This section will explain what erectile dysfunction is. It will also describe many of the most common factors that cause erectile dysfunction. In addition, this section will shed light on how prevalent erectile dysfunction is in many parts of the world.
Erectile dysfunction (‘ED‘), also known as impotence, is a medical term that describes the inability to achieve and / or maintain a penis adequately erect for sexual intercourse. Erectile dysfunction is different from other conditions that interfere with male sexual intercourse, such as lack of sexual desire or libido, and problems with premature ejaculation.
Most men have at some point experienced problems obtaining or maintaining an erection. This could be due to fatigue, an increase in stress, illness, medication, infection, alcohol, etc. This is normal and not referred to as the condition called erectile dysfunction. Erectile dysfunction is generally manifested if satisfactory sexual intercourse has been impossible during a period of time consisting of several weeks or months.
How Common Is Erectile Dysfunction?
It is difficult to say exactly how common erectile dysfunction is across the world because different cultures have different lifestyles and different environments, and therefore probably also have different levels of erectile dysfunction.
Also, many of the sources for assessing the prevalence of erectile dysfunction are based on self-reported surveys, and not everyone is honest when filling out these surveys. Therefore one may not get a totally accurate picture of erectile dysfunction prevalence.
However, based on the current data, here is information from various studies about how common erectile dysfunction is around the world:
- One study showed that about half of American men over the age of 40 have some degree of erectile dysfunction.
- Another US study demonstrated that at age 40, approximately 40% of men are affected by erectile dysfunction. The rate increases to nearly 70% in men aged 70 years. The prevalence of complete ED increases from 5% to 15% as age increases from 40 to 70 years.
- Another study claimed that ED is a common condition for as many as 30 million men in the United States and over 150 million men worldwide. However, if the figure is 30 million in the United States, and one were to apply the same ratio worldwide, more than 700 million men would be affected by erectile dysfunction.
- Population studies conducted in the Netherlands found that some degree of erectile dysfunction occurred in 20% of men between the ages of 50-54, and in 50% of men between the ages of 70-78.
- An Italian survey reported that about 25% of men seeking medical help with erectile dysfunction were below the age of 40.
- A study in France showed that 32% of all French males had erectile dysfunction to some degree.
- A study of men in Croatia reported the following prevalence of erectile dysfunction:
- 35-39 years: 6%
- 40-49 years: 7%
- 50-59 years: 18%
- 60-69 years: 18%
- 70-79 years: 30%
- One Australian study reported that the rates of erectile dysfunction for different age groups were as follows:
- 20-29 years: 9.2%
- 30-39 years: 8.4%
- 40-49 years: 13.1%
- 50-59 years: 33.5%
- 60-69 years: 51.5%
- 70-79 years: 69.2%
- 80+ years: 76.2%
- In the UK, one study reported that ED in the 20-40 age group affected around 7-8% of men, in the 40-50 age group it affected 11%, in the over-60s age group it affected 40%, and in the over-70s age group it affected more than half of the men.
- Large differences are present in the prevalence of erectile dysfunction between countries. For example, the prevalence of moderate to severe ED at ages 40–70 was reported by one study at 35% in the United States, 39% in Japan, 21% in Italy, 15% in Brazil, and 16% in Malaysia.
- Studies on Japanese men have reported that 26% of Japanese men over the age of 18 had ED, while this ratio was increased to 39% for Japanese men 40-70 years old.
- A study of men in Singapore showed a prevalence of erectile dysfunction in 53% of men aged 40-69 years.
- A study of Taiwanese men above the age of 30, reported that 27% of all participants had erectile dysfunction. The prevalence of erectile dysfunction was 29% of all men above the age of 40 in the study.
- A study of Nigerian men reported that the prevalence of erectile dysfunction was 34% in men aged 40 years and below, and 72% in men above 40 years.
Although these numbers vary quite a bit, it is clear that erectile dysfunction is a relatively common condition that affects a significant number of men, particularly as they age. It has also been predicted that the prevalence of erectile dysfunction is likely to increase as our lifestyles keeps becoming less and less healthy.
Causes Of Erectile Dysfunction
Erectile dysfunction is typically a result of medical, physical or psychological factors, or a combination of two or more of these. However, the underlying problem that causes men to experience erectile dysfunction is typically always impaired blood flow. Let me repeat that: the underlying problem that causes men to experience erectile dysfunction is typically always impaired blood flow. There needs to be enough blood flowing to the penis to fill it and build pressure. If there is inadequate blood flow, the penis will not become engorged. No blood flow or not enough blood flow equals no erection.
Another underlying problem that will cause erectile dysfunction is when the penis is unable to retain the blood that has already entered it. In other words, blood flows to the penis, but it is not contained or trapped in the penis, and therefore flows right back out. This is called venous leak – see below for information about this.
