Theresa Cheung - 100 Ways to Boost Your Immune System

Nutritional deficiencies:The immune system works best when you keep it supplied with a full range of micronutrients such as vitamins and minerals. A poor diet increases the likelihood of nutritional deficiencies and therefore weakens immunity. (For advice on optimising your immunity through diet choices, see ‘Part Two: Boosting immunity with nutrition’.)

Stress:Chronic stress causes the adrenal glands to secrete higher levels of corticosteroids, which depress immune function. (For advice on boosting your immunity through stress management, see ‘Part Two: Boosting immunity with lifestyle changes’.)

Depression:Research shows that people who are negative, moody, nervous and easily stressed have a weaker immune response than those who are more positive. (For advice on boosting your immunity with a positive attitude, see ‘Part Two: Boosting immunity with a Fighting spirit’.)

Lack of quality sleep:Lack of sleep seems to impair the healthy functioning of the immune system. (For advice on getting a good night’s sleep, see ‘Part Two, pages 92–93’.)

Sedentary lifestyle:Exercise enhances the overall functioning of the immune system, and protects against heart disease, cancer and osteoporosis, as well as being an effective way to relieve stress. Research has shown that people who exercise regularly are less likely to get colds than those who are not active. (For advice on immune boosting and exercise, see ‘Part Two, pages 94–95’.)

Over-exertion:Too much exercise can be as damaging as too little. Over-exertion suppresses T-cell function and other immune responses. (For advice on boosting immunity with a regular, moderate exercise plan, see ‘Part Two, pages 94–101’.)

Weight gain:Obesity increases the risk of cancer and heart disease, so maintaining a healthy body weight is a sensible way to encourage long-term immune health, as well as general well-being. (For advice on boosting immunity through weight management, see ‘Part Two, pages 102–103’.)

Alcohol, cigarettes and drugs:Alcohol in excess, together with smoking and taking recreational drugs are simply not compatible with a healthy immune system. The odd drink now and again is fine, but more than one drink a day depresses the immune system; drug use is a major cause of poor nutrition, which damages immunity further; and cigarette smoke contains high levels of dangerous chemicals, including cadmium, which is a powerful immune system depressant. (For advice on quitting smoking, see ‘Part Two, page 126’.)

Over-use of antibiotics:Over-use of antibiotics can cause unintentional suppression of normal immune system responses. (For advice on the sensible use of antibiotics, see ‘Part Three: Fighting Infection’.)

Environmental pollutants:All of the following three categories can compromise immunity and although it is impossible to avoid them completely, sensible use and taking the recommended precautions are advised.

Radiation: From mobile phones, televisions, microwaves, radio transmitters and computers.

Chemicals: From engine exhaust fumes, pesticides, herbicides, smoke, aerosols, paints and household products such as air fresheners, cosmetics, deoderants, detergents and furniture polish. Food additives, preservatives and colourings also fall into this category.

Biological: From house dust, dust mites and mould.

(For advice on avoiding environmental pollutants that can compromise immunity, see ‘Part Two, pages 146-167’.)

The earlier you recognise the signs and symptoms of weakened immunity, the faster you can take corrective action and decrease your risk of illness or poor health. Your immune system may be invisible but there are ways to tell if it is in trouble. Use the checklist below to see if your immune system is in need of a boost.

Do you feel as if you have lost your energy or get-up-and-go?

Do you feel the cold more than other people?

Do you get more than two or three colds a year?

Have you noticed a loss of libido?

Are you overweight?

Do you smoke?

Is your job sedentary?

Do you spend little time in natural sunlight?

Is your diet high in sugar and refined processed foods?

Do you feel stressed, up and down or just below par?

Are you forgetful?

Is it ages since you had a good night’s sleep?

Do you need coffee or other stimulants to get you through the day?

Is your skin dry or dull?

Do you suffer from indigestion, constipation or bouts of diarrhoea?

Is your neck stiff and sore when you move?

Does your breath smell?

Do you suffer from bleeding gums?

Do you suffer from eye strain?

Do you suffer from frequent headaches?

Can you sometimes hear high-pitched sounds in your ears?

Do you suffer from allergies?

Do you get food cravings or feelings of intense hunger?

Are you prone to thrush or cystitis?

Do your cuts or wounds heal slowly?

Do you suffer from anaemia?

Does your hair lack shine?

Do you often feel fed-up and run down?

If you ticked more than 5 boxes and you can’t find any logical explanation (for example, a stiff neck is to be expected if you slept in a draught; hunger is normal if you haven’t eaten for a few hours and so on), your immune system is definitely in need of a boost. Follow as much of the advice as you can in ‘Part Two: 100 Immune System Boosters’.

If you answered ‘yes’ to only a few questions, your immune system is doing its job well, but it’s still worthwhile reviewing ‘Part Two’ to find ways to turn any ‘yes’ answers you gave into ‘no’ answers.

Danger comes when your immune system is weakened, and invaders remain undetected and start to multiply. Some invaders are so powerful that they trample your body’s immune system, but in the great majority of cases research has shown that making the right diet and lifestyle choices is the most effective way to boost your immunity and protect your health.

Although vaccinations are a good insurance policy against disease, and medications can save lives, the first line of defence against unpleasant illnesses – such as colds and influenza – is to make sure your immune system is as strong and healthy as possible. The 100 immune-system boosters that follow will give you all the information you need to keep your body’s defences strong through informed diet and lifestyle choices. And whether you decide to incorporate one or all 100 boosters into your life, bear in mind that each one is designed not only to keep you as free from illness as possible, but to also help you feel great, look better and live longer.

If you keep your body well nourished with a healthy, balanced diet, you can literally ‘eat yourself well’.

Nutrients are needed for every part of your immune system, and for renewal, repair and defence against infection and illness, so its strength will depend on the quality of your diet. It is therefore important to maintain a healthy, balanced diet that provides an adequate intake of vitamins, minerals and dietary fibre.

But what is a healthy, balanced diet? Studies have shown that the so-called ‘Mediterranean diet’ can offer protection against obesity, heart disease, osteoporosis, cancer and diabetes.