6 Science-Backed Benefits of Probiotics & Who Should Take Them
The microbiome, the collection of bacteria living in the gut, plays an integral role in overall health. Two of the most popular ways to take care of your gut and give it the support it needs are probiotic supplements and probiotic-rich foods, like yogurt and kimchi. Here, we'll dive into what exactly probiotics can do for you, your gut, and your overall health.
What are probiotics?
Many people think about bacteria in terms of germs that make you sick. But probiotics are bacteria that help support good health, especially in the gut.* These friendly bugs are key for maintaining the microbiome.*
Where can you get them? Probiotic bacteria are found in fermented foods like yogurt, kefir, sauerkraut, kimchi, and tempeh. But you can also find them as supplements, including refrigerated capsules, shelf-stable pills, and powders.
6 Probiotic benefits.
When you take a probiotic supplement, you add more of these good bugs to your gut.* As Robert Rountree, M.D., renowned integrative physician, explains it, "The probiotics are like good cops. We're putting in the good cops, and the good cops can keep watch over the bad guys." Here's a closer look at how that can affect your health:
1. They're good for your gut.*
Probiotics might be best known for their impact on gut health.* "Think of probiotics as your little helpers that restore order and help maintain harmony in your gut ecosystem," says gut health expert Vincent Pedre, M.D. "They outnumber and antagonize unwelcome pathogens, including unfavorable bacteria, yeast, and parasites."
A large body of evidence has shown that probiotics are beneficial for managing gut issues like diarrhea caused by taking antibiotics, as well as constipation.* They can also play a valuable role in providing nutritional support for chronic and acute gastrointestinal disorders like irritable bowel issues and Clostridium difficile infections.*
2. They can help with weight management.*
These good bugs might play a positive role in weight maintenance too.* Gut bacteria play an important role in metabolism, involved in everything from digestion to energy production and storage and even appetite regulation.
Several studies have shown that the microbiomes of obese individuals are different from the microbiomes of lean individuals. Interestingly, when an obese person receives a fecal transplant of lean bacteria, they lose weight and body fat. And the reason might have to do with how microbes help us break down food.
"Certain bacteria are better at extracting energy from food than others," says Rountree. "It's that simple." So, if you happen to have more of these desirable bacterial strains in your gut, then you could eat the same food as a friend and you end up turning it into energy, while your friend turns it into fat.* One of life's most frustrating conundrums, explained.
3. They support healthy digestion.*
The friendly bacteria in your gut are key players in the breakdown and digestion of fiber-rich carbohydrates (sometimes called prebiotics). During the breakdown process, gut bacteria produce short-chain fatty acids (SCFAs), like butyrate, which serves as fuel for the cells that line and strengthen the barrier of the intestine.
As gastroenterologist Will Bulsiewicz, M.D., MSCI, explains, "SCFAs are a real game-changer with the potential to legitimately transform the health of those who pursue it."* And a healthy butyrate level, a type of SCFA, is thought to protect against a number of health issues, as well as obesity—perhaps by helping to better manage the body's inflammatory response.*
4. They have skin benefits.*
Probiotics don't just work wonders inside your body; they can actually affect the outside as well.* "You have bacteria on your skin and all over your body. Probiotics on the skin affect the microbiome that's present on your skin, as opposed to the one in your gut," says integrative medicine expert Amy Shah, M.D.
Friendly bacteria produce antimicrobial substances that do battle with harmful skin pathogens, research shows.* This nutritional support could help manage problems like eczema, acne, allergic inflammation, and hypersensitivity, as well as promote wound healing and help fight skin damage.* In this case, both oral and topical probiotics can help.
5. They can affect emotional health, too.*
Probiotics seem to reduce the body's stress response and affect cognitive function, several studies have found.* How? The mechanisms are complex, but good bacteria in the gut are capable of producing mood-stabilizing neurotransmitters, like serotonin and dopamine.* And because these bugs have a direct link to the central nervous system, via a pathway called the vagus nerve, they play a role in regulating mood.*
And that can have real effects: In one study, when women were shown pictures of angry faces, those who ate probiotic yogurt twice a day for four weeks before seeing the pictures felt calmer compared to those women who didn't eat the yogurt.*
6. They're heart-healthy.*
Believe it or not, the benefits of probiotics can even extend to your ticker.* Case in point: A review of more than 30 randomized clinical trials found that taking probiotic supplements can significantly and positively affect total cholesterol levels.*
There are also benefits to blood pressure: Consuming probiotics can benefit both systolic (the top number) and diastolic (the bottom number) blood pressure about the same as from eating a low-salt diet, a recent analysis concluded.*
Probiotics for women.
