Testosterone — new discoveries about the male hormone | DW Documentary

testosterone is the most important male sex hormone men who are heavily influenced by testosterone are said to be egotistical and they enjoy taking risks but a number of European scientists have been trying to find out whether testosterone is really as bad as its reputation we’ve come to the munster University Hospital to talk to doctor Michels it’s man a German specialist in the treatment of diseases that affect men he is also an expert on hormones Tesla stolen is swoosh tanisha feeder dinging testosterone is responsible for the development of a number of male physical characteristics including hair patterns on the head it also determines beard growth affects muscles and a man’s overall personality it’s a much more complex hormones than some people might think too often s indicting encanta most testosterone is produced in the testes but a small amount comes from the adrenal cortex the specific sources of testosterone are the lydic cells the hormones that are responsible for developing male characteristics in the body are called androgens the most important androgen is testosterone levels of testosterone rise dramatically during puberty and then remain at a high level but researchers have also found significant short-term increases in this hormone immediately after birth – Asians claw varoom does Perseid as shrine ABBA it’s hard to say why that happens but it seems to be a part of the maturation process in the brain and in the male reproductive system the spirit of a monastic were hopes of mukesh young christian wolff lives in Heilbronn at the age of 20 he discovered that he had too little testosterone in his body doctors later determined that the cells in his brain were not sending out the proper production signals the cause of the problem wasn’t clear at first wolf had a hard time even describing the symptoms it took a long time for doctors to come up with a proper diagnosis as vondopoulos concerts man realizing that something was wrong was a gradual process it didn’t happen overnight feeling worse and worse I had no energy at all and no sex drive either but I could feel something just wasn’t right then I was diagnosed with depression and I realized that something was seriously wrong with me wolf was a medical student at the time and a bodybuilder he kept a close eye on his metabolism and testosterone levels but they couldn’t figure out what was going on I got along well with my family and had a girlfriend I was doing well at school and then I figured out that this might have something to do with the testosterone deficiency so I had some tests done and the levels turned out to be about zero that’s a bit low isn’t essential vanish how much testosterone do men actually need in tuition it’s on average men have at least eight to twelve nanomoles per liter of testosterone toises anything below that represents a deficiency but the amount also depends on genetics I’m a single machine Finnegan a tech woman’s testosterone levels are much lower about five to ten percent that of men they use the testosterone to synthesize estrogen system the primary female sex hormone through the fut is that synthesis is carried out by an enzyme called aromatisse it can be found in cells in several parts of the body including the brain adrenal glands ovaries and testes in the face of such testosterone levels Christian Wulff chose a potentially risky form of medical treatment we’ll sit out okay messiahfest I knew I needed hormone replacement therapy after other possible causes like vitamin D or

zinc deficiency had been ruled out wasn’t one of the side effects of hormone replacement therapy is that it suppresses sperm production which can cause infertility testosterone and covered testosterone is naturally produced in the testicles but the process begins in the brain specifically in the hypothalamus sign and sleep Danna sent our destroyer ironhide’s it links the body’s nervous system to the endocrine system through the pituitary gland unrelated to perfuse the pituitary gland is divided into two sections the anterior portion produces two key hormones LH and FSH LH is responsible for stimulating the production of testosterone in the testes FSH contributes to the production of sperm these two hormones report back to the brain on whether the body is producing enough testosterone and sperm the brain adjust the amounts of each as necessary in the test system even testosterone replacement therapy suppresses the hormones in the pituitary gland that are responsible for sperm production it’s like a birth control pill v and the pure feeling man eyes don’t look too feminine Budong but if a man is testosterone deficient and wants to have children we have to take a different approach low testosterone can have serious effects on the body but can too much of this hormone make men overly aggressive this is Leone home of Frances Center for cognitive neurosciences jean-claude Rhea is a research director here Draya has been studying the influence of testosterone on human behavior and he’s found little evidence that testosterone strokes aggression in men to the effect that testosterone has on human behavior is by no means clear but there is some indirect evidence example high levels of testosterone have been found in some prison inmates who have committed serious crimes and we did a study which indicated that patients who are given testosterone injections could become more aggressive it’s only 50 million new condition testosterone can also actually improve social behaviors noxee pal some problems related CBT so at this point there’s little hard evidence pointing to a link between increased levels of testosterone and aggressive behavior drea conducted an experiment to try to prove or disprove these claims his first task was to measure the testosterone levels in the participants blood testosterone is a fat-soluble hormone so it can pass through the membranes of cells bind with hormone receptors and then produce changes in the cell’s structure testosterone can be identified and measured in various bodily fluids including saliva urine and blood before the experiment begins one group of participants is injected with testosterone the other group is given a placebo we tried to determine whether the increase in testosterone levels would contribute to a change in behavior this graph shows that both groups started out with approximately the same level of testosterone injections then we gave one group testosterone injections and recorded the increase in the level of this hormonal system now the test subjects are going to take part in a game exercise called ultimatum the game is frequently used in behavior research it’s designed to test whether a person is generous or selfish one of the players is given a sum of money and is required to share part of it with the other if the second player accepts the offer the deal goes ahead as planned but if he rejects it neither player gets any money at this point we observed no difference between the player who had been given testosterone and the one who has until into systole and I said that now the rules of the game are going to change a bit the players will be able to use the money to reward fair behavior or punish unfair behavior and this is where Draya and his colleagues observed a difference between the player who got an extra dose of testosterone and the one who didn’t

