Boost Your Immunity During Winter:

Practical Tips to Stay Well

Winter brings cooler temperatures, shorter days—and for some of us—a rise in sniffles, fatigue, and lingering bugs. If you’ve noticed that you tend to get sick more often in the colder months, you’re not imagining it. Our immune system is influenced by seasonal changes, and now—with higher humidity from all the recent rainfall—there’s an extra concern: mould.

Let’s explore what you can do to support your immune system this winter, from protecting your indoor air to nourishing your body with the nutrients and habits that keep your defences strong.

The Hidden Threat: Mould and Your Immune System

With ongoing heavy rain and increased humidity, many homes are experiencing excess moisture, a key ingredient for mould growth. Mould spores don’t just damage property—they can impact respiratory health and weaken immune function, especially in those with asthma, sinus issues, or allergies.

Preventing Mould Growth Indoors

Taking proactive steps to reduce mould exposure is essential for immune health:

• Open windows daily to allow airflow and reduce condensation. Even in winter, a short burst of fresh air helps.
• Use a dehumidifier, especially in bathrooms, laundry areas, or bedrooms prone to dampness.
• Wipe visible mould with a damp microfibre cloth and a natural treatment—clove oil diluted in water is effective and low-tox.
• Avoid bleach, as it doesn’t penetrate porous surfaces and may worsen indoor air quality.

Controlling indoor humidity not only supports your respiratory and immune health but also reduces your overall toxic load.

Nutrients That Strengthen Your Immune Defence

A well-functioning immune system depends on specific nutrients that support white blood cell production, inflammation control, and antioxidant protection.

Essential Nutrients to Boost Your Immunity During Winter

• Vitamin D: Often lower in winter due to reduced sun exposure, vitamin D is crucial for modulating immune responses and reducing inflammation.
• Vitamin C: A powerful antioxidant that enhances immune cell activity and shortens the duration of infections.
• Zinc: Vital for white blood cell function and mucosal barrier integrity. Even mild zinc deficiency can impair immune defences.
• Iron: Supports oxygen delivery to tissues and helps the immune system mount an effective response to pathogens.

If you’re unsure about your levels, consider getting tested—especially for vitamin D, iron, and zinc, which are commonly deficient in Australia.

Nourish Your Gut, Support Your Immunity

Did you know that over 70% of your immune system resides in your gut? A healthy and diverse microbiome produces compounds that regulate immunity, inflammation, and even your body’s ability to respond to viruses and bacteria.

How to Feed a Healthy Gut Microbiome:

• Aim to eat a minimum of 30g of fibre daily, from vegetables, seeds, legumes, and whole grains.
• Include prebiotic foods, like garlic, onion, leek, asparagus, and green banana flour. If these foods flare gut symptoms, you likely have gut bacteria imbalance (e.g dysbiosis or SIBO).
• Prioritise colourful plant foods, rich in phytonutrients and polyphenols, which help reduce inflammation and feed beneficial bacteria.

Supporting your gut is one of the most powerful things you can do for long-term immune resilience.

The Power of Sleep and Sunlight

Sleep and sun exposure may not sound like immune boosters, but they are foundational.

• Aim for 7–9 hours of quality sleep, which allows your body to release immune-regulating cytokines thereby improving your immune surveillance.
• Get outside in daylight, particularly in the morning to get some natural light exposure. Sunlight exposure—even in winter—supports your circadian rhythms, immunity and mood. It can also help you to avoid the depressive effect caused by “grey” days (e.g. Seasonal Affective Disorder or SAD).

Lack of sleep and indoor-only living can both weaken immune responses and increase your risk of infection.

Sugar, Starch and Immunity: What You Should Know

Winter often brings cravings for comfort foods, but high intakes of refined sugar and starchy carbohydrates can depress immune function.

Research shows that sugar:

• Suppresses white blood cell activity for up to 5 hours after consumption. If you are already fighting off a virus or are exposed to an illness during this time, this could be a long enough window for illness to set in.
• Increases inflammatory cytokines, which impair effective immune signalling.
• Can feed yeast and unfavourable gut bacteria, disrupting microbiome balance.

Try to minimise highly processed and sugar-laden foods. Instead, opt for slow-release carbs like quinoa, legumes, or cooked/cooled sweet potato paired with protein and healthy fats to keep your blood sugar—and immunity—stable.

Final Thoughts

Winter doesn’t have to mean getting sick. In fact, if you have a robust immune system you should rarely get sick or if you do, the symptoms should be mild and serve as immune system education. Think of it as a “natural vaccine” to increase future resistance to new viral strains. 

Support your body by taking steps to reduce mould in your home, optimising your nutrient levels, supporting your gut health, prioritising your sleep and making sure you get outside (even for a little while each day). These small steps have a synergisting impact  to fortify your immune system naturally.

If you’d like personalised advice on testing your nutrient levels, boosting gut health or creating an immune-supporting wellness plan, reach out for a consultation — I’m here to help you stay well all season long.