Here are some of the most common factors that cause erectile dysfunction:
- Aging: As we age, our cells become older, are less able to divide, and cells in certain parts of our body stop being replaced by newer cells. Our bones tend to become less dense, muscle tissue starts to decrease in size, blood vessels tend to become stiffer, our DNA structure becomes shorter, etc. In short, the body experiences an overall level of decay.
- High blood pressure: High blood pressure can cause internal damage to the body’s blood vessels by injuring the endothelial cells that line these blood vessels. This may impair the body’s ability to produce nitric oxide, which may directly cause reduced blood flow through the body and to the genitalia. High blood pressure may also lead to atherosclerosis because this higher blood pressure puts added force against the artery walls, which makes these walls attract plaque buildup. Atherosclerosis is a condition where the inner lining of the blood vessels, the endothelium, gets covered in plaque. This build-up will often cause big pieces of plaque to be broken off, causing raptures to blood vessels. Drifting pieces of plaque may also block smaller blood vessels elsewhere in the body. When atherosclerosis becomes advanced, it may make the blood vessels narrower and harder, and it will therefore become more difficult for the blood to flow through them. This process often clogs up the smaller arteries first, such as those in the penis, and will often lead to erectile dysfunction. When arteries become harder and stiffer, they also break and leak more easily.
- Diabetes: Erectile dysfunction tends to develop 10-15 years earlier in diabetic men than in non-diabetic men. Men with diabetes will have higher than normal levels of blood sugar. More blood sugar normally means more superoxide. Superoxide is a free radical that easily reacts with nitric oxide. This typically means less nitric oxide. Diabetic men normally also have greater severity of atherosclerosis than other men, and may as a result experience restricted blood flow in the body and to the genitalia. Diabetes may also cause erectile dysfunction by damaging both sensory and autonomic nerves, a condition called diabetic neuropathy. Many men with diabetes also develop a muscle disease called myopathy. This may cause ED because the muscles in the corpora cavernosa may experience a decreased overall compliance (or put differently, they may stop doing what they are being instructed to do). This may present itself as an inability to obtain and maintain an erection.
- Cardiovascular disease: Cardiovascular disease is a general term that describes a disease of the heart or blood vessels. Very often, cardiovascular disease will mean that the heart is restricted from pumping the desired volumes of blood freely around the body. Anything that leads to impaired blood flow is also likely to at some point, if severe enough, cause erectile dysfunction. Atherosclerosis is one of the most common culprits of cardiovascular disease, and this will often lead to erectile dysfunction before life-threatening consequences typically occur.
- Nerve or spinal cord damage: Back injury from automobile or other accidents, radiation to the prostate, prostate surgery, etc. may damage the nerve system or the spinal cord. When this happens, the pathways of communication from the brain to the penis may be damaged, which may cause the required signals from the brain to not arrive at all, or arrive in a different form. As a result, the ability to obtain and maintain an erection may be impaired.
- Cigarette smoking: Cigarette smoke contains more than 40,000 chemicals, many of which are toxic to the human body. Examples include acetone, ammonia, nicotine, arsenic, lead and tar. Nicotine for example, damages the arteries in two profound ways. Firstly it causes already stored fat deposits in the body to be released into the bloodstream. This fat-blast may stick to the walls of the arteries and thereby clog up these arteries, causing atherosclerosis. Secondly, nicotine causes new blood vessels to form inside the existing blood vessels, called internal vascularization, which further accelerates the narrowing and clogging of the arteries. Introducing a large number of toxic chemicals into the fine-tuned system of the body, is likely to cause a number of complications, including problems with normal erectile functioning.
- Low Testosterone: Testosterone is one of the most important agents in the process of erectile and sexual functioning. It is one of the key building blocks that provide an environment that enables sex and reproduction to happen. A certain level of testosterone is therefore needed to be present in order for a man to function sexually. Low testosterone can be the result of one or more of several factors such as stress, an unhealthy diet, little or no exercise, ageing, lack of sleep etc. To learn more about testosterone on Truelibido, please go here.
- Substance abuse: Substance abuse, which normally entails subjecting the body to one or more toxins, may disrupt the fine-tuned functioning of the body, may cause nerve damage, may lead to atherosclerosis and may lead to reduced testosterone levels. Any of these factors is likely to lead to difficulties obtaining and maintaining an erection.
- Stress: Stress is a mechanism the body puts in place when faced with a situation that is perceived as potentially dangerous. When a body is in a state of stress, it will channel attention to those parts of the body that are critical for the dangerous situation, such as hearing, vision, the heart, muscles needed for a quick escape, etc. At the same time, those parts of the body that are not critical for the dangerous situation, such as the reproductive functions, basically shut down. Therefore, getting an erection while stressed is much more difficult. The body does this by releasing cortisol, adrenaline, norepinephrine, dopamine, etc. into the bloodstream. Excess levels of cortisol will also normally have a negative impact on testosterone levels, because cortisol and testosterone compete for the same space, meaning more of one normally means less of the other. Also, elevated levels of stress over a long period of time put additional strain on the heart and may eventually lead to cardiovascular disease, which in turn may lead to decreased flow of blood in the body and the genitalia. To learn about my experiences with stress, please go here.
