In this article:
- Habits That Boost Immunity
- Types of Immunity
- What Food Items Boost Immunity Levels?
- Which Vitamins Help in Boosting the Immune System?
- Final Word
Immunity is defined as the body’s internal mechanism to identify and defend itself against foreign bodies such as disease-causing microorganisms and cancerous cells. This biological function is carried out by the immune system.
The immune system is basically made up of billions of cells that flow through the blood and move in and out of tissues and organs to scavenge germs, toxins, or any other foreign substance that poses a health risk. (1)
In this article, you will learn how to improve or strengthen this immune response through simple lifestyle measures.
Habits That Boost Immunity
Incorporating the following lifestyle and dietary habits can help improve your overall immunity:
1. Body hygiene
Good hygiene habits such as frequent hand washing, using hand sanitizer, and wearing a mask if you or others are sick can help prevent the spread of infection and reduce illness. (2)
Washing your hands is important following washroom use as well as before and after sneezing, handshaking, and touching surfaces that are frequently touched by others such as door handles.
Regular vaccinations are crucial to kick-starting the immune system’s ability to protect the body from various bacterial and viral pathogens. If you are unvaccinated, the body will take at least 2 weeks to mount an effective immune response against the contracted illness.
Plus, healthier individuals tend to have a more effective immune response. An effective immune response against various pathogens is likely seen in healthy individuals compared to the immunocompromised and elderly individuals. (3)
Vaccinations prevent infectious diseases from spreading from one person to another. Vaccinations cut the 14-day time period by introducing particular pathogens without causing an infection, resulting in memory immune cells and subsequent robust immunity.
Even though vaccinations are safe and effective for the majority of the population, they can elicit adverse reactions in susceptible individuals. Therefore, it is important to consult your doctor to determine if vaccinations are a suitable option for you.
Proper fluid intake is essential for strong immunity and good health. Your body needs water to maintain the proper functioning of various organ systems.
Dehydration can negatively impact the body; it can result in weakness and mood alterations and can severely affect the renal and cardiovascular systems. Dehydration also has the propensity to cause illness. (4)
Furthermore, sugary beverages can hinder the effectiveness of the immune system, so limit your consumption of sugary foods and drinks. In sum, staying hydrated is essential to boost immunity.
4. Watching sugar intake
It is vital to limit sugar intake, which is correlated with obesity. Sugar is known to cause inflammation within the body and consequently can cause several chronic health-related issues such as obesity, type 2 diabetes mellitus, and heart disease. All these chronic health conditions contribute to weakening immunity.
Therefore, weight loss can aid in reducing inflammation, ultimately reducing the likelihood of future chronic health care conditions. A study found that increased intake of glucose, fructose, honey, or sugar revealed suboptimal functioning of the white blood cells for a duration of five hours. (5)
5. Sunlight exposure
Sunlight provides a good source of vitamin D. Exposure to sunlight can help fight against certain health conditions such as depression, heart disease, and some types of cancer.
The amount of sunlight one should receive varies. On a hot and sunny day, lighter-complexioned individuals only require approximately 10 minutes of sunlight a day.
Sunlight in moderation is important to prevent adverse effects such as a negatively impacted immune system that can potentially result in skin cancer. (6) That said, you also need to protect your skin from the harmful UV rays of the sun, which can cause a lot of cellular damage and pave the way for disease.
The best way to do so is to apply good-quality sunscreen to the exposed parts of your body during the day, but especially before stepping out in the sun. Make sure the sunscreen is broad spectrum, which means it provides protection against both UVA and UVB rays, is water resistant, and has an SPF of 30 or higher.
Plus, spending time outdoors can positively impact your immunity and overall health. Nature has been shown to markedly improve one’s mood, reducing blood pressure and inflammation.
A study published in Frontiers of Psychology found that certain plants release compounds that positively contribute to overall health. (7) These aforementioned compounds released in the air can improve blood pressure.
Natural environmental stimuli such as smell and sounds activate the parasympathetic system, which plays an important role in immune health.
Studies have revealed that moderate exercise can ultimately boost your immune system. (8) Exercising also lowers inflammation, which can aid in stronger immunity. Exercising may help regenerate healthy immune cells.
Additionally, exercising increases blood circulation, which enables the immune system to work effectively. Physical exercise releases endorphins, reducing pain and increasing the feelings of pleasure which can be a stress management strategy resulting in boosted immunity.
A study published in Frontiers of Immunology indicated fewer incidences of acute and chronic illnesses in active individuals that practiced routine moderate exercises often. (9)
The Centers for Disease Control and Prevention (CDC) recommend adults incorporate a minimum of 150 minutes a week of moderate exercise. For high-intensity exercises, 75 minutes a week is the minimum requirement. (10)
There are several exercises that can be implemented in a daily routine such as:
- Brisk walking
Additionally, a study published by the Journal of Medical Association found that taking a greater number of steps daily resulted in decreased chances of dying prematurely from any cause. This study included individuals over the age of 40. Individuals that took 8,000 steps a day had less chances of dying prematurely. Individuals who took 12,000 steps and more had the added benefit in terms of longevity. (11)
Moreover, individuals who strength train at least twice a week have boosted immunity. This translates to stronger bones, controlling disease progression, and improving the body’s ability to process foods. A study published by Clinical and Experimental Medicine suggested that exercising as well as strength training boosts immunity. (12)
7. Dietary changes
Consuming plant-based foods such as vegetables, legumes, nuts, seeds, and fruits provides substantial nutritional value and antioxidants to the body, in turn, promoting stronger immunity to fight against pathogens.