silver bishop team miss Cruz it’s a subtle difference and we confirmed it only in the second stage of the experiment the group administered with extra testosterone imposed a more severe punishment when they believed that they hadn’t been given enough money but at the same time they also reacted more positively when given more money than expected we observed a big difference in the behavior of the two groups even loop-de-loop so can testosterone also stimulate generosity in men the researchers were surprised by the results but the situation is more complex than that Draya says there’s a subconscious motivation at work here this phenomenon shows clearly that you can improve your social status if you cooperate with people or engage in other kinds of positive social behaviors utility so while testosterone can influence aggression it also plays a role in the ability to act with generosity so the noise State drea has been looking for more evidence to support his theory on the influence of testosterone so he’s been studying brain activity 30 system testosterone based behavior can improve the man social status and that process could be linked to various mechanisms in the brain particularly a group of neural structures known as the reward system baltimore improved social status generates a sense of well-being like a reward that may explain the boasting trade commonly associated with excessive manly behavior to god there’s always a motivation behind generosity if someone sees you being generous they’re more likely to think highly of you for example men will probably be more generous if they know that they are being observed by women cubes this indicates another link between testosterone and generous behavior so testosterone may be responsible for positive and negative behavior in both cases this behavior seems to be directed at preserving or even improving social status psychologist Pranjal Mehta is an associate professor at University College in London his research focuses on how hormones particularly testosterone influence human behavior the evidence for that myth that testosterone is directly related to masculine traits like aggression has not worn out in the data so there are plenty of results suggesting that testosterone is either weekly or unrelated to aggressive behavior at all in in humans including human males so the field is still trying to unpack these kinds of effects to understand when testosterone might be related to other behaviors like helping and pro-social behavior as well meta has carried out an experiment that involves the ultimatum game similar to the one we saw earlier it’s actually a way to look at two kinds of behaviors one is trust to what extent is the first-mover trusting and two to look at reciprocity of trust if someone is hyper trusting is the second move are going to reciprocate that trust as in the experiment carried out by jean-claude rhea one player was given an extra dose of testosterone the other player was given a placebo the experiment will measure the level of trust between the two the player administered testosterone can use his money to make sure that the other player also profits but will the second player give back some of his winnings as a gesture of gratitude or will he keep it all for himself we found two interesting effects first is consistent with the stereotype testosterone reduced trust in the first mover so that is somewhat consistent with the stereotype testosterone being related to competitiveness and threatened the environment and maybe mobilizing more selfish social behaviors

