Dietary Gut Fiber May Help with Skin Allergies

Allergies are the sixth leading cause of chronic illness in the US, with some of the most common allergies being hay fever, food allergies, and skin allergies. A new study by researchers at Monash University has found that microbial fermentation of dietary fiber in the gut can protect the skin against allergic disease. The findings point to future, novel treatments that can prevent allergies or nip them in the bud.

Skin Allergies in the U.S.

Some of the most common skin allergies in the US include atopic dermatitis (which causes dry, red, itchy skin that can form fluid-filled bumps), hives (red bumps or welts that are also known as acute urticaria), and contact dermatitis (which includes rashes, blisters, itching, and burning). Currently, home sanitation for people with allergies is a multifaceted process that includes choosing hypoallergenic bedding and furniture fabric, choosing the right flooring, and using allergy-friendly products made with gentle materials. Reducing clutter and dust can also help soothe allergy symptoms. Unfortunately, people with issues such as contact dermatitis are often exposed to allergens outdoors—for instance, children at school who lean on desks or use chairs that have been cleaned with harsh cleaning products can develop rashes and other types of irritation.

The Wonder of the Gut-Skin Axis

Scientists have long known that the gut microbiome (the myriad of bacteria that live in the gut) shapes the immune system. However, its effect on the skin has only recently been discovered. In the Monash University study, scientists found that feeding mice a diet that was high in fermentable fiber led to fermentation and the subsequent production of short-chain fatty acids (SCFAs). These acids protected mice against atopic dermatitis. One of these SCFAs, butyrate, is particularly useful in helping to build a healthy skin barrier. It takes just minutes to reach the skin, where it begins a process that strengthens the structural components of skin. Because SCFAs can be administered topically and they are well tolerated, said the researchers, they open up a wide array of preventative strategies for everything from skin allergies to asthma.

What Foods Are High in Fermentable Fiber?

Fermentable fibers are those that healthful bacteria use as food to produce compounds like butyrate. The latter not only helps quell skin cancer, but also has cancer-protective effects in the colon. Examples of fermentable fiber include artichokes, legumes, onion, barley, and oats. To boost the health of your gut, ensure you consume the recommended amount of fiber. The Institute of Medicine recommends that women aged up to 50 should ingest 25 grams of fiber per day (compared to 21 grams for women over 50), and men up to 30 should consume 38 grams per day (compared to 30 grams for those aged over 50). These recommendations are based on preventing heart disease. The lowest amount of dietary fiber that can lower the risk of colorectal cancer, on the other hand, is about 30 grams per day or more.

A new study has shown that fermentable fibers can potentially help reduce or treat allergies. The study focused on the skin, finding that butyrate strengthened the skin barrier. Consuming fiber can help promote a well-functioning gut microbiome, helping to keep various diseases at bay.