Military aged Britons: too sick to serve?

A recent YouGov poll surveyed the attitudes of Britons aged eligible to serve in the army, navy or air force in the event of a conflict. It suggested that 38% of those of military age, between 18 and 41, would refuse to be conscripted in the event of a new world war.[1]

With conflict in Ukraine and the Middle East, commentators believe Britain could be involved in a conflict. The UK defence secretary, Grant Shapps, said in January that the country was moving from a “post war to a pre-war world”.[2]

Britain’s most senior army officer, General Sir Patrick Sanders, argued that Britain must prepare for conflict by training a citizen army.[3]

Leaving aside whether Britons would be willing to fight in a war, there is real concern about whether many military aged people would be able to fight. In the YouGov survey mentioned above, one in six people of military age believed they would be rejected from military service on health grounds.

This article explores the physical and mental health of military age Britons and considers the implications of their health on the effectiveness of any potential British military effort.

One major problem is dental health. In 2021, over half of British people showed signs of gum disease, a third of the population suffered from untreated tooth decay and an estimated ten million people were waiting for routine dental treatment in the UK. The prevalence of poor dental health was nearly four times higher in deprived areas compared to the general population. It is believed that dental health is getting worse.[4]

Physical health is also important; an indicator of a population’s fitness is its obesity rate. However, the rates for Britain suggested many Britons are unfit. For people aged 25-44 in England, around 60% are overweight or obese.[5] The number in this category has doubled in the last 30 years and the trend is upwards.[6] As a result of the health conditions that some people develop, such as type 2 diabetes, one in 20 young people are ‘economically inactive’ due to health reasons.[7]

The most worrying health issue is the poor mental health among military age Britons. Young people aged 18 to 24 have the worst mental health of any age group.[8] In 2021/22, 34% of young people in this group reported symptoms of a mental disorder, such as depression, anxiety or bipolar disorder, up 40% on the figure in 2000.[9] In 2010/11, around 1% of university students reported a mental health issue to their university; in 2020/21 it was 5.5%.[10] Surveys suggest that between a half and two thirds of students had had some mental health problem and the suicide rate among students was 2.7 times higher than for the general population.[11][12] The poor mental health among many students is down to many factors but includes  moving away from home, living independently and the absence of familiar emotional networks.[13]

The poor mental and physical health among younger Britons would have significant impacts on the feasibility and efficiency of raising and maintaining a mass citizen military force in the UK.

Firstly, with high rates of obesity, untreated dental issues and mental health conditions, a substantial portion of the military-age population might be deemed unfit for service based on health screenings. This could lead to challenges in meeting recruitment targets necessary for a large-scale conscription and put an increased burden on those who are passed as medically fit.

Secondly, even those who pass initial health screenings might face difficulties during intense physical training. Issues like poor dental health and obesity could lead to increased medical problems, reducing the overall effectiveness of training and preparedness programmes.

Additionally, soldiers with underlying health issues are at higher risk of injuries and illnesses, which can decrease their effectiveness in the field. Mental health problems can also affect decision-making, stress management and team cohesion, further impacting operational capabilities. There could be a significant issue with suicide in among conscripted recruits.

Maintaining a large force with such health issues would likely result in higher medical and logistical costs. The need for additional medical support and potentially lower overall troop durability could strain military resources and sustainability.

Finally, the high prevalence of mental health issues could impact morale and mental resilience, critical in combat situations. Lower morale could lead to higher dropout rates and less effective units.

The poor health of military recruits in Britain is not a new issue. Between 2019/20 and 2023/24, the army rejected 125,871 applicants to join the army, 60% of them on ‘medical grounds’.[14] Over a hundred years ago, Britain faced a similar problem. During the 1899-1902 South African War against the Boer Republics in southern Africa, 60% of civilian volunteers were rejected as medically unfit.[15]

After that conflict, the British government investigated the causes of the high rejection rate fearing ‘biological degeneracy’. However, the official Committee on Physical Deterioration was set up in 1903 to explore the issue identified poverty, malnourishment and living conditions as being responsible for the high rejection rate. It recommended government action and subsequent administrations introduced a range of measures including compulsory medical inspections of children in schools, free school meals for the very poor and training in mothering skills for working class women.

Is it time for similar action today to tackle the mental and physical health of British young adults considering the increasingly unstable world? Action will take time and these health issues cannot be fixed overnight. The levels of morbidity are real and pose a major public health challenge to the individuals concerned and society. Tackling these health challenges would have potentially major benefits for Britain’s peacetime economic health and productivity. It may also create the basis for a future mass citizen military force in should the need arise.


[1] https://yougov.co.uk/politics/articles/48473-more-than-a-third-of-under-40s-would-refuse-conscription-in-the-event-of-a-world-war Accessed 24 March 2024.

[2] UK citizen army: Preparing the ‘pre-war generation’ for conflict – BBC News Accessed 13 April 2024.

[3] Britain must train citizen army, military chief warns – BBC News Accessed 13 April 2024.

[4] The Great British Oral Health Report ({my}dentist, 2021).

[5] Carl Baker, Obesity statistics, House of Commons Library Research Briefing (London: House of Commons Library, 12 January 2023), p.7.

[6] Carl Baker, Obesity statistics, House of Commons Library Research Briefing (London: House of Commons Library, 12 January 2023), p.6.

[7] https://www.bbc.co.uk/news/health-68399392 accessed 15 April 2024.

[8] https://www.bbc.co.uk/news/health-68399392 accessed 15 April 2024.

[9] https://www.bbc.co.uk/news/health-68399392 accessed 15 April 2024.

[10] Joe Lewis and Paul Bolton, Student mental health in England: Statistics, policy, and guidance (London: House of Commons Library, 30 May 2023), p.4.

[11] Joe Lewis and Paul Bolton, Student mental health in England: Statistics, policy, and guidance (London: House of Commons Library, 30 May 2023), pp.9-10.

[12] Joe Lewis and Paul Bolton, Student mental health in England: Statistics, policy, and guidance (London: House of Commons Library, 30 May 2023), p.11.

[13] Joe Lewis and Paul Bolton, Student mental health in England: Statistics, policy, and guidance (London: House of Commons Library, 30 May 2023), pp.12-13.

[14] Over 125,000 applicants rejected from British Army (ukdefencejournal.org.uk) Accessed 15 April 2024.

[15] R. Roberts, The Classic Slum: Salford Life in the First Quarter of the Century, (London: 1990), p.79.