START HERE: Porn-Induced Sexual Dysfunction

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 "I think it's safe to say my libido is back, but it was eight weeks of no porn, masturbation or erotica, and minimal fantasy." —Recovered user 

If you are a heavy porn user and you have noticed erectile dysfunction increasing, there may be a connection between the two. See Scientists: Too Much Internet Porn May Cause Impotence (or this article, this article, this article, this article, or this one), or "The Dr. Oz Show addresses Porn-induced ED"

Since writing our first few articles on porn-induced ED, we have seen two common patterns of recovery:

1) A few men bounce back in a relatively short time: about 2-3 weeks. Perhaps their ED is due to psychological conditioning, a very high levels of masturbation (fueled by porn), or low-level addiction related brain changes.

2) The vast majority of guys we encounter need 2-6 months (or longer) to fully recover. Most "long-rebooters" experience a variety of withdrawal symptoms, including the dreaded flatline. It's clear this group has experienced addiction-related changes that reduce stimulation of the brains erection centers. Sexual conditioning plays a significant role, especially with young guys who started early on Internet porn.

Many men cannot believe that Internet porn has caused their ED—until they stop using it, and recover completely. Instead, men tend to assume their ED with a sexual partner is caused by anxiety, low testosterone, the fact the person is not their "type," or lifestyle factors such as smoking or poor diet. If you are under 40, and not on specific medications, and don't have a serious medical condition, the causes of your copulatory ED are almost certainly anxiety or Internet porn—or a combination of the two.

Wondering if your problem is porn-related?

The first bit of advice is to see a good urologist and rule out any medical abnormality. If you have done so, try this simple test to compare and contrast porn-induced ED from performance anxiety induced ED:

1. On one occasion masturbate to your favorite porn (or simply remember what it was like).
2. On another masturbate with no porn/porn fantasy. Masturbate only sensations, with the same speed and pressure you would use during intercourse.

Compare one and two: quality of your erection, the time it took to ejaculate (if you can). A healthy young man should have no trouble attaining a full erection and masturbating to orgasm without porn or porn fantasy.

• If you have a strong erection on #1, but erectile dysfunction on #2, then you have porn-induced ED.

• If #2 is strong and solid, but you have trouble with a real partner, then you have anxiety-induced ED
• If you have problems during both 1 & 2, you may have progressive porn-induced ED, or an organic problem. When in doubt, see a good urologist.

The above test is helpful to differentiate porn-induced ED from performance anxiety: you cannot have anxiety with your own hand. However, it cannot always differentiate between organic ED (hormonal, structural) and severe porn-induced ED - as many men with porn-induced ED cannot maintain an erection even with porn. This test cannot assess if your ED arises from severe psychological issues such as clinical depression. Nor is the above test is not meant to assess whether you have recovered from porn-induced ED or not (see How do I know when I'm back to normal?).

Other symptoms that may be associated with porn-induced brain changes:

• Difficulty reaching orgasm with a partner (delayed ejaculation)
• Experiencing greater sexual excitement with porn than with a partner
• Decreasing sensitivity of penis
• Ejaculating when you are only partly erect, or getting totally erect only as you come
• Needing to fantasize to maintain erection or interest with sexual partner
• Earlier genres of porn are no longer "exciting"
• Declining sexual arousal with a sexual partner(s)
• Losing erection while attempting penetration
• Can't maintain erection or ejaculate with oral sex

Internet porn causes ED, not "excessive masturbation" or "sexual exhaustion"

Really get this: Internet porn (or rather its constant novelty) is the cause of ED - not ejaculation or "sexual exhaustion". I've never heard of masturbation causing chronic ED in healthy young men, unless one employs a serious "death grip" or traumatic masturbation techniques. Another myth is that masturbation or orgasm depletes or lowers testosterone leading to "sexual exhaustion." Porn-induced ED has absolutely nothing to do with blood testosterone levels. (See: Any connection between orgasm, masturbation, and testosterone levels?)

On the other hand, it's possible that masturbation and orgasm could play an indirect role in porn-induced ED. Frequent ejaculation in animals leads to several brain changes that inhibit dopamine, and thus libido, for several days. Under normal circumstances, sexual satiety (defined differently for each species) leads to males taking a time out from sexual activity. Sexually satiated porn users may override these inhibitory mechanisms by escalating to extreme porn, or spending more time watching. Both goose dopamine. Pushing past "I'm done" signals may lead to the accumulation of DeltaFosB. Without the lure of Internet porn, how many guys would just give it a rest? For more see: Does Frequent Ejaculation Cause A Hangover?

