Transgender Demographics

“How many trans people are there?” and “Why has the number increased?” are two of the most frequent questions in the public debate on gender identity. The answers, often simplified or exploited, deserve a careful analysis of the available data. This article gathers the main demographic estimates, explains why the numbers have changed over time, and clarifies what statistics on the transgender population mean—and what they do not mean.

The Measurement Problem

Before examining the numbers, it is essential to understand how they are collected. The prevalence of transgender people in the population depends critically on three factors: the definition used, the collection method, and the social context in which the question is asked.

Different Definitions, Different Numbers

The systematic review by Zhang et al. (2020), published in the International Journal of Transgender Health, highlights that prevalence estimates vary enormously depending on what is meant by “transgender” [7]. If only those who have received a clinical diagnosis or undergone medical transition are counted, the figures are very low: in their meta-analysis in European Psychiatry, Arcelus et al. (2015) reported an overall prevalence of 4.6 per 100,000 people, or about 0.005% [4]. If, however, anonymous surveys based on self-identification are used, the percentages rise significantly. As noted by Goodman et al. (2019), clinical studies report estimates between 0.001% and 0.03%, while those based on self-identification reach values between 0.1% and 2.0% [6].

This difference does not indicate that the higher estimates are “inflated.” Rather, it indicates that the vast majority of transgender people never access specialized clinical services—by choice, financial inability, bureaucratic barriers, or fear of stigmatization.

The Role of Social Context

A person living in a context where transgender identity is heavily stigmatized is less likely to respond affirmatively to a survey, even an anonymous one. This phenomenon, known as social desirability bias, means that estimates collected in less inclusive societies tend to be systematically lower, not because there are fewer trans people, but because fewer people feel safe expressing themselves [7].

Global Estimates: What We Know

The Williams Institute Estimates

The UCLA Williams Institute is the most widely cited research center on this subject. In 2016, Flores et al. estimated that 0.6% of U.S. adults—about 1.4 million people—identified as transgender, using data from the Behavioral Risk Factor Surveillance System (BRFSS) [2]. In 2022, Herman, Flores, and O’Neill updated these estimates: over 1.6 million adults and youth in the United States identified as transgender, with youth aged 13 to 17 making up 18% of the total transgender population, up from 10% in previous estimates [1].

The latest Williams Institute estimates, based on updated data, indicate that approximately 2.8 million people ages 13 and older—1.0% of the U.S. population in that age group—identify as transgender [1]. Among adults, the percentage is 0.8% (over 2.1 million), while among youth aged 13 to 17 it reaches 3.3% (about 724,000 youth) [1]. The increase from previous estimates partly reflects improvements in data collection methods, especially regarding youth.

Meerwijk and Sevelius’s Meta-Regression

A particularly relevant study is the meta-regression by Meerwijk and Sevelius (2017), published in the American Journal of Public Health [3]. The researchers analyzed 12 surveys based on probability samples conducted between 2007 and 2015 in the United States. Their model explained 62.5% of the heterogeneity among the studies and identified a significant time effect: prevalence estimates increased with each successive year [3]. Extrapolating to 2016, the model suggested a U.S. transgender population size of approximately 390 adults per 100,000, or about 1 million people.

The crucial finding of this study is not the figure itself, but the statistical demonstration that the increase over time is a robust and predictable trend—consistent with a phenomenon of progressive visibility, not a sudden change in the population [3].

International Estimates

Globally, the Ipsos LGBT+ Pride 2023 survey, conducted among more than 22,500 adults in 30 countries, found that 1% of the global population describes themselves as transgender, and a further 1% as non-binary or gender-fluid [8]. Generational differences are significant: 6% of Generation Z and 3% of Millennials identify as transgender, non-binary, or gender-fluid, compared to 1% of Generation X and Baby Boomers [8].

Applying the most conservative estimates from scientific literature (0.3-0.6%) to the global population yields a figure between 25 and 50 million transgender people worldwide. If more recent estimates are used, which include self-identification and non-binary identities, the number could be significantly higher.

