74 replies to this topic

[misterE]

Have you ever heard that vegetarians or vegans have low testosterone levels? I can’t count how many times people have said to me that animal-protein and saturated-fat is crucial for testosterone production. However when you look at the research, the facts are quite different.

In 1987, a study by Dr. William Rosner looked at the levels of testosterone and sex-hormone-binding-globulin (SHBG; testosterones transport-protein) on two different diets with the same net calories. One diet was high in meat, the other was high in whole-grains. He found that testosterone levels were 23% higher in the subjects eating whole-grains compared to the subjects eating meat. SHBG levels were also 33% higher in the subjects eating whole-grains compared to the subjects eating meat [1].

A 1990 study done in England found that vegans had 7% higher testosterone and 23% higher SHBG than omnivores [2]. A study done ten years later, also in England, looked at hormone levels in vegan, vegetarian, and meat-eating men and found that testosterone and SHBG levels were about 15% higher in vegan men compared to meat-eaters. The vegan men had about 10% higher levels than vegetarians [3].

So why do we hear all the time that vegans have low testosterone? Many lay people argue that since it is well known that a vegan diet will increase SHBG, that this will inevitably bind up all your free-testosterone and render it useless, they suggest eating meat to lower SHBG and thus “free-up” this bound-testosterone. What these lay people don’t understand is that SHBG is positively correlated with testosterone [4-5].

Levels of both testosterone and SHBG have drastically declined in industrial-societies since the 1920’s [6-7]. The cause of this is thought to be caused by the metabolic-syndrome, a disease like state that causes low SHBG and testosterone [8-10]. Fortunately people following plant-based diets don’t have metabolic-syndrome [11-12].






[1] Life Sci. 1987 May 4;40(18):1761-8. Diet-hormone interactions: protein/carbohydrate ratio alters reciprocally the plasma levels of testosterone and cortisol and their respective binding globulins in man. Anderson KE, Rosner W, Khan MS.

[2] Br J Nutr. 1990 Jul;64(1):111-9.Testosterone, sex hormone-binding globulin, calculated free testosterone, and oestradiol in male vegans and omnivores. Key TJ, Roe L, Thorogood M.

[3] Br J Cancer. 2000 Jul;83(1):95-7. Hormones and diet: low insulin-like growth factor-I but normal bioavailable androgens in vegan men. Allen NE, Appleby PN, Davey GK.

[4] J Clin Endocrinol Metab. 2005 Jan;90(1):157-62. Associations of sex-hormone-binding globulin (SHBG) with non-SHBG-bound levels of testosterone and estradiol in independently living men. de Ronde W, van der Schouw YT, Muller M.

[5] Clin Endocrinol (Oxf). 2005 Apr;62(4):498-503. Serum levels of sex hormone-binding globulin (SHBG) are not associated with lower levels of non-SHBG-bound testosterone in male newborns and healthy adult men. de Ronde W, van der Schouw YT, Pierik FH.

[6] J Clin Endocrinol Metab. 2007 Dec;92(12):4696-705. Secular decline in male testosterone and sex hormone binding globulin serum levels in Danish population surveys. Andersson AM, Jensen TK, Juul A.

[7] J Clin Endocrinol Metab. 2007 Jan;92(1):196-202. Epub 2006 Oct 24. A population-level decline in serum testosterone levels in American men. Travison TG, Araujo AB, O'Donnell AB.

[8] Diabetes Care. 2004 May;27(5):1036-41. Testosterone and sex hormone-binding globulin predict the metabolic syndrome and diabetes in middle-aged men. Laaksonen DE, Niskanen L, Punnonen K.

[9] Eur J Endocrinol. 2008 Jun;158(6):785-92. Lower sex hormone-binding globulin is more strongly associated with metabolic syndrome than lower total testosterone in older men: the Health in Men Study. Chubb SA, Hyde Z, Almeida OP.

[10] Diabetes Care. 2010 Jul;33(7):1618-24. Association of testosterone and sex hormone-binding globulin with metabolic syndrome and insulin resistance in men. Li C, Ford ES, Li B.

[11] Eur J Nutr. 2006 Feb;45(1):52-4. No evidence of insulin resistance in normal weight vegetarians. A case control study. Valachovicová M, Krajcovicová-Kudlácková M, Blazícek P.

