However, none of the familiar correlative factors suggested for psychogenic ED seem adequate to account for a rapid many-fold increase in youthful sexual difficulties. For example, some researchers hypothesize that rising youthful sexual problems must be the result of unhealthy lifestyles, such as obesity, substance abuse and smoking (factors historically correlated with organic ED). Yet these lifestyle risks have not changed proportionately, or have decreased, in the last 20 years: Obesity rates in U.S. men aged 20–40 increased only 4% between 1999 and 2008 [ 19 ]; rates of illicit drug use among US citizens aged 12 or older have been relatively stable over the last 15 years [ 20 ]; and smoking rates for US adults declined from 25% in 1993 to 19% in 2011 [ 21 ]. Other authors propose psychological factors. Yet, how likely is it that anxiety and depression account for the sharp rise in youthful sexual difficulties given the complex relationship between sexual desire and depression and anxiety? Some depressed and anxious patients report less desire for sex while others report increased sexual desire [ 22 25 ]. Not only is the relationship between depression and ED likely bidirectional and co-occurring, it may also be the consequence of sexual dysfunction, particularly in young men [ 26 ]. While it is difficult to quantify rates of other psychological factors hypothesized to account for the sharp rise in youthful sexual difficulties, such as stress, distressed relationships, and insufficient sex education, how reasonable is it to presume that these factors are (1) not bidirectional and (2) have mushroomed at rates sufficient to explain a rapid multi-fold increase in youthful sexual difficulties, such as low sexual desire, difficulty orgasming, and ED?

Traditionally, ED has been seen as an age-dependent problem [ 2 ], and studies investigating ED risk factors in men under 40 have often failed to identify the factors commonly associated with ED in older men, such as smoking, alcoholism, obesity, sedentary life, diabetes, hypertension, cardiovascular disease, and hyperlipidemia [ 16 ]. ED is usually classified as either psychogenic or organic. Psychogenic ED has been related to psychological factors (e.g., depression, stress, generalized anxiety, or performance anxiety) while organic ED has been attributed to physical conditions (e.g., neurological, hormonal, anatomical, or pharmacologic side effects) [ 17 ]. For men under 40 the most common diagnosis is psychogenic ED, and researchers estimate that only 15%–20% of cases are organic in origin [ 18 ].

In the last few years, research using a variety of assessment instruments has revealed further evidence of an unprecedented increase in sexual difficulties among young men. In 2012, Swiss researchers found ED rates of 30% in a cross-section of Swiss men aged 18–24 using the International Index of Erectile Function (IIEF-5) [ 8 ]. A 2013 Italian study reported one in four patients seeking help for new onset ED were younger than 40, with rates of severe ED nearly 10% higher than in men over 40 [ 9 ]. A 2014 study on Canadian adolescents reported that 53.5% of males aged 16–21 had symptoms indicative of a sexual problem [ 10 ]. Erectile dysfunction was the most common (26%), followed by low sexual desire (24%), and problems with orgasm (11%). The results took the authors by surprise, “It is unclear why we found such high rates overall, but especially the high rates among both male and female participants rather than female participants alone, as is common in the adult literature” [ 10 ] (p.638). A 2016 study by this same group assessed sexual problems in adolescents (16–21 years) in five waves over a two-year period. For males, persistent problems (in at least one wave) were low sexual satisfaction (47.9%), low desire (46.2%), and problems in erectile function (45.3%). The researchers noted that over time rates of sexual problems declined for females, but not for males [ 11 ]. A 2014 study of new diagnoses of ED in active duty servicemen reported that rates had more than doubled between 2004 and 2013 [ 12 ]. Rates of psychogenic ED increased more than organic ED, while rates of unclassified ED remained relatively stable [ 12 ]. A 2014 cross-sectional study of active duty, relatively healthy, male military personnel aged 21–40 employing the five-item IIEF-5 found an overall ED rate of 33.2% [ 13 ], with rates as high as 15.7% in individuals without posttraumatic stress disorder [ 14 ]. The researchers also noted that sexual dysfunctions are subject to underreporting biases related to stigmatization [ 14 ], and that only 1.64% of those with ED had sought prescriptions for phosphodiesterase-5 inhibitors through the military [ 13 ]. A second analysis of the military cross-sectional data revealed that the increased sexual functioning problems were associated with “sexual anxiety” and “male genital self-image” [ 14 ]. A 2015 “Brief Communication” reported ED rates as high as 31% in sexually active men and low sexual desire rates as high as 37% [ 6 ]. Finally, another 2015 study on men (mean age approximately 36), reported that ED accompanied by a low desire for partnered sex is now a common observation in clinical practice among men seeking help for their excessive sexual behavior, who frequently “use pornography and masturbate” [ 15 ].

