Dietary Cold Prevention 101

Dietary Cold Prevention 101

Whether it’s trying to avoid COVID-19 or just stay well this cold & flu season, we have all of the evidence-based recommendations to keep your immune system in check without all of the BS.

  1. Vitamin C

The health benefits of Vitamin C have been long reported and evidence suggests how it may boost your immune system. Lucky for us, the cooler months are when our high vitamin C fruits come into season. Citrus fruits such as Mandarins and Oranges are perfect this time of year. Also, Kiwi Fruit and Strawberries provide a concentrated hit of Vitamin C in their small little tasty packages.

  1. Zinc & Olive Leaf Extract

There is evidence to show that supplementation with zinc & olive leaf extract within 24hrs of the first symptoms of cold and flu can decrease your symptom severity. If you are an athlete please ensure that your supplements are safe from banned substances by seeing a Sports Dietitian.

  1. Probiotics

Probiotics are living microorganisms that can influence our gut bacteria balance. There have been several studies that look at the impact of probiotics on immunity. They may indirectly assist your immunity, specifically the incidence of upper respiratory tract infections.  Although naturally found probiotics such as in fermented soy products, dairy and vegetables (e.g. tempeh, yoghurt and sauerkraut), can be used as a top up or additional support. Probiotic supplementation may be particularly beneficial during high-risk periods such as when travelling or during heavy training blocks. Certain strains and doses are required so speak to your Sports Dietitian first.

  1. Water

Dehydration has been found to decrease the rate at which we salivate and decrease the concentration of salivary immunoglobulin A (s-IgA), which is one of the first lines of defence of the immune function on foreign bacteria. Ensuring you are drinking small amounts of water frequently throughout the day is a good start.



  1. Adequate training nutrition

Ensure you are fuelling sufficiently with carbohydrates during training and recovering adequately with protein and carbohydrates post-training. This will help to reduce stress on the body and maintain immune function.

  1. Vitamin D

Vitamin D is a fat-soluble vitamin that influences several aspects of immunity and can reduce the likelihood of becoming sick. Although small amounts can be obtained from food, sun exposure is the most readily available source of Vitamin D. Aiming for a minimum of 15 minutes of sun exposure per day and up to 40 minutes in the cooler months is a good start.

However, some people may be at higher risk of Vitamin D deficiency, including those with dark skin or people who have limited sunlight exposure (e.g. office workers). Remember that Vitamin D supplements should be taken only if deficient and under the guidance of a qualified Medical Practitioner.

  1. Plenty of Fruit and Veg

There is some evidence that various micronutrient deficiencies — for example, deficiencies of Zinc, Selenium, Iron, Copper, Folic Acid, and Vitamins A, B6, C, and E — alter immune responses. Eating a variety of fruits and vegetables of different colours and reducing processed foods can help ensure that you are meeting your vitamin and mineral (micronutrient) needs.

Aim for 2 serves of fruit & 5 serves of vegetables per day as a starting point.