Probiotics are live microorganisms that provide health benefits when consumed in adequate amounts. Often called “good” or “helpful” bacteria, they contribute to the balance of your body’s natural microbes, particularly in the digestive system. While many people associate probiotics with manufactured supplements, they are also naturally present in various foods and can be acquired through contact with our surroundings.
Probiotic-Rich Foods from Nature
Dairy products like yogurt and kefir are familiar sources of probiotics. For these foods to be effective, their labels must indicate “live and active cultures.” Yogurt is produced by fermenting milk with bacteria, primarily Lactobacillus species, which help break down lactose. Kefir, a fermented milk drink with a thinner consistency than yogurt, is made using kefir grains, which are a symbiotic culture of bacteria and yeasts, resulting in a more diverse microbial profile.
Beyond dairy, fermented vegetables are a significant source of natural probiotics. Sauerkraut, which is finely cut fermented cabbage, and kimchi, a traditional Korean side dish made from fermented vegetables like napa cabbage and Korean radish, are rich in lactic acid bacteria. True pickles, which are cucumbers fermented in a saltwater brine rather than a vinegar solution, also contain these beneficial microbes.
Fermented beverages have also become popular for their probiotic content. Kombucha, a fizzy, sweetened black or green tea, is fermented with a symbiotic culture of bacteria and yeast (SCOBY). Similarly, water kefir is a carbonated beverage made by fermenting sugar water with water kefir grains, offering a dairy-free alternative.
Environmental Exposure and Microbial Diversity
The food we eat is not the only natural source of microorganisms; our surrounding environment plays a substantial part in shaping our personal microbiome. Everyday activities can expose us to a wide array of microbes that differ from those found in fermented foods. This exposure contributes to a more varied and robust internal microbial community.
Direct contact with nature is a primary way to encounter these environmental microbes. Gardening, for instance, involves interaction with soil, which is a complex ecosystem teeming with soil-based organisms. Similarly, spending time in natural landscapes like forests and parks exposes our skin and respiratory systems to a different set of airborne and surface-dwelling microorganisms.
Interacting with animals also introduces us to a unique collection of microbes. Pet owners are regularly exposed to the specific microorganisms carried by their animals, which can influence the composition of the human microbiome.
Natural Sources Versus Probiotic Supplements
Foods like yogurt, kefir, and sauerkraut offer a broad diversity of bacterial strains. These foods also provide other nutritional components, such as fiber—which acts as a prebiotic, feeding the beneficial bacteria—and various vitamins and minerals. The potency and specific strains in these foods can be variable, however, depending on the fermentation process and storage conditions.
Probiotic supplements, on the other hand, provide specific, targeted strains of bacteria in high concentrations, often measured in colony-forming units (CFUs). This allows for a more controlled approach, which can be beneficial when addressing a particular health concern. The strains found in supplements, such as various species of Lactobacillus and Bifidobacterium, have been studied for their effects on specific conditions.
Ultimately, obtaining probiotics from whole foods and taking supplements are not mutually exclusive strategies. A diet rich in fermented foods provides a wide array of beneficial bacteria and nutrients that support a healthy gut environment. Supplements can then be used to introduce a high dose of specific strains that may not be available in food.