[12] Br J Nutr. 2006 Jan;95(1):129-35. Taiwanese vegetarians have higher insulin sensitivity than omnivores. Hung CJ, Huang PC, Li YH.

[Hebbeh]

You are misinterpreting the results. You don't want high SHBG. Bound Testosterone isn't doing anything productive. Free Testosterone is what is active in the body. The results indicate that the net free T would be lower in the veg diet. No thanks.

edit: and SHBG doesn't transport T...just like it says, it BINDS T so that it can't be used by the body. SHBG keeps T from getting too high...but if you have high levels of SHBG, it will depress the bioactive free T. Ask any athlete.

Edited by Hebbeh, 12 July 2012 - 03:04 AM.

[misterE]

You are misinterpreting the results. You don't want high SHBG. Bound Testosterone isn't doing anything productive. Free Testosterone is what is active in the body. The results indicate that the net free T would be lower in the veg diet. No thanks.

edit: and SHBG doesn't transport T...just like it says, it BINDS T so that it can't be used by the body.

I take it you are not familar with the SHBG-receptor (SHBGR)? Or the fact that obesity, diabetes, and heart-disease is correlated with low SHBG levels? Read studies 8-10.

Edited by misterE, 12 July 2012 - 03:07 AM.

[Hebbeh]

You are misinterpreting the results. You don't want high SHBG. Bound Testosterone isn't doing anything productive. Free Testosterone is what is active in the body. The results indicate that the net free T would be lower in the veg diet. No thanks.

edit: and SHBG doesn't transport T...just like it says, it BINDS T so that it can't be used by the body.

I take it you are not familar with the SHBG-receptor (SHBGR)? Or the fact that obesity, diabetes, and heart-disease is correlated with low SHBG levels?

I used to do amateur Bodybuilding and am very familiar. And am still very fit at 55. Your information is wrong.

[misterE]

I used to do amateur Bodybuilding and am very familiar. And am still very fit at 55. Your information is wrong.

That's all you can say? How do you debunk the studies I posted? What about the SHBG-receptor?

[Hebbeh]

I used to do amateur Bodybuilding and am very familiar. And am still very fit at 55. Your information is wrong.

That's all you can say? How do you debunk the studies I posted? What about the SHBG-receptor?

Here you go...short and sweet:
http://en.wikipedia....inding_globulin

Your studies are the typical chicken or egg....SHBG is low because hormones are low because your endocrine system is messed up probably from unhealthy lifestyle which ALL leads to metabolic syndrome.

[Brafarality]

Subjective and Anecdotal:
I have nothing to add from a scientific vantage but can only say that I have been a vegetarian since 1987 and a vegan since 1995 and I have a pretty (no, very) low sex drive. It is one of the less than appealing effects of the diet, imho. Thus, when I am charged with a raw sexual desire, I relish it more. Maybe the scarcity has made me more appreciative.
But, from a purely personal and anecdotal viewpoint, I definitely believe I am not surging in testosterone, certainly not more than the average person. Want to change that one day. Sexual desire and arousal is a good thing. Know I am missing out on some aspect of life, so will maybe change sooner rather than later.
BTW: Assuming a correlation between testosterone levels and sex drive. Know there are many exceptions to this, but it generally holds.

Edited by Brafarality, 12 July 2012 - 06:02 AM.

[PeopleOverCorporateProfit]

The boxer who just beat Manny Paquio is a vegan. Did he deserve to win? No. Is he ripped and an amazing athlete? Yes.

[PeopleOverCorporateProfit]

Also, Tony Gonzalez eats a mostly vegan diet. Arian Foster recently went vegan. If you don't know them, they are NFL superstars.

[sthira]

Outcome (haha) depends upon one person's unique vegan diet upon one person's unique biology, lifestyle, and what's hidden. So much of chemistry is mysterious -- and all is flux.

[misterE]

Your studies are the typical chicken or egg....SHBG is low because hormones are low because your endocrine system is messed up probably from unhealthy lifestyle which ALL leads to metabolic syndrome.

What about the two studies I posted (# 4 and 5) showing that SHBG is positively associated with both total and free-testosterone? Plus, you have not answered my question about the SHBG-receptor or shown any studies to back up your argument... wikipedia doesn't count. Perhaps you can direct me to some studies indicating that low SHBG is healthier in terms of metabolic-syndrome, so far the bulk of the scientific-literature shows the exact opposite!

