Decline in Serum Testosterone Levels Among Adolescent and Young Adult Men in the USA

[AndrogenHacker]

Decline in Serum Testosterone Levels Among Adolescent and Young Adult Men in the USA - ScienceDirect

Abstract:

Testosterone deficiency has a prevalence of 20% among adolescent and young adult (AYA) males. Although previous studies have shown that total testosterone (TT) levels are declining in the population compared to prior decades, no study has identified TT level trends for AYA males specifically. Using data from the National Health and Nutrition Examination Surveys, we investigated TT levels for 4045 men from 1999 to 2016. After controlling for confounders, we found that mean TT levels declined over time: TT levels were lower in the later (2011–2016) than in the earlier (1999–2000) cycles (all p < 0.001). Elevated body mass index (BMI) was associated with lower TT, but the trend remained significant even among men with normal BMI. Limitations include the influence of confounding variables such as environmental factors and the use of differing assays for TT measurement. Further studies using other data streams are needed to validate these findings.

So sad.

 

[Deleted member 43589]

Decline in Serum Testosterone Levels Among Adolescent and Young Adult Men in the USA - ScienceDirect

Abstract:



So sad.

OK, I will try to revive this one......WHY IS THIS HAPPENING>

Travison TG, Araujo AB, O'Donnell AB, Kupelian V, McKinlay JB. A population-level decline in serum testosterone levels in American men. J Clin Endocrinol Metab. 2007 Jan;92(1):196-202. doi: 10.1210/jc.2006-1375. Epub 2006 Oct 24. PMID: 17062768.\

Conclusions: These results indicate that recent years have seen a substantial, and as yet unrecognized, age-independent population-level decrease in T in American men, potentially attributable to birth cohort differences or to health or environmental effects not captured in observed data.

So again, why is this happening. Food changes, environmental influences? What is going on that the male testosterone rates are falling so quickly?

Travison TG, Araujo AB, Kupelian V, O'Donnell AB, McKinlay JB. The relative contributions of aging, health, and lifestyle factors to serum testosterone decline in men. J Clin Endocrinol Metab. 2007 Feb;92(2):549-55. doi: 10.1210/jc.2006-1859. Epub 2006 Dec 5. PMID: 17148559.

The relative contributions of aging, health, and lifestyle factors to serum testosterone decline in men - PubMed

Both chronological aging and changes in health and lifestyle factors are associated with declines in serum T. Comorbidities and lifestyle influences may be as strongly associated with declining T levels as is aging itself over the short- to midterm. These results suggest the possibility that...

pubmed.ncbi.nlm.nih.gov

Conclusions: Both chronological aging and changes in health and lifestyle factors are associated with declines in serum T. Comorbidities and lifestyle influences may be as strongly associated with declining T levels as is aging itself over the short- to midterm. These results suggest the possibility that age-related hormone decline may be decelerated through the management of health and lifestyle factors.

Declining Male Fertility Linked To Water Pollution

New research strengthens the link between water pollution and rising male fertility problems. The study shows for the first time how a group of testosterone-blocking chemicals is finding its way into UK rivers, affecting wildlife and potentially humans.

www.sciencedaily.com

 

[Deleted member 43589]

Lower Serum Testosterone Associated with Elevated Polychlorinated Biphenyl Concentrations in Native American Men | Environmental Health Perspectives | Vol. 117, No. 9

BackgroundPolychlorinated biphenyls (PCBs) and chlorinated pesticides are endocrine disruptors, altering both thyroid and estrogen hormonal systems. Less is known of action on androgenic systems.ObjectiveWe studied the relationship between serum concentrations of testosterone in relation to...

ehp.niehs.nih.gov

Serum Testosterone Concentrations and Urinary Bisphenol A, Benzophenone-3, Triclosan, and Paraben Levels in Male and Female Children and Adolescents: NHANES 2011–2012 - PMC

Exposure to environmental phenols (e.g., bisphenol A, benzophenone-3, and triclosan) and parabens is widespread in the population. Many of these chemicals have been shown to have anti-androgenic effects both in vitro and in vivo. We examined the ...

www.ncbi.nlm.nih.gov

 

[Systemlord]

Conclusions: Both chronological aging and changes in health and lifestyle factors are associated with declines in serum T. Comorbidities and lifestyle influences may be as strongly associated with declining T levels as is aging itself over the short- to midterm. These results suggest the possibility that age-related hormone decline may be decelerated through the management of health and lifestyle factors.

Yesterday I was reading about a Hawaiian island where disease is rare as well as dementia in the elderly and they live longer. However if the people relocated to another part of the developed world, their health benefit from living on the island vanished and risk factors for disease went up!

 

[Deleted member 43589]

Yesterday I was reading about a Hawaiian island where disease is rare as well as dementia in the elderly and they live longer. However if the people relocated to another part of the developed world, their health benefit from living on the island vanished and risk factors for disease went up!

I saw a documentary on that as well on PBS. The people hunted food, at fish and grew the rest. As people started visiting the island they started to replace their food with carbohydrates, cereals chips etc. In time they started seeing obesity, CHD, diabetes and the likes as people changed their eating habits and got less exercise. That should be an eye opener for America but the carbohydrate industry has a lot of money. This country has done little to get people to be more active and change their diets. Seems though research has found that obesity has nothing to do with low testosterone rates.

