Written by Chisa Nagai, Grant Writing & Development Intern

With flu season, and the common cold that thrives during the winter season, it’s important to be aware of the produce you consume in order to maximize the health benefits of your diet. Some examples of the key micronutrients that boost the human immune system include vitamin A, vitamin B6, vitamin C, and zinc. By eating a diet that consists of a wide variety of locally sourced seasonal produce, you can consume the micronutrients your body needs in a tasty and sustainable way, while also boosting your immune system.

Vitamin A is known to enhance immune response through its regulatory roles in several immune processes. It has anti-inflammatory properties, which play an essential role in the immune response in and of itself. Vitamin A also promotes the production of antibodies, which is essential in antiviral processes. A few examples of winter produce that contain high levels of vitamin A are carrots and broccoli. These vegetables are also rich in other vitamins and minerals such as vitamin C and potassium, so they can be incorporated into your everyday diet.

Vitamin B6 is a part of the B vitamins class and can boost your immune system by supporting a wide range of biochemical reactions in the immune system. Vitamin B6 also regulates immune responses through its anti-inflammatory and antioxidant properties. Bananas and sweet potatoes are both winter vegetables that are high in vitamin B6. To maximize the benefits of vitamin B6 as well as other nutrients, sweet potatoes should be consumed with the skin.

Vitamin C is well known for being an immune booster and an all-around essential vitamin, due to its antioxidant properties and ability to heal wounds. More specifically, vitamin C contributes to the immune system by aiding in a variety of cellular functions, while also enhancing microbial killing through its accumulation in phagocytic cells that play a major role in the immune system. Most winter produce contains vitamin C, but a few examples that are especially rich in vitamin C include oranges, lemons, swiss chard, and broccoli. Since vitamin C can be found in most citrus fruits and leafy green vegetables, it is easy to incorporate it into your everyday diet.

Last but not least, zinc is an essential micronutrient that can boost your immune system by supporting the growth and functions of immune cells. Although only a small amount of zinc is needed for humans, even a mild deficiency can alter the immune system by slowing down the activity of important immune cells that protect the body from viruses and bacteria. Some examples of winter produce that are good sources of zinc include avocados and mushrooms. Nuts and seeds are also good sources of zinc, and with the winter season in mind, pumpkin seeds provide a healthy and sustainable way to consume the necessary amount of zinc.

Eating a varied, colorful, and seasonal diet filled with essential micronutrients can help keep your immune system strong throughout this winter season. A balanced diet that provides you with the nutrients you need is also important for your overall well-being while consuming locally sourced food. However, it’s important to remember that the best way to keep you and your loved ones safe and healthy is to follow your local public health department’s guidelines.


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