Nutritional supplements that support immune health are being talked about a lot lately – particularly vitamin C, vitamin D, and zinc.* But other nutrients also play an important role in supporting immune health. Let’s look at five of them that might not be readily apparent to you.

1. Protein

Although vitamin C and zinc might be what you think of first, it’s certain that protein, with its varied amino acid component, is among the most important nutrients for healthy immune function.* Protein, and specifically the amino acids that are protein’s building blocks, is needed to make antibodies.

So if you don’t have adequate protein, then it can be difficult to mount a healthy immune response.* Amino acids are also essential to the production and activation of many immune cells, including lymphocytes, natural killer (NK) cells, and macrophages.*1 Some specific amino acids, like arginine, glutamine, and cysteine, are needed in higher amounts for wound healing and in times when your immune system is stressed.*2

2. Iron

Many individuals think iron isn’t good for immune health because they have heard the body naturally sequesters iron (takes iron out of circulation) during an active infection. Although this is true, the whole story is much more complex. If you don’t have adequate iron, then your body can’t make important immune cells, such as T lymphocytes.*3 Other immune cells, like neutrophils, require iron to function normally.* So if your iron level is too low, then your immune system might not work as well when you need it. 

3. Copper

An essential trace mineral, copper often gets lost in the shadow of iron and zinc – the latter a mineral it needs to stay in balance with. If your copper level is inadequate, then your body can’t make an adequate number of the important immune cell, the neutrophil, which is one of the first cell types to respond to an infection.4

Copper also plays a central role in the body’s production of superoxide dismutase, an antioxidant enzyme that is most active in red blood cells and in the lungs. And although your body needs a normal level of copper to help guard against the accumulation of toxic heavy metals,* it is important that copper stay in a proper balance with other minerals because too much copper can be as detrimental as too little. 

4. Vitamin B6

also called pyridoxal 5'-phosphate – is a part of the B vitamin complex, and is best known for its role in energy production and supporting brain health.* It has also long been known that vitamin B6 is important for many aspects of normal immune health.* If its level is low, then some immune cells might not mature properly and antibody production can be impaired.*5 Research indicates this is a greater risk as we age or in certain health conditions like rheumatoid arthritis. 

5. Melatonin

When you think of melatonin, you probably think about sleep. Although technically a hormone, and not a nutrient, melatonin also has a powerful influence on immune function* – which helps explain why getting good sleep is so important for your health. Melatonin serves so many functions in immune health that it’s hard to list them all. It’s important for producing immune cells – macrophages and NK cells.*

It increases the production of specific interleukins (chemical messengers made by some immune cells that moderate immune response) – but it also decreases the production of other interleukins that contribute to overall immune balance.*6 Melatonin also generally supports innate immunity7 – our first line of defense against any kind of infection we encounter.* Although you can supplement melatonin, getting restful sleep is the most important thing for maintaining a normal level. If you aren’t sleeping well, then you might want to take a quiz or home health test to learn why and to find solutions for better sleep. You can also start with some basic sleep strategies that can be helpful to do at home. 


  1. Li P, Yin Y-L, Li D, et al. Amino acids and immune function. Br J Nutr 2007;98(2):237-252. doi:10.1017/S000711450769936X
  2. Grimm H, Kraus A. Immunonutrition – supplementary amino acids and fatty acids ameliorate immune deficiency in critically ill patients. Langenbecks Arch Surg 2001;386(5):369-376. doi:10.1007/s004230100241
  3. Ward R, Crichton R, Taylor D, et al. Iron and the immune system. J Neural Transm Vienna Austria 1996 2010;118:315-328. doi:10.1007/s00702-010-0479-3
  4. Percival S. Copper and immunity. Am J Clin Nutr 1998;67(5):1064S-1068S. doi:10.1093/ajcn/67.5.1064S
  5. Rail L, Meydani S. Vitamin B6 and immune competence. Nutr Rev 1993;51(8):217-225. doi:10.1111/j.1753-4887.1993.tb03109.x
  6. Carrillo-Vico A, Lardone P, Álvarez-Sánchez N, et al. Melatonin: buffering the immune system. Int J Mol Sci 2013;14(4):8638-8683. doi:10.3390/ijms14048638
  7. Calvo J, González‐Yanes C, Maldonado M. The role of melatonin in the cells of the innate immunity: a review. J Pineal Res 2013;55(2):103-120. doi:10.1111/jpi.12075