In contrast, recent studies on ED and low sexual desire document a sharp increase in prevalence of such dysfunctions in men under 40. One clear demonstration of this phenomenon relates to ED, and compares very large samples, all of which were assessed using the same (yes/no) question about ED as part of the Global Study of Sexual Attitudes and Behavior (GSSAB). In 2001–2002, it was administered to 13,618 sexually active men in 29 countries [ 5 ]. A decade later, in 2011, the same (yes/no) question from the GSSAB was administered to 2737 sexually active men in Croatia, Norway and Portugal [ 6 ]. The first group, in 2001–2002, were aged 40–80. The second group, in 2011, were 40 and under. Based on the findings of historical studies cited earlier, older men would be expected to have far higher ED rates than the negligible rates of younger men [ 2 7 ]. However, in just a decade, things changed radically. The 2001–2002 rates for older men 40–80 were about 13% in Europe [ 5 ]. By 2011, ED rates in young Europeans, 18–40, ranged from 14%–28% [ 6 ].

Up until the last decade, rates of ED were low in sexually active men under 40, and did not begin to rise steeply until thereafter [ 1 2 ]. A 1999 major cross-sectional study reported erectile dysfunction in 5%, and low sexual desire in 5% of sexually active men, ages 18 to 59 [ 3 ], and a 2002 meta-analysis of erectile-dysfunction studies reported consistent rates of 2% in men under 40 (except for the preceding study) [ 2 ]. These data were gathered before Internet “porn tube sites” enabled wide access to sexually explicit videos with no download required. The first of these “tube sites” appeared in September 2006 [ 4 ].

1.2. Is Internet Pornography Use a Factor In Today's Sexual Dysfunctions?

Kinsey Institute researchers were among the first to report pornography-induced erectile-dysfunction (PIED) and pornography-induced abnormally low libido, in 2007 [ 27 ]. Half of subjects recruited from bars and bathhouses, where video pornography was “omnipresent”, were unable to achieve erections in the lab in response to video porn. In talking to the subjects, researchers discovered that high exposure to pornography videos apparently resulted in lower responsivity and an increased need for more extreme, specialized or “kinky” material to become aroused. The researchers actually redesigned their study to include more varied clips and permit some self-selection. A quarter of the participants’ genitals still did not respond normally [ 27 ].

