Winter is known as cold and flu season.
Truth is, there is no such thing as cold and flu season. 
There is however, a period of 4-6 months during which the average immune system becomes weaker and more susceptible to illness as the days get shorter and colder and we spend more time indoors - and in closer proximity to other people and their germs.
Since it’s that time of year again, we put together this immune boosting guide to help you stay healthy and at your peak in every season.
1. Get Outside
People with the lowest levels of Vitamin D (25-Hydroxyvitamin D) were 40% more likely to develop 
These were the findings of a 2009 collaboration between the University of Colorado Denver (CU Denver) School of Medicine, Massachusetts General Hospital (MGH) and Children’s Hospital in Boston tested the Vitamin D levels of 19,000 people.
The best source of Vitamin D is the sunshine. The second best source is Natural Stacks Vitamin D3 in Coconut Oil.
The darker our skin, the more sun exposure we require to synthesize adequate levels of Vitamin D. The farther we are from the equator, the less intense the sun's rays - again increasing the amount of sun exposure we require for adequate Vitamin D.
It's easy to see now that decreased sun exposure in the winter months - due to shorter days and colder temperatures - is a major factor in setting boundaries for "cold and flu season".
2. Play In The Dirt
Spending time in nature boosts mood and immunity.
One theory from a meta-review of nature studies is that it relaxes our fight or flight response, helping us enter the parasympathetic state so we can recover and recharge. The studies in this review showed nature has a positive impact on numerous ailments, including: depression, diabetes, obesity, ADHD, cardiovascular disease, and even cancer. 
There's also research showing that interaction with the natural bacteria present in soil (nature’s biome) can enhance our own biome and boost our immune system. 
3. Cold Showers
Remember when your Mom said "Wear a jacket or you'll catch a cold!"?
Turns out Mom was wrong.
Most health experts agree that the reason winter is "cold and flu season" is not that people are cold, but that they spend more time indoors, in closer contact with other people who can pass on their germs. 
In fact, research suggests that cold exposure can boost immunity by increasing “antioxidative defense” as measured by several blood markers. 
Taking cold showers or sitting in an ice bath produces an adaptive response (the hormetic response) by exposing your body to a slight stressor. Your body comes back stronger from these micro-exposures to stressors.
We've talked about cold thermogenesis in greater detail HERE.
Our immune system relies heavily on a few crucial vitamins and minerals to keep us healthy.
Vitamin C is a neuroprotective, antioxidant powerhouse that has been shown numerous times to bolster the immune system.
Zinc has also been show to reduce the severity and the length of colds [7,8,9]
That's why we combined them in our Vitamin C + Zinc formula.
5. Load Up On Bone Broth
Chicken soup - made the way it was in traditional times - really can boost immunity.
This requires the soup to be made with bones or chicken feet to provide the collagen that can enhance our immune system.
Collagen is a special type of protein that was found in great quantities in our ancestors diets, but is largely missing from modern diets. Found in bones, cartilaginous materials and [10,11]
If you want to make your own bone broth, we have your Ultimate Guide with Kettle & Fire's co-founder Justin Mares right here.
6. Herbs, Spices and Homeopathic Foods
Garlic, ginger, onions, and other homeopathic plants can boost our immunity. The Cleveland Clinic published this list of foods to add to your menu for a healthy immune system.
We can also boost our immune system while we enhance the flavor of our favorite foods with herbs and spices. We covered 5 health promoting herbs in this blog post.
7. Pump Your Lymph System
The lymphatic system is a series of vessels, nodes and organs that drains excess fluids and proteins from tissues all around the body so it can remove waste products produced by cells and fight infections.
It also absorbs fats and fat-soluble vitamins from the digestive system and transports these into the bloodstream.
Since it job is to collect and filter out waste products, we can benefit from improving it's circulation and helping it drain those unwanted substances.
Lymph system circulation and drainage has been shown to [source]
We can assist in this circulation and draining by inversion, jumping rope, using trampolines, or by performing handstands & handstand pushups (HSPU) as a form of inversion.
8. Eat Fermented Vegetables Daily
Fermented vegetables like kimchi, Natto, and sauerkraut contain live cultures that improve the health of our digestive system.
It turns out, they also have cancer-fighting compounds that can boost our immune system.
In a 1999 study funded by the NIH, researchers analyzed cabbage before and after fermentation and found the glucosinolates in cabbage dissolved into a class of enzymes that have been shown in prior studies to prevent cancer.
Further, when consumption of fermented vegetables went from "low to high", cancer rates decreased as much as 40%. 
9. Have More Sex
Stimulating the reward system of the brain increases immunity. 
Scientists activated neurons in a part of the mouse brain that processes rewarding activities such as eating and sex. The next day, the mice were injected with E. Coli and they showed increases in both short-term and long-term immune responses to the pathogen, compared with mice in a control group.
Maybe this has been Keith Richards's longevity secret all along...
Mushrooms contain a special polysaccharide known as beta-glucans that act as immunomodulators. These special compounds make mushrooms a powerful adaptogen that we can add to our arsenal to fortify our immune systems.
Each species of mushroom offers it own unique benefit, but Reishi, Turkey Tail, and Chaga have been used in longevity and immortality tonics by the Chinese and Russians for centuries. Modern medicine supports this traditional use with research supporting mushroom's ability to bolster our immune response. You can see numerous studies and read more about their benefits here.
Or get our ultimate Immune Supporting Stack HERE: MycoIMMUNE + Vitamin D3 + Curcumin. Use Code SAVE20 to save 20% on your first order.
- Harvard Health. The Reason For The Season: Why Flu Strikes in Winter. December 1, 2014.
- Ginde, A. MD. Association Between Serum 25-Hydroxyvitamin D Level and Upper Respiratory Tract Infection in the Third National Health and Nutrition Examination Survey Adit. Available online: http://www.ucdenver.edu/about/newsroom/newsreleases/Documents/VitaminDStudies/Ginde_ArchIM_2009%20(vitD%20and%20URTI).pdf
- Ming. Kuo. How might contact with nature promote human health? Promising mechanisms and a possible central pathway. Front. Psychol., 25 August 2015
- The Human Microbiome. AOBiome.com
- Harvard Health. How To Boost Your Immune System. September 2014.
- Siems WG. Improved antioxidative protection in winter swimmers. QJM. 1999 Apr;92(4):193-8.
- Maggini S. A combination of high-dose vitamin C plus zinc for the common cold. J Int Med Res. 2012;40(1):28-42.
- Carol S Johnston. Marginal vitamin C status is associated with reduced fat oxidation during submaximal exercise in young adults. Nutrition & Metabolism 20063:35. DOI: 10.1186/1743-7075-3-35
- Singh M. Zinc for the common cold. Cochrane Database Syst Rev. 2011 Feb 16;(2):CD001364. doi: 10.1002/14651858.CD001364.pub3.
- Guo S, DiPietro LA. Factors Affecting Wound Healing. Journal of Dental Research. 2010;89(3):219-229. doi:10.1177/0022034509359125.
- (2016). Structural basis for collagen recognition by the immune receptor OSCAR.Blood, 127(5), 529-537.
- Ju, Y H; Carlson, K E; Sun, J et al. (2000) Estrogenic effects of extracts from cabbage, fermented cabbage, and acidified brussels sprouts on growth and gene expression of estrogen-dependent human breast cancer (MCF-7) cells. J Agric Food Chem 48:4628-34
- Shai Shen-Orr, Asya Rolls, et al. NEUROIMMUNOLOGY. Reward system boosts immunity. Nature. 535, 10. (07 July 2016)