The tissues and cells of your immune system work hard to protect you from infection using mechanisms ranging from simple physical barriers to specialised cells that detect and destroy disease-causing organisms. If those mechanisms are weak or functioning poorly, you may feel run down and be more susceptible than usual to minor infections.
What are the symptoms of immune system weakness?
The most common indications of suboptimal immune function are an increased tendency to experience colds, flu, sore throats, sinusitis and other minor respiratory, gastrointestinal or skin infections, and needing more time than usual to recover from them. You may also feel generally unwell or lethargic, and may experience enlargement and/or tenderness of the lymph nodes in your neck, underarms or groin. In people infected with the Herpes simplex virus, an increased frequency of cold sore outbreaks may be another indication that the immune system is weak or run down.
What causes immune system weakness?
Reduced immune system function is sometimes a symptom of underlying medical problems, but is more commonly a consequence of poor diet and lifestyle habits. Key issues to be aware of include:
- Inadequate consumption of nutrients required for normal healthy immune system function may leave you prone to infection. Zinc and vitamin C are especially critical, but many other nutrients are important too, including selenium and vitamin A
- Our immune systems are not fully developed at birth, and as a result, children are more susceptible to colds, flu and gastrointestinal infections than adults are. (For example, they may catch up to 10 colds a year, compared to the 2-4 experienced by most adults)
- At the other end of the lifespan, reduced immune function and increased vulnerability to infection is a common feature of old age, especially among people whose diets are poor. Some researchers have suggested that in many cases, this phenomenon may be at least partially due to low levels of zinc
- Intense or ongoing stress may impede immune system function, increasing your likelihood of developing colds, flu and other respiratory infections
- Regardless of whether it occurs because you’re burning the candle at both ends or because you suffer from insomnia, not getting enough sleep has been shown to increase your susceptibility to cold viruses
- Smoking cigarettes or recreational drugs may make it easier for infections to occur by inhibiting the functioning of the cilia. These tiny hair-like projections line the respiratory tract, where their roles include helping to prevent infectious organisms from entering the body and facilitating the expulsion of mucus and phlegm from the airways so that they don’t become a fertile breeding ground for bacteria
- Similarly, excessive consumption of alcohol may deplete immune system function over time by interfering with the balance of the various types of immune cells in the body and their ability to communicate with each other. Among other consequences, this may increase susceptibility to some infectious diseases, including some respiratory infections
- When you’re already fighting an infection, it’s easier than normal for additional disease-causing organisms to take hold in the body, and as a result, secondary infections may occur. Common examples include bronchitis (which often develops as a complication of a cold) and sinusitis (which often occurs as a complication of hayfever)
- People affected by chronic pain (such as back problems) may also experience reduced immune function
Causes of more severe forms of immune system dysfunction that are beyond the scope of this article and are best discussed with your healthcare professional include:
- Autoimmune disorders (such as rheumatoid arthritis and alopecia), in which the immune system perceives the body’s own tissue as a threat and sets out to destroy it
- The use of certain medical drugs that suppress immune function as part of their mechanism of action
- Genetic issues
- Certain viral infections that lead to severely compromised immunity
From the perspective of traditional Chinese medicine (TCM), a special form of Qi (life force energy) known as Defensive Qi (Wei Qi) is responsible for resistance to disease, but can become depleted or weakened by factors such as inadequate nutrition, insufficient exercise, stress, over work or exposure to excess Wind, Cold or Heat, any of which may make it easier for disease-causing factors such as cold and flu viruses to take hold.
Natural therapies for immune system weakness
Chinese herbs to build resistance to infection
Chinese herbalists have used herbs to enhance Defensive Qi and promote resistance to infection for thousands of years. Herbs traditionally used for these purposes include Qi tonics such as Astragalus, Codonopsis, Ganoderma (Reishi) and Schisandra, which may help to address sub-optimal immune function while improving vitality and energy levels. Siberian Ginseng may also be beneficial due to its ability to enhance resistance to physical, mental and emotional stress, all of which may have negative effects on immune system function. It is often taken in conjunction with Astragalus, and together, these herbs may assist convalescence and recovery from infection.
Probiotic (adults and kids)
The friendly bacteria that inhabit your intestines play a significant role in immune system function, especially when it comes to fighting off invading organisms. However, their fragile balance is easily disturbed by factors such as antibiotic use, stress and poor dietary habits. Taking a probiotic supplement may benefit immune function and reduce the incidence of upper respiratory tract infections, but it's important to choose a formula that contains scientifically-researched bacterial strains with proven benefits for human health. For adults, look for strains such as HOWARU® HN019 and HN001, and FloraFIT® Bl-04. For children, strains of Bifidobacteria such as Bifidobacterium longum BB-536 are more important.
Zinc and vitamin C help maintain healthy immune function
Normal, healthy immune system responses require adequate intake of zinc and vitamin C, both of which are needed for the production and activity of immune cells that help the body ward off infection. Taking a supplement containing zinc and vitamin C may help reduce the frequency with which you catch minor respiratory infections such as colds and flu. When they do take hold, a zinc and vitamin C supplement may also help relieve your symptoms and speed up your recovery. Ideally, choose a formula that contains zinc in a highly bioavailable form such as OptiChel™ZN, which is more readily absorbed and utilised by the body than some other forms of zinc.
Multivitamins provide nutritional support
Taking a multivitamin may help to offset any nutritional shortfalls that occur in your healthy, balanced diet. Selenium and vitamin A are particularly important ingredients due to their importance for healthy immune system function. Alternatively, if you're under a lot of pressure, look for a high-strength formula boosted with theanine (from Green Tea) and alpha-Lipoic acid for additional anti-stress benefits.
Diet and lifestyle recommendations for immune system weakness
- When you’re feeling stressed or run down, it’s sometimes hard to find the motivation to shop for and prepare healthy food, but bear in mind that your immune system and your Defensive Qi require a broad-spectrum of vitamins, minerals and other nutrients in order to thrive, and those are best obtained from a diet that’s rich in fruit and vegetables, and contains healthy sources of protein, fat and carbohydrates
- Spicy, warming and pungent foods are good choices, so make liberal use of garlic, onions, radishes, cinnamon, pepper, ginger and chilli
- Your Defensive Qi may be weakened by exposure to excessive Wind, so try to stay indoors in windy weather, and if you’re venturing out, wear warm, insulating clothes to keep the wind out. (This is particularly important if you’re prone to cold sores, which are often triggered by exposure to wind or harsh sun)
- Toxins from cigarette smoke can impair immunity and damage the airways, so don’t smoke or expose yourself to passive smoking
- Take steps to manage your stress levels. Useful options to consider here may include talking to a counsellor, healthcare professional or trusted friend, ensuring you get adequate exercise (from the perspective of TCM, regular activity is absolutely vital, and Qigong or Tai chi are good choices), and learning a stress-coping tool such as meditation or yoga
- Set yourself up for a good night’s sleep by avoiding the consumption of caffeine in the afternoon and evening, and taking herbs traditionally used to aid restful sleep, such as Passionflower, Albizia and Zizyphus
When should you see your doctor or other health professional about immune system weakness?
- See your healthcare professional if you’re experiencing persistent or repeated infections; in some circumstances they may be an indication of an underlying medical problem
- If you’re concerned that your prescribed medications may be contributing to your immune system weakness, talk to your doctor, pharmacist or healthcare professional