It’s that time of year when our thoughts turn to Lemsip, Olbas oil and replenishing our collection of pocket tissues. At the moment, it’s hard to step onto a train carriage or inside an office without hearing a chorus of coughs and sniffles. 

One thing that’s not escaped my notice, though, is that my boyfriend and I are often struck down by infection at completely different times during flu season. And if we do find ourselves being struck down at the same time, our symptoms are often markedly different. It turns out that we’re far from being an anomaly; science suggests that men and women have immune systems that function differently.

The differences in male and female immunity have been thrown into the spotlight after a recent study found that women have a far higher risk of developing long Covid compared to men. The study, published in Jama Network, found that women had a 31% higher chance of developing long Covid than men. However, there were some interesting age-based disparities in the findings.

The paper, which analysed the symptoms of long Covid in 12,276 adults who all had Covid at least six months earlier, found the risk was greatest in women aged 40–54, who had a 48% higher chance of developing long Covid compared to men. Women over 55 had a 34% higher risk of developing the condition, while for younger people (aged 18–39), the difference in risk disappeared between men and women.

Interestingly, as an essay in The Conversation points out, the results contrast with data we already have on Covid infection severity, which finds that men are more prone to developing severe symptoms and are more likely to die from the disease, making up around two out of three Covid deaths.

This confirms what we know about the differences in male and female immune systems. “Women typically have a stronger immune response than men, primarily due to the effects of hormones like oestrogen, genetic differences, and the presence of two X chromosomes,” explains Ian Budd, pharmacist and medical adviser for Chemist4U.

Oestrogen, in particular, plays a crucial role in boosting immune activity by enhancing the function of immune cells. In general, women have much higher levels of oestrogen than men, making women generally more effective at fighting off infections. On the other hand, testosterone, the dominant male hormone, tends to suppress immune responses, which can make men more vulnerable to infections. 

However, women’s heightened immune response can come with its own challenges. It means that women are more susceptible to autoimmune diseases, such as lupus and rheumatoid arthritis, where the immune system mistakenly attacks the body’s own healthy cells. And while a strong immune system helps combat infections, an overactive immune response can lead to chronic inflammation and autoimmune conditions. “This highlights the complexity of immune function and the need for a balanced immune system rather than simply a stronger one,” says Budd.

Natural hormonal changes as women age also impact our immune function. Oestrogen not only enhances immunity but also helps regulate inflammation, so when oestrogen levels drop during menopause, immune defences weaken, making women more susceptible to infections and inflammatory conditions. This decline also means women have an increased risk of developing chronic diseases, such as osteoporosis and cardiovascular conditions, which are closely linked to inflammation.

So what can we do to limit the impact of these hormonal changes and a heightened immune response to make sure we have a balanced immune system that will help us stay healthy throughout our lives?

Pay attention to gut health

“The gut microbiome plays a key role in immune function, helping to regulate inflammation and protect against harmful pathogens,” says Bidd. “However, hormonal shifts can alter gut bacteria, potentially weakening immune defences.” He advises eating probiotic-rich foods, such as yoghurt, kefir and fermented vegetables to help maintain a healthy gut microbiome and strengthen the immune system, as well as a fibre-rich diet with plenty of fruits, vegetables and whole grains.

Exercise regularly

“Regular exercise promotes circulation and immune cell activity, helping the body fight infections more efficiently,” says Budd.  

Monitor stress levels

External influences such as stress levels, lifestyle choices and environmental factors can play a significant role in our immune health. Chronic stress is particularly harmful to the immune system. When stress levels are high, the body produces excessive amounts of cortisol. When this hormone is persistently elevated it can suppress immune function and increase the risk of infections. “Managing stress effectively – through mindfulness, relaxation techniques and regular physical activity – can help maintain a well-functioning immune system and overall wellbeing,” says Budd.

Don’t neglect sleep

“Prioritising sufficient sleep allows the body to repair and strengthen its immune responses while reducing stress further enhances immune resilience,” says Budd.

Get vaccinated

Staying up to date with vaccinations is crucial, especially for women with underlying health conditions. “Vaccines help the immune system build protection against serious infections, reducing the risk of complications,” says Budd.   

Images: Getty