As the temperatures start to drop, your likelihood of catching a cold start can increase. Thankfully, you can arm yourself early with three known immune boosters: beta glucan, colostrum, and good old vitamin C.

Beta glucan is a complex sugar derived from baker’s yeast, oats, barley, and some medicinal mushrooms. It helps to boost your

immune system by stimulating the white blood cells to in your immune system that swallow up any foreign material, including viruses, bacteria, and fungus.

Colostrum is an immune- and growth-enhancing pre-milk fluid produced by all mammals in the last few months of pregnancy and just after birth. It has been shown to help fight off common illnesses like colds, flu, allergies, and bronchitis. Plus, it contains numerous immunoglobulins, which help boost your immune system and provide protection against invading bacteria and viruses. Finally, colostrum is a good source of the probiotic acidophilus, which helps prevent gastrointestinal infections, including diarrhea.

Vitamin C is an old standby for boosting immunity. Like beta glucan, vitamin C helps to bolster white blood cell production and increases germ-fighting antibodies. It has been shown to be particularly helpful in treating and preventing lung-related conditions. According to a 1994 study in the International Journal of Vitamin and Nutrition Research, elderly patients with severe, acute bronchitis and/or pneumonia who took 200 mg of vitamin C a day had more relief from their symptoms than those who took a placebo.