Men’s Heart Disease Partly Due to Low Estrogen

[Nelson Vergel]

The study was presented at the Endocrine Society's 97th annual meeting this month. In addition to finding that higher levels of testosterone led to lower HDL, and that estrogen didn't affect HDL, Yu's team found that low levels of estrogen led to higher fasting blood sugar levels, worsening insulin resistance and increasing fat in muscles. The latter indicates developing diabetes, a risk factor for heart disease.



“We found that estrogen deficiency worsens glycemic indices in men, inducing higher levels of fasting glucose and worsened insulin resistance,” Yu told DrugDiscovery & Development. “Estrogen deficiency is thought to have a similar effect in women. We found that testosterone, and not estrogen deficiency, negatively regulates HDL in men. In contrast, estrogens are thought to increase HDL levels in women.”
More work needs to be done.
“It is important to evaluate whether other cardiovascular risk factors are similarly regulated by gonadal steroids in men,” Yu concluded. “For example, we plan to study effects of testosterone and estrogen on inflammatory markers as well as hormones related to fat metabolism and cardiovascular function. An improved understanding of these effects may help to explain sex differences in cardiovascular disease.”

http://www.dddmag.com/articles/2015/03/mens-heart-disease-partly-due-low-estrogen

 

[Nelson Vergel]

So you can see how contradictory things are:

Men with Low Testosterone and Higher Estradiol Are More Prone to Heart Attacks
Maybe this is what matters:

Is Testosterone to Estradiol Ratio Important in Men?

 

[Nelson Vergel]

Another study that shows the negative effects of low estradiol

STUDY LOOKING AT THE EFFECT OF ESTRADIOL ON FAT MASS, SEX DRIVE AND ERECTILE FUNCTION


There was a recently published groundbreaking study about the role of estradiol in men. No optimal ranges of estradiol were noted but low levels were associated with increase fat and decrease in sexual desire and erectile function compared to higher levels (the highest average estradiol was 35 pg/ml unfortunately, so no conclusions can be made for levels above this).

Men had their hormones blocked by a gonadotropin releasing hormone antagonist. All of them then received testosterone supplementation with Androgel. Half were also treated with anastrozole to block estradiol conversion from the testosterone. Please refer to attached graphs.

All participants (Cohorts 1 and 2) received goserelin acetate (Zoladex, AstraZeneca), at a dose of 3.6 mg subcutaneously at weeks 0, 4, 8, and 12, to suppress endogenous gonadal steroids (testosterone and estradiol). All participants (Cohort 1 and 2) were then randomly assigned to receive 0 g (placebo), 1.25 g, 2.5 g, 5 g, or 10 g of a topical 1% testosterone gel (AndroGel, Abbott Laboratories) daily for 16 weeks. Participants in cohort 2 also received anastrozole (Arimidex, AstraZeneca) at a dose of 1 mg daily to block the aromatization of testosterone to estrogen. Participants were unaware of the study group assignments.

Findings:

Higher blood levels of testosterone decreased the percentage of body fat (P = 0.001), intra abdominal fat area (P = 0.021), and subcutaneous fat area (P = 0.029), and increased sexual desire (P = 0.045) and erectile function (P = 0.032).

Low blood level of estradiol was associated with significant increases in the percentage of body fat (P<0.001), subcutaneous fat area (P<0.001), and intra abdominal fat area (P = 0.002), and relative less improvement in sexual desire (P<0.001) and erectile function (P = 0.022). These findings provide additional evidence of an independent effect of estradiol on these variables.

"Our finding that estrogens have a fundamental role in the regulation of body fat and sexual function, coupled with evidence from prior studies of the crucial role of estrogen in bone metabolism, indicates that estrogen deficiency is largely responsible for some of the key consequences of male hypogonadism and suggests that measuring estradiol might be helpful in assessing the risk of sexual dysfunction, bone loss, or fat accumulation in men with hypogonadism. For example, in men with serum testosterone levels of 200 to 400 ng per deciliter, sexual desire scores decreased by 13% if estradiol levels were 10 pg per milliliter or more and by 31% if estradiol levels were below 10 pg per milliliter. "

Reference:

Gonadal Steroids and Body Composition, Strength, and Sexual Function in Men
N Engl J Med 2013;369:1011-22.