Take a look at the diagram below, this is taken from reference #4, it clearly shows that SHBG is positively correlated with total-testosterone and to a lesser extent free-testosterone.

Edited by misterE, 12 July 2012 - 10:11 PM.

[Luminosity]

There are plenty of vegans and vegetarians where I live. In general they would seem to have lower testosterone, especially vegans. There are exceptions. There are some outdoorsy types who surf and seem highly testosteronized even though they are vegan/vegetarian. If you eat a lot of commericial animal products you can also pick up a lot of synthetic estrogen which was fed to the animals, which will not help. That also depends on the person. Some people develop sloth and man-boobs from stuff like that, others don't. Commercial chicken and eggs are the worst for that, followed by commercial dairy.

You need to listen to your body.

Edited by Luminosity, 13 July 2012 - 01:54 AM.

[misterE]

Since SHBG inhibits the metabolic-clearance-rate (MCR) of testosterone [1], anything that decreases SHBG, will increase the rate in which testosterone is cleared from the body, thus lowering the total amount. The rich western-diet (high in animal-based and processed foods) causes low SHBG [2], thus low testosterone. I believe this is the main mechanism on how the rich western-diet causes testosterone-deficiency and hyperestrogenemia [3]. Secondary factors are probably the estrogen located in dairy-products [4-6], the dioxins found in animal-fats [7] and excess aromatase activity induced by obesity [1].



[1] Cancer Res. 1982 Aug;42(8 Suppl):3281s-3285s. Obesity, androgens, estrogens, and cancer risk. Kirschner MA, Schneider G, Ertel NH.

[2] Scand J Clin Lab Invest Suppl. 1990;201:3-23. Western diet and Western diseases: some hormonal and biochemical mechanisms and associations. Adlercreutz H.

[3] Am J Med. 1985 Mar;78(3):363-6. Hyperestrogenemia, diet, and disorders of Western societies. Phillips GB.

[4] J Dairy Sci. 2010 Jun;93(6):2533-40. Estrone and 17beta-estradiol concentrations in pasteurized-homogenized milk and commercial dairy products. Pape-Zambito DA, Roberts RF, Kensinger RS.

[5] J Dairy Sci. 2012 Apr;95(4):1699-708. Comparison of estrone and 17β-estradiol levels in commercial goat and cow milk. Farlow DW, Xu X, Veenstra TD.

[6] Pediatr Int. 2010 Feb;52(1):33-8. Exposure to exogenous estrogen through intake of commercial milk produced from pregnant cows. Maruyama K, Oshima T, Ohyama K.

[7] http://www.epa.gov/p...ubs/dioxins.htm

[hivemind]

There are different vegan diets. I think it's more about the amount of fat than it is about being a vegan. A vegan can have a high fat diet. Low fat diets reduce testosterone.

[Luminosity]

Yeah, a low fat/oil diet would be bad for hormone production. But you need to eat healthy fats. And a little bit of sun plus vitamin D and maybe K will help your body make the right hormones.

[niner]

Your studies are the typical chicken or egg....SHBG is low because hormones are low because your endocrine system is messed up probably from unhealthy lifestyle which ALL leads to metabolic syndrome.

What about the two studies I posted (# 4 and 5) showing that SHBG is positively associated with both total and free-testosterone? Plus, you have not answered my question about the SHBG-receptor or shown any studies to back up your argument... wikipedia doesn't count. Perhaps you can direct me to some studies indicating that low SHBG is healthier in terms of metabolic-syndrome, so far the bulk of the scientific-literature shows the exact opposite!

Take a look at the diagram below, this is taken from reference #4, it clearly shows that SHBG is positively correlated with total-testosterone and to a lesser extent free-testosterone.

I don't think these graphs show anything. The first, between total T and SHBG isn't much of a correlation, and what correlation there is could be attributed to the fact that the more SHBG you have, the more T it can soak up. The second graph, which is more or less a graph of free T vs SHBG, looks like a 'correlation' of almost exactly zero. What's the SHBG receptor and how does it fit into your argument?

If a Wikipedia article is referenced decently, you can't just say it "doesn't count". It's usually pretty reliable for basic scientific information.

