Probiotics: the word seems to be just about everywhere, from the label of your morning cup of yogurt to the description on your trendy bottle of kombucha. Even if the word is familiar to you, however, how much do you actually know about probiotics, what they do for your body and where they can be found? It's easy to get caught up in the buzz--and there certainly is truth to the growing reputation of probiotics as a cornerstone of healthy living. However, before you switch to an all-yogurt diet or consider trying probiotic supplements, here's what you should know about these beneficial bugs.

What are probiotics?

Put simply, probiotics are strains of beneficial microorganisms that can help augment the existing good bacteria in your digestive tract. To put this in context, your digestive tract has trillions of different microorganisms, often referred to as your gut microbiome. Indeed, as hard as it may be to believe, the bacterial population of your gut is greater in number than all of the cells in your body. Probiotics can come from a variety of sources, from yogurt to daily supplements.

Whatever the source, however, the goal of taking probiotics is to bring balance to your gut microbiome by supplementing the naturally-occurring good bacteria in your digestive tract; in turn, a balanced gut microbiome can positively affect many other areas of your body, from your skin to your metabolism.

Why is good bacteria so important?

In a world awash with anti-bacterial soaps and antibiotics, it's easy to forget that not all strains of bacteria are bad. In fact, many bacterial strains are not just beneficial but downright essential for the health of your gut (and, by extension, the rest of your body).

Good bacteria play a key role in supporting your immune system, helping to prevent infections such as the common cold and to stimulate your immune system's response to a wide variety of triggers. Adequate populations of good bacteria in your gut also help promote a healthy digestive tract, reducing common digestive issues such as constipation, bloating and diarrhea.

Your metabolism, energy levels and weight are influenced by the presence of ample good bacteria, and the right balance of bacteria is tied to preventing yeast infections and promoting oral health; even your mental health and mood can be affected by the microbial balance in your gut.

Can you get adequate amounts of probiotics from the food you eat?

Probiotics naturally occur in a number of foods, particularly dairy products and fermented items. Yogurt is probably the most popular dietary source of probiotics, but certain cheeses, kefir, kimchi and sauerkraut all have probiotics. However, despite the broad reputation that yogurt and other foods have as excellent sources of probiotics, the truth is that your diet is unlikely to have the amount and variety of probiotic strains that your body needs to truly function its best.

Why is this the case? There are a variety of factors. To start, only a limited number of probiotic strains naturally occur in foods. The amount of good bacteria that many foods have is also rather low; while many studies tout the benefits of eating yogurt daily, they often fail to highlight the fact that you need several daily servings to reap the rewards. You may also be unwittingly choosing food options that actually have little to no probiotics at all. For example, despite their status as a probiotic superfood, studies have found that many widely-available yogurts have probiotic doses that are far too small to be effective.

In other words, to truly get the number and variety of probiotics that your body needs to work its best, you'll need to take a daily probiotic supplement.

How can a probiotic supplement benefit your body?

As previously noted, good bacteria play an important role in regulating many different processes in the body, and adding a probiotic supplement to your daily routine can ensure that your body reaps the wide-spread benefits of a balanced gut microbiome. So what exactly can a probiotic supplement do?

Given the effects that probiotics have on the bacterial balance in your digestive system, it's no surprise that they can have a significant positive impact on digestion. Research has found that regular probiotic use can help treat constipation as well as prevent diarrhea.

Another big benefit of probiotics is an improve immune system regulation. This effect is backed up by a wide body of research, such as one study that suggests that probiotics may inhibit the production of cortisol--which acts to suppress immune system function--in stressful situations. Likewise, probiotics have been shown to boost metabolism, lower the effects and incidence of metabolic disease, and promote healthy weight management.

Perhaps most surprisingly, probiotics can even affect your mood and mental health. For example, studies have found that probiotic supplements boost the production of key neurotransmitters such as serotonin that play a role in controlling depression and anxiety. Energy levels can also be improved with probiotics; researchers at Australia's University of Newcastle found that athletes given a probiotic supplement experienced less fatigue.

Indeed, the potential health benefits of probiotics are almost too numerous to list, with scientific studies supporting their effects from helping treat common allergies and lowering cholesterol levels to promoting better oral health and lowering the recurrence of yeast infections.

So while probiotics might be one of the buzziest topics in lifestyle magazines and health-oriented blogs, there are actual results to back up the good reputation that this supplement has gained--and many reasons to add probiotics to your own daily routine.


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