Written by Dietitian Wendy Stevens
Start Now To Beat Cold And Flu Season
How Diet Can Strengthen Your Immunity...
If you want to avoid those winter ills, NOW is the best time to start. A good diet is essential to your immune system and can reduce your risk of colds and flu.
Did you know? A whole food diet rich with antioxidants, phytochemicals, vitamins and minerals strengthens immune function, protects our cells from damage and promotes healing.
Fruit and vegetables are the most potent form of these valuable nutrients but only 7% of Australians eat the recommended 5 serves of veggies and 50% eat 2 serves of fruit per day. So what changes can you make today to have a healthier winter this year?
Vegetables and Fruit
Focus on increasing your intake of the following foods to boost immunity and your health in general.
Vitamins A, C & E are powerful antioxidants that are essential for immune function and work best in combination. To maximise nutrients choose a variety of brightly coloured fruit and veg and eat the skin where possible.
Carrot, spinach, sweet potato, pumpkin are high in beta-carotenes that are converted to Vitamin A in the body. Vitamin A is needed for healthy cells in the immune, digestive and respiratory systems and is essential for iron transport and thyroid function.
Vitamin C stimulates the immune system, reduces infections and supports healing. Good sources are berries, citrus, capsicum, kiwifruit, and dark leafy greens like broccoli, spinach, bok choy and kale.
Wheatgerm, olive oil, seeds, nuts, oats and avocado contain vitamin E which has immune and anti-inflammatory properties. Garlic, onion, leeks and chives contain antibacterial and anti-viral compounds. Herbs and spices are also high in anti-oxidants and have immune-boosting properties e.g. rosemary, turmeric and ginger.
Dose up now on fruit and veg to avoid reaching for the cold and flu meds later!
Where Can You Fit An Extra Serve In?
- Tomato, spinach, avocado and mushroom go well with poached eggs for breakfast
- Hummus, pesto, guacamole and tahini are good snack options full of nutrients and flavour
- Nourishing comfort foods like soups and stews are a good opportunity to add extra veggies in the cooler weather and great for lunches or leftovers.
Aim for 2-3 serves per week of salmon, sardines, mackerel or tuna for the immune-boosting benefits of omega 3s (good fats) and vitamin D. Omega 3’s are needed to form immune cells and also reduce inflammation in the body. If you don’t eat fish regularly a supplement is recommended. Vitamin D is also important for bone and muscle strength and associated with reduced risk of cancer, diabetes, allergy and other auto-immune conditions. Up to 50% of Australians living in our southern states are vitamin D deficient by the end of winter. Safe sun exposure is recommended to maintain levels but if you avoid the sun or are over 60 a supplement may be required.
Minerals, Your Natural Source
Protein. Adequate protein is essential for production of the antibodies produced by the immune system to destroy bacteria and viruses. High protein foods such as red meat, liver, kidney and oysters also have the highest content of the immune promoting minerals zinc and iron. Other types of meat including fish, legumes, egg and dairy are lower in these minerals but are still excellent sources of protein.
Probiotics and Fermented Foods
The healthy bacteria in our digestive tract is a vital part of the immune defence system. If the bacteria is out of balance we are at increased risk of illness. Probiotics can boost this good bacteria. In fact, taking a quality probiotic supplement has been shown to reduce the frequency of colds and gut infections by 40%.
Not all probiotics are the same. Specific strains of this good bacteria support different health needs and probiotics must be of sufficient strengths to have an impact. If you have a sensitive gut you may also need to be careful which probiotic you choose. Talk to your health professional about the best strains of probiotics for your personal needs. Natural probiotic sources include yogurt, kefir, kombucha, sauerkraut, miso and tempeh. While these natural probiotics are a great addition to a healthy diet, most people do not eat sufficient quantities to supply the good bacteria the body needs.
Eating a good range of fruit and vegetables is also essential to provide the nutrients the good bacteria need to flourish and establish in our gut. These nutrients that feed the good bacteria are known as pre-biotics.
Safety With Supplements
While increasing natural food intake of nutrients is safe and highly recommended, caution is advised with certain supplements. Some supplements can build up to toxic levels in the body.
- Excessive vitamin D, iron or zinc supplements can damage the liver, heart and kidneys
- Vitamin A supplements should be avoided in pregnancy due to a risk of birth defects
Not All Supplements Are Equal
Cheaper formulations are often in forms that are poorly absorbed, which can cause digestive upset or in doses that are too low to have an impact.
Beware of Interactions
- Some minerals compete for uptake and other nutrients can interact with each other or prescription medications
- The contraceptive pill, aspirin, blood pressure and reflux medications are some examples of medications that can cause nutrient deficiencies
If you would like more advice on how to boost your immunity before winter or a general diet check-up, book an appointment with a nutrition professional.