Elon Musk's contraceptive warning: 'Read the box of anything you…'

Elon Musk has sparked fresh debate with a cautionary post on X, urging people to “read the box of anything you’re taking.” His remark comes in response to new scientific findings on hormonal contraceptives, which suggest potential effects on brain function, emotional regulation, and memory. Musk ’s warning echoes growing concerns that the side effects of widely used medications may be underestimated or underreported. By drawing attention to this issue, the Tesla and SpaceX chief has placed contraceptives and their long-term societal implications at the center of a discussion that bridges health, science, and population dynamics.

The study behind Elon Musk’s contraceptive warning
Musk’s comment was linked to research from Rice University, published in Hormones and Behavior (2025), showing that hormonal contraceptives may alter the ventromedial prefrontal cortex (vmPFC), a brain region tied to emotion regulation and memory. The study found that adolescent girls on contraceptives exhibited stronger emotional responses and recalled fewer details of negative experiences. This aligns with past findings, such as a 2018 Frontiers paper showing that vmPFC damage can reduce empathy, raising questions about potential long-term behavioral consequences.

The Rice study, led by graduate researcher Beatriz Brandao, found that hormonal contraceptives influence not only emotions but also how women regulate and remember them. Women on birth control showed stronger emotional reactions and recalled fewer details of negative events when using strategies like distancing or reinterpretation, a pattern researchers suggest may help protect against reliving distress. At the same time, both contraceptive users and naturally cycling women enhanced memory for positive experiences through immersion, pointing to a role in building resilience. Co-authors Bryan Denny and Stephanie Leal noted that the findings highlight how reproductive hormones shape mental health processes such as stress, depression, and coping, with future studies set to compare different types of contraceptives across menstrual phases.

Read the warnings on the box of anything you’re taking https://t.co/va66xz1gqS

— Elon Musk (@elonmusk) September 1, 2025

Population-level effects and ongoing debate
The post Musk retweeted suggested that contraceptives could influence behavior on a societal scale, even extending to political attitudes. Supporting evidence comes from studies indicating hormonal shifts can affect stress responses, mate preferences, and social decision-making. For instance, a 2013 Psychoneuroendocrinology study showed contraceptive use influenced attraction patterns, while a 2023 Brain, Behavior, and Immunity paper linked synthetic hormones to heightened inflammation and stress.

With over 60 million women in the U.S. using hormonal birth control, the potential for population-wide effects remains an area of scientific and ethical debate. However, many medical experts argue that the benefits of contraceptives, including preventing unintended pregnancies, regulating menstrual cycles, and reducing certain cancer risks, still outweigh the risks for most women. They caution that while side effects warrant further study, alarmist interpretations risk undermining access to one of the most widely used and effective tools in reproductive health.