The Situation in Italy

The Absence of Official Data

Italy does not have an official census of the transgender population. ISTAT (the Italian National Institute of Statistics) has never conducted a specific demographic survey on the prevalence of transgender identity in the general population. Available data come mainly from specialized clinical centers, which by definition only capture a fraction of the population.

The SPoT Project

In 2020, the SPoT project (Estimate of the Adult Transgender Population in Italy) was launched, promoted by the Careggi University Hospital (AOU) in Florence in collaboration with the National Institute of Health (ISS) and The Bridge Foundation [11]. This is the first systematic survey on the size of the Italian transgender population. Before SPoT, the available data dated back to the 1992-2008 period and recorded extremely low numbers (424 trans women and 125 trans men), based exclusively on people who had undergone a clinical transition pathway [11].

Estimates for Italy

Applying percentages from international literature to the Italian population of approximately 59 million inhabitants, rough estimates can be formulated:

• With the conservative estimate of 0.3%: about 177,000 people
• With the 0.6% estimate: about 354,000 people
• With the broader 1% estimate (which includes non-binary identities): about 590,000 people

These figures are consistent with unofficial estimates reported in Italian literature, which indicate a transgender population between 150,000 and 500,000 people. The 2023 Ipsos survey found that in Italy, 4% of the population defines themselves as transgender, gender-fluid, or non-binary [8], but this figure uses a very broad definition that includes the entire spectrum of non-cisgender gender identities.

The ISTAT-UNAR Survey on Discrimination

Although ISTAT has not produced prevalence estimates, the 2023 ISTAT-UNAR survey on workplace discrimination provided important data on the experiences of trans and non-binary people in Italy [12]. Out of 630 respondents, 34.1% were trans men, 19.4% were trans women, and 46.5% were non-binary people. The data reveal very high levels of discrimination: 66.1% experienced discrimination at school, one in two while looking for work, and 40.6% in the workplace [12]. These data, while not prevalence estimates, help us understand why many trans people prefer to remain invisible—which in turn influences all estimates based on self-identification.

Why the Numbers Seem to Be Increasing

The “Visibility Threshold” Phenomenon

The apparent increase in transgender people is not a unique phenomenon in the history of social demographics. Whenever a previously stigmatized characteristic becomes more accepted, the number of people who openly declare it increases. Not because there are more people with that characteristic, but because the visibility threshold is lowered.

The Analogy with Left-Handedness

The most cited parallel in the literature is that of left-handedness. At the beginning of the 20th century, in many Western countries, left-handed people were systematically forced to use their right hand. The recorded prevalence of left-handedness fluctuated between 3% and 4%. When schools stopped imposing the right hand—a gradual process that occurred between the 1920s and 1960s—the percentage of left-handed people increased rapidly, stabilizing around 12%, where it remains today.

No one ever argued that schools “created” more left-handed people by stopping their punishment. Simply put, the number of left-handed people had always been around 12%; repression kept it artificially low. The same principle applies to the visibility of transgender people: the gradual removal of stigma allows a growing number of people to express an identity that was always present.

The Same Pattern for Homosexuality

An identical trend is observed for sexual orientation. The percentage of people who identify as gay, lesbian, or bisexual has steadily increased over recent decades—not because there are “more homosexuals”, but because more people feel free to answer honestly. Gallup polls in the United States show that the percentage of adults identifying as LGBT+ rose from 3.5% in 2012 to 7.6% in 2023, with almost the entire increase concentrated in younger generations.

The Generational Effect

The review by Nolan, Kuhner, and Dy (2019) documented two clear trends: growth over time in the proportion of people identifying as transgender, and higher prevalence among younger generations [5]. Among U.S. adults, transgender identification was more common in the 18-24 age group (0.7%) compared to older age groups [5].

This data is sometimes interpreted as evidence that young people “become trans as a trend”. But the simplest explanation, and the one most consistent with the data, is that young people are growing up in an environment with greater access to information and less stigma, which facilitates the recognition and expression of gender identity [5]. It’s not that there are more trans youth; it’s that more trans youth can say so.