[hivemind]

You don't need a high fat diet however for hormone production. You just have to eat enough fat and not limit it too aggressively.

[misterE]

There are different vegan diets. I think it's more about the amount of fat than it is about being a vegan. A vegan can have a high fat diet. Low fat diets reduce testosterone.

This might be true (to a small extent), but what really matters is the testosterone to estrogen ratio. A study using the Pritikin-diet, showed that men eating a very low-fat (10%), high-fiber diet based on whole-grains, reduced their estrogen levels by 50% and testosterone levels did not change, thus they experienced an increase in their testosterone to estrogen ratio [1]. The same was found with women [2].

High-fat diets are known to increase estrogen levels.


[1] Am J Med. 1985 Jan;78(1):23-7. Effects of a high-complex-carbohydrate, low-fat, low-cholesterol diet on levels of serum lipids and estradiol. Rosenthal MB, Barnard RJ, Rose DP.

[2] Nutrition. 1991 Mar-Apr;7(2):137-9. Reduction of serum estradiol in postmenopausal women given free access to low-fat high-carbohydrate diet. Heber D, Ashley JM, Leaf DA

[misterE]

But you need to eat healthy fats.

The only fats you need to eat are the essential-fatty-acids (omega-3 and omega-6).

[hivemind]

But you need to eat healthy fats.

The only fats you need to eat are the essential-fatty-acids (omega-3 and omega-6).

There are a lot of people who disagree with you on this testosterone thing. The whole bodybuilding community on the internet for example. :D


http://www.musculard...stosterone.html

[misterE]

I don't think these graphs show anything. The first, between total T and SHBG isn't much of a correlation

Surely you're kidding... look at how diagonal the "average-line" is: if that's not a clear correlation, I don't know what is!

The second graph, which is more or less a graph of free T vs SHBG, looks like a 'correlation' of almost exactly zero.

True, but the correlation is still there (albeit small). This proves that SHBG mainly influences the total-amount of testosterone (much) more than the "free" fraction.

What's the SHBG receptor and how does it fit into your argument?

Basically, (from studying the works of Dr. William Rosner) hormones that are bound to SHBG are still able to function, even thou they cannot enter the cell nucleus. They do this by binding to the SHBG-receptor outside of the cell-membrane. The actions of hormones bound to SHBG are very tightly monitored and very closely regulated, unlike free-hormones.

[hivemind]

http://www.ncbi.nlm....Pubmed_RVDocSum

Mean plasma concentrations of total and sex-hormone-binding-globulin (SHBG)-bound testosterone were 13% and 15% higher, respectively, on the high-fat, low-fiber diet and the difference from the low-fat, high-fiber diet was significant for the SHBG-bound fraction (P = 0.04).

[misterE]

There are a lot of people who disagree with you on this testosterone thing. The whole bodybuilding community on the internet for example. :D

I know. I refer to these people as laymen. Anyone who has invested research into SHBG should know that SHBG is a very good thing. I suggest you look at the relationship between diabetes and SHBG, or obesity and SHBG, or heart-disease and SHBG, or cancer and SHBG... the list goes on and on.

[niner]

I refer to these people as laymen.

Do you have training in the life sciences?

[Hebbeh]

SHBG receptors are not a major player. They are only present in a very few select tissues which doesn't include muscle. And nobody really knows what these receptors do except drive cAMP however Testosterone is a bigger driver of cAMP so increased SHGB is 1 step forward and 2 back in regards to Testosterone and cAMP. Muscle drives metabolism directly and indirectly and Testosterone is the major player. Bodybuilders and athletes take Testosterone to enhance performance not SHBG...in fact, they take drugs to inhibit SHBG because that is what works. SHBG has an inverse relationship to libido or sex drive. This can easily be tested by taking drugs to inhibit SHBG and noting the effects...amazing in that regard I can assure you. And in regards to your original post...to promote a vegan diet....current research shows that in regards to diet and nutrition, there is no one size fits all. Current research shows that different people have different genetic propensities for different macro nutrient ratios. Some are genetically inclined to paleo type diet, some Mediterranean type diet, some a higher fat diet, and some a lower fat diet. This can be determined from DNA. But I haven’t read of any genes to advocate a vegan diet. As far as any well know athletes excelling on a vegan diet, I can assure you they are not eating a run of the mill vegan diet but certainly are supplementing large quantities of protein powder....probably either pea and/or rice and/or soy protein isolates...and as such, is not a "natural" or typical vegetarian diet. I have had my DNA tested by 23andme and they have verified that my genetic fingerprint indicates I would do better on a low fat diet....which is what I have always found...I eat high carb but get my carbs from lots of veggies and fruits....but I'm far from a vegetarian...I eat a lot of lean protein. I have posted my 23andme results in the C60 thread in regards to comments about whether high fat diets are the best diet for everybody (they are not) But the main point is no one size fits all. I could say a lot more dig up studies but I worked 12 hours to day and then hit the gym for an hour...and getting some sleep (which is crucial for testosterone) is more important so I can get up and do it again tomorrow. Anyway, I've found what works for me and works very well....and I wish you the best of luck.