How different is Internet porn of today from porn of the past? We know of a healthy young man who did not masturbate, but developed ED by just watching Internet porn. His schedule was to watch porn every day, but to masturbate only once every ten days. Others have developed ED by edging to porn, while only orgasming every few months.

Internet porn, with or without penile stimulation, keeps dopamine surging. Continued porn use, not masturbation, is what causes tolerance and escalation to more stimulating genres. Porn is what allows you to override your natural sexual satiation mechanisms and continue to masturbate or edge.

One guy comparing himself to his buddy:

My friend masturbates like 10-15 times a day. Not even exaggerating. He seriously has an addiction, but he thinks its normal. He also doesn't have Internet access, so he never really gets to watch porn either. And he's never had a problem keeping it up in bed. On the other hand, I can't remember the last time I masturbated without looking at porn. But I might masturbate only 4-5 times a week on average. And I have tremendous issues staying hard. At first I thought it was nerves, but after getting more acclimated with sex, I actually found sex to be tiring and boring. Unless the girl was deepthroating me and telling me to choke her, I don't really find sex to be all that great. I'm very desensitized to the female anatomy.

Strictly speaking, you don't have to be watching porn to develop ED:

I know with me I think I got so used to being almost hypnotized by girls online and masturbation, that real girls that I had to interact with in bed just threw me off and I couldn't perform. I'm not even talking about porn, I don't use porn but still look at clothed pictures of women online. Like a lot of other people here, I have relapsed plenty of times. I personally think it DOES have to be all or nothing, no 'little bit here and there.' You may not relapse if you start looking at girls online again, but I'm sure it slows down your reboot. I thought the same thing, that if I look just a little bit every once in awhile it would cumulatively fix me, it didn't.

In the last 20 years, I used to masturbate an average of more than once a day. I was never into porn. And yet, I experience all the symptoms that you guys do.

What's happening in the brain for chronic ED?

Since no one appears willing to study this rapidly emerging phenomenon, we can only guess. I think it's caused by a combination of factors. Real sex is touching, being touched, smells, pheromones, connecting and interacting with a person. Internet porn is 2D voyeurism, clicking a mouse, searching, multiple tabs, while only interacting with your hand. To use a sports analogy, what event has your brain been training for? Besides addiction-related brain changes, years of Internet porn can create a mismatch between what your brain expects, and what it actually happens during real sex.

I suspect that a combination of the following leads to porn-induced sexual dysfunction:

1. Reward circuitry desensitization (an addiction process),
2. Brain rewiring or sensitization to Internet porn. In essence, it's wiring (or rewiring) ones sex response
   to 2D screens and voyeurism. Watch Adolescent Brain Meets Highspeed Internet Porn and listen to these radio shows to understand rewiring & escalation: Porn, escalation, tolerance and morphing sexual tastes (show #16) and Porn, sexual conditioning and the adolescent brain (show #17). Rewiring can manifest as escalation to genres that don't match your original sexual tastes. Wiring to Internet porn before wiring to real partners (men who started early with porn) is a major factor in long reboots for young guys.
3. Desensitization of the hypothalamus sexual centers (which does not occur in other addictions and may be a key to recovery)
4. Conditioning to a certain level of visual & auditory stimuli, and the rapid fire delivery system (Pavlovian, rewiring, addiction process)
5. Death grip and rapid jerking (multiple levels of nervous system adaptation),
6. Psychological aspects of using Internet porn (hard to quantify)

• Our most complete science-based article on porn-induced sexual dysfunction - Why Do I Find Porn More Exciting Than A Partner?
• A recent study found that "psychogenic ED" is strongly associated with atrophy of the reward center (nucleus accumbens) and the male sexual centers of the hypothalamus (as described in my porn & ED presentation): Macrostructural alterations of subcortical grey matter in psychogenic erectile dysfunction (2012)

Other Psychology Today posts which address this phenomenon:

• Porn-Induced Sexual Dysfunction Is A Growing Problem
• Are Porn Tube Sites Causing Erectile Dysfunction?
• As Porn Goes Up, Performance Goes Down?
• How I Recovered from Porn-related Erectile Dysfunction

Both sexual desire and erections run on dopamine from the brain's reward circuitry. The dopamine-producing nerve cells in the reward circuitry activate the sexual (libido) centers of the hypothalamus, which in turn activate the erection centers in the spinal cord, which send nerve impulses to the genitalia.

