Preparing for the cold: boost your immune system!

With the coldest finally setting in, it is important that we do everything in our power to prepare ourselves for the cold (both the weather and winter illnesses). Boost your immune system by considering your dietary and drinking habits.

Nutrition and the immune system

Many factors outside the human body can threaten overall health and immunity. For most of us our busy daily lives are filled with stress, chaos and lack of sleep. These problems lessen the strength of our immune system, the body’s natural defence mechanism, making us more vulnerable to everything from common viruses to more serious illnesses.

The good news is that functional ingredients can help boost immunity and promote healthier lives. As someone who suffers from an autoimmune disease I truly believe that when it comes to diet, what we consume really can really help to strengthen our immune systems and help to fight infections and reduce inflammation.

While the body only has a limited capacity for storing nutrients, there is a continual need to provide good nutrition to maintain optimal immune function.

Boosting immunity – preventing disease

A number of scientific studies have demonstrated the value of overall good nutrition in maintaining a healthy immune system, and also the role of specific nutrients as immune boosters. In addition to its role in preventing infection, good nutrition is also important to help fortify people with persistent disease. It is quite well established, for example, that HIV/AIDS sufferers can benefit in their struggle against infection and physical deterioration by maintaining an optimal level of nutrition.

It should also be an important consideration of expectant mothers as good nutrition to help prevent infection begins in the womb. It is evident that the nutritional health of the mother is vitally important to help fight off infection and provide an optimal environment in the womb for foetal development. Recent studies have shown that adequate Vitamin D may protect against placental infection by boosting innate placental immunity. Good maternal nutrition is also vital for optima maternal antibody production. It is these important antibodies that are passed on to the baby through breastfeeding.

Other vitamins, such as the popular antioxidant Vitamin E, are also important for immunity. Studies in elderly people have shown that high doses of Vitamin E can boost immune response and can reduce the rate of respiratory infections in nursing home residents. Zinc is also an important nutrient that’s been reviewed for its immune properties. Many studies in developing countries have shown the powerful benefits of providing physiological amounts of zinc in reducing child morbidity and mortality associated with respiratory and diarrheal diseases.

Moreover, an abundance of research now exists showing the beneficial effects of probiotics (such as Yakult) in supporting the immune system by promoting gut health. Whilst there is some general controversy regarding their efficacy and the evidence for probiotics remains inconsistent in scientific literature, there are studies showing that daily administration of probiotics can help to maintain a healthy bowel and increase resistance to some common infections.

Immunity boosting nutrients

Some of the nutrients already mentioned plus others which have immunity health claims, and have been shown by scientific studies to influence immunity are listed below.

Nutrient	Effect on immune system	Sources
Carotenoids	May influence immune function by altering functional capacity of innate immune cells, lymphocyte (T-cell) proliferation and delayed-type hypersensitivity response.	Carrots, sweet potato, spinach, eggs, tomatoes.
Vitamin C		Blackcurrants, red pepper, oranges, broccoli.
Vitamin E		Soya, corn and olive oil, almonds, sunflower seeds.
Vitamin A	Important for immune system maturation and B-cell antibody production.	Cheese, eggs, oily fish (mackerel), fortified margarine.
Vitamin D	Provides protection against bacterial infection and has anti-inflammatory properties.	Oily fish and eggs, fortified foods (margarine, breakfast cereal, milk).
Omega-3 (DHA and EPA)	Inhibits production of inflammatory eicosanoids.	Oily fish (mackerel, sardines, salmon, tuna), seed oils, flaxseed.
Copper	These minerals mop up free radicals and reduce inflammation and risk of infection by regulating cells of the innate immune system.	Nuts, shellfish, offal, dark leafy greens.
Zinc		Bread and cereal products, dairy foods, shellfish, meat.
Selenium		Bread, meat, fish, eggs, brazil nuts.