Edit: and wanted to add that comparing a vegetarian diet to the typical western junk food and fast food garbage diet is not comparing apples to apples. You will not find anybody on this forum eating McD's and Burger King. That is the major flaw with your studies. If you want a real comparison, compare your diet to mine....not some obese couch potato junk food addict.

Edited by Hebbeh, 13 July 2012 - 04:05 AM.

[misterE]

http://www.ncbi.nlm....Pubmed_RVDocSum

Mean plasma concentrations of total and sex-hormone-binding-globulin (SHBG)-bound testosterone were 13% and 15% higher, respectively, on the high-fat, low-fiber diet and the difference from the low-fat, high-fiber diet was significant for the SHBG-bound fraction (P = 0.04).

You can always find contradicting studies, here are two studies showing that high-fat diets decrease SHBG [1-2].




[1] J Clin Endocrinol Metab. 1987 May;64(5):1083-5. Dietary lipids: an additional regulator of plasma levels of sex hormone binding globulin. Reed MJ, Cheng RW, Simmonds M.

[2] Ann N Y Acad Sci. 1988;538:280-6. Hormonal and nonhormonal factors affecting sex hormone-binding globulin levels in blood. Thijssen JH.

[misterE]

Do you have training in the life sciences?

Can you clarify the question please? I don't understand what you are asking.

[misterE]

SHBG has an inverse relationship to libido or sex drive.

And how can this be true? I just showed plenty of studies showing that SHBG is inversely related to metabolic-syndrome. And erectile-dysfunction and metabolic-syndrome go hand in hand [1-3]. Take a look at the following abstracts:



Int J Impot Res. 2009 Mar-Apr;21(2):89-98.
Obesity, low testosterone levels and erectile dysfunction.
Diaz-Arjonilla M, Schwarcz M, Swerdloff RS, Wang C.

Abstract

Obesity is an important risk factor for many common diseases including cardiovascular disease (CVD), type 2 diabetes, cancer and erectile dysfunction (ED). Adipose tissues produce a number of adipokines and cytokines, which affect endothelial and metabolic function resulting in insulin resistance and the metabolic syndrome (risks factors for CVD). Both ED and metabolic syndrome improve with a reduction in body mass index (BMI). The relationships among obesity, metabolic syndrome, ED, sex hormone-binding globulin (SHBG) and serum total and free testosterone levels are complex and often confusing to the physician. It is known that BMI is inversely proportional to serum total testosterone concentrations; low serum SHBG levels in obesity contribute to the low serum total testosterone. Recent studies show that BMI is also inversely proportional to free testosterone concentration. The characteristic low serum testosterone concentrations observed in obese men are also present in men with the metabolic syndrome and type 2 diabetes mellitus. A small proportion of men with ED have hypogonadism; however, the proportion increases if these men are obese with manifestations of the metabolic syndrome or type 2 diabetes mellitus. ED is a common symptom in patients with type 2 diabetes who also have low testosterone levels. This review describes the relationships between low serum testosterone concentrations and ED in obese patients and those with metabolic syndrome and type 2 diabetes mellitus.




Cardiol J. 2009;16(4):300-6.

Hormonal profiles behind the heart of a man.
Sarkar NN.

