The immune system protects the body from illness and disease. This article will discuss the importance of a robust immune system, signs of a weak immune system, and various ways to keep it healthy.
This article has been medically reviewed by Dr. Charles Penick, MD
Immune System Components
The immune system comprises various organs, cells, and proteins that protect the body from foreign invaders such as toxins, bacteria, viruses, and fungi. The immune system is composed of two parts; the innate immune system, which we are born with, and the adaptive immune system, which develops antibodies with exposure to outside invaders.
The adaptive immune system comprises the following organs:
- Bone marrow. Tissue found inside bones.
- Spleen. An organ located in the abdomen.
- Thymus. Two lobes in the front of the windpipe behind the breastbone.
- Tonsils. Two organs at the back of the throat.
- Lymphatic system. Network in the body that carries lymphocytes to the lymphoid organs and bloodstream.
- Peyer patches. Lymph tissue in the small intestine.
- Adenoids. Two glands in the back of the nasal passage.
Identifying the various components of the immune system is key to keeping it healthy.
Weak Immune System Symptoms
There are several potential signs of a weak immune system. Here are some of the most common.
Elevated Stress Levels
Over time, chronic stress could decrease the number of white blood cells in the body, increasing the susceptibility to infections and disease. Studies find social stress can lead to the development of psychological problems ranging from exaggerated anxiety to violent behaviors. Stress increases cytokine levels and contributes to dysregulated immune responses, which might increase the potential for slower wound healing. 
Slow Healing Of Minor Cuts and Scrapes
To heal and protect wounds from further damage, the body sends blood to the area to regenerate new skin. A weak immune system allows bad bacteria to multiply in the area, which could delay or impede the healing process. In addition, fewer white blood cells could be produced with a weakened immune system.
In healthy individuals, it can take the body just a few days to produce the antibodies to fight off colds. On the other hand, a weakened immune system could cause a person to catch colds more frequently, be longer in duration, or more severe.
The gut microbiome plays a key role in the health of the immune system, with 70-80% of immune cells being present in the gut.  An imbalance can occur when bad bacteria outnumber good bacteria in the gut. This could weaken the immune system, increasing the risk for a variety of health issues including indigestion, cramping, bloating, stomach aches and irritable bowel syndrome.
Increased Rate of Infections
Individuals who have frequent infections may have a weak immune system. According to theAmerican Academy of Allergy Asthma Immunology, the following are signs of immunodeficiency disorders in children:
- Need preventive antibiotics to decrease the number of infections
- Has bacterial sinusitis three or more times per year (or chronic sinusitis)
- Have more than four infections per year
- Need four or more antibiotic treatments annually
Each of these may signal an immunodeficiency disorder.
Boosting Immune Health
Keeping the immune system strong is essential. Here are ways to boost immune health naturally.
Studies indicate sleep and the immune system are both associated and influenced by each other. Sleep deprivation makes the body susceptible to infection: researchers note improved sleep habits help to make the immune system efficient and better equipped to fight infections. 
In addition to getting 7-9 hours of sleep per night, naps have an effect on the immune system as well. Midday naps could increase alertness, decrease saliva cortisol levels, and return white blood cell counts to baseline values. 
Sunlight helps to increase the number of white blood cells in the blood and healthy circulation. White blood cells help the body defend itself from harmful bacteria and fight infection. Sunlight also stimulates the production of vitamin D.
Studies on vitamin D indicate a deficiency contributes to susceptibility to infection and increased risk of autoimmune disorders.  Common autoimmune diseases include the flu (influenza), pneumonia, bronchitis, Graves’ disease, lupus, Crohn’s disease, celiac disease, and rheumatoid arthritis.
On average, 10-15 minutes of sun exposure to bare skin daily is enough to obtain adequate vitamin D levels. Note: Longer amounts of sun exposure can be needed during winter months or for those with darker skin. Sunscreen blocks UV rays and should be applied after 15 minutes of exposure.
The keto diet is a high-fat, moderate protein, and very low carb way of eating. Ketosis is a metabolic state your body is in once you’ve efficiently transitioned from burning carbs/sugar for energy to burning fat, and you release fat stores for energy.
When you first started the keto diet and vastly reduced your carb intake, your body kicked into high gear to burn off all your remaining carbs and glycogen stores. Then, when carbs were no longer an option, it began tapping into your excess fat stores for energy. After four weeks or more, your body is getting used to living off of fat, or becoming “fat adapted.”
By eating fewer carbs, the body is forced to use stored fat for energy. In addition, the liver turns the fat into ketones, which are used by the brain and other organs for energy.
The keto diet has been shown to positively affect the immune system: studies indicate it helps increase the amounts of good bacteria in the gut microbiota by reducing levels of intestinal pro-inflammatory T cells.  Chronic inflammation can cause the body’s immune system to attack healthy cells by mistake and lead to a weakened immune system, bringing about more illnesses. So adapted a keto diet or even cycling in and out of ketosis can help with lowering inflammation and therefore boosting immune health.
Benefits of exercise include improved cardiovascular health, shedding excess body fat, and reduced risk of type 2 diabetes. Studies indicate that regular sessions of moderate exercise (up to 45 minutes daily) can help strengthen the immune system with special benefits for older adults and those with chronic diseases. 
Examples of moderate exercises and physical activities include the following:
- Raking leaves
- Skipping rope
- Pushing a stroller
- Swimming laps
Note: Studies indicate extreme exercise often performed by high performance athletes and military personnel could have the opposite effect and potentially suppress the immune system, increasing the susceptibility to infection. 
Immune System Supplements
Some key supplements can help with immune health as well. Here are the top all-natural supplements available fromRevelation Health:
CZI - Vitamin C, Zinc, & Immune Support was specifically created to help boost the immune system. It also contains green tea extract, copper, citrus bioflavonoids, L-Lysine, and hesperidin, powerful ingredients that help strengthen the immune system. This product is gluten free and contains no artificial ingredients.
CytoDefend - Immune Support is a highly concentrated formula that contains powerful extracts that support a healthy immune system:
- Zinc sulfate
- Elderberry fruit
- Echinacea Herb
- Licorice Root
- Bupleurum Root (Chaihu)
- Astragalus Root
- Ascorbic acid
One dropper full per day is all that is needed to support immunity.
The immune system is the body’s first line of defense against illness and disease. Several organs located throughout the body are part of the immune system, including the lymphatic system, bone marrow, and adenoids. Incorporate the tips listed above into your daily life to keep your immune system strong. Consult with your doctor if you have symptoms of a weak immune system.
Medical Disclaimer: This article is based upon the opinions of Revelation Health. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Revelation Health and associates. This article has been medically reviewed by Dr. Charles Penick, MD for accuracy of the information provided, but Revelation Health encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional.
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