The chances are that either you or someone in your immediate family suffers from, or has suffered from asthma. This inflammatory disease currently affects over 5 million people in Britain and is rapidly on the increase in developed countries. In England, one in four children has asthma compared to one in 18 back in the 1970s and it is now the leading cause of school absenteeism in children under 15. Most experts agree that the grown in asthma is likely to be due to changes in diet, lifestyle or environmental factors, with food allergies being very high on the list of contributors. Yet few sufferers are aware of the impact that diet can have on their condition.

During an asthma attack the airways become inflamed and constricted, making it harder to breathe. This inflammation can result from food allergies, exposure to environmental irritants or a genetic predisposition to inflammation that is made worse by the wrong diet and high levels of stress and anxiety. Often it is a combination of all of these factors. Most medical treatment relies on suppressing the reaction with anti-inflammatory inhaled drugs but do nothing to treat the underlying cause.

The nutritional approach however considers that asthma is triggered when a person's total load exceeds their capacity to adapt. While there may be a specific trigger (such as stress, exposure to a food allergen or cigarette smoke for example), these triggers are just the final straw for the body's immune system, rather than the root cause. The goal therefore is to increase a person's adaptive capacity to lessen the load.

The commonest culprits for food allergy-related asthma are wheat, milk, eggs and soya, while colourings, preservatives (especially sulphites) and other chemical food additives may also be implicated, along with dust mites, mould and animal dander. I always tell asthma sufferers to test for both IgE and IgG allergies, as delayed-onset IgG allergies (often referred to as food intolerances, or 'hidden' allergies) will fly under the radar of standard medical IgE allergy testing. You can do this at home using a simple pin prick blood test that is then sent off for laboratory testing. For more information on IgG antibody food allergy testing click here.

As well as checking for underlying allergies I recommend sufferers increase your intake of antioxidants, as these powerful substances reduce inflammation. Numerous studies have shown that the lower a person's antioxidant intake, the worse their asthma, while a high intake of fresh fruits and vegetables, which boost antioxidant levels, reduces asthma severity. This means gorging yourself on fresh, brightly coloured fruits and vegetables. Eat them raw or lightly cooked to maximise the nutrient content. If you find it a chore to wade through a plate of salad or endless fruit, try juicing or blend fruit smoothies for naturally sweet, nutrient-dense drinks that pack a powerful antioxidant punch. One UK survey of 1,500 asthma sufferers showed that people who ate at least 2 apples per week had a 22-23% reduced risk of suffering from as asthma attack than those who didn't.

My advice therefore is to include plenty of fruits and vegetables in your diet and to supplement a multivitamin and mineral, as well as 1g of vitamin C per day and an antioxidant complex that provides vitamins A, C and E, as well as zinc, selenium and glutathione and/or n-acetyl cysteine. Plus, you would be well advised to take an essential fat supplement if you do not eat oily fish regularly. Omega 3 fats from oily fish (salmon, mackerel, trout, fresh tuna and sardines) reduce inflammation, and a number of studies have found lower rates of asthma in fish eaters. Whereas meat and dairy products are high in arachidonic acid, a type of fat that encourages inflammation, oily fish can actually reduce inflammation and should therefore be consumed regularly. This means eat oily fish two to three times per week or take a supplement (providing around 600mg EPA and 400mg DHA together with 200mg GLA to provide the correct balance of omega 3:6).

Flax seeds can be eaten instead if you do not eat fish, but these need to be converted to get the beneficial fats, and asthma sufferers are often low in the nutrients such as zinc required for the conversion process. A tablespoonful of ground seeds per day (keep a jar of half flax seeds, half a mixture of sunflower, sesame and pumpkin seeds in your fridge) is nonetheless a nutritious addition to cereals, porridge or smoothies, to provide the right balance of omega 3:6 fats. 

Other nutrients that should be included in every asthma-sufferers diet include:

. MSM sulphur - from which anti-allergy amino acids like cysteine and methionine are made. Eat plenty of sulphur rich foods like eggs, onions and garlic and consider supplementing a daily dose of between 1,000-6,000mg MSM

. Quercetin - natural anti-inflammatory found in apples

. Bromelain - natural anti-inflammatory found in pineapples

. Magnesium - regulates the immune system. In nuts, seeds, dark green leafy vegetables and wholegrains

. Zinc - required for turning essential fats from fish and seeds into the anti-inflammatory substances which help reduce allergic potential. In nuts, seeds, wholegrain, eggs, meat, fish and shellfish

. Ginger - common asthma remedy in the West Indies. Turns off the body's inflammatory markers. Add to salad dressings and marinades, sprinkle ground ginger on stewed fruit or porridge or add to juices

. Turmeric - the active ingredient curcumin in the orange spice turmeric has proven highly effective in reducing asthma symptoms. Use in curries or add to rice during cooking for extra flavour and colour. Curcumin also can be taken as a supplement.

Reducing stress, anxiety and exposure to environmental pollutants such as cigarette smoke and traffic fumes will also help to decrease the toxic load on your immune system.

It is not just what you breathe but how you breathe however. Many asthma sufferers find that learning to breathe correctly can be hugely helpful in managing their condition. Most of us breathe very shallowly, but deeper, slower breathing can greatly reduce asthma symptoms as well as helping you to de-stress. Yoga and tai chi both incorporate breathing methods, and the Buteyko method of breathing has been taught to asthma sufferers with great success. The theory behind this technique is that asthma sufferers tend to breathe too fast (more than twelve breathes per minute) and that this causes them to breathe out more than the healthy amount of carbon dioxide. Although we tend to consider this a waste gas, in fact carbon dioxide is vital for the proper functioning of our body's chemistry. A drop in carbon dioxide levels causes blood vessels and airways to constrict for example, which obviously has huge implications for asthma.

Thousands of people have found that breathing training has helped them to control, and even overcome their asthma. If you want to teach yourself this valuable technique I thoroughly recommend you read Asthma Free Naturally by Patrick McKeown . I have also recently come across hand held breathing devices which you use for a few minutes per day to train your lung's inspiratory (breathing) muscles to breathe deeper and more effectively. This is suitable for everyone from asthma sufferers to athletes or the very unfit. Click here for more information.