Why your body needs different support now – and how nutrition helps you stay well all season
Winter is approaching, and for many people over 40, this time of year can bring more than cosy evenings and seasonal routines. It can also bring more colds, slower recovery, increased fatigue and a general feeling that your immune system is not as strong as it once was.
If that sounds familiar, you are not alone.
Our immune system naturally changes as we age, and these shifts mean we need more targeted support. The good news is that nutrition and simple lifestyle changes can dramatically improve how resilient we feel during the winter months.
Let’s explore what is happening in your body after 40 and what you can do to strengthen your immune defences naturally.
Why Immunity Weakens After 40
1. Hormonal changes
Oestrogen and testosterone play a quiet but important role in immune regulation. As these naturally decline, the immune system becomes more reactive to stress and slower to respond to infections.
2. Gut health becomes more influential
Around 70 per cent of the immune system sits in the gut.
After 40, gut function often changes due to stress, reduced digestive enzymes and shifts in the microbiome. A compromised gut can weaken immunity and increase inflammation.
3. Nutrient absorption decreases
Key immune-supportive nutrients such as vitamin D, magnesium, zinc and B vitamins are often lower in people over 40 because the body absorbs nutrients less efficiently.
4. Higher stress load
Busy lives, work pressure, family commitments and sleep quality all influence immunity. Chronically elevated cortisol weakens the immune response.
Nutrition Foundations for a Stronger Winter Immune System
Strengthening immunity after 40 is not about supplements alone. It begins with everyday nutrition that supports energy, hormones and gut health.
1. Prioritise protein at every meal
Protein supports antibody production and stabilises blood sugar so the immune system can function effectively.
2. Increase fibre for gut strength
Aim for at least 7–10 different plant foods each day. Fibre feeds beneficial bacteria, which play a central role in immune resilience.
3. Support vitamin D naturally
Vitamin D is essential for immune regulation. Include oily fish, eggs and fortified foods, and consider testing your levels as many adults over 40 are deficient.
4. Eat healthy fats daily
Olive oil, nuts, seeds and oily fish help reduce inflammation and support cell repair, which is crucial during winter.
5. Reduce sugar and refined carbohydrates
These create blood sugar spikes that weaken the immune system, increase inflammation and deplete key nutrients.
Lifestyle Supports That Elevate Immunity
1. Prioritise restorative sleep
Quality sleep strengthens the immune response and supports hormone balance.
2. Manage stress strategically
Short daily practices such as breathing exercises or walking help regulate cortisol, improving immunity.
3. Stay warm and hydrated
Mild dehydration and cold exposure place added stress on the body, making it more vulnerable.
You Can Strengthen Your Immune System at Any Age
Your body is not working against you.
It simply needs different support than it did in your twenties or thirties. With the right nutrition and lifestyle choices, you can build a stronger immune foundation that carries you through winter with more energy, stability and confidence.
If you would like personalised support to improve immunity, energy and overall wellbeing after 40, I would be delighted to help.
Warmly,
Milvia Pili FNTP
Functional Nutritional Therapy Practitioner
