Microbial Misconceptions: Fermented Foods

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We’ve officially (finally) made it to the last few weeks of 2017, and that means that foodies and trend forecasters are busy compiling their lists of food trends to watch for in 2018. While new fads and flavors are cropping up all the time, fermented foods have been perennial favorites of chefs, food bloggers, health nuts, and even your grandparents (shoutout to my grandma’s homemade pickles). But as their popularity continues to grow, it’s easy to lose sight of the real vs. perceived health benefits of fermented foods, and that’s where we come in.

Fast Facts on Fermentation

Fermenting foods takes many forms, ranging from the creation of wine from grapes, making yogurt or kefir from milk, curing meats, or converting a regular old cabbage into kimchi or sauerkraut. But they all have one thing in common: they’re produced by the actions of microorganisms. Certain species of bacteria, yeasts, or molds are responsible for the changes in flavor, texture and appearance of fermented foods.

Fermented vs. Probiotic vs. “live and active cultures”: What’s the Difference?

Microbes are required to turn any food into its fermented version. Some foods, like freshly made kimchi and most fermented dairy products, may still contain live and active cultures (meaning that the bacteria are still alive and working their magic). However, by the time the final products like beer, wine, vinegars, sauerkraut, cured meats and sourdough bread reach store shelves, the bacteria have been killed or inactivated through processes like pasteurization, baking, or filtering. The microbes are now out of the “live and active cultures” game. Even if a food still proclaims the presence of live and active cultures, this is not the same as being probiotic. The World Health Organization classifies a probiotic as, “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host”. Bacteria classified as Bifidobacterium and Lactobacillus are among the most well-studied and generally well-accepted examples that meet the probiotic definition. They’re commonly found in dairy products, like yogurt and kefir. Fermented foods with live probiotic cultures may play a role in gut health and other conditions, but many foods with live and active cultures can’t make the same claim since they don’t contain strains with known health benefits.

How Do Fermented Foods Stack up Nutritionally?

Whether they’re raw, roasted, steamed or pickled, vegetables provide nutrients like vitamins, minerals and fiber. However, the nutrient content may vary depending on the way they’re prepared. Fermented dairy products are lower in lactose than fresh milk or ice cream, which means they’re usually better tolerated by people with lactose intolerance. On the other hand, some fermented foods may be higher in sodium than their raw counterparts or have added sugars. Reading nutrition labels can give you a sense of the types and amounts of nutrients you’re getting with each product.

Do Fermented Foods Make My Diet Healthier?

We don’t know if eating fermented foods affects the inevitable afternoon attraction to the vending machine, but there is emerging evidence that what we eat, the microbes living in our gut, and our brains are interconnected. The nerves in our digestive tract, also known as the enteric nervous system, communicate with the brain through neurotransmitters like dopamine and serotonin. It turns out that our gut microbes produce quite a lot of these neurotransmitters, which can affect our mood and may also play into food cravings and eating behaviors. What we eat affects the composition of the gut bacteria, and these bacteria can then communicate back to the brain. This system is known as the gut-brain axis. Some scientists have suggested that changing the microbes in our digestive tract could be a treatment for overeating or triggering cravings for certain foods, but it’s too early to start recommending specific dietary changes. Until we know more, eating mindfully, watching portion sizes, and enjoying a variety of foods are great approaches for maintaining a healthy eating pattern.

Judging from the popularity of pickle plates, kombucha and craft beer, it’s safe to say that fermentation will remain on-trend for 2018. We’ll continue to track new developments in the science behind their effects on health, and we can’t wait to enjoy more of these tart and tasty foods in the New Year!