November 4, 2021 11:00 am

Erectile Disfunction (ED) happens because of low blood flow from the body to the penis and/or the blood can not be trapped in the penis during an erection (venous leak). We will review from Episode 1 what happens when you have an erection, and then we will discuss the systems that break down that cause ED.

Table of Contents

Overview of Low Blood Flow Causes

In this episode, I will teach you how decreased blood flow causes ED and other causes for ED, such as smoking, alcohol, marijuana, obesity, and others, and some you may not even know about. Since erection depends on the blood vessels that serve the penis, it's not surprising that vascular disease is the leading cause of ED. There are multiple ways to have trouble to develop in the course of an erection. The most common type of vascular disease is atherosclerosis, which occurs when fatty deposit build up on artery walls and narrowing and clogging them.

Imagine a pipe that is clogged up with hair and debris that prevents water to flow through the pipe. The restriction in blood flow can restrict the erection to occur and especially in the artery that supply the blood to the penis. High blood pressure, high cholesterol, diabetes, smoking, all contribute to this condition such as atherosclerosis. This blockage starts in the arteries like the aorta in the abdomen which supplies the blood flow to the pelvis and the penis. If you have a blockage in the aorta like abdominal aortic aneurysm, or triple A, the nerves and the arteries to the penis lie below the aorta. So an aneurysm or Triple A can decrease the blood flow to the penis. This is called proximal blockage, resulting in low blood flow. This is one of the reasons why ED medications such as Viagra or Cialis do not work as a treatment for ED, because they do not address the cause of the blockage or the venous leak.

Where to follow and subscribe

Now venous leak is where blood seeps out of the veins in the penis during an erection, instead of being trapped inside. As a result, a man can get an erection, but he cannot sustain it. If the veins do not constrict enough, blood will leak back into the body, softening the erection. Many men with this type of ED find that they can get a firm erection at first, but gradually lose firmness. And in fact, venous leak is probably one of the most common cause of ED. Venous leak is often in younger men. Several factors can contribute to the venous leak and ED. Vascular disease such as affecting the blood vessels, radiation therapy for cancer treatment, diabetes, Peyronie's disease, nerve disorders, and anxiety. Falls, traffic accidents, and even trauma can damage the artery vein and nerve that produce and sustain an erection. Example is the pelvic fracture.

Lifestyle Factors

Man sitting on coach with laptop - low blood flood cause
Photographer: Windows | Source: Unsplash

A 2020 study in JAMA Neurology found an intriguing link between a history of concussion and formal professional football players and ED. The more symptoms of concussion reported by the players, the more likely they were to receive medication for ED later on in life. Even prolong exercising on a rowing machine or bicycling on a seat that's too hard can cause ED by injuring some of the nerves or artery in around a penis. Now I would talk about bicycling and ED and treatment for this in the next few episodes. Diabetes can cause ED in at least two ways. It can harm the nerve that tells the arteries in the penis to open. And it can also restrict blood flow by damaging the blood vessel. People with diabetes often have high blood pressure and high cholesterol, which then compound the condition that impaired blood flow. Men with diabetes are four times more at risk to have ED.

The ED usually develops gradually and may not be as rigid and cannot be sustained. Sometimes ED is the first sign that a man has diabetes. The worse the blood sugar control, the worse the ED. Let's talk about hormones. Testosterone helps spark sexual interest or libido. You might think that low level of the testosterone hormone can contribute to ED. Low testosterone can indeed play a role, but there is no simple correlation between low testosterone and ED. Some men with low testosterone level have ED, but others do not. Nor does testosterone therapy necessarily solve the problem in those who have ED. A study based on data from the Massachusetts Male Aging Study point to a complex relationship between erectile function and sex hormone. In an analysis of the test drawn from 625 men, ED was not associated with below normal levels of testosterone.

Hormonal Imbalances

man looking over shoulder - low blood flow
Photographer: Oliver Ragfelt | Source: Unsplash

Hypogonadism is the most common cause of ED. This means that testosterone produced by the body, mainly 90% in the testicles and about 10% in the adrenals, fall below the normal range, which is below 300 nanogram per deciliter or free testosterone of five nanogram per deciliter. Usually the total is being measured because total testosterone, which is bound to a protein called sex hormone binding protein, is more stable throughout the day than the free. But I usually order both. The bottom line is, men with possible symptoms of androgen deficiency or testosterone deficiency can actually discuss it with their doctor and request a blood test to measure the testosterone level. But even if your level is low, treatment with supplemental testosterone won't necessarily restore erectile function. Although your libido will get a boost as well as getting more energy, focus, and more muscle definition with testosterone supplementation. Even thyroid, low or high, can affect ED by disrupting testosterone balance. Being overweight, no exercise, such as sedentary activity, poor diet, contribute to ED.

