It is no secret that the key to good health is a strong and fully functioning immune system. Without your immune system, your body would soon be open to all sorts of risk factors that could impact your health.

There are numerous risk factors that can impact on our immune system, including stress, poor diet, medicinal drugs (including antibiotics), pollution and environmental toxins that place a huge burden on our bodies and weaken them.

That's why it makes sense to take measures to strengthen your immune system and keep it in tip top condition.

Eat healthily

The efficiency of your immune system is very closely related to your overall diet. For this reason you should eat plenty of fresh vegetables, fruit, sprouts and seeds, as they contain large amounts of antioxidants that boost your immune system and help fight harmful free radicals.

The powerful effects of Vitamin C on the body are well known. Foods high in Vitamin C include kiwi fruit, broccoli, Brussels sprouts, citrus fruit and peppers.

Another way to boost your body's natural defenses is to eat more oily fish, such as mackerel, salmon, and herring. The omega-3 fatty acids present in oily fish shield immune cells against damaging by-products of your metabolism, such as free radicals, and also stimulate several other cells and proteins in your body, which are responsible for destroying infectious pathogens (disease-causing agent).

Probiotics boost infection-fighting antibodies

You should include probiotic foods such as live (those containing friendly bacteria such as lactobacillus or bifidum) yoghurts and yoghurt drinks in your diet.

Latest research findings have revealed that probiotics activate several components of the immune system, including antibodies proteins that identify and neutralise harmful antigens (Ruas-Madiedo P, et al. J Food Prot. 2006;69(8):2011-5).

Canadian researchers from the Department of Pathobiology, Ontario Veterinary College, University of Guelph, revealed that probiotic foods increase the amount of friendly bacteria in the gut and this stimulates your body to produce natural antibodies (Haghighi HR, et al. Clin vaccine Immunol. 2006 Sep;13(9):975-80).

Immune-boosting properties of Vitamin E

In a study conducted recently, Greek doctors from the Agricultural University of Athens looked at the effects of Vitamin E on immunity. They gave Vitamin E supplements to a group of 15 animals for a month and compared the results with another untreated group.

The findings revealed that the animals receiving Vitamin E displayed greater lymphocyte activity immune cells that kill foreign infectious bugs compared to the untreated animals. They also had higher levels of IgA, a very important immune protein that helps eliminate foreign material from your body (Fragou S, Balaskas C, Fegeros K. J Vet Med A Physiol Pathol Clin Med. 2006 Sep;53(7):327-33).

Good sources of Vitamin E are plant oils such as soya, corn and olive oil. Other good sources include nuts and seeds, and wheatgerm (found in cereals).

A protein with immune-boosting properties

A powerful immune-strengthening substance that can help prevent ill-health is lactoferrin, an iron-building protein found in breast milk (colostrum). (Bauer E, et al. Curr Issues Intest Microbiol. 2006 Sep;7(2):35-51). This protein is our very first shield against infection and disease and primary source of immune-system chemicals.

Studies show that lactoferrin binds iron in your blood, keeping it away from cancerous cells, bacteria, viruses and other pathogens that require iron to grow. It also activates very specific strands of DNA that turn on the genes that launch your immune response. That is why breastfeeding is so important in early life.