With the arrival of autumn come cooler temperatures, and maybe higher stress levels with the return to school and work routines. All these result in a more vulnerable phase and higher chances of infection.

From a traditional Chinese medicine (TCM) perspective, autumn is represented by the metal element and includes the lungs and large intestines. Both organs are in direct contact with the outside world, taking in air and food, and letting go of what we don’t need. For this reason, they are heavily protected by our immune systems. In fact, about 70–80% of our immune system is in our digestive tract. In TCM, the large intestine is about “letting go,” the obvious passing of stool, but there is also an emotional component to this. The lungs are associated with sadness as well as opening to new ideas and clear thinking.

There are many things we can do to nourish our beings and keep our immune systems in top shape. Here are some ideas and reminders for the autumn.

Slow Down

Take self-time to reflect and adjust to the faster pace and higher intensity that September might bring. Autumn tends to be a time of introspection and a quieter time for planning. Ideas include breathing exercises, guided imagery, mindfulness, walking, spending time in nature, journaling, or sitting with a warm cup of tea. Many of these activities support the lungs and also help to calm the nervous system and discourage stress.

Eat Warming Foods

As temperatures decrease, it is important to eat warming foods and herbs to support digestive function. These include warm cooked meals rather than lots of raw summer salads. Warming spices include ginger, cinnamon, nutmeg, cloves, and pepper that can be added to soups, stews, roasted vegetables, or an apple crumble. Eating seasonally is ideal, especially all that comes during the autumn harvest. Garlic; onions; mushrooms; squashes; pumpkins; root vegetables such as carrots, potatoes, yams, parsnips, and turnips; and apples and pears as our autumn fruit: All these provide warmth to the body, move digestion, and help clear pathogens.

Vital Vitamins and Minerals

Vitamin C is an all-time favourite immune support. A deficiency in this vitamin is related to an impaired immune response and higher risk of infection. Vitamin C has various effects on both the innate and adaptive immune systems. A key role is that vitamin C protects barrier function so that pathogens cannot enter. It can also increase the amount of B and T cells, supporting immune activity.[1] Vitamin C acts as an antioxidant and supports phagocytes that not only engulf pathogens, but also clean up and resolve inflammation.[2]

Vitamin D, our sunshine vitamin, is well known to promote a healthy immune response. It has been shown to have a positive effect on many autoimmune conditions.[3]^,[4] Many people are deficient in vitamin D, especially in Canada, hence the need for supplementation. Factors include a high use of sunscreen as well as less outdoor time and, unfortunately, our northern location doesn’t help. I often recommend patients increase their supplementation from September to April, and to get levels tested if taking high doses for long periods of time.

Zinc has numerous effects on the immune system as well. First off, it protects the skin and epithelial cells from pathogens entering. The function of immune cells and their normal development in the thymus and bone marrow is very dependent on zinc. Macrophages, key white blood cells that eat up pathogens and send signals for other immune cells to come, cannot do their job without zinc. Natural killer cells, neutrophils, and B and T lymphocytes also use zinc for proper functioning.[5] Bottom line: When zinc is deficient, immune activity is impaired.

Boost with Botanicals

Astragalus is a Chinese root used to strengthen the immune system and tonify the lungs. It is also helpful as an “adaptogen” to protect against the negative effects of stress. Astragaloside IV is a notable compound extracted from this root, which regulates the immune system, protects cell membranes, and is an antioxidant and anti-inflammatory.[6] Astragalus can be taken in capsules, liquid tinctures, or by boiling the root. A nice autumn recipe with astragalus is change-of-season tea (see recipe section).

Andrographis also has immune-modulating ability and is commonly used to ward off colds, flus, and other typical bacterial and viral infections. In a study on healthy people, andrographis was shown to increase lymphocytes and modify cytokine production, all benefiting immune function.[7]

Codonopsis, another Chinese root known to have immune benefits, is used to tonify lung qi and warm the body in TCM. That sounds perfect for autumn support.

Fight Off with Fungi

Mushrooms are superfoods used primarily for immune modulation. β‑Glucans are polysaccharides from mushrooms with immune-enhancing abilities that have been substantially researched. Hot-water extraction is the best way to access these β‑glucans, so eating mushrooms in cooking is an easy at-home immune support. Other medicinal mushrooms, such as reishi, chaga, or turkey tail, can be found dried or in powders to simmer in hot liquids, and of course change-of-season soup. They all come in capsules as well, as nutraceuticals with therapeutic potential.

Bacterial Barrier

Knowing that a huge part of our immune system is in the gut, adding probiotics is a no-brainer. There has been a lot of research on specific strains of these friendly bacteria. Of note are Lactobacillus rhamnosus, L. helveticus, L. reuteri, L. casei, Bifido infantis, and B. bifidum, all helping immune function. The overall finding is that they work better together. Colds, flus, wheezing, asthma, intestinal infections, and allergies have all seen benefit with probiotic mixtures.[8]^,[9] Look for a multistrain supplement and keep them in the fridge. Equally important is to buy enteric-coated capsules so they can arrive alive in your intestine where they deliver their magic!

Dr. Krista Mackay, BSc, ND

Krista practices both in Montreal, Quebec, and Montevideo, Uruguay. A busy mom of two boys, she focuses on naturopathic general/family medicine, helping to find a reasonable balance to optimal wellbeing and stress management, including nutrition, herbal medicine, and mind-body work.

kristamackay.ca