The New Naked , urology professor Harry Fisch reported that excessive Internet pornography use impairs sexual performance in his patients [ The Brain That Changes Itself that removal of Internet pornography use reversed impotence and sexual arousal problems in his patients [ Since then, evidence has mounted that Internet pornography may be a factor in the rapid surge in rates of sexual dysfunction. Nearly six out of 10 of 3962 visitors seeking help on the prominent “MedHelp.org ED Forum”, who mentioned their ages, were younger than 25. In that analysis of eight years of posts and comments, among words commonly linked with the mental aspect of ED (non-organic ED), “porn” appeared most frequently by far [ 28 ]. A 2015 study on high school seniors found that Internet pornography use frequency correlated with low sexual desire [ 29 ]. Of those who consumed Internet pornography more than once a week, 16% reported low sexual desire, compared with 0% in non-consumers (and 6% for those who consumed less than once a week). Another 2015 study of men (average age 41.5) seeking treatment for hypersexuality, who masturbated (“typically with very frequent pornography use”) seven or more hours per week, found that 71% had sexual dysfunctions, with 33% reporting difficulty orgasming [ 30 ]. Anxiety about sexual performance may impel further reliance on pornography as a sexual outlet. In a 2014 functional magnetic resonance imaging (fMRI) study, 11 of the 19 compulsive Internet pornography users (average age 25), whose brains were scanned for evidence of addiction, reported that as a result of excessive use of Internet pornography they had “experienced diminished libido or erectile function specifically in physical relationships with women (although not in relationship to the sexually explicit material)” [ 31 ]. Clinicians have also described pornography-related sexual dysfunctions, including PIED. For example, in his book, urology professor Harry Fisch reported that excessive Internet pornography use impairs sexual performance in his patients [ 32 ], and psychiatry professor Norman Doidge reported in his bookthat removal of Internet pornography use reversed impotence and sexual arousal problems in his patients [ 33 ]. In 2014, Bronner and Ben-Zion reported that a compulsive Internet pornography user whose tastes had escalated to extreme hardcore pornography sought help for low sexual desire during partnered sex. Eight months after stopping all exposure to pornography the patient reported experiencing successful orgasm and ejaculation, and succeeded in enjoying good sexual relations [ 34 ]. To date, no other researchers have asked men with sexual difficulties to remove the variable of Internet pornography use in order to investigate whether it is contributing to their sexual difficulties.

31,35,36,37,38,39,40,41,42,30,31,35,43,41,39,40,43,44,45,46, While such intervention studies would be the most illuminating, our review of the literature finds a number of studies that have correlated pornography use with arousal, attraction, and sexual performance problems [ 27 43 ], including difficulty orgasming, diminished libido or erectile function [ 27 44 ], negative effects on partnered sex [ 37 ], decreased enjoyment of sexual intimacy [ 37 45 ], less sexual and relationship satisfaction [ 38 47 ],a preference for using Internet pornography to achieve and maintain arousal over having sex with a partner [ 42 ], and greater brain activation in response to pornography in those reporting less desire for sex with partners [ 48 ]. Again, Internet pornography use frequency correlated with low sexual desire in high school seniors [ 29 ]. Two 2016 studies deserve detailed consideration here. The first study claimed to be the first nationally-representative study on married couples to assess the effects of pornography use with longitudinal data. It reported that frequent pornography consumption at Wave 1 (2006) was strongly and negatively related with participants’ marital quality and satisfaction with their sex life at Wave 2 (2012). The marriages most negatively affected were those of men who were viewing pornography at the highest frequencies (once a day or more). Assessing multiple variables, the frequency of pornography use in 2006 was the second strongest predictor of poor marital quality in 2012 [ 47 ]. The second study claimed to be the only study to directly investigate the relationships between sexual dysfunctions in men and problematic involvement in OSAs (online sexual activities). This survey of 434 men reported that lower overall sexual satisfaction and lower erectile function were associated with problematic Internet pornography use [ 44 ]. In addition, 20.3% of the men said that one motive for their pornography use was “to maintain arousal with my partner” [ 44 ]. In a finding that may indicate escalation of pornography use, 49% described sometimes “searching for sexual content or being involved in OSAs that were not previously interesting to them or that they considered disgusting” [ 44 ] (p.260). Finally, a significant percentage of the participants (27.6%) self-assessed their consumption of OSAs as problematic. While this rate of problematic pornography use may appear to be high, another 2016 study on 1298 men who had viewed pornography in the last six months reported that 28% of participants scored at or above the cutoff for hypersexuality disorder [ 49 ].

