Making your own smoothie is a sure way to get immune-strengthening nutrients, especially when you make them with fresh ingredients. On the other hand, the content of commercially prepared smoothie mixes may vary more than you may realize, with some being nearly void of nutrients. Check the labels because some smoothie mixes do contain vitamins that boost the immune system, such as vitamins A and C. Beware of added sugar in smoothie mixes though, as excess sugar can depress the immune system.
Nutrients in Immune System
The immune system is a network of specialized cells and organs that must communicate with one another and coordinate attacks against invading pathogens. This extensive system depends on a constant supply of nutrients.
If your diet falls short of these nutrients, the immune system is suppressed and you become more susceptible to infections and illnesses, according to a report in the Annals of Nutrition and Metabolism in August 2007.
In addition to protein and essential fatty acids, the Linus Pauling Institute lists 11 vitamins and minerals needed to keep the immune system working up to par. Several of the vitamins -- vitamins C, D, A, B-6 and folate -- are provided by some smoothie mixes, or you can easily add them by using fruits, milk, yogurt and greens.
Vitamin C Stimulates Immune Cells
Vitamin C supports the immune system as an antioxidant, but it also has a more direct role. It stimulates the production of white blood cells that attack bacteria and it also increases levels of antibodies, which identify and destroy foreign pathogens.
In laboratory mice, vitamin C participates in the immune response that helps kill the influenza virus, according to a study in Immune Network in April 2013.
Vitamin C is one of the more common nutrients found in smoothie mixes. Make your smoothie with berries, oranges, kiwi, guava and papaya to get the most vitamin C.
Vitamins A and D Strengthen the System
Your skin and respiratory tract are the first line of defense because they block bacteria from getting inside your body. Healthy skin and mucosal cells depend on vitamin A. Vitamin A also ensures the immune system’s natural killer cells work properly.
People with low levels of vitamin D are at a higher risk for developing infections, notes an August 2012 study in the Journal of Investigative Medicine. Vitamin D helps regulate the growth of immune system cells, including proteins that directly kill bacteria.
The best way to get both vitamins is by blending your smoothie mix with fortified low-fat milk or yogurt. Fruits such as apricots, peaches and mangoes are also good choices for vitamin A. If you like green smoothies, leafy greens also provide vitamin A.
B Vitamins Produce Proteins
Folate and vitamin B-6 both help produce proteins with vital roles in the immune system, such as antibodies and proteins that carry signals between immune system cells. A study published in the April 2010 issue of the Journal of Proteome Research reported that low folate is associated with lower levels of proteins that regulate immune activity.
You may not find many commercial smoothie mixes that contain much folate or vitamin B-6, but you can take care of that by using folate-rich oranges and tropical fruits, as well as bananas for vitamin B-6. If you want to go a little more savory, avocados and spinach are both good sources of folate and vitamin B-6.
Add Probiotics to the Mix
Probiotics are beneficial bacteria that can improve your immune system and overall health when consumed in adequate amounts. After probiotics reach the large intestine, they help stimulate the production of antibodies and other types of cells that ensure a strong immune system. Probiotic cultures also keep the wall of the gut healthy, which is important because it forms the barrier that stops unwanted substances from crossing into your bloodstream.
For optimal immune support, consume probiotics regularly, recommends the Linus Pauling Institute. Probiotics are found in yogurt with live cultures and milk kefir. Some smoothie mixes are made with these ingredients, but it is also easy to add them to your smoothie as their flavors work well with smoothie mixes.