It is now well-established that elderly men with type 2 diabetes mellitus have reduced levels of testosterone (Barrett-Connor 1992; Betancourt-Albrecht and Cunningham 2003). It is known, however, that obese men and diabetic men have reduced levels of SHBG (Barrett-Connor 1990) which could account for the lower total testosterone levels found in diabetic men. Dhindsa et al (2004) studied 103 male patients who had type 2 diabetes mellitus using free testosterone (done by equilibrium dialysis) or calculated free testosterone which takes SHBG levels into account. Of the 103 patients, 57 had free testosterone by equilibrium dialysis and of these, 14 (25%) had a free T below 0.174 nmol/L and were considered hypogonadal. Using a total testosterone of 10.4 nmol/L (300ng/dl) as the lower limit of normal 45 patients (43%) were in the hypogonadal range. They also found that LH and FSH concentrations were significantly lower in the hypogonadal group. The authors thus concluded that hypogonadotropic hypogonadism was a common finding in type 2 diabetes irrespective of glycemic control, duration of disease or the presence of complications of diabetes or obesity.
Findings that improvements in serum glucose, serum insulin, insulin resistance or glycemic control, in men treated with testosterone are accompanied by reduced measures of central obesity, are in line with other studies showing a specific effect of testosterone in reducing central or visceral obesity (Rebuffe-Scrive et al 1991; Marin, Holmang et al 1992). Furthermore, studies that have shown neutral effects of testosterone on glucose metabolism have not measured (Corrales et al 2004), or shown neutral effects (Lee et al 2005) (Tripathy et al 1998; Bhasin et al 2005) on central obesity. Given the known association of visceral obesity with insulin resistance, it is possible that testosterone treatment of hypogonadal men acts to improve insulin resistance and diabetes through an effect in reducing central obesity. This effect can be explained by the action of testosterone in inhibiting lipoprotein lipase and thereby reducing triglyceride uptake into adipocytes (Sorva et al 1988), an action which seems to occur preferentially in visceral fat (Marin et al 1995; Marin et al 1996). Visceral fat is thought to be more responsive to hormonal changes due to a greater concentration of androgen receptors and increased vascularity compared with subcutaneous fat (Bjorntorp 1996). Further explanation of the links between hypogonadism and obesity is offered by the hypogonadal-obesity-adipocytokine cycle hypothesis (see Figure 1). In this model, increases in body fat lead to increases in aromatase levels, in addition to insulin resistance, adverse lipid profiles and increased leptin levels. Increased action of aromatase in metabolizing testosterone to estrogen, reduces testosterone levels which induces further accumulation of visceral fat. Higher leptin levels and possibly other factors, act at the pituitary to suppress gonadotrophin release and exacerbate hypogonadism (Cohen 1999; Kapoor et al 2005). Leptin has also been shown to reduce testosterone secretion from rodent testes in vitro (Tena-Sempere et al 1999). A full review of the relationship between testosterone, insulin resistance and diabetes can be found elsewhere (Kapoor et al 2005; Jones 2007).
Nearly 1 out of every 4 men over age 50 experience the pain of losing the ability to perform sexually as a result of erectile dysfunction (ED). Common causes of ED are atherosclerosis, diabetes, prescription drug use (namely high blood pressure, depression, and allergy drugs), and—you guessed it—low testosterone. Supplements that may help include the following:
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.
Testosterone is a hormone with multifaceted physiological functions and multiple associations with pathophysiological states. It is an important hormone in male reproductive and metabolic function from intrauterine life to old age. In severe or classical hypogonadal states there is little controversy about the need to administer testosterone by an intramuscular, oral or transdermal formulation. There is controversy about making the diagnosis in the less severe cases of hypogonadism associated with the aging male but the current evidence suggests that this is efficacious in appropriately selected men and that there is little if any risk in giving aging symptomatic hypogonadal men a 6 month trial of therapy to determine whether symptoms will improve.
According to the Mayo Clinic, testosterone therapy can help treat hypogonadism. This condition occurs when the body can’t produce enough testosterone on its own. However, it’s unclear whether supplements can help. A study published in found no scientific reason to prescribe testosterone to men over 65 years of age with normal or low to normal testosterone levels.
In accordance with sperm competition theory, testosterone levels are shown to increase as a response to previously neutral stimuli when conditioned to become sexual in male rats. This reaction engages penile reflexes (such as erection and ejaculation) that aid in sperm competition when more than one male is present in mating encounters, allowing for more production of successful sperm and a higher chance of reproduction.
Testosterone is a steroid sex hormone found in both men and women. In men, testosterone is produced primarily by the Leydig (interstitial) cells of the testes when stimulated by luteinizing hormone (LH). It functions to stimulate spermatogenesis, promote physical and functional maturation of spermatozoa, maintain accessory organs of the male reproductive tract, support development of secondary sexual characteristics, stimulate growth and metabolism throughout the body and influence brain development by stimulating sexual behaviors and sexual drive. In women, testosterone is produced by the ovaries (25%), adrenals (25%) and via peripheral conversion from androstenedione (50%). Testerone in women functions to maintain libido and general wellbeing. Testosterone exerts a negative feedback mechanism on pituitary release of LH and follicle-stimulating hormone (FSH). Testosterone may be further converted to dihydrotestosterone or estradiol depending on the tissue.
Meat. Meat, particularly beef, provides our bodies with the protein it needs to create muscle (more muscle = more T) and the fats and cholesterol to make testosterone. My meat topping of choice was sliced up chuck steak. I grilled two of them on Monday and it lasted me until the next Monday. Every now and then I’d slow-cook some ribs or brisket to use as my meat topping. My philosophy was the fattier, the better.
When testosterone and endorphins in ejaculated semen meet the cervical wall after sexual intercourse, females receive a spike in testosterone, endorphin, and oxytocin levels, and males after orgasm during copulation experience an increase in endorphins and a marked increase in oxytocin levels. This adds to the hospitable physiological environment in the female internal reproductive tract for conceiving, and later for nurturing the conceptus in the pre-embryonic stages, and stimulates feelings of love, desire, and paternal care in the male (this is the only time male oxytocin levels rival a female's).
This supplement contains herbal remedies to enhance the male hormone and increase a man's sexual desire. Ingredients found in the product include horney goat weed, milk thistle, tribulis terristris, wild yam, saw palmetto and maca. The manufacturer of the supplement claims that it is endorsed by a doctor for male enhancement. Recommended dosage is one capsule taken before engaging in sexual activity. Women should not take a testosterone supplement unless otherwise advised by a physician.
Although some men believe that taking testosterone medications may help them feel younger and more vigorous as they age, few rigorous studies have examined testosterone therapy in men who have healthy testosterone levels. And some small studies have revealed mixed results. For example, in one study healthy men who took testosterone medications increased muscle mass but didn't gain strength.