The effects of testosterone in humans and other vertebrates occur by way of multiple mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Androgens such as testosterone have also been found to bind to and activate membrane androgen receptors.
Dobs and colleagues found that men with an increased body mass index had both reduced testosterone and reduced high density lipoprotein (HDL) levels. Treatment with testosterone increased the levels of HDL (Dobs et al 2001). Rising levels of HDL are not a consistent finding with TRT. More often, however, one finds reduced total cholesterol, low density lipoprotein (LDL) cholesterol and triglyceride levels with TRT (Zgliczynski et al 1996; Whitsel et al 2001).
Why the difference? The discrepancy in findings between these studies is likely due to the initial training status and base testosterone levels of the subjects. While more research is warranted on this ingredient, D-AA is one of several ingredients suggested to be effective in boosting test levels, especially for older men whose natural testosterone levels have declined due to the natural course of aging.
Keep in mind that you can use virtually any type of equipment you want for this – an elliptical machine, a treadmill, swimming, even sprinting outdoors (although you will need to do this very carefully to avoid injury) -- as long as you're pushing yourself as hard as you can for 30 seconds. But do be sure to stretch properly and start slowly to avoid injury. Start with two or three repetitions and work your way up, don't expect to do all eight repetitions the first time you try this, especially if you are out of shape.
The science backs up the soldier’s self discovery, in fact, exposure to radiation (whether it’s from an army radar or the cell phone in your pocket, or the wifi router in your house) has been shown to lower sperm quality, fertility and testosterone. This is true not only for military personnel (88, 89,90) but all males living in a modern world (91).
This content is strictly the opinion of Dr. Josh Axe and is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of medical advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Axe nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.
The finding of hypogonadism in diabetic men is not just a scientific curiosity, it may have practical management implications. Kapoor and colleagues (2006) undertook a placebo-controlled double blind study to determine the effect of testosterone therapy on insulin resistance and glycemic control in hypogonadal men with type 2 diabetes. They found that men treated with testosterone had reductions in glycated hemoglobin insulin resistance, fasting blood sugar, waist circumference, waist/hip ratio and total cholesterol.
There are several supplements on the market claiming to be natural testosterone boosters. I get these sorts of things in the mail all time. The companies that produce these products claim that the herbs (typically stinging nettle and tribulus) in their pills increase free testosterone by reducing SHBG. They also throw in some B vitamins for “increased energy and vitality.”
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.
With the decline of ovarian function in menopause, not only do estrogen levels decline, but so does testosterone availability, since the ovaries contribute, either by direct secretion or through precursor production, about 50 percent of circulating testosterone. The other 50 percent is supplied by the adrenal glands. Many post-menopausal or oophorectomized women are symptomatic as a consequence of reduced testosterone, the leading symptom being loss of libido (Sherwin and Gelfand 1987; Simon et al 2005). There is an increasing trend toward testosterone supplementation in these women. Such supplementation may also lead, not only to increased libido, but to increased bone mineral density and an improvement in general overall sense of well-being including energy, strength, motivation and mood (Davis et al 1995; Davis et al 2000).
The steroid hormone known as dehydroepiandrosterone, DHEA, plays an important role in sexual behavior, mental health and muscle growth. Your body uses this hormone to make sex steroids. Thus, taking a DHEA supplement should increase your circulating testosterone. A 2018 paper in the International Journal of Sports Medicine explored this possibility in athletic women.
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.
Remember that each person is unique, and each body responds differently to treatment. TT may help erectile function, low sex drive, bone marrow density, anemia, lean body mass, and/or symptoms of depression. However, there is no strong evidence that TT will help memory recall, measures of diabetes, energy, tiredness, lipid profiles, or quality of life.