Logic dictates that desensitization (decline in dopamine signaling) of the reward circuit has occurred in men with porn-induced ED. Just as important is the process of sensitization, which is formation of Pavlovian addiction pathways for Internet porn. Desensitization is a general dialing down for all pleasure seeking activities, while sensitization ramps up the reward circuit for only one stimulus - your addiction.

Although all rewards intertwine into overlapping circuits, each natural reward (food, water, love & sex) has its own devoted micro-circuits. With porn-induced ED, I suspect that male sexual centers (hypothalamus) and limbic circuits devoted to sexuality are also affected. Erections require adequate dopamine in the reward circuit and the male sexual centers. Is it possible that years of overstimulation down-regulates dopamine signalling and rewires innate sexual circuits? ED in healthy young men, which takes months to reverse, suggests this is likely.

What is understandably confusing is that guys can get an itch to masturbate while they are experiencing erectile problems. The urge to jerk off is similar as the urge to eat junk food when you are obese. It's an addiction response to 1) reduced dopamine signaling which leaves you unsatisfied, plus 2) sensitized addiction pathways bombarding the reward circuit with "do it" messages. In a guy with porn-induced ED, this buzzing of your reward circuit isn't true libido, it's a cue-induced 'drug' craving.

To develop porn-induced ED, heavy porn users have spent years overriding their normal mechanisms. Once porn users with ED stop, they all experience a period of no libido and “dead dick.” They are now experiencing their true libido, minus the 'drug.' For years, they have simply ignored their true libido (when it signaled, "Enough!"). The urge to use was an urge triggered by cues of their addiction.

Is an obese person who finished a large meal 2 hours ago truly hungry? No. Would a severely overweight person eat as many calories if she had only a hunter-gather diet of wild game, nuts and occasional berries? Of course not. When porn users remove the superstimulus (Internet porn) they discover their true libido, which then gradually returns to normal.

For first-hand accounts of erectile dysfunction recovery, see the links here. Also see these Rebooting Accounts as they describe the recovery process, including ED. Here's the "Benefits" PDF document from which we took these. We update it periodically.

And here's a pep talk from a guy who recovered to another guy who, 15 days into recovery, had "absolutely no sex drive or erections":

This is normal. Hang in there. You probably are getting night erections (and morning erections) you just don't realise. If you wake up to an alarm, try waking up naturally. This will make sure you wake up just after the REM cycle and you'll still have your nocturnal wood. This might restore some faith in your penis. Best thing you can do though is give it time. Your body is amazingly adaptable and will restore balance eventually.

What do guys who successfully recover suggest?

The good news is that the situation is likely to be reversible. The bad news is that you will have to overcome your compulsive use of porn, because it is desensitizing a primitive part of your brain, numbing it to pleasure so it needs increasingly intense stimulation. From all reports, the fastest and easiest recovery path is elimination of all artificial sexual stimulation, including porn fantasy, chat rooms and erotic stories. 

More bad news is that during the recovery phase most guys need to eliminate, or drastically reduce, masturbation and orgasms. Logic indicates that you need only eliminate porn to regain erectile health. However, experience tells a different story. Nearly all of the men who recovered from porn-induced ED eliminated masturbation and drastically reduced frequency of orgasms (even with a partner).

Think of it this way - if you have Porn-induced ED, your brain is saying: "I can't do this anymore". Understand that your urge to masturbate is not true libido - you are addicted. If you need porn to masturbate, or have a partially erect penis when you do, you are not horny or in need of "release". You are addicted and in need of a temporary dopamine high.

Those who continue to regularly masturbate and orgasm during their recovery tend to become frustrated at their lack of progress, and we never hear from them again. Since we have very little data on those who continue to orgasm, we can only report the success stories we have. However, a few men continue to have orgasms with a partner and make decent progress. What makes these guys different? Nearly all started late on Internet porn and had a steady diet of sex or masturbation to fantasy for years before Internet porn. For example:

I'm married, like you. I gave up the P and the M...but not the O's with my lovely wife. We had regular sex throughout my reboot. I still healed just fine. I no longer suffer from ED or PE at all, and my sex life is getting better all the time.

