As we approach mid-fall and winter months, cold and flu season is upon us. With the average adult getting 2-4 colds per year and average child between 5 and 10, we are no strangers to the uncomfortable symptoms that colds bring upon us. While you may be familiar with hygienic practices to prevent colds such as; washing your hands and not touching your nose, eyes, mouth, ears with your hands while in public, there are also numerous nutrition practices that can help prevent colds.
Eat The Rainbow
As cliché as this saying is, it really does offer some good advice. For those of you that have not heard the saying 'Eat the Rainbow,' it applies to eating a variety of fruits and vegetables of all different colors throughout the day. A 2003 study found that there was a synergistic effect of consuming different fruits and vegetables together.(1) Meaning, where some F+V lack in nutrients others make up, contributing to good overall nutrition status. While taking a multivitamin can provide many of the same nutrients, they do not provide the phytochemicals, fiber and other plant compounds necessary to boost immunity. Try to eat a variety of F+V daily to achieve a good nutritional foundation, this can then be built upon to further increase immunity.
Probiotics and Prebiotics
Over the past few years in particular, interest in probiotics has skyrocketed. Interest has also increased in the science community resulting in numerous studies on probiotics, some taking immune function into consideration. So what are probiotics? Probiotics are cultures of live beneficial bacteria that can serve a function in the body. Probiotics are contained in fermented and cultured foods like yogurt, kefir and kimchi. They have several roles in the body but the role they play in immunity in particular is to improve the immunological barrier in the intestine.(2) This means, when you are exposed to a harmful pathogen that makes its way through your digestive system, probiotics may help prevent that pathogen from entering your blood stream. This in turn prevents the pathogen from spreading throughout your body and infecting you. While this is a very simplistic view, it gives you the general idea of how probiotics benefit your immunity.
You may also have heard of the term 'prebiotics.' Prebiotics are essentially what probiotics feed off of. Prebiotics are contained in fiber-rich foods such as onions, asparagus, leeks, wheat bran, whole wheat products and bananas to name a few. Prebiotics and probiotics go hand in hand and when included in your diet can help improve your immunity among many other markers of health.
Vitamin C is a much debated nutrient in terms of its immune-enhancing effects. There have been studies that show it has slight immune benefits, while others have not found any effect. (3,4) The recommended daily intake for vitamin C is 75mg for women and 90mg for men. This amount can easily be obtained through the diet. Studies have shown that supplemental vitamin C does not have a significant effect (<10%) on the cure or prevention of the common cold in the general population. In athletes, the cold-preventative effect is more prominent at up to 50%.(5) For an athlete who frequently gets colds it may be worth supplementing with vitamin C in doses up to 2,000 mg per day. (6)
According to a vitaminretailer.com survey (7), fish oil is the number one dietary supplement in the US, followed by multivitamins. The scientifically proven benefits of fish oil range from healthy heart function to reduced inflammation, but what about immunity? The cells in our body that are responsible for immunity are made largely of fatty acids, like those contained in fish oil. Consuming fish oil can help supply the immune cells in our bodies with the building blocks that they need to function optimally. Omega 3's can be obtained in the diet from foods like fatty fish (salmon, mackerel), flax seeds, hemp seeds, and egg yolks, among others. Most Americans do not consume enough omega 3's in their diets so it may be beneficial to supplement with fish oil. The recommended dose for general health is 1000-3000 mg's or 1-3, 1000mg soft gels.
Some minerals such as Iron and Zinc are important factors for the immune system. Deficiencies in either of these minerals can result in increased infection. While supplements can provide these minerals it's best to get them from your diet. Some high iron and zinc containing foods are beef, oysters, beans, and leafy vegetables (think spinach and kale) to name a few.
The Take Home Points
- Eat a variety of fruits and vegetables to take advantage of synergistic effect of nutrients
- Consume fermented or cultured foods, like yogurt or kimchi, on a regular basis
- If you don't enjoy fermented or cultured foods consider taking a probiotic supplement
- Ensure to include high fiber (prebiotic) foods in your diet such as fruits, vegetable and whole grains
- Boost your vitamin C intake with added high Vit-C fruits and veggies like broccoli and citrus
- Consider supplementing with vitamin C if you exercise intensely on a regular basis
- Get in your omega 3's, this can be met by getting at least 2 servings of fatty fish per week
- You may want to supplement with fish oil if you don't regularly consume fish or high omega 3 foods (listed above)
- Load up on minerals, especially iron and zinc, from sources such as leafy vegetables, beans and red meat.
Until next time my friends, BE ELITE!
- Venzon, Dawna, and Samantha Izzy. "Fruit, Vegetables, and Phytochemicals in Human Health and Disease." Phytochemicals (2012): 1-20. Web.
- Isolauri, Erika, Yelda Sutas, Pasi Kankaanpää, Heikki Arvilommi, and Seppo Salminen. "Probiotics: Effects on Immunity." American Journal of Clinical Nutrition 73.2 (2001): n. pag. Web.
- Semba, R. D. "Vitamin A, Infection and Immune Function." Nutrition and Immune Function (n.d.): 151-69. Web.
- Wintergerst, Eva S., Silvia Maggini, and Dietrich H. Hornig. "Immune-Enhancing Role of Vitamin C and Zinc and Effect on Clinical Conditions." Annals of Nutrition and Metabolism Ann Nutr Metab 50.2 (2006): 85-94. Web.
- The Cochrane Collaboration [online] http://www.cochrane.org/cochrane-reviews Chalker E, Hemila H, “Vitamin C for preventing and treating the common cold (Review)” The Cochrane Library. 2013.