. 2021 Jan 14;7(1):e05957. doi: 10.1016/j.heliyon.2021.e05957

Table 3.

Vitamins with their sources and their roles in immune systems.

Vitamins	Sources	Functions in immune system	References
Vitamin-A	Carrots, sweet potato, oily fish, papaya, cheese, egg yolks, tofu, seeds, nuts, liver, legumes and whole grains.	Supports T-cells to find pathogens	British Nutrition Foundation (2020) Clare-collins,(2020)
Vitamin-B₆	Egg yolk, cereals, legumes, fruit, nuts, and fish, chicken and meat, leafy vegetables, such as banana, avocado and green pepper.	Helps to produce new immune cells and neuronal communication. Metabolize antibodies.	Keil et al. (2016) Clare-collins, (2020)
Vitamin-B₉	Nuts, green leafy vegetables, seeds and legumes.	Helps in immune development	Keil et al. (2016) Clare-collins, (2020)
Vitamin-B₁₂	Eggs, meat and dairy and also in fortified soy milk	Helps to produce new immune cells	Keil et al. (2016) Clare-collins, (2020)
Vitamin-C	Citrus fruits, strawberries, blackcurrants, papaya, kiwi, green vegetables, capsicum and tomatoes.	Helps immune cells to attack pathogens, Helps to clear old immune cells from the site of infection, and Helps to maintain the skin fresh and alive to avoid infection.	Hemila (2003) Hemila (1997) British Nutrition Foundation (2020) Clare-collins, (2020)
Vitamin-D	Oily fish, eggs, fortified breakfast cereals, fortified spreads and fortified dairy products.	It increases the effectiveness of monocytes and macrophages to fight against pathogens.	Nonnecke et al. (2014) British Nutrition Foundation (2020) Clare-collins, (2020)