Keeping your immunity in peak condition and how to prevent getting ill in the first place

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When we think about immunity we often forget about our gut. Seventy per cent of the body’s immune system is in the gut, so keeping it healthy is crucial. Let’s look firstly at probiotics. Probiotics are beneficial bacteria normally present in the digestive tract. They are vital for proper digestion and also perform a number of other useful functions such as preventing the overgrowth of yeast and other pathogens, and synthesizing vitamin K. The probiotics most often used as supplements are acidophilus and bifidobacteria. Cultured fermented foods also contain various types and amounts of beneficial bacterias. These foods include buttermilk, cheese, kefir, miso, sauerkraut, tempe and yoghurt. The digestive tract is known as the gut associated immune system. Incomplete digested foods can result in immune reactions like allergies. Whether you succumb to infections is also linked by your balance of gut flora. Probiotics produce substances which stop harmful bacteria growing. They are nature’s antibiotics. They keep E coli, enterobacteria, staphylococci, salmonella and campylobacter at bay and help prevent food poisoning. But they don’t just stop there – probiotics give pathogenic bacteria a hard time and boost your immune system so are useful in all types of disease from cancer to allergies.

The two main types of good bacteria are acidophilus and bifidobacteria. Acidophilus has antifungal properties that help to reduce blood cholesterol levels, aid digestion and enhance the absorption of nutrients. The flora in a healthy gut should consist of at least 85 per cent lactobacilli and 15 percent coli form bacteria. However, the typical colon bacteria count is usually the reverse. This can result in gas, bloating intestinal and systemic toxicity, constipation and malabsorption of nutrients.

Taking supplements help to combat all of these problems by reintroducing the intestinal flora for a healthier balance. There are many good acidophilus supplements available. Acidophilus products come in tablet, capsule and powered forms. Non dairy formulas are best for those who have dairy intolerance. Acidophilus can die at high temperatures. Keep it in a cood dry place, refrigerate it but don’t freeze it.

Bifidobacteria aid in the synthesis of the B vitamins by creating healthy intestinal flora. These are the predominant organisms in the intestinal flora and establish a healthy environment for the manufacture of the B complex vitamins. When you take antibiotics, the friendly bacteria in your digestive tract are destroyed along with the harmful bacteria. Supplementing your diet can help you maintain a healthy intestinal flora. Unhealthy flora can result in the liberation of abnormally high levels of ammonia as protein containing foods are digested. This irritates the intestinal membranes and in addition the ammonia is absorbed in the blood stream and must be detoxified by the liver or it can cause nausea, a decrease in appetite, vomiting and other toxic reactions. By promoting the proper digestion of foods the friendly bacteria also aid in preventing digestive disorders such as constipation and gas as well as food allergies. If digestion is poor, the activity of intestinal bacteria on undigested food may lead to excessive production of the body chemical histamine which triggers allergic symptoms. So in the coming months if you feel your immunity is low, it is worth taking a daily probiotic supplement. As some of you know I’m not a fan of the probiotic drinks, as they are expensive and the levels of good bacteria in them are low. For those sensitive to dairy foods, they are not suitable and they contain sugar. Eating a diet high in probiotic foods will serve you just as well and these include: leeks, onions, garlic, shallots, asparagus, artichokes, fruit and vegetables and a high soluble fibre diet encourages the right bacteria.

Vitamin D

As the cold and flu season approaches, Vitamin D’s benefits on the immune system function are more important than ever. Medical research shows that maintaining high levels of Vitamin D is one of the best things people can do to help fight off colds and flu. It plays a major role in supporting immune function and is known to be an effective agent against inflammation, which is typically caused by flu and other respiratory viruses. By helping modulate the body’s response to respiratory viruses, it helps prevent dangerous and even fatal build up of fluid in the lungs. Though as yet there is no clinical evidence that supplemental Vitamin D can be considered a flu preventative or treatment, there is ample evidence that low levels of the vitamin are associated with higher incidence of a wide range of serious illnesses, including respiratory infections. In addition, numerous studies have shown that people with high levels of the vitamin appear to be less likely to contract flu and other respiratory viruses. Long recognised as important to bone health and strength, Vitamin D has recently been identified as crucial to almost all aspects of health. Deficiency has been recognised as a global health problem, and has been implicated as a factor in a host of illnesses and disorders including cancer, heart disease, hypertension, diabetes, osteoarthritis and osteoporosis. In addition, low levels of the vitamin have been associated with depression, chronic pain, birth defects, and periodontal disease. Because sun exposure is necessary to stimulate the body’s production of the vitamin, some researchers speculate that the indoor lifestyle and weaker UV rays of winter weather make the traditional cold and flu season even more of a challenge. There are relatively few dietary sources of the vitamin, so without adequate sun exposure deficiency is very common. The Food and Nutrition Board at the Institute of Medicine of The National Academies, responsible for establishing Recommended Dietary Allowances of various nutrients, set an RDA of 200 mgs of Vitamin D per day. That recommendation has been questioned as being insufficient, and in 2008 the American Association of Paediatrics announced a new recommendation that literally doubled the existing RDA to 400 IU per day. The AAP recommends that supplementation begin in the first two days after birth.