Abstract

This study focuses on the role of sex steroids on the libido, sexual life, emotional and physiological heart of men of all ages. Sex steroids play a significant role throughout a man's life, with a gradual decline in old age. The foetal testis secretes testosterone and dehydroepiandrosterone at about nine weeks gestation. At puberty, testosterone increases dramatically in boys. Changes in weight and height of boys across this period are associated with increasing testosterone concentration and sex hormone binding globulin (SHBG). Romantic thoughts, fantasy, and sexual pleasure-seeking behaviour in adolescents are associated with exposure to high androgens secretion. Thus, the libido and sexual life of a man is initiated and maintained by testosterone and SHBG. Lower testosterone levels are associated with erectile dysfunction among other risk factors: diabetes, hypertension, heart disease, psychological stress and obesity. Men with proven coronary atherosclerosis have lower levels of testosterone and SHBG, which have negative correlation with very low-density lipoprotein, triglycerides, body mass index and body fat mass. These are some of the risk factors for cardiovascular diseases. Thus, in men, endogenous sex steroids impart beneficial effects on the heart. How exactly endogenous sex steroids act on the heart is not clear. Further study is needed to understand the interaction between endogenous sex steroids, higher centers in the brain and the heart of a man.





[1] Sex Med. 2009 Nov;6(11):2958-75.Metabolic syndrome and sexual (dys)function. Borges R, Temido P, Sousa L,

[2] Int J Impot Res. 2009 Mar-Apr;21(2):89-98. Epub 2008 Oct 9. Obesity, low testosterone levels and erectile dysfunction. Diaz-Arjonilla M, Schwarcz M, Swerdloff RS,

[3] Diabetes Care. 2011 Jul;34(7):1669-75. Low testosterone associated with obesity and the metabolic syndrome contributes to sexual dysfunction and cardiovascular disease risk in men with type 2 diabetes. Wang C, Jackson G, Jones TH,

Some are genetically inclined to paleo type diet, some Mediterranean type diet, some a higher fat diet, and some a lower fat diet. This can be determined from DNA. But I haven’t read of any genes to advocate a vegan diet..

Then you must not have heard about the amylase-gene. Amylase is the largest digestive enzyme in the human-body. It's sole purpose; to digest starch! We would not have this gene if we weren't made to digest mainly starchy foods [1]. Plus the human brain prefers glucose as an energy source... this is pretty good indication that humans should be eating plenty of glucose. The best sources of glucose are gains, beans and potatoes.


[1] Nat Genet. 2007 Oct;39(10):1256-60. Diet and the evolution of human amylase gene copy number variation. Perry GH, Dominy NJ, Claw KG, Lee AS.

Edited by misterE, 13 July 2012 - 04:45 AM.

[Hebbeh]

SHBG has an inverse relationship to libido or sex drive.

And how can this be true? I just showed plenty of studies showing that SHBG is inversely related to metabolic-syndrome. And erectile-dysfunction and metabolic-syndrome go hand in hand [1-3]. Take a look at the following abstracts:



Int J Impot Res. 2009 Mar-Apr;21(2):89-98.
Obesity, low testosterone levels and erectile dysfunction.

Diaz-Arjonilla M, Schwarcz M, Swerdloff RS, Wang C.

Abstract

Obesity is an important risk factor for many common diseases including cardiovascular disease (CVD), type 2 diabetes, cancer and erectile dysfunction (ED). Adipose tissues produce a number of adipokines and cytokines, which affect endothelial and metabolic function resulting in insulin resistance and the metabolic syndrome (risks factors for CVD). Both ED and metabolic syndrome improve with a reduction in body mass index (BMI). The relationships among obesity, metabolic syndrome, ED, sex hormone-binding globulin (SHBG) and serum total and free testosterone levels are complex and often confusing to the physician. It is known that BMI is inversely proportional to serum total testosterone concentrations; low serum SHBG levels in obesity contribute to the low serum total testosterone. Recent studies show that BMI is also inversely proportional to free testosterone concentration. The characteristic low serum testosterone concentrations observed in obese men are also present in men with the metabolic syndrome and type 2 diabetes mellitus. A small proportion of men with ED have hypogonadism; however, the proportion increases if these men are obese with manifestations of the metabolic syndrome or type 2 diabetes mellitus. ED is a common symptom in patients with type 2 diabetes who also have low testosterone levels. This review describes the relationships between low serum testosterone concentrations and ED in obese patients and those with metabolic syndrome and type 2 diabetes mellitus.




Cardiol J. 2009;16(4):300-6.
Hormonal profiles behind the heart of a man.

