What Is Vitamin C's Role In Immune Function?
Vitamin C is an essential nutrient. It is used by the body in various ways and can be consumed through many foods, namely fruits and vegetables. When people don’t get enough vitamin C-rich foods in their diet, they can also use supplements to increase their vitamin C intake. However, eating vitamin C through food is always the better way because it’s more bioavailable. Bioavailability refers to how much of a nutrient the body absorbs.
When it comes to vitamin C and health overall, people who lack adequate amounts can deal with various issues. For example, people who are severely deficient in vitamin C can develop a severe disease known as scurvy. In more moderate cases, a deficiency can cause skin and hair health issues, easy bruising and slow-healing wounds, joint pain and weak bones, and poor immunity.
Let’s take a deeper dive into vitamin C and immunity – because vitamin C’s role in immune function is more important than you may think.
What is vitamin C?
Vitamin C is a form of a water-soluble vitamin. That means it is absorbed into the body through water. That also means it is typically flushed out of the body with water; thus, adequate vitamin C levels must be restored daily through food or supplementation.
What does the body use vitamin C for?
The body uses this important nutrient for various things. It plays a role in tissue repair, collagen formation, and the production of neurotransmitters, which are molecular messengers in the brain that help receive signals. Vitamin C also acts as an antioxidant to protect against free radical buildup and damage.
Free radicals are molecules that can cause damage to cells and other areas of the body if antioxidants do not adequately balance them. Free radicals can take over and cause oxidative stress without proper vitamin C intake. Oxidative stress encourages widespread inflammation, tissue damage, and other issues leading to chronic diseases such as heart disease and cancer.
Vitamin C also helps the body regulate hormones. When hormones become imbalanced, it can lead to various diseases, such as an over- or underactive thyroid or PCOS. Epigenetic regulation, a form of gene regulation that exists outside of typical genetic changes, is also highly reliant on vitamin C stores in the body.
Skin health also relies heavily on vitamin C. The skin barrier, a protective layer that acts as part of the immune system, needs vitamin C to stay strong and protect against infection and pathogens.
How does vitamin C support the immune system?
As mentioned above, vitamin C’s role in the immune system is vast. It actually starts with the skin. Many people don’t automatically think of skin health when they think of immunity. However, the skin barrier is the largest and first defense used by the immune system to keep out pathogens and other threats.
By helping with the skin barrier, vitamin C:
- Enhances collagen levels to keep the skin solid and stable
- Protects against damage
- Enhances the differentiation of specific skin cells known as keratinocytes
- Ensures that wounds heal in an appropriate amount of time
Immune cells also require vitamin C to keep themselves ready to battle against pathogens or other things that threaten your health. The vitamin encourages the proper action of immune cells, known as neutrophils and macrophages. Neutrophils are white blood cells that help the innate immune system, which is the one you are born with, alert the rest of the immune system to a threat. These cells are non-specific, meaning they don’t remember specific viral or bacterial invasions but rather sense that something is off and begin to sound the alarms.
Macrophages are cells that specialize in the detection and destruction of pathogens. They identify harmful organisms within the body and then help activate other immune cells so that they’re ready to kill whatever is harming the body.
More specialized immune cells known as B- and T-cells are also affected by vitamin C. B cells take the threat and neutralize it by creating antibodies. Antibodies need to be produced by these cells in the right amounts to bind to harmful pathogens and clear them out of the body. T-cells are specialized cells that remember specific viruses or bacteria or any other dangerous substance so that if it ends up in the body again, they are ready to fight it off.
Lastly, vitamin C helps to modulate the production of proteins that work for the immune system but can sometimes become overactive, known as cytokines. These proteins encourage inflammation in the body, and when they act as they should, only appropriate inflammation occurs. With enough vitamin C, they can do their job.
How much vitamin C do I need for immune support?
Vitamin C levels may vary slightly depending on the person. However, there is typically a daily recommended amount for children and adults. Children need anywhere between 15–75 mg of vitamin C per day. Adult women need slightly less than men at 75 mg a day. If breastfeeding or pregnant, however, they should get at least 85–120 mg daily. Men require roughly 90 mg of vitamin C daily to reach their recommended daily intake (RDI).
You can take more than your RDI daily, but you don’t have to in order to keep your immune system running at its best. Getting the proper amount will do wonders for your immune health.