I'd never say my way is the only way. I just know it worked for me. And I ALSO think that I might have healed faster if I had abstained from the O's with my woman for a while...though I will never be sure. In my mind, it was a tradeoff I was willing to make. And it worked out well.

Why must you drastically reduce orgasms and masturbation to recover? Sometimes healing involves more than just removing the original cause of the problem. If you break your leg in three places, it takes more to heal than simply avoiding further accidents. You need to cast, immobilize, and not put stress on that leg until the bone is strong. Sexual contact is great, but ejaculation and staying close to the edge of ejaculation can slow your progress.

And when the leg starts to feel better you don't test it by playing tackle football. In other words, having several orgasms in a row, following months of rebooting, may set you back. Ease into ejaculation. Although you may be functioning OK, most guys report continued progress for months. Continued healing is the norm. 

As stated, sexual stimulation with a partner can be a good thing, although orgasm can cause cravings, and seems to slow ED recovery. In fact, fooling around with your partner is great as it wires you to the real deal. Some guys suggest gentle intercourse with no ejaculation, while others mix in ejaculation. If you have ED and decide to regularly orgasm, do no compare yourself to rebooting accounts where guys abstained from orgasm.

If you are trying to reboot and have a partner see the following FAQs:

• Rebooting with a partner
• "What do I tell my girlfriend?"

Why guys drastically reduce masturbation & ejaculation during a reboot:

1. It seems to precipitate a more complete and deeper withdrawal, and thus healing.
2. Masturbation and porn use are tightly wired together. Like Pavlov's dog that salivated when it heard the bell, you will start drooling for porn when masturbating. Time is needed to weaken the neural connections intertwining wanking and watching.
3. Recovery is sometimes easier without masturbation/orgasm. With masturbation/orgasm removed from the equation, most guys experience a sharp decline in sexual desire, we call the "flatline". The flatline/dead dick phase is strong evidence that eliminating orgasm is qualitatively different from just eliminating porn.
4. Masturbation and orgasm strongly reactivate cravings to use porn. It's surprising to witness that most men have an easier time eliminating masturbation than they do porn. For most guys who visit, masturbation is simply not that interesting without porn, and they are amazed to discover that porn, not their libido, was driving their constant search for relief.

• Caveat: All the above is based on the current feedback given to us by successful rebooters. It is subject to change.
• Caveat 2: Some guys with porn-induced ED need to eventually orgasm in order to jump-start their brains after a reboot or extended flatline

Remember, reducing or eliminating ejaculation is only temporary.

YBOP is NOT an anti-masturbation website. I need to shout this, because I've read this nonsense on many forums, where discussions over Internet porn causing ED quickly devolve into pro/con masturbation debates. The name of the site is your brain on porn. Confusion occurs because: 1) this generation sees masturbation and porn use as synonymous, 2) men who recover from ED do so by also eliminating masturbation/orgasm. It's real simple: few men heal porn-induced ED while continuing on a regular masturbation schedule. We do not advocate abstinence as a permanent lifestyle.

The last thing you want to do is to become so "anal" that you never attempt to give up porn.  Check out this thread on The Orgasm Reboot, and this thread on a cult being developed around masturbation being unhealthy. The take away from both threads is that guys quit trying because they think they believe that rebooting is all or none. This is complete nonsense. If you fall back into porn use, you have not lost all your gains. Simply the process again.

Bottom line:

• Eliminate all artificial sexual stimuli: porn, chat rooms, erotic stories, surfing for pictures, etc.
• Contact with another person, even sexual intercourse, can be quite beneficial.
• Orgasms can slow the process.
• There comes a point in the process where you need to rewire to real partners or consider masturbation

The process

The return to full erectile health can take 2 - 6 months or longer, so be patient. Men report continued improvement after their initial reboot. Please be aware that a pattern is emerging: Young men who have been using Internet porn since they began masturbating are requiring a longer recovery period.

• Young Porn Users Need Longer To Recover Their Mojo
• Started on Internet porn and my reboot (ED) is taking too long.

In other words, older men who spent years climaxing before introducing Internet porn recover faster. The older men used their imaginations to wire to real girls, whereas, younger guys have spent years wiring to computer screens and heaven-knows-what. This is a generalization, , but it can take time. But waiting and waiting may not be enough. In order to heal, some young guys may need to rewire their sexual circuits to flesh & blood humans.

