measured with bench press and leg extension exercises, increased muscle size of the arms and chest, greater decreases in body fat percentage (3.5 percent compared to 1.5 percent for placebo), and decreased exercise-induced muscle damage (as measured by serum creatine kinase level). None of the participants experienced adverse effects.
Another study, published in Evidence-Based Complementary and Alternative Medicine, looked at the effect of ashwagandha on hormone levels and the sperm-producing activity of 46 men with low sperm count. The men were randomized to receive ashwagandha extract (675 mg per day) or a placebo. Serum hormone levels (testosterone and LH) were tested at the beginning and end of the 90-day study. Serum testosterone increased by 17 percent and LH (which stimulates testes production of testosterone) increased by 34 percent as compared to baseline. Participants taking a placebo did not have an increase in testosterone levels.
Recommendation: 600–675 mg daily of a standardized extract.
Safety: Ashwagandha is well tolerated.
Eurycoma longifolia (also known as Tongkat Ali, Malaysian Ginseng, and Longjack) has been shown to improve erectile unction, libido, and male sexual well-being, as well as stimulate the synthesis of both total testosterone and free testosterone. In a study from the Journal of the International Society of Sports Nutrition, researchers looked at the effects of 200 mg of Eurycoma longifolia extract on people who were “moderately stressed.” Compared to placebo, those taking the extract had a significant increase in testosterone (37 percent) and a significant decrease in cortisol (16 percent). Furthermore, those taking the extract showed significant improvements in tension, anger, and confusion.
In a five-week study of physically active male and female seniors (ages 57 to 72), supplementation with Eurycoma longifolia extract (400 mg daily) was shown to significantly increase total and free testosterone concentrations and muscular force in men and women. Handgrip strength measures improved as a reflection of an increase in muscle force. No side effects were noted for those supplementing with Eurycoma longifolia extract.
Recommendation: 200–400 mg daily of an extract
Safety: Eurycoma longifolia has been shown in a review of studies to be safe based on no significant changes in liver or kidney function tests.