During winter, cold and flu risk can linger for months. As humans, we share our environment with a host of microorganisms - bacterial, viral, parasitic - that are foreign to us. The body does its best to deal with these invaders with a complex process that relies on a number of factors. In addition to known immune boosters, such as getting enough physical activity and eating a healthy diet, there are a few supplements on the shelves that may help boost immunity.
Foods that may help fight cold and flu:
Fruits and vegetables - Fruit and vegetable consumption boosts your circulating levels of all the cold- and flu-fighting nutrients you’re trying to get in pills like vitamin C, zinc and selenium.
Garlic- Garlic belongs in the allium family. Any member of this family, including onions and leeks, can help build up your immunity to ailments most common during fall and winter.
Whole grains- hole grain consumption (think intact grains like buckwheat, brown rice and oats) helps healthy gut bacteria flourish. This process can help tune up your immune system.
Quit smoking- If you are a smoker, a habit that severely reduces the body's ability to fight flu and colds, you should quit. To help you along, you can use a healthy dose of fish oil every day as well. One study found doing so could reduce cravings for nicotine and the amount of cigarettes smoked daily. You can get your daily dose of omega-3s in your diet as well as plant-based versions like hemp seed and walnuts.
Supplements to consider:
Vitamin D: Even if you consumed the “perfect” diet, it would be very difficult to get enough vitamin D because very few foods provide enough of it. The best source of vitamin D comes from the sun’s UV rays absorbed through the skin. Since many of us live in areas where UV rays are weak, or we just don’t want to be exposed to the sun, a supplemental option is the next best thing. A 2017 study in the British Medical Journal found supplementation could protect against colds and flu. Though two earlier studies found vitamin D did not prevent colds, most recent analysis dissected the raw data of past studies and showed daily or weekly supplementation in people with low levels benefited the most.
Foods that have more vitamin C than an orange:
Zinc- A 2016 study found zinc supplementation in elderly adults helped boost zinc levels and immunity. Though you can get zinc from foods like sesame and pumpkin seeds, lentils and turkey, the elderly population studied was more prone to not getting adequate amounts in their diet, making them more susceptible to infection. Further studies have demonstrated zinc can decrease the duration of the common cold.
Probiotics - When it comes to building up defenses against the cold and flu, start by building the army in your gut. One study found college students who took probiotics in a supplement form had reduced duration and severity of the common cold. Further, a 2017 animal study found a specific gut microbe, triggered by the consumption of flavonoids found in tea, berries, and chocolate could help reduce the incidence of flu.
Vitamin C- Many studies have linked the consumption of larger doses of vitamin C to a reduction of the common cold and an increased ability to fight infection. Keep in mind, however, that consuming mega doses of vitamin C can cause diarrhea and gastric distress. So while it’s most likely safe to take the tablets and powdery packets this winter, try not to have them all day long. The upper tolerable limit for adults is 2000 mg.
In addition to dietary factors, maintaining a healthy weight, managing stress, getting adequate sleep, regular physical activity and good hand washing practices are critically important factors in fighting against cold and flu.
