Night Shifts and Asthma: A Hidden Health Risk for Women

In today’s 24/7 world, working odd hours has become the norm. From healthcare professionals to factory workers and tech employees, many women find themselves clocking in when the rest of the world is winding down. While night shifts may offer career benefits and flexible schedules, they can also come at a cost, particularly to women's health.

Recent research from the UK reveals a concerning link: women who regularly work night shifts face a significantly higher risk of developing moderate to severe asthma.

Asthma Risk in Women: What the Study Found

A study published in ERJ Open Research ⁽¹⁾ and conducted by researchers at the University of Manchester examined health data from over 274,500 people via the UK Biobank. The goal? To explore how working night shifts might impact asthma risk.

Their findings were striking: women working permanent night shifts were about 50% more likely to develop moderate to severe asthma compared to those working regular daytime hours. Interestingly, this elevated risk was not observed in men, pointing to a gender-specific vulnerability.

What’s Causing the Increased Risk?

The researchers suggest that disruption to the body’s internal clock, also known as the circadian rhythm, could be the main culprit. This internal clock helps regulate everything from sleep to hormone production and immune responses. When it’s thrown off balance, like during night shifts, the body’s normal functioning can be affected.

Testosterone, a hormone that’s been found to offer some protection against asthma, may play a role here. Since women naturally have lower levels of testosterone, they may be more susceptible to asthma when circadian rhythms are disrupted. Hormonal imbalances caused by working at night could increase this vulnerability.

Key Data Insights

The study’s sample included 274,541 participants, out of which:

• 5.3% had asthma.

• 1.9% had moderate to severe asthma (defined by the need for both a preventer inhaler and an additional treatment such as oral steroids).

When comparing work schedules, researchers grouped participants into:

• Daytime only workers

• Rotating shift workers

• Permanent night shift workers

The highest risk of moderate to severe asthma was seen in women who only worked night shifts.

Dr. Robert Maidstone, the study’s lead author, noted that this is the first study to highlight how asthma risk from shift work differs between men and women.⁽¹⁾

The Menopause Factor: Why Older Women Face More Danger

The findings were even more pronounced among postmenopausal women not using hormone replacement therapy (HRT). This group, when working night shifts, had almost double the risk of developing moderate to severe asthma compared to those working during the day.

This suggests that female hormones offer a degree of protection and when these hormones decline after menopause, women may become even more susceptible to asthma caused by circadian disruption.⁽²⁾

What Can Night Shift Workers Do?

If you're a woman working night shifts, especially if you have a personal or family history of asthma, it’s crucial to be proactive about your health. Experts recommend the following:

• Monitor your breathing: Don’t ignore symptoms like persistent coughing, wheezing, or shortness of breath.

• Schedule regular check-ups: A healthcare provider can help track your lung health over time.

• Discuss concerns: Talk to your doctor about how your work schedule might be affecting your health.

• Adopt healthy habits: Prioritize good sleep hygiene, eat a balanced diet, and manage stress levels to support your overall immune system.

Currently, there are no specific asthma prevention guidelines tailored for night-shift workers, but awareness and early intervention can make a big difference.

Final Thoughts

The world may never sleep, but our bodies were designed to. For women, particularly those working through the night, this new research is a wake-up call. Understanding the hidden health risks and taking steps to protect respiratory health can help night-shift workers stay safe, strong, and informed.

References:

1. Maidstone RJ, Ray DW, Liu J, Bowden J, Rutter MK, Durrington HJ. Increased risk of asthma in female night shift workers. ERJ Open Research. 2025. doi:10.1183/23120541.00137-2025

2. Kai Triebner, “Menopause as a predictor of new-onset asthma: AÂ longitudinal Northern European population study”, Journal of Allergy and Clinical Immunology, Volume 137, Issue 1, 2016, Pages 50-57.e6, ISSN 0091-6749, https://doi.org/10.1016/j.jaci.2015.08.019.

(Rh/Dr. Hansini Bhaskaran/MSM)