Every vitamin, mineral, and ingredient that affects the human body can be taken in enough quantities that they are harmful, or toxic, even the ones that — at lower levels — are beneficial or necessary. Unfortunately, testosterone boosters contain a lot of ingredients that are not well understood. This means in addition to not being able to confirm whether certain ingredients increase testosterone, the scientific and medical communities also don’t know at what levels many ingredients become toxic. On the up side, you might need to eat several pounds of a particular leafy plant before it becomes harmful. On the down side, it could be significantly less that pushes you over your body’s limit. We simply don’t know how little or how much the human body can tolerate. We recommend keeping your doctor in the loop when you add any supplement with unproven ingredients into your diet — they’ll be able to help you find and track any undesired side-effects that these ingredients might cause.
Testosterone is necessary for normal sperm development. It activates genes in Sertoli cells, which promote differentiation of spermatogonia. It regulates acute HPA (hypothalamic–pituitary–adrenal axis) response under dominance challenge. Androgen including testosterone enhances muscle growth. Testosterone also regulates the population of thromboxane A2 receptors on megakaryocytes and platelets and hence platelet aggregation in humans.
One study found that men who took 3,332 international units (IU) of vitamin D daily for one year significantly increased their testosterone levels. But vitamin D supplements may only work for men who are severely deficient in this specific vitamin. Another study found that men without a vitamin D deficiency had no increase in testosterone levels after taking vitamin D.
Longjack, also known as Tongkat ali and pasak bumi, is a shrub hailing from Southeast Asia purporting to improve libido. It’s gaining traction in the scientific community for potentially increasing testosterone levels, and researchers at South Africa’s University of the Western Cape found that longjack improved testosterone levels and muscular strength in physically active seniors (a population with typically low testosterone).
There have been case reports of development of prostate cancer in patients during treatment with testosterone, including one case series of twenty patients (Gaylis et al 2005). It is not known whether this reflects an increase in incidence, as prostate cancer is very common and because the monitoring for cancer in patients treated with testosterone is greater. Randomized controlled trials of testosterone treatment have found a low incidence of prostate cancer and they do not provide evidence of a link between testosterone treatment and the development of prostate cancer (Rhoden and Morgentaler 2004). More large scale clinical trials of longer durations of testosterone replacement are required to confirm that testosterone treatment does not cause prostate cancer. Overall, it is not known whether testosterone treatment of aging males with hypogonadism increases the risk of prostate cancer, but monitoring for the condition is clearly vital. This should take the form of PSA blood test and rectal examination every three months for the first year of treatment and yearly thereafter (Nieschlag et al 2005). Age adjusted PSA reference ranges should be used to identify men who require further assessment. The concept of PSA velocity is also important and refers to the rate of increase in PSA per year. Patients with abnormal rectal examination suggestive of prostate cancer, PSA above the age specific reference range or a PSA velocity greater than 0.75 ng/ml/yr should be referred to a urologist for consideration of prostate biopsy.
Everyone knows that carbohydrates are extremely important for testosterone production, but instead of reaching for grains during your next meal, stack your plate high with potatoes. Research reveals that grains have inflammatory properties, but the testosterone-friendly starches in potatoes will have the bodybuilder in your life smiling at dinnertime!
Early infancy androgen effects are the least understood. In the first weeks of life for male infants, testosterone levels rise. The levels remain in a pubertal range for a few months, but usually reach the barely detectable levels of childhood by 4–7 months of age. The function of this rise in humans is unknown. It has been theorized that brain masculinization is occurring since no significant changes have been identified in other parts of the body. The male brain is masculinized by the aromatization of testosterone into estrogen, which crosses the blood–brain barrier and enters the male brain, whereas female fetuses have α-fetoprotein, which binds the estrogen so that female brains are not affected.
Sprinting has been shown numerous times that it has positive effects on testosterone levels. One 2011 study (ref 84) looked at weightlifters who performed 4x35m sprints twice a week. In contrast to the control group (who continued lifting but did not sprint), it was found that “After the 4-week training program, total testosterone and the total testosterone/cortisol ratio increased significantly in the (sprinters) EXP group”.
We required all of our testosterone boosters to have magnesium, but gave preference to magnesium aspartate, citrate, lactate, and chloride. These forms have been found to be more easily absorbed than magnesium oxide and sulfate. (On the other hand, it didn’t count if the supplement had magnesium stearate, which is used to make pills not stick together.)