How to build a strong immune system

• Vitamin D has been shown to possess anti-viral properties  Most of us are spending more time indoors at the moment so are missing out on vitamin D from the glorious spring sunshine. Food sources include oily fish (especially wild salmon), eggs and mushrooms. See column on the left for more information about marvellous mushrooms
• Vitamin C provides antioxidant protection to cells. Consume plenty of vitamin C foods daily in the form of vegetables and fruit.  Citrus fruits - lemons, limes, oranges and grapefruit are in plentiful supply. Kiwis and berries - also rich C-sources - are available too.  Leafy greens, including cabbage, spinach, kale and Brussels broccoli  -  whether fresh or frozen -  help to top up vitamin C levels. Chop peppers into a salad or include in a stir-fry of colourful vegetables. You get the message- eat a rainbow everyday!
• Vitamin A is involved in the development of the immune system and protects against viruses. Top food sources are beef, liver, eggs and salmon.  Certain fruits and vegetables contain carotenoids which convert to vitamin A: add red peppers, carrots, sweet potato, spinach, broccoli, mango and dried apricots to your shopping list
• Zinc plays a central role in the immune system. If you want your natural killer cells to be on top form , make sure you consume zinc-rich foods: meat, shellfish, beans pulses, nuts seeds and eggs. My breakfast granola recipe is full of nuts and seeds and low on sugar. You'll also like my pumpkin seed butter recipe,  a delicious savoury spread or use as you would pesto 
• Selenium is an anti-viral hero. Studies show that a lack of this important trace mineral increases vulnerability to infection from viruses. Find it in Brazil nuts, tuna, poultry, beef and pork, cottage cheese, brown rice and lentils. Try this delicious anti-inflammatory lentil soup 
• Gut health An estimated 70% of our immune cells live in the gut. We can feed our immune-friendly beneficial bacteria with prebiotic fibre-rich foods such as onions, garlic and leeks. Also consider bacteria-rich fermented foods, including kefir, kimchi and raw sauerkraut (tip: if you're not used to these foods, start slowly)
• Many of us are worried about the future, our health and that of our loved ones. Psychological stress switches on our "fight or flight" instinct which has an adverse effect on the immune system. Breathing techniques can restore "rest and digest" mode and a feeling of calm. You can use this simple technique anytime, anywhere:
  Empty your lungs of air, inhale through the nose for 4 counts, hold for 4 counts, exhale through the mouth for 4 counts, Repeat until you feel relaxed
• Good quality nutritional supplements can be very helpful for many areas of health, including the immune system. That said, my focus in this newsletter is on nutrients found in food. Supplementation is a tricky and potentially dangerous area, unless you know what you're doing. For example, some nutrients are toxic in high doses or there may be interactions with medication. I check drug and nutrient interactions as part of a nutritional therapy consultation.