For decades, a history of asthma could slam the door shut on a military career. Now, the British Army is opening that door, betting that modern medicine and changing tactics will build a stronger, more inclusive force.
Published: July 2025
In a landmark announcement, Britain's Defence Secretary John Healey declared the end of a long-standing ban, clearing the way for individuals with asthma or severe acne to join the armed forces 1 . This radical policy shift aims to tackle a severe recruitment crisis by scrapping "outdated policies" that have historically disqualified a significant portion of the population 1 .
The British Army, at its smallest size in two centuries, is now re-evaluating what it truly means to be "fit to fight" 1 7 . This change prompts a compelling question: Is the army finally catching up with the science of asthma, a condition that affects over 28 million people in the U.S. alone and is deeply influenced by environmental and societal factors 3 ?
The British Army's relationship with health and hygiene dates back to the mid-19th century, driven by the understanding that a healthy force is an effective force 7 . The role of the army medical officer has long been to "advise commanding officers in all matters affecting the health of troops" 7 . This historical focus on population health within the military created a high barrier for chronic conditions like asthma.
The army was discharging approximately 50 soldiers per year for asthma, representing about 1 in 3400 of the army's strength and 6.3% of all medical discharges .
The same study uncovered a critical issue in the recruitment process: medical histories were often missed. Of the discharged soldiers who had a history of childhood asthma, this was identified at the initial recruit examination in only 43% of cases . Furthermore, the natural history of the disease posed a problem; many who experienced a remission of asthma in their early teens saw a relapse around the typical age of enlistment (17-21 years) . This evidence formed the bedrock of the army's cautious, exclusionary policy for decades.
The push for change is driven by necessity. Labour claims the British Army is at its smallest size in 200 years 1 . Latest figures show only 74,296 regular members, a drop of over 5,000 since 2019 1 . Over the past five years, "medical reasons" have become the single biggest cause for rejection, disqualifying 76,187 applicants 1 . In this context, maintaining a blanket ban on a common condition like asthma is a luxury the army can no longer afford.
The NHLBI now funds research into personalized approaches for severe asthma, testing treatments based on a patient's specific biology 5 .
The army now recruits skilled gamers as drone pilots, where traditional physical limitations matter less 1 .
Modern medicine recognizes asthma as a spectrum condition that can be effectively managed in most individuals.
The new policy does not mean that all cases of asthma will be accepted. The army's medical rules have always been "regularly updated and are often considered on a case-by-case basis" 1 . The key change is moving away from an automatic disqualification.
The general principle now is that candidates whose condition "may affect the ability to wear military clothing or to operate military equipment should normally be graded UNFIT, or entry should be deferred until the disease has been successfully treated" 1 . For asthma specifically, the rules state: "Generally speaking, if you require treatment for asthma you will not be eligible. If you have had treatment in the past, then it will depend how long ago that was, how old you were at the time, what your symptoms were, and how much and how long you needed treatment for" 1 . This allows for a nuanced evaluation of each applicant's individual health status.
While physical health standards are evolving, the mental health of military personnel remains a paramount concern. A 2025 review highlights that common mental disorders like depression and anxiety are more prevalent in UK serving personnel and veterans than in the general population 4 . Risk factors include combat exposure, physical injury, and adverse childhood experiences 4 .
This underscores the complexity of building a healthy force. It is not just about relaxing one medical standard, but about fostering an overall environment of "wellbeing" – a term that reflects a more holistic, 21st-century view of soldier health 7 .
The goal is to "draw the very best of British talent" while maintaining the highest standards, creating a force that is both fit to fight and reflective of the nation it serves 1 .
The decision to allow asthma sufferers into the British Army is more than a simple policy tweak; it is a symbol of a larger transformation. It represents a pragmatic adaptation to a recruitment crisis, an embrace of modern medical science, and an alignment with the evolving, technology-driven nature of warfare.
This change acknowledges that the definition of strength and capability is broader than a clean medical slate. By focusing on an individual's overall health and potential, rather than a diagnostic label, the British Army is taking a significant step toward building a more resilient and representative force for the 21st century.
As with any major policy shift, the long-term outcomes will need to be closely watched, but for now, it marks the end of an era of blanket bans and the start of a more nuanced approach to recruiting the nation's defenders.
References will be listed here in the final publication.