Menopause Report Used Male Data: Why Clinical Trials Exclude Women 2026

A recent report on menopause from the Spanish Agency for Food Safety and Nutrition (AESAN) has sparked outrage after it was revealed that its nutritional recommendations were based on studies conducted exclusively in men. The error is glaring: a condition that affects only women was addressed using data from the opposite sex.

While the agency has since faced calls to correct the report, the incident is not an isolated lapse. It is a window into a much larger problem that has plagued medical research for decades—the systematic exclusion of women from clinical trials.

Why the Menopause Report Ignored Women

The AESAN report aimed to provide dietary guidance for women going through menopause, a stage marked by significant hormonal shifts. Yet the studies it cited enrolled only male participants. This is not a trivial oversight; it reflects a deeper bias in how research questions are framed and which populations are deemed worthy of study.

Menopause is defined by the cessation of ovarian function, something men do not experience. Using male data to inform menopause care is not just inappropriate—it can be harmful. The report's authors have since been asked to revise their conclusions, but the damage to public trust is done.

The incident raises a fundamental question: how many other health recommendations for women are built on a foundation of male-only evidence? The answer, according to historians of science, is uncomfortably many.

The Historical Roots of Male-Only Research

For much of the 20th century, clinical trials routinely excluded women of childbearing age. The rationale was often paternalistic: protecting women (and potential fetuses) from experimental risks. But the consequence was that women were left out of the very research that would determine the safety and efficacy of treatments they would later receive.

This exclusion was not limited to reproductive health. Cardiovascular disease, lung cancer, and diabetes—conditions that affect both sexes—were studied predominantly in men. As a result, symptoms that present differently in women, such as heart attack signs, were often missed, and drug dosages were calibrated to male physiology.

It wasn't until the 1990s that major funding agencies began mandating the inclusion of women in clinical trials. Yet even today, compliance is uneven, and analysis often fails to disaggregate results by sex. The AESAN report is a stark reminder that the legacy of male-only research persists.

Biological Differences That Make Sex-Specific Data Essential

Men and women differ in far more than reproductive organs. Hormonal profiles, fat distribution, immune system function, and even organ size vary significantly between the sexes. These differences influence how diseases manifest and how drugs are metabolized.

For example, women often experience more severe side effects from medications because dosages were optimized for men. A drug tested only in men may be less effective or more toxic in women. Similarly, research focused solely on male patients can overlook sex-specific risk factors and symptoms.

Including both men and women in clinical trials is not about political correctness—it is about scientific rigor. Without representative samples, study results cannot be reliably generalized to the population that will ultimately use the interventions.

Consequences of the Gender Data Gap

The gender data gap has real-world consequences. Women are more likely to experience adverse drug reactions, yet the underlying causes are often poorly understood because the data simply isn't there. Diagnostic delays are common for conditions like heart disease and autoimmune disorders, partly because symptoms in women are less recognized.

Beyond individual harm, the gap perpetuates systemic inequities. When research ignores women, clinical guidelines follow suit, and healthcare providers are left without evidence-based tools to treat half their patients. The menopause report is a case in point: it offered nutritional advice that may not have been validated for the very population it targeted.

Correcting this requires more than revising a single report. It demands sustained pressure on institutions to enforce inclusive research practices and to analyze data by sex. It also requires educating researchers about the importance of sex as a biological variable.

What Needs to Change in Clinical Research

The AESAN incident has prompted renewed calls for accountability. The agency has been asked to review its methodology and ensure that future recommendations are based on data that include women. But systemic change requires broader action.

• Mandatory inclusion: Funders and regulators must enforce policies that require the inclusion of women in all clinical trials unless there is a compelling scientific reason not to.
• Sex-disaggregated analysis: Researchers should routinely analyze and report outcomes by sex, not just aggregate data.
• Transparency: Journals and agencies should require authors to justify any sex-based exclusions and to disclose the limitations of male-only data.
• Education: Training programs for researchers and clinicians should emphasize sex differences and the consequences of ignoring them.
• Public scrutiny: As the menopause report shows, public awareness can drive institutional corrections and hold agencies accountable.

These steps are not radical; they are basic requirements for producing reliable, generalizable evidence. The fact that they are still needed in the 21st century speaks to how deeply embedded the bias remains. Context on how this played out before sits in Menopause Report Used Male Data: Why Clinical Trials Exclude Women. A companion piece, The Dancing Plague of 1518: What Really Happened in Strasbourg, approaches the same subject from another angle.

Lessons from the Menopause Report Controversy

The AESAN report is a cautionary tale. It shows that even well-intentioned institutions can fall into the trap of using male data for women's health issues. It also demonstrates that the public is watching—and willing to demand better. The background to this story is set out in England's Inroads Against Spain: Data Shows Need for Clinical Edge. A related thread runs through Health: latest articles.

For healthcare professionals, the incident underscores the need to critically appraise the evidence behind clinical guidelines. For researchers, it is a reminder that inclusivity is not optional. For women, it is a validation of long-standing frustrations about being overlooked by the medical establishment. Earlier coverage in Where to Scatter Ashes and How to Donate Your Body to Science shows how the argument developed. A closer look at the same subject appears in Plague in Russia and the Stalled WHO Pandemic Agreement.

The path forward requires vigilance. Every study, every report, and every guideline should be examined for who was included—and who was left out. Only then can we ensure that medical advice is truly evidence-based for everyone. Anyone following the wider picture can start with Nicolas Cage War Film Fortitude Sparks $105 Million Lawsuit. The same theme surfaces in ChatGPT, Gemini, Grok and Claude All Down: Claude Still Not Recovered, which takes a different angle.