Once we hit our fifties, many people notice that bouncing back from a cold or shaking off fatigue takes a little longer than it used to. That’s because our immune system naturally changes with age, becoming slower to respond and more prone to low‑grade inflammation.
The good news is that how we live our day-to-day lives can make a real difference. From choosing nourishing meals over ultra-processed food to prioritising sleep and minimising stress, our lifestyle choices can help keep our immune systems strong, resilient, and ready to support us well into the years ahead.
To understand more about how to support immunity after 50, we caught up with Dr Olaleken Otulana, GP and Physician at Cassiobury Court, who shared everything you need to know.
Why immunity weakens with age
If you feel like it takes you longer to overcome illnesses as you're getting older, you're not just imagining things. Biological processes that occur with ageing mean our immune systems don't respond to illness as efficiently, as Dr Otulana explains.
"The immune system becomes less efficient because the body produces fewer new immune cells and the ones we already have do not respond as quickly. The thymus (which is what helps develop infection-fighting T-cells) shrinks slowly from early adulthood. Inflammation also tends to rise with age, and this chronic background inflammation makes it harder for the immune system to react. Together, these changes mean infections can be a bit more frequent and recovery can take a bit longer than it used to," the GP says.
How can nutrition support a strong immune system
However, you can give your immune system an extra boost through a healthy, balanced diet that provides the raw materials it needs to function properly. "Foods that have vitamins A, E, C, zinc and selenium help immune cells develop and repair. Fruit and vegetables, nuts, legumes and fish all provide these nutrients in a way the body absorbs well," Dr Otulana shares. "Fermented foods such as kefir and yoghurt support the gut microbiome, which plays a surprisingly large role in how the immune system behaves."
Meanwhile, there are also some foods that are best avoided in order to support a strong immune system. "Processed foods, excess sugar and too much alcohol tend to do the opposite. They can contribute to inflammation, disturb the gut microbiome and make it harder for the body to regulate immune responses," the GP says.
As a health and nutrition coach, I would also strongly advise prioritising gut health in order to support your immune system. Around 70 per cent of the immune system resides in the gut, which means when your microbiome is out of balance, you are likely to be more prone to illnesses and find it hard to overcome them. Focusing on eating a predominantly whole-foods diet, including the recommended 30 grams of fibre a day, will support gut health, while foods like avocado, oats, bananas and leeks are good sources of prebiotics, which feed your friendly gut bacteria.
Lifestyle habits that strengthen immunity
It isn't only your diet that will impact your immune system, but also other lifestyle choices, including sleep and exercise. Dr Otulana explains: "Good sleep, regular movement and stress management make a difference. Sleep is when the body restores itself. Moderate exercise improves circulation and helps immune cells move around the body more effectively. Managing stress is very important as long-term high cortisol levels can weaken your immunity."
The role of supplements
You may also consider adding some carefully-selected supplements to your daily routine. However, they shouldn't be used as a substitute for a healthy lifestyle. "Supplements can be useful when someone struggles to meet their nutritional needs through food alone. This may become more common with age," the GP tells HELLO!. "Vitamin D is the main one worth considering in the UK, as it's a hard vitamin to get from food alone. Omega-3 and vitamin B12 may help in specific circumstances, but they are not a replacement for a varied diet."
But don't start using lots of different supplements without checking that they are needed. "It is worth checking levels or discussing options rather than taking a long list of supplements if you are not sure you need them."
The connection between immune health and hormones
Hormonal changes in midlife, such as those that occur during the menopause, also play a role in immune function and may lead to a weaker immune response to illnesses.
"Hormones influence how the immune system behaves, and this becomes more noticeable during midlife. Oestrogen has a regulating effect on immune cells, so its decline around menopause can contribute to increased inflammation, changes in the gut microbiome and a slightly weaker immune response," the GP says. "Thyroid hormones also are relevant here, as an underactive thyroid can make the immune system a bit slower to react to things. In men, lower testosterone levels can contribute to a similar rise in background inflammation."
Winter immunity tips
Even when your immune system isn't as strong as it once was, there are some simple steps that you can take to avoid succumbing to every cold and virus throughout winter. "Keeping up vitamin D levels (we do tend to need some help with this in winter, so a supplement is fine), staying hydrated and eating meals that focus on your nutritional needs will help," says Dr Otulana.
"Prioritise your sleep, wash your hands and keep your home ventilated. A daily walk, even in cold weather, does far more for immune strength than most people realise. And keeping up to date with seasonal vaccinations/protections when the immune system is under more pressure."
In the UK, the annual flu vaccination is recommended by the NHS for adults aged 65 or over, while the winter COVID-19 vaccination is available for free for adults over 75.