Sarkar NN.
Abstract

This study focuses on the role of sex steroids on the libido, sexual life, emotional and physiological heart of men of all ages. Sex steroids play a significant role throughout a man's life, with a gradual decline in old age. The foetal testis secretes testosterone and dehydroepiandrosterone at about nine weeks gestation. At puberty, testosterone increases dramatically in boys. Changes in weight and height of boys across this period are associated with increasing testosterone concentration and sex hormone binding globulin (SHBG). Romantic thoughts, fantasy, and sexual pleasure-seeking behaviour in adolescents are associated with exposure to high androgens secretion. Thus, the libido and sexual life of a man is initiated and maintained by testosterone and SHBG. Lower testosterone levels are associated with erectile dysfunction among other risk factors: diabetes, hypertension, heart disease, psychological stress and obesity. Men with proven coronary atherosclerosis have lower levels of testosterone and SHBG, which have negative correlation with very low-density lipoprotein, triglycerides, body mass index and body fat mass. These are some of the risk factors for cardiovascular diseases. Thus, in men, endogenous sex steroids impart beneficial effects on the heart. How exactly endogenous sex steroids act on the heart is not clear. Further study is needed to understand the interaction between endogenous sex steroids, higher centers in the brain and the heart of a man.





[1] Sex Med. 2009 Nov;6(11):2958-75.Metabolic syndrome and sexual (dys)function. Borges R, Temido P, Sousa L,

[2] Int J Impot Res. 2009 Mar-Apr;21(2):89-98. Epub 2008 Oct 9. Obesity, low testosterone levels and erectile dysfunction. Diaz-Arjonilla M, Schwarcz M, Swerdloff RS,

[3] Diabetes Care. 2011 Jul;34(7):1669-75. Low testosterone associated with obesity and the metabolic syndrome contributes to sexual dysfunction and cardiovascular disease risk in men with type 2 diabetes. Wang C, Jackson G, Jones TH,

Some are genetically inclined to paleo type diet, some Mediterranean type diet, some a higher fat diet, and some a lower fat diet. This can be determined from DNA. But I haven’t read of any genes to advocate a vegan diet..

Then you must not have heard about the amylase-gene. Amylase is the largest digestive enzyme in the human-body. It's sole purpose; to digest starch! We would not have this gene if we weren't made to digest mainly starchy foods [1]. Plus the human brain prefers glucose as an energy source... this is pretty good indication that humans should be eating plenty of glucose. The best sources of glucose are gains, beans and potatoes.


[1] Nat Genet. 2007 Oct;39(10):1256-60. Diet and the evolution of human amylase gene copy number variation. Perry GH, Dominy NJ, Claw KG, Lee AS.

I know it to be true from experience (and trust me on that) and the experiences that other athletes have shared. Forget your studies. Studies on fat couch potatoes are worthless. How many obese couch potatoes do you really think you are going to find on this forum. Let’s talk about the typical member of this forum. People that walk the walk....live a healthy lifestyle....exercise and eat right (for their genetic type)....not the typical couch potato the comes home, grabs a beer and plops down on the sofa with a bag of chips in front of the boob tube (which I don't own) and then laments about their poor health and ED....that is what your studies are about....which makes them worthless.

And read up about we all being genetically unique...and as such, like I said before, there is no one size fits all.....it's up to you to find what works for YOU based on the genes YOU were born with....optimizing YOUR potential....which you won't find by living an unhealthy lifestyle...and then trying to compare it to my healthy lifestyle. These studies are based on unhealthy people....apples to oranges...The problem should be obvious.

Edited by Hebbeh, 13 July 2012 - 05:00 AM.

[niner]

Do you have training in the life sciences?

Can you clarify the question please? I don't understand what you are asking.

By calling people who disagree with you "laymen", you're implying that you are a professional, i.e. a biochemist, endocrinologist, or some such thing. Yet you see correlations in plots that look like shotgun blasts, which is not the sort of thing a scientist would do. So I'm guessing that you are self-taught.

SHBG has an inverse relationship to libido or sex drive.

And how can this be true? I just showed plenty of studies showing that SHBG is inversely related to metabolic-syndrome. And erectile-dysfunction and metabolic-syndrome go hand in hand [1-3].

Another clue that you aren't trained in science is that you keep confusing correlation with causation.