- Medications: Many common medications will cause erectile dysfunction as a side effect. This is normally so because they affect a man’s hormones, nerves, increase blood pressure, or weaken blood circulation. These medications are often antihistamines, tranquilizers, appetite suppressants and hypertension medication.
- Cycling: Significant time spent cycling may lead to erectile dysfunction, as sitting on the saddle for long periods of time may cause undue pressure on the nerves and arteries going to the penis. This may weaken the functioning of these nerves and arteries, and a possible outcome is impaired sexual functioning.
- Psychological factors: Psychological factors such as anxiety, guilt, depression, widower syndrome, low self-esteem, post-traumatic stress disorder, fear of sexual failure, indifference, etc., may also be responsible for erectile dysfunction. There are several reasons why a psychological issue could lead to erectile dysfunction, however, in general, a person who suffers from a psychological issue is normally not in an optimal mental state, and will often as a result be pre-occupied with thoughts and mental processes specific to that psychological factor. As a consequence, this person may have difficulties focusing on sexual activity, or may not have a healthy relationship to sexuality.
- Pornography and over-stimulation: When a man very frequently exposes himself to pornography and sexual stimulation, the body will often become desensitized to this. As a consequence, stronger and more extreme forms of pornography and stimulation are generally needed to achieve the same sensations. As more stimulation is supplied, the body then gets further desensitized. When the body becomes significantly de-sensitized, the outcome is often difficulty with obtaining or maintaining an erection. The reason erectile dysfunction may occur as a result of this over-stimulation is because the dopamine reward system in the brain gets exhausted. When this reward system becomes excessively flushed with dopamine, the dopamine receptors will often no longer be able to pick up the dopamine, and as a result, the release of this dopamine will not produce its intended outcome. To learn more about dopamine on Truelibido, please go here. To learn about my experiences with pornography and stimulation, please go here.
- Being out of shape: Excess body fat, or obesity, has several negative effects on the ability to obtain and maintain erections. Firstly, unhealthy foods and lack of exercise that cause weight gain tend to contribute to the narrowing and hardening of arteries, called atherosclerosis, which in turn may have a negative effect on blood flow in the body and to the genitalia. Excess body fat, and particularly belly fat, is also highly correlated with low testosterone. Fat cells contain an enzyme called aromatase and as one’s body weight increases, the levels of this enzyme increase as well. Aromatase converts testosterone to estrogen, which causes the important testosterone / estrogen ratio to be shifted downward. Testosterone is a crucial factor for sexual functions to operate well. Increased amounts of body fat also normally lead to increase in cortisol levels. Cortisol will normally reduce testosterone levels, and hence by adding fat to the body, testosterone gets attacked by several fronts. To learn more about testosterone on Truelibido, please go here, and to learn about my experiences with exercise, please go here.
- Poor diet: The body is a very sophisticated system, and it needs essential nutrients such as fatty acids, amino acids, carbohydrates, vitamins and minerals to operate normally. If we do not consume adequate amounts of these nutrients, our bodies will not be able to function optimally. Essential nutrients are paramount to every organ and process in the body. They are the building blocks of life and without them our cells would not function properly. These essential nutrients are also necessary in order for sexual functions to work optimally. In fact, the ability to get an erection, can be one of the first functions to operate sub-optimally when the body is not in balance. These essential nutrients play a very important role in stimulating sex drive and provide support for the sex hormones. To learn about my experiences with different diets, please go here.
- Lack of sunshine: UVB radiation from the sun enables the skin to produce vitamin D3. Inadequate amounts of sun will normally mean that the body gets inadequate amounts of vitamin D3. Vitamin D3 is important for production of testosterone. So if a person doesn’t get enough sun, it is also likely that he will have inadequate levels of testosterone. To learn about my experiences with sun exposure, please go here.
- Lack of sleep: Sleep deprivation may cause the body to produce less testosterone than it otherwise would have. The body produces most of its testosterone during the night when the body is supposed to sleep. Therefore, if the body is not getting enough sleep, inadequate testosterone production may result, which may in turn lead to erectile dysfunction. To learn about my experiences with sleep, please go here.
- Venous leak: Venous leak is a condition that will normally cause erectile dysfunction. An erection happens when blood flows into the penis and is trapped there, and hence one gets a build-up of pressure and engorgement of the penis. Venous leak describes the situation where the blood is not being retained in the penis, but rather quickly flows back out of the penis. Therefore, even if there is adequate blood flow to the penis, the person is not able to maintain an erection because the blood flows out and away.
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