1. Well-balanced diet
A healthy diet is a primary key for better immunity. Vegetables such as broccoli contained high antioxidant properties and happen to be rich in vitamin A, C, and E. An additional vegetable that is recommended for boosting your immunity is Spinach. Spinach is rich in Vitamin C, thus can improve the ability to fight against infection, and boost the immune system of the human body.
An alternative food that you should be including in your diet is citrus fruits. Citrus fruits such as orange, lemon, lime, or grape contain a lot of Vitamin C. Noted that your body does not produce vitamin C on its own, so it is always suggested to consume fruits or supplement that contains vitamin C. 
Ginger is also a key to reduce inflammation and other critical inflammatory illnesses. Gingers are effective at lowering cholesterol levels.
Besides, turmeric contains a high concentration of curcumin, it could decrease any muscle damage, osteoarthritis, or rheumatoid arthritis.
Lastly, yogurt is essential for bone and teeth as well as to fight against certain diseases. It contains a lot of Vitamin D that helps to regulate calcium, phosphorus likewise improving the function of the immune system. 
2. Supplements (Vitamin C / Probiotic)
Supplement such as Immun contains 1000mg of patented, clinically Vitamin C source that can keep you from getting sick. Vitamin C is important in building up a stronger immune system as it can help to fight free radicals in our body. Additionally, vitamin C also acts as a powerful antioxidant that helps maintain healthy blood vessels, skin, bones, and cartilage. 
Probiotic, on the other hand, is a type of supplement that can improve our digestive system. It protects our skin and gut. Therefore, this food and nutrition can be breaking down easily for better absorption.
3. Stay Hydrated
Hydration is very important in maintaining physical wellbeing. It also supports a proper heart rate and proper function of the kidney. Dehydration can cause headaches and hinder a lot of ailments such as kidney stones, headaches, or loss of stamina.  Recommended drinking 1.5L to 2L of water a day depends on your weight.
4. Sufficient Sleep
According to studies , cytokines are released while you are asleep. Cytokines are crucial when you have an infection or inflammation. A lack of sleep will reduce the number of cytokines produced in your body. This could abate the number of infectious antibodies and cells which leads to a poorer immune system. Adults should sleep at least 7 hours every day as per recommendation. 
Stress is another factor that lowers your immunity because stress can promote inflammation across our bodies. It is also a source of imbalance in hormones which leads to an impoverished immune system. In accordance with research, stress can affect our feelings besides behavior.  Therefore, we recommend meditation or exercising consistently to control stress.
6. Engage in physical activity
Exercising can be very beneficial to our health, especially when it comes to elevating our immunity. Exercise improves blood circulation and metabolism rate, which aid in stimulates the immune system.  Furthermore, physical activity such as jogging, swimming is highly proposed to control stress. It puts forward to have at least 3 hours of exercise in a week.
 Schend, J. (2020, April 30). 15 Foods That Boost the Immune System. Healthline. https://www.healthline.com/health/food-nutrition/foods-that-boost-the-immune-system#other-tips.
 Team, the H. E. (2020, April 7). 3 surprising benefits of Vitamin D. Healthline. https://www.healthline.com/health/food-nutrition/benefits-vitamin-d#fights-disease.
 NHS 24, . (2021, May 17). Dehydration symptoms and treatments. Illnesses & conditions | NHS inform. https://www.nhsinform.scot/illnesses-and-conditions/nutritional/dehydration#:~:text=Dehydration%20can%20also%20lead%20to,the%20risk%20of%20kidney%20stones.
 Shoemaker, S. V. (2020, April 1). 9 tips to strengthen your IMMUNITY NATURALLY. Healthline. https://www.healthline.com/nutrition/how-to-boost-immune-health?c=514380530486#8.-Manage-your-stress-levels.
 McCallum, K. (2020, March 23). 5 ways to boost your immune system. Houston Methodist On Health. https://www.houstonmethodist.org/blog/articles/2020/mar/5-ways-to-boost-your-immune-system/.
 Moore, M. (2021, March 30). How vitamin c supports a healthy immune system. EatRight. https://www.eatright.org/food/vitamins-and-supplements/types-of-vitamins-and-nutrients/how-vitamin-c-supports-a-healthy-immune-system.
 Eric J. Olson, M. D. (2018, November 28). Can lack of sleep make you sick? Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/insomnia/expert-answers/lack-of-sleep/faq-20057757#:~:text=During%20sleep%2C%20your%20immune%20system,production%20of%20these%20protective%20cytokines.