Prevalence and Incidence: A Fundamental Distinction

In public debate, prevalence (how many people have a given characteristic at a given time) is often confused with incidence (how many new cases occur over a period). The increase in the recorded prevalence of trans people does not imply an increase in incidence—meaning it doesn’t mean “more trans people are being born.”

Arcelus et al. (2015) documented an increase in reported prevalence over the last five decades, but the authors themselves emphasize that the estimates were based almost exclusively on clinical data and did not capture the general population [4]. As collection methods have become refined—moving from clinical registries to population surveys, and from indirect questions to explicit questions about gender identity—the estimates have naturally increased.

To use an analogy: if we count the fish in a lake only by looking from the shore, we will get a low number. If we use a sonar, the number will be higher. Not because there are more fish, but because our measuring tool has improved.

What Detransition Rates Tell Us

Detransition data offers an additional perspective on the accuracy of estimates and the reliability of self-identification.

Surgical Regret Rates

The meta-analysis by Bustos et al. (2021), published in Plastic and Reconstructive Surgery - Global Open, examined 27 studies and 7,928 transgender patients who had undergone gender-affirming surgery. The overall regret rate was 1%, one of the lowest in the surgical field [10]. This data suggests that the vast majority of people who embark on a medical transition path do so with a consolidated awareness of their identity.

The Causes of Detransition

The study by Turban et al. (2021), based on data from the U.S. Transgender Survey (27,715 participants), found that 13.1% of people who had undertaken a gender-affirming pathway had experienced a period of detransition. However, 82.5% of these individuals attributed their detransition to external factors: family pressure (35.5%), social stigma (32.5%), or employment difficulties (26.8%). Only 2.4% indicated doubts about their gender identity as the reason for detransition [9].

This fact is crucial: detransition does not indicate that “the person wasn’t really trans,” but rather that social conditions made it unsustainable to live openly as a transgender person [9]. In many cases, people who detransition resume their journey when circumstances allow.

What This Means for Prevalence Estimates

If the “error” rate in self-identification were high—meaning if many people identified as trans “by mistake”—we would expect much higher rates of regret and detransition. The fact that surgical regret rates are around 1% [10] and that the majority of detransitions are motivated by external pressures [9] suggests that self-identification as a transgender person is, in the vast majority of cases, stable and accurate.

The Implications of the Data

It’s Not a Matter of Small Numbers

Even using the most conservative estimates, we are talking about millions of people globally and hundreds of thousands in Italy. These individuals need access to appropriate healthcare, legal protection from discrimination, representation in public policies, and visibility in social discourse.

The Growth Will Stabilize

If the left-handedness model is predictive—and the literature suggests it is—the percentage of people openly identifying as transgender will continue to grow until it reaches a natural plateau, determined by the true prevalence in the population. We do not yet know what this plateau is, but current data suggests we are still in the ascending phase of the curve [3]. Each generation grows up with less stigma and more information, and this is reflected in progressively higher estimates—not because people change, but because the context in which they can express themselves changes.

The Importance of Data Collection

The absence of official data in many countries, including Italy, is not just an academic problem. Without reliable estimates on the size of the transgender population, it is impossible to adequately plan healthcare services, evaluate the effectiveness of inclusion policies, and measure the impact of discrimination. The SPoT project represents an important step [11], but there is still a long way to go.

Conclusions

Transgender people are not a recent phenomenon and have not “increased” in the commonly understood sense. What has changed are the social conditions that allow a growing number of people to live openly, and the scientific tools that allow us to count them more accurately [3][7].

Available data converge on a few key conclusions: transgender people represent a significant share of the population (between 0.3% and 1% depending on the definitions) [1][4][6]; numbers are higher among younger generations due to greater acceptance [5][8]; self-identification as a trans person is in the vast majority of cases stable and accurate [9][10]; and the apparent increase over time reflects a change in visibility, not in true prevalence [3].

Understanding these data is the first step in addressing the debate with the seriousness it deserves—far from unfounded alarmism and narratives that reduce millions of people to a statistic to be disputed.