right so I want to keep the money next the players reverse their roles in both tests the player with the extra testosterone shares his winnings with the other this is an example of pro-social behavior we know that reciprocity in cooperative situations that is going to Gardner status and what we found is that testosterone boosted reciprocity and we’re arguing that in a cooperative environment it’s again as through prestige and pro-social behaviors that you gain status and so though in those situations testosterone actually might boost pro-social behavior Mehta is convinced that testosterone plays a much more complex role in human behavior than researchers previously thought for example it can promote socially positive behavior but there’s always a motivating factor behind that behavior you can imagine when we think about our leaders and people in positions of power they have expertise knowledge and experience that they’re gonna relay to their subordinates that’s part of being a good leader that’s also part of some definitions of power where you’re helping others as a way to influence others in some way so you can think of it as pro-social but it’s also in some definitions an exertion of power but concepts such as masculinity status and power are perceived differently in various cultures around the world we’ll the test results differ from one country to the next so my laboratories in London someone else’s laboratory is in Germany someone else’s laboratory is in a rural part of the south of the United State that should see erratically be expected to change the results but the effects of testosterone on the human body are the same regardless of culture and geography when Christian Wulff found out that he was infertile he started looking for solutions my mother took me to see a urologist and he told her that I will never have children but I could have a superlative sex life my mom didn’t think it was funny so I started reading up on my conditioners in dusty my lines of folks are is there a medical solution to infertility caused by testosterone deficiency doctors it’s Minh offers some hope when a man kena wound shut wound license one of the things we can do for men who suffer from this problem is to give them injections of ganado tropen hormones giggity happy Mike his form of treatment has been used for years even decades it seemed and becomes the gonadotropins include LH which is responsible for the production of testosterone in the testes and FSH which contributes to the production of sperm the treatment was successful for Christian Wulff his body was able to produce testosterone and fertile sperm for a short period of time he had the sperm frozen for later use he starts to nuts and if I had listened to what the doctors told me at first it would have ended right there but now I can have children all over Schulte eyes is a professor of psychology at Friedrich Alexander University in Erlangen his research work focuses on how testosterone affects the body specifically bone growth effective on testosterone testosterone and estradiol its counterpart in females contribute significantly to bone strength and density from prenatal development to maturity on this we income and somebody I’m in that is asked for example during the first three months of pregnancy testosterone causes the ring fingers of the male fetus to grow longer than the index fingers short ice notes that in general women’s index fingers are longer than their ring fingers in men it’s just the opposite you can see that in this image of a man’s hand the index finger is clearly shorter than the ring finger testosterone clearly has an influence on

bone growth even in the early stages of pregnancy it may also be responsible for the early development of the so-called power motive yes isn’t shaft Liam Priscilla – Sean Service is that a scientist I’m interested in finding out where that motive comes from I suspect that its origins can be found in biology here salt ice is conducting an experiment in which the participants write a fantasy narrative this may help him to determine whether they are motivated by power the power motive is a common human characteristic that involves one person’s efforts to have an impact on the behavior of others this motivation does not necessarily manifest itself in conscious attitudes or the beliefs that we have about ourselves our research indicates that the way we perceive ourselves actually has little to do with what makes us tick and what influences our spontaneous behaviors from influence this part of the experiment involves a series of 10 tests aimed at finding out how the participants respond to victory or defeat the test results can be manipulated one participant can win up to eight of the ten rounds the researchers want to find out whether any changes take place in the test subjects hormone levels we found that the power motive plays a role in their response to winning or losing those who won had higher levels of testosterone than those who lost even Phyllida and if one of the participants is not motivated by power but wins it has no effect on the amount of testosterone in his system we can’t say that winning or losing is exclusively responsible for changes in testosterone levels we have to take into account factors such as the individual’s personality and motivation but those factors are shaped by testosterone during fetal brain development clicked human thick lung but does it all come down to testosterone and its influence in determining for example male finger length and the development of the power motive women have only 10% of the testosterone levels found in men does that mean that they are less motivated by power we are invited of the space colony and vibe there’s evidence that indicates that there is a connection between the length of woman’s fingers and the power motive complex it’s a complex situation that will require a lot more research scientists have learned more in recent years about female sex hormones but the relationship between women and power has not been widely studied the field has focused on male reproductive system and males for the past hundred years and has largely neglected looking at female sex hormones in the context of status and leadership and this is this is a large gap in the literature today we’ve come to the University of Cambridge to talk to clinical psychologist Simon baron-cohen part of his research focuses on how gender affects human behavior in general and the brain in particular we’ve been looking at sex differences in the mind between males and females on average and one of their tests that we use is where you have to find a shape that’s hidden in a design as quickly as you can and we find that on average men are faster at finding this target hidden in the overall design Baron Cohen and his colleagues conducted behavioural studies of children and adolescents they started by testing hormone levels in numerous samples of amniotic fluid the liquid that helps protect the fetus in the womb we’ve measured the testosterone during pregnancy in the womb in the amniotic fluid so this is the baby in the womb and some women during pregnancy have a clinical procedure it’s called amniocentesis where a needle goes into that fluid to take out some of the fluid and we can measure