Our bodies make natural antibiotics called anti microbial peptides and it is thought that vitamin D increases the production of these. Is it then just coincidence that there are fewer bugs around in the summer than in the winter? Children with rickets (lack of vitamin D) often have more infections. It was first thought that this was due to weakened bones but its more probably down to a lack of vitamin D. Vitamin D is found in fish liver oils, butter, cod liver oil, egg yolks, halibut, liver, milk, oats, salmon, sardines, sweet potatoes, tuna and vegetables oil. Vitamin D is also made by the body in response to the action of sunlight on the skin. Herbs that contain vitamin D include alfalfa, horsetail nettle and parsley. Any intestinal disorders and liver and gallbladder malfunctions can interfere with the absorption of vitamin D and also some cholesterol lowering drugs, antacids, mineral oils and steroid hormones can also interfere with the absorption. The message here is get out in the sunlight, particularly in winter, as much as possible.


I could write a thesis on garlic – it’s my favourite natural food supplement. To me garlic is one of the most valuable foods on the planet. It has been used since biblical times and has a mention in the literature of the ancient Hebrews and Egyptians. The builders of the pyramids supposedly ate garlic daily for endurance and strength. It is a potent immune system stimulant and a natural antibiotic. Garlic contains an amino acid derivative called alliin. When converted to allicin, garlic has an antibiotic effect that exerts an antibacterial effect estimated to equivalent 1 percent of penicillin. Because of its antibiotic properties garlic was used to treat wounds and infection and to prevent gangrene during the first world war. There is also some evidence that it can destroy certain viruses. If you can’t cope with it raw, roasted and stir fried you can take Aged Kyolic Garlic from Quest. The versatility of garlic is amazing: it has antioxidant properties; the sulphur and hydrogen compounds in garlic are potent chelators of toxic heavy metals binding them so they can be excreted. These same compounds are effective protectors against oxidation and free radical damage. Garlic aids in the detoxification of peroxides such as hydrogen peroxide and helps to prevent fats from being oxidised and deposited in the tissues and arteries. Studies on aged garlic extract (AGE) have shown that the aging process boosts the antioxidant potential. AGE protects against DNA damage, keeps blood vessels healthy, and guards against radiation and sunlight damage. If you’re worried about garlic choose an odourless form, like AGE or try chewing parsley.

Vitamin C

Vitamin C is an antioxidant that is required for at least three metabolic functions in the body including; tissue growth, repair of adrenal gland function and healthy gums. It also aids in the production of anti stress hormones and interferon. Studies have shown that taking vitamin C can recede symptoms of asthma and it protects against the harmful effects of pollution, helps to prevent cancer, protects against infection and enhances immunity. Vitamin C increases the absorption of iron, so they are often taken together. As we are unable to make it ourselves, it must be obtained through the diet or in the form of a supplement. Alcohol, analgesics, antidepressants, oral contraceptives and steroids may reduce the levels of vitamin C in the body but smoking causes a serious depletion of this vitamin, more so than anything else. Be careful taking large amounts of ascorbic acid as this can lead to stomach irritation – trying taking non ascorbate acid e.g. magnesium or calcium ascorbate. I’ve never found personally or professionally that vitamin C stops a cold or flu but certainly it’s worth taking 1g daily in the flu and cold season to boost the immune system.


One of the most important factors in preventing flu and colds is hygiene. Contrary to popular belief, viruses are not usually airborne. The two main ways they spread are: firstly, if someone who is infected sneezes or coughs and you come in contact with the virus in the air; and secondly, if you touch an object which may have the virus and you then touch your eyes, mouth or nose. I don’t want you all becoming OCD about hand washing(!) but washing your hands thoroughly can reduce your likelihood of catching viruses by a whopping 35%. It’s common for people to touch their nose, eyes and mouth. Most of these actions are sub-conscious, like licking your tongue for flipping pages of a book or a magazine. As soon as you feel an itch you immediately rub or scratch your eyes. Remember the virus can be anywhere – a door knob, a remote control, phones, computer keyboards, etc. All you need to do is keep washing your hands with soap and water frequently. And most importantly, stop touching your face. Try and wash your hands before handling food and eating, putting on contact lenses, going to the loo, blowing your nose, or coughing and sneezing, touching animals, handling rubbish, smoking, changing nappies and door handles, going into hospital or visiting sick or injured people.


Otherwise known as purple coneflower, this herb has amazing properties. Cells are glued together with the help of hyaluronic acid. Bad bacteria like staphylococci and streptococci produce hyaluronidase which dissolves the “glue” allowing the bacteria to get in to the cell membrane. Echinacea has an active constituent with neutralises the hyaluronidase and stops the bacteria from spreading, leaving the white blood cells to deal with the infection locally. Cell membranes have receptor sites to which viruses attach themselves and each have molecules which block the receptor sites so that viruses cannot become attached. It will also increase the activity of the immune system by activating the coding of T cells. Generally it fights inflammation and bacterial and viral infection and stimulates certain white blood cells. Echinacea is good for the immune system, colic, colds, flu and infectious illnesses. It should not be taken for long periods of time with people with autoimmune disorders, and it’s best not to take it all year round, but now is an excellent time of year to start. Some of my patients swear by it and say they never get ill during the winter. You can buy it in a tincture in drops or in tablets. I prefer the tincture as it’s more potent.

Before you get the flu, general symptoms of an impaired immune system include fatigue, repeated infections, inflammation, allergic reactions, oral thrush and slow wound healing. It is estimated that a healthy adult will catch on average two colds per year – people who have more colds and infections are likely to have some problem with their immune function.

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