Fact Check: An American teenager today has less testosterone than a 68 year old man. Sperm counts are down 50 pe...

Claim Analysis: "An American teenager today has less testosterone than a 68-year-old man. Sperm counts are down 50 percent."

1. Introduction

The claim that "an American teenager today has less testosterone than a 68-year-old man" and that "sperm counts are down 50 percent" was made by Robert F. Kennedy Jr., the U.S. Secretary of Health and Human Services, during a recent interview. This assertion raises significant questions regarding the accuracy of testosterone levels in teenagers compared to older men, as well as the trends in sperm counts over time.

2. What We Know

• Testosterone Levels: Research indicates that testosterone levels in men generally decline with age. A study published in 2022 suggests that the normal testosterone levels for young men (ages 20-44) have been re-evaluated, but it does not provide a direct comparison to older men 3. A fact-check by USA Today states that average testosterone levels for young men have decreased by about 25% from 1999 to 2016, with a 22-year-old male today having testosterone levels similar to those of a 67-year-old male from the year 2000 9.

• Sperm Counts: A meta-analysis published in 2017 found that sperm counts among men in Western countries have declined by approximately 50-60% over the past four decades 9. This statistic is often cited in discussions about male reproductive health, but the exact percentage can vary based on the population studied and the methodologies used.

• Age Comparisons: The claim that teenagers have lower testosterone than older men lacks specific empirical support. While it is established that testosterone levels decline with age, the direct comparison between teenagers and older men, particularly in the context of the claim made by Kennedy, is not well-documented in the available literature.

3. Analysis

The sources supporting the claim primarily stem from statements made by Robert F. Kennedy Jr. in media interviews, which may not be grounded in robust scientific evidence. For instance, the articles from Yahoo and Mediaite report on his statements but do not provide empirical data to substantiate them 678.

Conversely, the USA Today fact-check provides a more nuanced view of testosterone levels, indicating a significant decline over the years but not directly confirming Kennedy's assertion about teenagers specifically 9. The studies referenced in the PMC articles discuss the impact of aging on testosterone and sperm quality but do not directly compare the levels of teenagers to those of older men 12.

Additionally, the context of Kennedy's role as a public figure with a history of controversial statements, particularly regarding health issues, raises questions about potential bias. His claims could be seen as part of a broader narrative concerning public health and environmental factors affecting male reproductive health, which may influence how his statements are received and interpreted.

4. Conclusion

Verdict: Mostly False

The claim that "an American teenager today has less testosterone than a 68-year-old man" is categorized as "Mostly False" due to the lack of direct empirical evidence supporting the specific comparison between teenagers and older men. While it is true that testosterone levels in young men have declined over the years, the assertion lacks robust data to confirm that teenagers specifically have lower testosterone than older men.

Furthermore, while sperm counts have indeed shown a significant decline over the past few decades, the claim's framing may oversimplify a complex issue. The statistics regarding sperm counts vary based on different studies and populations, which adds a layer of uncertainty to the claim.

It is important to acknowledge the limitations in the available evidence, particularly the absence of direct comparisons between the testosterone levels of teenagers and older men. The nuances in the data suggest that while there are trends in testosterone and sperm count, the specific claims made by Kennedy do not hold up under scrutiny.

Readers are encouraged to critically evaluate information and consider the context and sources of claims, especially those made by public figures, to form a well-rounded understanding of the issues at hand.

5. Sources

1. Harris, I. D. (2011). Fertility and the Aging Male. PMC. Link
2. Sharma, R. (2015). Effects of increased paternal age on sperm quality. PMC. Link
3. Zhu, A. (2022). What Is a Normal Testosterone Level for Young Men. University of Michigan. Link
4. Independent. (2025). RFK claims teenage boys in America have less testosterone than 68 year. Link
5. MSN. (2025). RFK Jr. rants about teenage sperm counts and testosterone levels. Link
6. Yahoo News. (2025). RFK Jr claims teenage boys in America have less testosterone. Link
7. Mediaite. (2025). Fox's Jesse Watters Stunned by Wild RFK Jr Rant About Sperm. Link
8. Economic Times. (2025). RKF Jr claims American teens have less testosterone. Link
9. USA Today. (2022). Fact check: Testosterone levels lower by about 25% from 1999-2016. Link
10. Yahoo News. (2025). RFK Jr. Launches Into Bizarre Rant About Teenage Sperm. Link