testosterone in the fluid and babies vary in terms of how much of the hormone they are exposed to so boys show more more testosterone than girls in the amniotic fluid in the early stages of fetal development the genitalia show no signs of gender distinction but after approximately the seventh week of gestation a gene on the Y chromosome can activate a process that results in the development of testicles later testosterone plays a role in the development of masculine characteristics in several parts of the male fetus including the brain we’re looking at these long-term effects of the hormones presumably mediated by changes in brain development so we’re measuring the behavior but the assumption is that the hormones have changed brain development in males and females because they’re exposed to different amounts of the hormone after the babies and baron-cohen study were born he measured and analyzed their reaction to a series of images what we found was that the higher the child’s prenatal testosterone the less eye contact the child makes at their first birthday so this was them a surprise for us because you would think iContact is influenced by social factors but actually it seems to also be influenced by prenatal testosterone the children were tested again at the age of two the results indicated that girls more actively sought eye contact than boys did and had better verbal skills they talked earlier and their language develops faster what we didn’t know is why why do girls have this advantage in language development but now we could relate it back to the prenatal testosterone because we found that children who had a higher prenatal testosterone had smaller vocabularies years later baron-cohen conducted more tests on the children they were shown images of various facial expressions and were asked to describe the emotion the images portrayed and again we found that the higher the child’s prenatal testosterone the more difficulty they have on this test of empathy which is a surprise again for us because we’re finding there’s even there it’s eight years later since we measured the testosterone there’s still an effect that we’re observing to sum up girls did better on tests that involved verbal and social skills boys were better at developing analytical skills the same hormone seems to be involved not only in social development like reading faces and language and eye contact but also in non social skills like pattern recognition and and taking things apart to see parts within the homes a bit like on the rubic cube where you have to see the pattern very quickly the tests indicate that boys better able to understand abstract concepts but have less empathy Baron Cohen has used the findings to support his theory of a possible link between testosterone and autism we looked at the relationship between typical sex differences in autism because what is amiss more common in boys so we were trying to understand why why why why does being a boy lead you to a higher likelihood that you’ll develop autism and the answer we’re getting is that one factor may be prenatal testosterone research on this subject is still in the early stages and experts are still trying to find out what role prenatal testosterone plays in determining sexual differentiation in the brain the skewness the McNish there’s no evidence of predetermination in the brain we’re sort of pushed one way or the other by hormonal effects in the early stages of fetal brain development of course but very much development happens later after birth in infancy and beyond when hormones act jointly with a number of external factors in the environments and above all in a child social environments and here Pranjal Mehta has been researching the influence that hormones and social environment have on behavior development

researchers have including my lab have looked at both directions of effects how hormones influence dominance and status related behaviors and how one’s social status and the environment in turn can impact hormone fluctuations in a feedback loop meter also studied how people perceive themselves and how that perception influences their behavior do people consider themselves dominant or passive and what role does testosterone play and so what we found was that testosterone didn’t have a direct effect and competitive decision-making but it really depended on whether they filled out the questionnaire suggesting that they were high or low in dominance so some of our work does suggests that hormones do impact behaviors such as competitive behavior but interestingly and inconsistent with the sort of myth about testosterones direct effects this depends on people’s personality so the way we see ourselves so testosterone influences our personality and in turn our personality influences our level of testosterone high levels of testosterone are said to make men virile and dominant and society either views such men with respect or contempt testosterone also fuels competition among men perhaps it’s no coincidence that this hormone was discovered during the late stages of the Industrial Revolution in the 1850s sharla Edouard Braun circa was one of the first scientists to speculate on the existence of substances that we now know as hormones he also regularly injected himself with a fluid extracted from animal testicles and claimed that this process improved his sexual prowess and physical well-being testosterone has long been associated with masculinity strength and vitality today testosterone replacement therapy has become popular among older men in some advertisements it’s touted as a miracle cure much as Braun Sekhar claimed more than a century ago pharmacies doctors and drug companies make a lot of money selling testosterone preparations sales have increased sharply since 2007 dr. Michelle its Minh is regularly consulted by older men suffering symptoms of exhaustion many warrior testosterone deficiency may be the cause one Centurion zitz Minh tests the patient’s sperm count and bone density among other procedures in most cases he’s not able to attribute the symptoms to reduce levels of testosterone using bad seeing this graphic shows the testosterone levels of 10,000 men ranging in age from 4 to 90 the boys of course have very low levels signs intimacy and needs a good test is to only come here and improve it the levels increase during puberty then we see high levels of testosterone right into old age if we rule out disease there are several reasons why testosterone levels may fall in other myosins fairness is to say in the vast majority of cases these patients produce less testosterone simply because they’re overweight Gupta’s obesity is a problem for many older men and younger men too for that matter overweight men usually have a lot of visceral fat and that fat releases a number of harmful substances and it can lead to insulin resistance high blood pressure and lower testosterone levels to be good thing one layer of body fat lies just beneath the skin a second layer visceral fat is stored in the abdominal cavity near several vital organs excess visceral fat can cut testosterone production which can promote the storage of even more fat in the abdominal cavity this causes the spare tire that’s common among middle-aged men testosterone is often associated with doping scandals and competitive sports Michale Kleber with the German Olympic sports Confederation is an expert on the use of performance-enhancing substances