 

[MDavidW76]

I saw a documentary on that as well on PBS. The people hunted food, at fish and grew the rest. As people started visiting the island they started to replace their food with carbohydrates, cereals chips etc. In time they started seeing obesity, CHD, diabetes and the likes as people changed their eating habits and got less exercise. That should be an eye opener for America but the carbohydrate industry has a lot of money. This country has done little to get people to be more active and change their diets. Seems though research has found that obesity has nothing to do with low testosterone rates.

Very common in all indigenous populations. I saw firsthand back home in Canada.

 

[bixt]

So, when dialing in you want to hit the sweet spot. Too little T and no benefit. Too much T and too many side effects. So that sweet spot in the middle, is your dialed in dose.

So no matter how many articles are posted on declining T in populations, PCBs, your great grandfathers T levels when he was 16, etc etc etc, it shall not have any effect on your sweet spot dialled in dose. Your grandfathers TT is not the missing link on why you dont feel well. Levels in the 1940 do not magically shift today your sweet spot towards a higher TT or dose. You could be completely oblivious to lab ranges today or 50 years ago as they have zero impact in determining your sweet spot, based on how you feel, today.

 

[doyouwantbirds]

So I've been looking into this for a while and got dissatisfied with the research. I had some questions - how long has it actually been falling and do levels differ around the world? (this could tell us what is causing the drop) I found an incredible lack of published research into those questions, so I aggregated the results of about 1000 individual unrelated studies to answer my questions. Here's my site for more detailed info: Testosterone Levels 100 Years Ago - TestosteroneDecline.com

Here's what I found:

• It's hard to tell, but testosterone appears to have begun falling at least in the early 1980's, but I think earlier than that. I have very sketchy research that it may in fact have been falling since the WW2 era.
• In the 1970's and before it was at an average of 700 ng/dl. As you know today's average is about 400 ng/dl. It has been steadily falling over the decades. That's a much bigger decline than these studies that show it falling 20% or whatever since the year 2000 or something like that.
• Regions it has fallen hard: North America, Latin America, All of Europe, East Asia, Kazakhstan. These are the 700 dropping to 400 places.
• It has fallen less in the Middle East, North Africa, Southeast Asia.
• It is still high, no drop, in most of Subsaharan Africa, Central Asia (except Kazakhstan), and Siberia. These places are still around 700 ng/dl on average.
• In Central America and Kazakhstan it is extraordinarily low - Kazakhstan is in the low 300's on average. Kazakhstan also has a very high incidence of reproductive organ developmental defects and conditions. To me it's clear that there's something weird going on there, in the environment. Perhaps it is radiation from the Soviet nuclear testing that was done in Kazakhstan for decades?
• Everywhere that I could see originally had equivalent testosterone levels, which were plenty high naturally, around 700 ng/dl. So I don't think there's much of any "natural" variation of testosterone levels by region. It seems to be due to some kind of environmental stressor.
• Hunter-gatherers and nomadic tribes mostly have very high testosterone, just as you might have guessed. Most of them are something like 900 ng/dl on average. However, there are a few that are not so high. This is probably due to plain malnutrition.
• I did some very questionable research, by looking up historical testicle size (haha i know) that suggested testosterone may have been about 900 ng/dl on average in the western world in the 18th,19th, and the first half of the 20th centuries.

I found that low testosterone in a region correlated with two things that I checked for:

• Agricultural chemicals used (Latin America uses a ton of them, Subsaharan Africa currently doesn't)
• Polyunsaturated fat (PUFA) in the diet (the worst kind is the degraded omega-6 seed oils that junk food is fried in) And PUFA consumption also correlates with low test in individuals too.

 

[Deleted member 43589]

My doctor suggested this one.....

Duan L, Zhu J, Wang K, Zhou G, Yang Y, Cui L, Huang H, Cheng X, Ba Y. Does Fluoride Affect Serum Testosterone and Androgen Binding Protein with Age-Specificity? A Population-Based Cross-Sectional Study in Chinese Male Farmers. Biol Trace Elem Res. 2016 Dec;174(2):294-299. doi: 10.1007/s12011-016-0726-z. Epub 2016 May 6. PMID: 27154732.

Does Fluoride Affect Serum Testosterone and Androgen Binding Protein with Age-Specificity? A Population-Based Cross-Sectional Study in Chinese Male Farmers - PubMed

Many studies have demonstrated that exposure to excess fluoride was associated with a variety of diseases. Little is known about the variation of testosterone (T) levels caused by fluoride exposure. The aim of this study is to explore the association of fluoride exposure and age with serum T and...

pubmed.ncbi.nlm.nih.gov

Fluoride-induced disruption of reproductive hormones in men

Fluoride-induced reproductive effects have been reported in experimental models and in humans. However, these effects were found in heavily exposed sc…

www.sciencedirect.com

In 1945, Grand Rapids, Michigan, became the first community in the world to add fluoride to tap water.