One guy explained:

Escalation into extreme genres is not a prerequisite for porn-induced ED. While watching a genre of porn that is very different from what you do in your actual sexual encounters may be a reason for developing ED with real woman, an even more common reason is that you'r wiring yourself to sexual voyeurism.

Real sex is usually very different from any genre of porn. In real sex you don't see the whole body all of the time and can't always focus on your prefered body part. Sometimes you're so close you can only see her face. You have to rely a lot more on touch, smells and the physical stimulation of your penis. Also, you have to work a lot harder; you have to change positions, use your whole body, etc. Another HUGE difference is, that you can't skip forward to your favorite scene all the time, and can't change to a clip with hotter women at your convenience. All of the above can contribute to ED with real women, even if you don't watch extreme porn. But of course it's not necessary; not all who smoke get cancer.

Said one guy:

I am in my late 30's, have used porn heavily since my teens, and have had ED problems for a long time - at least since my late 20's, though it's only recently that it's become almost total copulatory ED. I've blamed it on partners ("I'm just not attracted to you"/"I wish you were more responsive"), the newness of partners ("I need to give my body time to catch up to my brain"), fitness levels, diet, age, stress, performance anxiety... And actually, all of those, except for the "I'm just not into you" factor, probably have a part to play. But when I realized I could no longer even masturbate to orgasm without porn - something clicked. It seems blindingly obvious now, of course.

Like a lot of men, I imagine, I went to a doctor, got a physical that ruled out any serious medical conditions, and got a Viagra prescription.

Lack of desire was one factor in the failure of my marriage, and the failure of a relationship subsequent to that. (That whole dynamic added another factor/excuse - "I'm still getting over the split from my ex.") And of course once my marriage failed and I was single again - porn use went into overdrive, at least once a day and often two or three times. I'm now with a new partner who I am very attracted to and with whom I am very comfortable sexually - but I still cannot perform. Thankfully she is open to frank discussions about this stuff.

I was coming around to the conclusion that I needed to ditch the porn anyway - this article has just confirmed it. It really was like reading something I could have written. So, thank you for that. Not looking forward to 2-3 months of rebooting [no masturbation or porn], though, I must say!

Some men who have experienced a decline in their sexual responsiveness (without realizing its true cause) are afraid that avoiding masturbation and porn will make their libido disappear completely. It may disappear at first. The process of returning to full erectile strength often involves a decline before it gets better. However, as their brains come back into balance, people tend to become more sensitive and sexually responsive, not less. People also notice that little things turn them on, such as a mere smile from a real woman.

The problem isn't in your penis, so Viagra won't stop the deterioration even if it can temporarily mask the problem. You need to reboot your brain (that is, return your sensitivity to the neurotransmitter dopamine to normal). For a psychiatrist's explanation of what's going on, here's an excerpt from The Brain That Changes Itself by psychiatrist Norman Doidge.

During the mid- to late 1990s, when the Internet was growing rapidly and pornography was exploding on it, I treated or assessed a number of men who all had essentially the same story. ... They reported increasing difficulty in being turned on by their actual sexual partners, spouses or girlfriends, though they still considered them objectively attractive. When I asked if this phenomenon had any relationship to viewing pornography, they answered that it initially helped them get more excited during sex but over time had the opposite effect. Now, instead of using their senses to enjoy being in bed, in the present, with their partners, lovemaking increasingly required them to fantasize that they were part of a porn script.

What's normal?

Porn-related erectile dysfunction, copulatory impotence (can get erect with today's porn, but not with partner) and delayed ejaculation are becoming more and more common, probably due to the extreme stimulation of the brain inherent in Internet porn. (See: He’s Just Not That Into Anyone.) Yet these conditions are certainly not "normal" in young men.

Here are signs that you are coming back to normal. Said one guy,

I think a sign that your equipment will start to work right, is when you start to wake up with morning wood. If not full wood, at least half-wood is a good start. I also believe that when you see sexual images or semi-sexual images of folks on TV, and you feel tinglings in your brain, that's a sign you are starting to re-sensitize yourself to normal.

Please note: People here often recover their erectile health and can have healthy sex with a partner. However, recovery does not mean you will be able to go back to using porn without desensitizing your brain anew. As one forum member said:

My story began with porn-related ED: going soft inside a woman or after changing positions. Once I hit 3-4 weeks, my morning and random erections became very hard and frequent. I thought I must "test" myself to make sure everything is working. Trust me when I say, "There is no need to test; it is indeed working." I tested myself and ended up relapsing. First it was MO, then PMO... then the vicious cycle began all over again.