including testosterone testosterone plays a key role in regulating muscle mass and how the body responds to exercise during prolonged physical activity the muscles suffer minor trauma so afterwards the body starts repairing the damaged muscular tissue and increasing its strength and size until recently only professional athletes use performance-enhancing drugs now amateur athletes are taking them as well use of testosterone derivatives called anabolic steroids at commercial fitness studios is a huge problem right now we believe that 13 to 16 percent of all clients have used doping preparations mostly anabolic steroids it’s a lot more widespread among amateur athletes than it is among the professionals healthy males produce four to eight milligrams of testosterone every day but for those who are trying to increase muscle mass and performance that amount is too little Christian Wulff tried using testosterone supplements to counter his hormone deficiency skip Sophia product in danger supplement new sweetie now you can find testosterone boosters and capsules I knew that they weren’t going to work but I tried them anyway companies that make these products play on your emotions that’s why I bought them and of course they didn’t help at all Niska but but only anabolic steroids synthetic versions of testosterone can produce the kinds of results that the athletes want the use of steroids to enhance moments is widespread among bodybuilders of my night unfortunate Sabha and Habash not complete in my own research I came across the case of a 17 year old who was using these substances he was scary he was injecting more than a thousand milligrams of testosterone derivatives a week he was also taking Dianabol steroid tablets every day so in all that’s a lot more than a thousand milligrams a week that’s a dangerous amount for a 17 year old it’s a neon escaping the abuse of anabolic steroids can have a number of dangerous side effects including high blood pressure strokes heart attacks and liver damage excessive increases in testosterone can lead to reductions in sperm production because the brain determines that the body has enough testosterone and cuts off the supply Pranjal Mehta has been studying whether substances besides testosterone can influence human behavior for example cortisol a hormone that’s often released in response to stress and low concentrations of blood sugar there are some evidence that cortisol levels could impact the pathway between testosterone and behavioral outcomes specifically hormones don’t influence behavior directly but there’s a mechanism through which they occur specifically one mechanism is they bind to a receptor for that specific hormone in the case of testosterone that would be the androgen receptor this binding process takes place throughout the body like a key fitting into a lock Mirta believes that in stressful situations cortisol blocks the testosterone receptors if cortisol levels are high that could actually antagonize or or impede the relationship between testosterone and behavior presumably through molecular pathways such as receptor reduction and so we theorized what we called the dual hormone hypothesis this role-playing exercise is designed to test the effect of cortisol on testosterone one participant gives a series of orders to the other if the player who’s supposed to follow the orders feel stressed his behavior changes we found that when levels of cortisol were low that effect occurred that higher testosterone was related to more dominance but when cortisol levels are high that effect wasn’t there higher testosterone was not related to more

dominance so this is suggesting that testosterones effects on dominant behavior in a position of leadership really depends on what’s happening in the stress axis in the body so is it possible that testosterone is just one of many substances that can influence human behavior more research on this subject needs to be done at this point experts have come to a variety of different conclusions biology does not mean simplicity I think it’s recognizing and appreciating the complexity that’s we are human beings we’re dynamic systems we’ve developed and evolved to adapt to different environments and that hormones actually their beauty again is that they are responsive to the environment so your hormones affect the way you behave but then the environment also affects your hormone release in general testosterone represents two of the major societal themes of our time competition and success the cliche is that men who have too little testosterone are losers men who have a lot of it are winners invited me which table starts ends I don’t know whether I should be proud of how much testosterone I have or not it depends on what society thinks or desirable qualities in men and that concept can change depending on the culture and the era 13% testosterone is the stuff that men are made of the actual quantity is not so important but every man needs at least a minimum amount since I started testosterone replacement therapy I felt a lot better the depression and lack of energy disappeared in two weeks and things just kept getting better for me I’m not confused and unhappy anymore so there’s no simple one-to-one link between testosterone and male aggression or quest for power latest findings indicate it’s social and cultural environment factors that determine testosterones effects on manly behavior you