Can getting more probiotics also help your vaginal microbiome? Infections like bacterial vaginosis and yeast infections can occur when bad bacteria inside your vagina outnumber the good.
With that in mind, it might follow that getting more good bacteria in the form of food and probiotic supplements could help combat these problems.* And indeed, a few small studies have shown that taking an oral probiotic or a probiotic-antibiotic combo could help manage bacterial vaginosis.* And regular yogurt consumption, a probiotic-rich food, is tied to healthier levels of vaginal bacteria as well.*
Probiotics could also prove beneficial during pregnancy.* Since 2015, the World Health Organization has recommended that pregnant women at high risk for having a child with allergies take a probiotic supplement, particularly to reduce their child's chances for developing eczema.* For women with gestational diabetes, supplementing with probiotics has been shown to significantly benefit insulin resistance and fasting blood sugar.*
Probiotics for men.
Is what's good for the gut also good for the gonads? When it comes to couples who are trying to get pregnant, the science is promising.* A handful of studies have found that supplementing with a blend of probiotics and prebiotics (fibers that act as food for probiotics) could significantly improve sperm quality and raise testosterone levels in men struggling with fertility issues.*
Picking a probiotic: What to look for.
Targeted strains to reset your gut, beat bloating, and help reduce waist circumference.*
There are lots and lots of different bacteria strains that fall under the probiotic category. And while a lot of products take the "kitchen sink" approach of throwing a lot of different strains into one capsule, "different strains can be tied to different benefits," explains functional dietitian Krista King, M.S., RDN, LDN. So if you're thinking about taking a probiotic, then it makes sense to seek out a supplement with a strain that's been shown to have potential in meeting your needs.
Experts are still studying how different probiotic strains deliver their unique benefits. Here's a brief look at what the research has uncovered so far:
- For general health support: Lactobacillus, Bifidobacterium, and Saccharomyces Boulardii.*
- For diarrhea: Lactobacillus rhamnosus GG, Lactobacillus acidophilus, and Lactobacillus bulgaricus.*
- For weight maintenance: Lactobacillus gasseri, Lactobacillus rhamnosus, and Bifidobacterium lactis.*
- For mood support: Bifidobacterium longum, Bifidobacterium breve, Bifidobacterium infantis, Lactobacillus helveticus, and Lactobacillus rhamnosus.*
- For heart health: Lactobacillus acidophilus, Lactobacillus plantarum, and Bifidobacterium lactis.*
- For bloat: Lactobacillus Acidophilus and Bifidobacterium lactis. *
Aside from the probiotic strains themselves, also pay attention to the number of colony-forming units (CFUs) listed on the product label. (A typical probiotic supplement contains anywhere from 1 to 50 billion CFUs per dose.) Higher CFU counts aren't necessarily more potent than lower ones, though, say the National Institutes of Health. As Rountree sums it up, "More doesn't necessarily equal better." Adding, "You want something that's got a good stability, got a good shelf life, and then you want to have strains that have actually been well researched."
It is important to seek out products that list their CFU count on the label's expiration date, though. (Beyond that date, it's not guaranteed that the product will have the amount of CFUs listed on the label, King says.) If a probiotic only lists the CFU count "at the time of manufacture," then there's no guarantee the product will still be as potent by the time you use it.
No matter what product you end up choosing, you'll want to follow the storage directions to keep your product as potent as possible. "Some probiotics will need to be refrigerated while others may just need to be stored in a cool, dry place," King says.
Should everyone take a probiotic?
Probiotics are generally regarded as safe to take if you're healthy according to the NCCIH. But if you have a serious illness or a compromised immune system, then you'll want to first get the green light from your doctor.
As for how much you should take—and how often? If you're generally healthy, it's fine to take a probiotic supplement every day, King says. It's also worth incorporating probiotic-filled foods into your diet—think yogurt, kefir, sauerkraut, kimchi, or tempeh.
There's no standard dosage that's right for everyone, though, so consider talking with your doctor or a registered dietitian who specializes in functional eating. They will be able to offer more specific guidance based on the health issue you're trying to address.
Finally, pay attention to how your probiotic supplement makes you feel. If the symptoms you're trying to manage seem to get worse instead of better or you start to experience stomach discomfort, then that could be a sign that the particular probiotic strain doesn't agree with you, King says. In that case, you should take a break and consider trying another strain.
The gut microbiome is made up of trillions of bacteria living in your small intestine. These bacteria are involved in a wide range of functions in the body, supporting the immune system, digestive system, and more.* Taking a probiotic supplement or eating probiotic-rich foods can help support good bacteria in the gut and can be beneficial for overall health.*