53,54,55,53,30, Our review also included two 2015 papers claiming that Internet pornography use is unrelated to rising sexual difficulties in young men. However, such claims appear to be premature on closer examination of these papers and related formal criticism. The first paper contains useful insights about the potential role of sexual conditioning in youthful ED [ 50 ]. However, this publication has come under criticism for various discrepancies, omissions and methodological flaws. For example, it provides no statistical results for the erectile function outcome measure in relation to Internet pornography use. Further, as a research physician pointed out in a formal critique of the paper, the papers’ authors, “have not provided the reader with sufficient information about the population studied or the statistical analyses to justify their conclusion” [ 51 ]. Additionally, the researchers investigated only hours of Internet pornography use in the last month. Yet studies on Internet pornography addiction have found that the variable of hours of Internet pornography use alone is widely unrelated to “problems in daily life”, scores on the SAST-R (Sexual Addiction Screening Test), and scores on the IATsex (an instrument that assesses addiction to online sexual activity) [ 52 56 ]. A better predictor is subjective sexual arousal ratings while watching Internet pornography (cue reactivity), an established correlate of addictive behavior in all addictions [ 52 54 ]. There is also increasing evidence that the amount of time spent on Internet video-gaming does not predict addictive behavior. “Addiction can only be assessed properly if motives, consequences and contextual characteristics of the behavior are also part of the assessment” [ 57 ]. Three other research teams, using various criteria for “hypersexuality” (other than hours of use), have strongly correlated it with sexual difficulties [ 15 31 ]. Taken together, this research suggests that rather than simply “hours of use”, multiple variables are highly relevant in assessment of pornography addiction/hypersexuality, and likely also highly relevant in assessing pornography-related sexual dysfunctions.

A second paper reported little correlation between frequency of Internet pornography use in the last year and ED rates in sexually active men from Norway, Portugal and Croatia [ 6 ]. These authors, unlike those of the previous paper, acknowledge the high prevalence of ED in men 40 and under, and indeed found ED and low sexual desire rates as high as 31% and 37%, respectively. In contrast, pre-streaming Internet pornography research done in 2004 by one of the paper’s authors reported ED rates of only 5.8% in men 35–39 [ 58 ]. Yet, based on a statistical comparison, the authors conclude that Internet pornography use does not seem to be a significant risk factor for youthful ED. That seems overly definitive, given that the Portuguese men they surveyed reported the lowest rates of sexual dysfunction compared with Norwegians and Croatians, and only 40% of Portuguese reported using Internet pornography “from several times a week to daily”, as compared with the Norwegians, 57%, and Croatians, 59%. This paper has been formally criticized for failing to employ comprehensive models able to encompass both direct and indirect relationships between variables known or hypothesized to be at work [ 59 ]. Incidentally, in a related paper on problematic low sexual desire involving many of the same survey participants from Portugal, Croatia and Norway, the men were asked which of numerous factors they believed contributed to their problematic lack of sexual interest. Among other factors, approximately 11%–22% chose “I use too much pornography” and 16%–26% chose “I masturbate too often” [ 60 ].

Again, intervention studies would be the most instructive. However, with respect to correlation studies, it is likely that a complex set of variables needs to be investigated in order to elucidate the risk factors at work in unprecedented youthful sexual difficulties. First, it may be that low sexual desire, difficulty orgasming with a partner and erectile problems are part of the same spectrum of Internet pornography-related effects, and that all of these difficulties should be combined when investigating potentially illuminating correlations with Internet pornography use.

Second, although it is unclear exactly which combination of factors may best account for such difficulties, promising variables to investigate in combination with frequency of Internet pornography use might include (1) years of pornography-assisted versus pornography-free masturbation; (2) ratio of ejaculations with a partner to ejaculations with Internet pornography; (3) the presence of Internet pornography addiction/hypersexuality; (4) the number of years of streaming Internet pornography use; (5) at what age regular use of Internet pornography began and whether it began prior to puberty; (6) trend of increasing Internet pornography use; (7) escalation to more extreme genres of Internet pornography, and so forth.