I'm back in the land of the living! I know I'm better because I quite fancy a large glass of wine and a night out. Previously all I wanted was soup and someone to mop my feverish brow. Fortunately, I bounced back in time for the rugby finals so had fun admiring men in shorts slipping around in the mud. It seems Mother Nature took my weather request a little far though … the torrential rain was perfect for upping the mud-factor, but not so perfect for fuzz-free hair. Oh well, with a precautionary tissue in every pocket, it was never going to be a glamorous occasion was it?

This week however I am tissue-free and fighting fit. It seems that those of you who read my tale of woe last week are desperate to avoid the same fate and I've been inundated with questions on flu prevention. I wish I had some magic remedies, but unfortunately I've not got any weird or wonderful cures up my sleeve. If only it was as simple as drinking a cup of rhino horn tea every day, then we'd be laughing. Although the rhinos might not be.

However a sensible tactic would be to holistically nurture your immune system and so this week let's build on the brief tips I gave you last time. Having a strong immune system helps you to resist infection and respond better if you do succumb. Further, this is great general knowledge anyway – useful for battling everything from the common cold to more serious diseases, such as some cancers. In short, boosting your immune system actually has five major benefits:

1. Helps prevent premature ageing

2. Fights off viruses and bacteria

3. Destroys many cancer cells as they are formed

4. Detoxifies your body, and

5. Protects you from exposure to chemicals and radiation

Before we move on to the top tips for boosting your immune system, it's just as important to consider the things that deplete your immune system too. If several of these factor in your life, you need to either work out ways to eliminate them, or follow as many of the tips as possible to help off-set them.

Dietary and lifestyle factors that deplete the immune system include:

¦ Smoking

¦ Stress

¦ Exposure to pollution or radiation

¦ Exposure to carcinogenic chemicals (industrial or domestic)

¦ Drugs

¦Food additives (e.g. colours/flavours/sweeteners)

¦ Excessive salt intake

¦ Excessive sugar intake

¦ High saturated fat intake

¦ Over or under eating

¦ Poor nutritional status (low vitamins, minerals or friendly bacteria)

¦ Existing infections (e.g. fungal infections such as Candida, or worms)

¦ Unhappiness

¦ Negativity

Moving on to the positive steps you can take, try and incorporate as many of these into your lifestyle as possible. Flu or no flu, these steps will have far-reaching benefits both now and in the future.

Boost your immune system – top tips!

1. Exercise

It's well documented that exercise helps to boost the immune system, with both mental (stress relieving) and physical (lymph-draining) benefits. If you've previously been inactive, start out with some gentle walks, but ultimately aim to get some form of good physical activity every day.

2. Eat antioxidant-rich foods

Antioxidants include vitamins A, C and E, the minerals selenium, zinc, iron, copper and manganese, and other nutrients such as lycopene, anthocyanidins, betacarotene and CoQ10. You'll get a good intake of all of these if you eat a wide variety of fruit and vegetables – aim for at least five servings a day. The darker the pigment of the fruit or vegetable, the higher the nutrient content tends to be, so for example berries, spinach and broccoli are more nutrient dense than iceberg lettuce or sweetcorn. Preferably eat them raw or lightly steamed as cooking tends to cause nutrient loss. Raw nuts/seeds, herbs, spices and rooibosch (Red Bush) tea are also extremely high in antioxidants.

3. Avoid nutrient robbers

Caffeine, alcohol, excess salt and artificial additives are all known as "nutrient robbers", depleting your body of nutrients rather than nurturing your system. When you eat or drink something, always have a think about what it's going to do to benefit your body. For example, drinking a diet soda may quench your thirst, but the artificial sweeteners and colourings will have to be detoxified by vitamins and minerals in your body, so ultimately you could end up with a negative nutrient balance. In contrast, drinking water helps to flush toxins from your system, leaving a higher level of nutrients in your body able to do other jobs, such as boosting your immune system.

4. Consider supplementing friendly bacteria

Friendly bacteria in your digestive system (also known as "good bacteria" or "probiotics") pack a powerful immune-boosting punch! These are depleted by caffeine, alcohol, spicy food, refined sugar, infections, antibiotics, some other medications and the birth control pill.

Friendly bacteria are found naturally in "live" yoghurts or cheeses, but a supplement is often more effective especially if you have taken antibiotics or are on the contraceptive pill.

Make sure you supplement a quality brand from a health food store and take them with food, but away from very hot food or drinks.

5. Replace bad fat with good fat

The bad, saturated, hydrogenated or trans fats found in many chips, baked goods, chocolate bars, full-fat dairy products, processed meats and fried foods directly deplete the immune system. On the other hand, good fats (omegas 3, 6 and 9) help to boost the immune system. These are found in fish (not fried!) especially oily fish, raw nuts (almonds, pecans, brazils, walnuts) seeds (pumpkin, sunflower, flax), avocado, olives and unheated oils such as olive/flax. Note that as nuts/avocadoes are calorie-dense, you need to keep portion sizes moderate. Also, when you cook with olive oil, don't heat it so high that it smokes (at which point the fat is now damaged) and never cook with flax/linseed oil over heat (fine for salad dressings.)

6. Detoxify your home

There's often not much you can do to avoid exhaust fumes and other environmental pollutants, but there's a huge amount you can do inside your home. Switch cleaning product brands to a green brand such as Seventh Generation, Greenworks or Ecover. If you must use a chemical product (e.g. mainstream Clorox) then use wipes instead of sprays to prevent the chemicals becoming airborne and triggering respiratory irritation. Avoid mainstream air-fresheners at all costs and use an environmentally friendly alternative such as AirScense (Down to Earth.)

7. Up your hygiene

Flu viruses can live for two to eight hours on surfaces, so make sure you clean yours regularly. As public surfaces may not be as clean as you'd like, try not to touch your mouth or nose unnecessarily. Further, make sure you cover any coughs or sneezes with your hands, elbow or a tissue. Hands should be washed with soap or you can use a hand sanitizing gel. Make sure you dispose of all tissues after first use – no stuffing them up your sleeve!

8. Stay positive!

Chronic high levels of stress are damaging so try and incorporate relaxing exercise and activities into your lifestyle. If you do find yourself going through an unavoidably stressful period, then make sure you ditch the "nutrient robbers" and cram your diet with immune-boosting fruit and veg.

Finally, on a community level, it's important to know when to stay at home. The incubation period for flu viruses is one to four days between exposure and the development of symptoms. The current guidelines from the Department of Health state that you do not need to avoid work unless you start to develop symptoms.

This is tricky however as you will be infectious for one day before getting sick and up to seven days afterwards. If you have recently spent a lot of time with someone who has just got sick, or if you have been caring for a sick family member, you may want to consult your employer before going to work … give them the option! If you do get sick yourself, the guidelines are that you should stay home for 24 hours after your fever has gone, without the use of a fever-reducing medication such as Tylenol. However, let's hope it doesn't get that far. Try including as many of the tips above as possible and boost your immune system as flu season kicks in!

The advice given in this article is not intended to replace medical advice, but to complement it. Always consult your GP if you have any health concerns. Catherine Burns BA Hons, Dip ION is a fully qualified Nutritional Therapist trained by the Institute for Optimum Nutrition in the U.K. Please note that she is not a Registered Dietitian. Contact her at nourishbda@gmail.com