Australia’s winter in 2025 is shaping up to be warmer than average, with both daytime (maximum) and night-time (minimum) temperatures predicted to be above average across most of the country1. At the same time, above-average rainfall is likely in many interior and central regions, including Queensland, northern New South Wales, and much of South Australia1. This unusual combination of warmth and dampness can still increase your risk of colds, flus, and respiratory illnesses—especially with fluctuating temperatures and indoor crowding.
Now more than ever, maintaining a strong immune system is essential, and Vitamin C plays a vital role in helping your body defend against infections, recover faster, and stay energised through the season.
Why Vitamin C Matters in Winter
Vitamin C (ascorbic acid) is an essential nutrient that our bodies cannot produce on their own. It supports a wide range of bodily functions and is especially important in winter for its role in immune support, antioxidant protection, and tissue repair.
Here’s how Vitamin C can help you stay healthy during the colder months:
1. Strengthens Immune Defences
Vitamin C supports the production and function of white blood cells2, which are essential for fighting infections. It also helps protect these cells from damage, keeping your immune system strong and responsive—especially important when cold and flu viruses are more active.
2. Eases Cold and Flu Symptoms
While Vitamin C may not prevent the common cold, studies show that it can reduce the severity and duration of symptoms when taken regularly3.
3. Fights Inflammation and Oxidative Stress
Winter brings not only viral infections but also indoor air pollution from heaters and fireplaces. Vitamin C’s antioxidant power helps neutralise free radicals and reduce inflammation4, supporting your body’s overall resilience.
4. Promotes Healthy Skin and Faster Healing
Cold, dry air can leave your skin cracked and more prone to irritation. Vitamin C boosts collagen production, promoting skin repair and reducing the risk of infection through damaged skin.
5. Supports Respiratory Health
With winter often triggering asthma and other respiratory issues, Vitamin C’s anti-inflammatory benefits may help alleviate airway inflammation and improve lung function for those with chronic conditions4.
Best Sources of Vitamin C
There’s no need to wait for summer fruits—many winter-friendly foods are packed with Vitamin C. Here are some top choices to add to your shopping list:
Citrus fruits: Oranges, lemons, mandarins, and grapefruit
Berries: Strawberries, blueberries, and blackcurrants
Kiwifruit: Just one kiwi delivers more than your daily Vitamin C needs
Papaya and guava: Excellent sources if available
Vegetables: Red and green capsicum, broccoli, kale, spinach, and Brussels sprouts
For the best results, aim to eat these foods raw or lightly cooked, as Vitamin C is sensitive to heat and water.
Should You Take a Supplement?
While food should be your first source of nutrients, certain groups may benefit from Vitamin C supplements, especially during winter:
People with limited diets (e.g. low in fruits and vegetables)
Smokers (smoking depletes Vitamin C levels)
Those under chronic stress
Individuals recovering from illness or surgery
Older adults with compromised immunity
Important: Before starting any new supplement, speak with your GP to ensure it’s appropriate for you. High doses can cause stomach upset or—in rare cases—increase the risk of kidney stones.
How to Maximise Absorption
To get the most benefit from Vitamin C:
Pair with iron-rich foods: It helps your body absorb iron more effectively (e.g. spinach with lemon juice)
Eat small amounts throughout the day: Your body can’t store Vitamin C, so spread out your intake. The Recommended Dietary Allowance (RDA) for Vitamin C ranges from 15–75 mg for children, 75 mg for adult women, 90 mg for adult men, and 85 mg for women who are pregnant and 120 mg if breastfeeding.5.
Avoid overcooking vegetables: Steam or roast lightly to preserve nutrients
Extra Tips for Staying Healthy This Winter
Along with increasing your Vitamin C intake, here are other simple ways to protect your health:
Stay hydrated: Cold air is drying—drink herbal teas and water regularly
Keep moving: Light exercise boosts circulation and immunity
Prioritise sleep: Rest helps your body repair and defend itself
Wash hands regularly: This is still one of the best defences against viruses
Dress in layers: Staying warm helps your immune system function more effectively
Final Thoughts
This winter is shaping up to be warmer and wetter than usual across much of Australia. By supporting your immune system with adequate Vitamin C, you can better protect yourself and your family from the season’s health challenges. Whether through food or supplements, staying on top of your Vitamin C intake can make a big difference in your energy, recovery, and overall wellbeing.
Need personalised advice or support with winter wellness? Book an appointment with your Qualitas GP today.
References:
[1] The Bureau of Meteorology, Long-range weather 2025, https://beta.bom.gov.au/weather-and-climate/long-range-weather
[2] Carr AC, Maggini S, Vitamin C and Immune Function, Nutrients. 2017 Nov 3;9(11):1211. doi: 10.3390/nu9111211.
[3] Hemilä H, Chalker E, 2023, Vitamin C reduces the severity of common colds: a meta-analysis. BMC Public Health, 2023 Dec 11;23(1):2468. doi: 10.1186/s12889-023-17229-8.
[4] Medical News Today 2023, Vitamin C: Why is it important? https://www.medicalnewstoday.com/articles/219352#why-we-need-it
[5] Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: The National Academies Press. https://doi.org/10.17226/9810. https://nap.nationalacademies.org/read/9810/chapter/7
