What is our immune system?
Our immune system is a complex network of organs, cells, and proteins that work together to defend our body against infection, chemicals, or other foreign substances. The main components of our immune system include:
- Our lymphatic system: An extensive network of vessels that pass through almost every tissue in our body allowing circulation of lymph which contains infection-fighting white blood cells and several other substances
- Bone marrow
- Organs, such as our spleen, thymus, tonsils. Lymph tissue is also present in our intestine.
Our body also has several other “first-lines of defense”, or physical and chemical barriers that limit our exposure to substances and microbes that may cause us harm, for example, our:
- Skin – this provides a waterproof barrier unless broken
- Tears, mucus, and saliva – these all contain enzymes that can fight invading organisms
- Stomach acid – this protects against bacteria and other microbes that have been swallowed
- Stomach bacteria – our gut microbiome plays a crucial role in digestive health and also influences the immune system
- Cilia – these are fine hairs that line the breathing tube and help repel particles away from your lungs
- Urine flow – urine helps eliminate toxins and pathogens from our bladder area.
If a microbe or other substance capable of causing us harm gets past our first-line defenses, then our immune system kicks in. Ensuring both your first-line defenses and immune system are in the best state of health they possibly can be, can help protect you from disease.
Strategies for a healthy immune system
Our immune system relies on a healthy body to function properly. Research has shown that people are more likely to develop certain medical conditions or diseases if they smoke, drink excessive amounts of alcohol, eat a poor diet, don’t exercise, or live with a lot of stress.
The best way to ensure your immune system is functioning at its optimum level to is live as healthy a lifestyle as possible. You can do this by:
- Eating a varied diet, one that is abundant in vegetables, fruits, whole grains, legumes, and uses olive oil, such as the Mediterranean diet. This includes eating less red meat
- Exercising daily, but avoid over-exercise (there is evidence that certain athletes, such as marathon runners, are more prone to disease)
- Getting adequate sleep each night – During sleep our body makes cytokines, which are a type of protein that targets infection and inflammation
- Keep good oral health – Brush your teeth and floss twice daily and see your dental practitioner every six months
- Limiting alcohol intake
- Maintaining a healthy weight
- Not smoking
- Reducing stress – Look at your day-to-day life and see what causes you the most anxiety. If you can’t eliminate it, try to reduce it or find sustainable ways to cope, such as exercising or practicing meditation
You can also protect your first-line defenses by:
- Avoiding pollution and second-hand smoke
- Maintaining good eye health by using eye drops if you are prone to dry eye, treating eye infections, and practicing good eye hygiene particularly if you wear contact lenses
- Moisturizing your skin daily to ensure it doesn’t dry out
- Not touching your face with your hands
- Spending less time in the sun. Although some amount of sun is good for your immune health, too much sun can damage your skin, making it thinner and more likely to break and allow entry to pathogens
- Staying hydrated. Drink at least six to eight glasses of water per day to avoid dehydration and to ensure your body (and skin) don’t dry out. This also helps to keep your urine flow regular, aiding in the removal of bacteria that may have accumulated in your bladder
- Washing and thoroughly drying your hands frequently throughout the day, including after going to the toilet, before eating, and after attending to others who are sick
Every one of these measures helps your immune system to function properly.
Can supplements boost your immune system?
So far, research has failed to prove consistently that a single food or natural remedy can boost the immune system or ward off disease. However, conducting research in this area is difficult, because everybody has different background levels of health, and individuals naturally react differently when exposed to the same organism or substance. It may be possible that some supplements or lifestyle practices do actually help, especially in people who are deficient in these substances. But they may be detrimental for some people, for example, those who are critically ill.
Rather than “boost” your immune system, your goal should be to ensure it is functioning at its optimum level. In fact, boosting the immune system is not beneficial, as it would mean your immune system is overactive, and this is why some people develop allergies or autoimmune diseases.
The best way to ensure your immune system is functioning at its optimum level is to ensure you are following all the strategies for a healthy immune system, as listed above.
If you are considering taking a supplement, talk to your doctor first, especially if you already take other medications. Sometimes you may need to try a supplement for a few months before deciding whether it works for you or not. Supplements that have been marketed for immune support include:
- Bovine colostrum
- Coenzyme Q10
- Omega-3 fatty acids
- Probiotics, such as those containing certain Lactobacillus and Bifidobacterium strains
- Vitamin C
- Vitamin D
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