Lack of Exercise and Poor Diet

overflowing hamburger - low blood flow cause
Photographer: Jonathan Borba | Source: Unsplash

80% of men with ED are overweight or obese, have BMI of over 30. And the belly is a risk factor for ED. Having a 42 inch waist is more likely to have ED than men with 32 inch waist. In a study in the Journal of Sexual Medicine, the results show that men who exercise less than the recommended 150 minutes a week were 40 to 60% more likely to experience ED than more active men. So how much exercise is good? In a study in the Journal of Sexual Medicine shows two hours of strenuous exercise, such as running six miles per hour or fast swimming, or three and a half hours of moderate intensity exercise, such as dancing or double tennis, or six hours of light exercise, such as walking. Poor diet with processed food, simple carbohydrate, fried food, cause weight gain and heart disease. A Mediterranean diet is recommended.

It is a diet high in vegetables, fruit, legume, nuts, beans, cereal, multi-grain bread, fish, and unsaturated fat such as olive oil. It usually includes a low intake of meat and dairy food. It is high in antioxidant, omega three fatty acid, which can fight inflammation and keep blood vessel healthy. Smoking. The more cigarette you smoke, the higher your risk of ED. Smokers are 50% more likely to develop ED. Smoking can directly interfere with the nitric oxide signaling system that produces an erection. And of course smoking damage your arteries. Heavy smoking or smoking more than 20 cigarettes a day causes severe ED that happen and unfortunately may not be reversible following smoking cessation. Possibly because the damage already occurred to the delicate blood vessel at that time resulting in low blood flow. However, there is some good news.

Recreational Stimulants

man smoking outside bar - low blood flow
Photographer: Jay Clark | Source: Unsplash

Smoking, excessive alcohol, prolonged use of marijuana can contribute to ED.


There is some mounting evidence that some damage is reversible if smoking is stopped prior to middle age and is not restarted. So how much is bad for smoking? A 29 pack history per year is responsible for significant increased risk for ED compared to someone who smoked like 12 pack year history. And this carries the same risk factor as for a non-smoker. Alcohol and substance abuse. Light to moderate drinker, or men who average one to two drinks a day, are 33% less likely to have ED than non drinkers. According to a Harvard health professional follow up study, heavy drinking can make ED worse.

For one thing, alcohol can inhibit sexual reflexes by dulling the central nervous system or the brain. Drinking large amount of alcohol over a long period of time can also damage the liver, leading to a hormonal imbalance. In this case, raising the level of estrogen, alcohol cause a dehydration, which then decrease blood volume and increase angiotensin release, a hormone that is associated with ED. Long term alcohol abuse can actually cause damage to the nervous system, which is responsible for triggering the signal that cause an erection. Study have also shown that prolonged alcohol abuse can cause irreversible damage to the nerve to the penis.


Alcohol can affect orgasm, ejaculation and also can decrease testosterone. So drinking two drinks a day does not contribute to ED. Illegal drugs, such as marijuana, cocaine, heroin, barbiturate, and amphetamine can trigger problem by acting on the central nervous system or the brain. Some men find that their sexual performance improve when they use marijuana. For instance, if men become less anxious, they may have better ejaculatory control. However other men experience sexual problems with marijuana, such as the following, like low desire. Marijuana can cause men to lose their motivation for sex. For a firm erection to occur, the smooth muscle tissue in the penis need to relax to mitigate low blood flow. However, if THC is combined with CBD receptor in the penis, this process become disrupted. Also, marijuana can make men too relax to have a firm erection. Studies have shown that men who use marijuana regularly are more likely to have trouble reaching orgasm.


Marijuana can increase a man's level of dopamine. It's a neurotransmitter that's associated with pleasure and reward. It may also heighten anxiety. Both of these situations can result in premature ejaculation. The extent to which marijuana impair a man's sexual function can depend on the dose and frequency of use. Men who use higher dose or use it more frequently are more likely to develop sexual problem than those who use marijuana only occasionally. Also, some people are more sensitive to marijuana effect than others. In the next episode, I will talk about treatments of ED, so stay tuned for the next episode.

Wrap Up

Thanks for listening. Be sure to go to my website at for more resources. And remember to join my men's club at, a place where I help a community of men regain their sexual confidence.

And if you like the show, I would appreciate it if you subscribe, leave a review on Apple Podcast or wherever you listen. And know that you have sexual vitality for life. Until next time, this is Dr. Anne signing off.

{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}