Antioxidants are particularly important to fight off free radicals, which are reactive molecules that build up inside the body and cause inflammation. Excessive inflammation in the body can lead to major health-related issues such as heart disease, Alzheimer’s disease, and some types of cancer. So foods that are rich in antioxidants are a must-have for stronger immunity and better health.
Incorporating whole plant-based diets daily that are high in fiber can also boost immunity. (13) High-fiber foods are essential for the nourishment of the microbiome in the gut. A strong gut can aid in boosting immunity by preventing pathogens from making entry via the digestive tract.
Foods that aid in stronger immunity include:
- Healthy fats, such as olive oil
- Omega-3 fatty acids, such as salmon and chia seeds
- Brown rice
- Probiotics: kombucha, kvass, kimchi, yogurt, tofu, miso, soybeans, and tempeh
8. Cutting back alcohol and smoking
For a boosted immunity, reducing the number of alcoholic beverages and cigarette smoking is crucial.
Chronic alcohol consumption is known to lower immune function, leading to several health-related issues. When there are high levels of alcohol in your body, the body spends most of its time eliminating the agent rather than focusing on the proper functioning of the immune system.
A study published by Neuro-Psychopharmacology & Biological Psychiatry determined that consumption of alcohol for a long period can hinder the function of B and T cells. (14) This results in a weakened ability of the immune system to fight off infections and delayed healing time. Consequently, these individuals have a higher propensity for ailments such as acute respiratory distress syndrome, pneumonia, liver dysfunction, and cancer.
The Centers for Disease Control and Prevention (CDC) recommend consuming only one drink a day (4 oz) for women and two drinks a day for men. The presence of toxins in your body decreases immune function. For this reason, smoking cigarettes is not beneficial for the immune system to work effectively.
According to a review published in Oncotarget, there are several toxins that are released from cigarettes that are harmful to the body. These toxins suppress the growth and function of B cells and T cells responsible for optimal immunity.
Therefore, for boosted immunity, refrain from smoking entirely and exposure to secondhand smoke. (15)
9. Enough sleep
Sleep is crucial for optimal immunity; during sleep, cells are repaired and regenerated. Additionally, sleep promotes the regulation of immune cells such as cytokines, T cells, and IL12. Therefore, getting sufficient sleep may boost immunity.
A study published in Behavioral Sleep Medicine found that individuals that were young and healthy and have no history of sleep-related issues were less likely to exhibit the flu following vaccination compared to young and healthy individuals who had a history of sleep-related issues. (16)
Poor or inadequate sleep has been associated with an increased propensity to illnesses. Lack of adequate sleep can increase cortisol levels, resulting in inflammation in the body, which impacts immunity.
A study found that individuals that slept longer than six hours a night were less susceptible to sickness such as the common cold compared to individuals who slept less than six hours a night.
Sleep hygiene can be incorporated to aid in good quality sleep. Some sleep hygiene tips include the following:
- Sleep in a dark room.
- Observe a strict time to go to bed.
- Do not use electronics in bed 2–3 hours before bed.
- Avoid daytime naps.
- Have a meal 4 hours before your bedtime.
- Exercise regularly during the day.
- Lower the temperature in the bedroom.
- Practice aromatherapy.
- Journal before bed.
- Read before bed.
- Practice yoga and meditation.
- Listen to calming music.
- Limit coffee intake.
- Consume soothing drinks before bed.
10. Staying positive
Stress is attributed to a weak immune system as chronic stress can increase inflammation within the body. Chronic stress increases cortisol levels for a long period, which can hinder the immune system’s ability to effectively work, leading to increased susceptibility to various bacterial and viral infections. (17)
Chronic stress can also lead to complications in health such as anxiety, depression, sleep disorders, weight gain, digestive issues, and impaired memory and concentration.
Thus, stress management is essential for boosting immunity. A study published in the Journal of Health and Social Behavior reported the significance of nurturing relationships, which result in stress reduction. (18)
Several other stress-relieving methods include:
- Visiting a licensed counselor/therapist
Types of Immunity
Immunity in the human body can be characterized as two types: adaptive immunity and innate immunity.
1. Adaptive immunity
Adaptive immunity is the production of antibodies and can be further categorized as active and passive immunity. Active immunity is the ability to recognize, fight, and protect against foreign pathogens such as bacterial, viral, and fungal invaders by the production of antibodies. (19)
Passive immunity occurs when antibodies to disease are provided that are not produced by your own immune system. (20)
2. Innate immunity
Innate immunity, unlike adaptive (acquired or specific) immunity, refers to the immunity that is developed in utero and present during birth. (21) Examples of innate immunity include physical and biological barriers such as skin, gastric acid, mucus, sweat, cough reflex, eyelashes, saliva, tears, and cellular and humoral defenses.
What Food Items Boost Immunity Levels?
Foods that boost the immune system include:
- Citrus foods, such as oranges
- Bell peppers
- Omega-3 fatty acids, such as salmon and chia seeds
- Green tea
- Seeds and nuts
- Dark chocolate
- Sweet potatoes
Plant-based foods such as vegetables, legumes, nuts, seeds, and fruits provide substantial nutritional value and antioxidants, in turn providing stronger immunity to fight against pathogens. (22)
Which Vitamins Help in Boosting the Immune System?
- Vitamin C
- Vitamin A
- Vitamin B6
- Vitamin B12
- Vitamin D
It is important for the immune system to be optimally stable as an overactive and underactive immune system can be consequential to your health.
An overactive immune system can cause allergies and result in autoimmune disorders. An underactive immune system, also known as immunodeficiency, can increase the risk of acquiring infections.
A wide range of factors can contribute to an underactive immune system such as hereditary etiologies, acquired iatrogenic conditions, and underlying diseases. A healthy lifestyle is the best way to build immunity, but it is a gradual process, so be patient and consistent with your efforts.
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