What I say to doubters:

First, the head of the Italian Society of Andrology and Sexual Medicine (SIAMS) has warned that porn-induced ED exists. SIAMS, the largest urology organization in Italy, is the one and ONLY group of medical doctors to address this emerging phenomenon. More important, their president reports that the clinic he's part of cures the disorder by having guys stop porn use for 2-3 months. We were writing articles on porn-induced ED before SIAMS statements went public.

Second, naysayers suggest that we need "peer-reviewed studies" to confirm the existence of porn-related ED before we can make any claims. However, it's painfully obvious that no researcher can conduct a study where one group of young healthy men use Internet porn for 10 years, and a comparable control group does not, with erectile function assessed through masturbation to sensation only (no porn). In other words, it may be that the only experiment possible is well under way - with thousands of results reported.

THE EXPERIMENT - "UNEXPLAINED CHRONIC ED IN YOUNG MEN AND ALTERATION OF A SINGLE VARIABLE"

This ongoing experiment examining porn-induced ED is valid, reproducible, and empirical.

The Subjects:

1. Thousands of otherwise healthy young men (early 20s at the moment...), with only one variable in common: Years of masturbation to Internet porn.
2. The subjects differ in backgrounds, ethnicity, diets, exercise regimens, religious beliefs, moral beliefs, country of origin, education, economic status, on & on.
3. These young men cannot achieve an erection without porn use, and gradually, some can no longer achieve an erection with porn use.
4. Many have seen multiple health-care practitioners and all have tried a number of approaches to cure their copulatory ED with no results.
5. Most state that they cannot believe that porn use could have caused ED. Some are very skeptical prior to starting their experiment of giving up masturbation to porn.
6. The cause of their ED was not performance anxiety as they failed to achieve full erections while attempting to masturbate without porn (How do I know if my ED is porn-related? (TEST)

The regimen:

1. All eliminate porn use.
2. Most (but not all) eliminate, or drastically reduce, the frequency of orgasms.

The results:

Nearly every subject reports a similar constellation of physical and psychological symptoms when they stop porn use/masturbation, a similar time-frame for the appearance of symptoms such as agitation, cravings, complete loss of libido, gradual recovery, and need 2-6 months (or longer) to regain erectile function. This suggests a very specific set of physical brain changes, and not a psychological "issue." The usual pattern of recovery is as follows:

1. Subjects experience varying withdrawal symptoms that parallel drug/alcohol withdrawal, such as cravings, anxiety, lethargy, depression, brain fog, sleeping abnormalities, restlessness, agitation, aches, pains, etc.
2. Within 1-2 weeks, most subjects experience what is called "the flatline": low libido, perceived changes in genital sensation or size.
3. The flatline slowly abates and libido gradually increases, morning erections and spontaneous erections often show up, attraction to real partners increases, etc.
4. If the men stick to the regimen, nearly all regain erectile health.
5. Lengths of full recovery vary from a few weeks to several months months. Most are in the 2-6 months range for chronic, longstanding ED.

Summary:

Young healthy men, with unexplained ED and only one variable in common (Internet porn use), attempt multiple regimens and treatments with no success. The subjects remove the one variable they have in common and almost all experience the same results - remission of their medical condition.

That's an experiment with unequivocal results. This is empirical evidence at its best.

Bottom line:

I have yet to see one naysayer address the ACTUAL FACTS as described. In debating the existence of porn-induced ED, doubters go no further than this point:

• Some guys who watch Internet porn develop ED - so - "correlation does not equal causation."

They refuse to venture into the rest of the facts, such as:

1. All subjects had been using porn for years with no problems getting erections.
2. Few report any moral or religious misgivings, or guilt, surrounding their porn use.
3. Subjects experienced a gradual decline is sexual function - often over the course of years.
4. Many subjects had seen medical professionals, and had tried various therapies or regimens - with no success.
5. When they abstained, nearly all subjects experienced similar psychological and physical symptoms - which mimic withdrawal from an addiction.
6. The clincher: All had only one variable in common. When that single variable was removed (masturbation to porn) - nearly all regained erectile health.  (If they did not regain erectile health and libido, the cause of their ED was likely not porn use.)
7. Men who regain erectile health and then return to regular porn use, experience a return of ED - once again settling the issue of causation.