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Lactobacillus acidophilus is a probiotic bacteria. Research suggests that consuming probiotics can be good for digestion and general health.

L. acidophilus occurs naturally in the human body as well as many fermented foods, such as sauerkraut and miso. Manufacturers also add L. acidophilus to yogurt and other dairy products.

Probiotics are beneficial strains of live yeast and bacteria. Studies indicate that consuming probiotics, such as L. acidophilus, can help support digestion and may offer a range of other health benefits.

In this article, we explore the potential health benefits of L. acidophilus. We also cover side effects, sources, and how to use this probiotic.

Red miso on a spoon that contains lactobacillus acidophilusShare on Pinterest
Miso, sauerkraut, and kefir contain L. acidophilus.

L. acidophilus is a probiotic bacteria that naturally occurs in the human gut and other parts of the body. This bacteria helps the digestive system break down sugars, such as lactose, into lactic acid.

Trillions of bacteria and other micro-organisms live in every person’s gut. Research indicates that consuming probiotics can help improve the balance between the beneficial and harmful bacteria that live in the gut. This may help to support digestion as well as provide other health benefits, such as boosting the immune system.

According to the National Cancer Institute, L. acidophilus may also help protect against harmful germs. This is because they create an acidic environment that the germs do not like.

L. acidophilus is present in a variety of foods and is also widely available as a dietary supplement. Supporters of this probiotic claim it provides a wide range of health benefits, from preventing yeast infections to curing cancer.

As with any health food or supplement, it is important to be a critical consumer. Research does indicate some health benefits from consuming L. acidophilus, but studies do not support every suggested benefit.

Some evidence suggests that L. acidophilus might be beneficial for a range of disorders and conditions, including:

Depression

Emerging research suggests that the health of the gut might also have an impact on the brain.

A 2013 study, for instance, found that gut bacteria can influence brain chemistry, suggesting a possible link between gut health and depression. Also, a 2016 systematic review indicates that taking probiotics, such as L. acidophilus, may lower the risk of getting depression or even help treat symptoms in people with depression.

Chronic fatigue syndrome (CFS)

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CFS can cause extreme tiredness and make a person feel generally unwell.

CFS is a long-term condition that can cause a variety of different symptoms, such as:

  • extreme tiredness and lethargy
  • concentration and memory difficulties
  • muscle or joint pain
  • feeling generally unwell
  • sleep problems

Doctors do not fully understand CFS or what causes it. However, some researchers believe that gut health, and specifically gut bacteria, may play a role in its development.

In a 2012 study, researchers induced CFS-like symptoms in rats. The study found that giving the rats L. acidophilus significantly reduced these symptoms.

Lactose intolerance

L. acidophilus helps the body metabolize and break down lactose. Lactose is a sugar found in milk and other dairy products. According to the U.S. National Library of Medicine, around 65 percent of adults worldwide find it difficult to digest lactose following infancy. Lactose intolerance can cause intestinal pain, diarrhea, gas, and bloating.

L. acidophilus supplements may help relieve the effects of lactose intolerance by helping the body metabolize lactose. A 2016 study compared taking L. acidophilus supplements with a placebo in people with lactose intolerance. Following 4 weeks of supplementation, people who took L. acidophilus had statistically significant reductions in symptoms of lactose intolerance, such as cramping and vomiting.

Irritable bowel syndrome (IBS)

IBS is a long-term digestive disorder that can cause diarrhea, constipation, bloating, and other symptoms. Doctors do not fully understand what causes it, and there is currently no cure.

The gut microbiota is the community of bacteria and other microbes that live in the stomach and intestines. Research is beginning to suggest that problems with the natural balance of the gut microbiota may play a role in the development of IBS.

Several studies reveal that consuming L. acidophilus and other probiotics may improve symptoms of IBS. However, the studies have been small, and researchers do not fully understand the role of gut microbes in IBS.

Yeast infections

Overgrowth of Candida, a type of yeast that occurs naturally on the human body, can cause itching and painful skin. Vaginal yeast infections are common, and it can take several days for over-the-counter or prescription remedies to work.

Some people notice that they get yeast infections following treatment with antibiotics. This may be because the drugs kill both good and bad bacteria.

Several studies suggest that probiotics may help prevent vaginal yeast infections and possibly other vaginal infections. For instance, a 2015 study suggests that taking Lactobacillus-containing probiotic supplements in combination with antibiotic and antifungal treatments may improve cure rates in women with yeast infections and bacterial vaginosis.

Inflammatory bowel disease (IBD)

Crohn’s disease and ulcerative colitis are types of IBD. They are long-term conditions that cause inflammation in parts of the digestive tract. Symptoms can vary considerably, but typically include diarrhea, cramping, and weight loss.

Some studies suggest that probiotic treatment may help manage these conditions. For instance, a 2013 meta-analysis, which examined the results of 23 randomized controlled trials, found higher rates of symptom-free periods among people with active ulcerative colitis who used probiotics.

Immunity

Animal studies suggest that consuming probiotics may boost the immune system. A 2015 study, for example, found that adding L. acidophilus to the diet of black swordtail fish supported their immune system in several ways.

The swordtails were less affected by stress, and their gut microbiota was stronger. The probiotic also improved the health of their skin mucus, which provides an important barrier to infections.

For people who are generally healthy, L. acidophilus and other probiotics are safe, and side effects are typically minimal. However, some people do report gas, bloating, and other mild digestive complaints.

Anyone considering supplementation with L. acidophilus or other probiotics should consult a medical professional first, especially if a person has health problems.

People with a serious underlying health condition may require close monitoring while taking probiotics as they may increase the risk of more severe side effects, including dangerous infections. This includes:

  • critically ill people
  • very sick infants
  • people who have recently had surgery
  • those with weakened immune systems

Because probiotics are available as foods and dietary supplements, the U.S. Food and Drug Administration (FDA) do not regulate them as strictly as prescription and over-the-counter medicines. Different brands and strains boast different strengths. It is, therefore, essential to choose a reputable brand, and to check the ingredients list for potential allergens.

If a person has any concerns about taking a probiotic, they should speak to a medical professional for advice.

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L. acidophilus occurs naturally in kombucha.

Manufacturers add L. acidophilus to yogurt and many other dairy products. It also occurs naturally in a range of fermented foods and pickles, including:

  • kombucha
  • some cottage cheese
  • kefir
  • sauerkraut
  • miso
  • tempeh

Dietary supplements containing L. acidophilus are also widely available from health stores and pharmacies. A range of these dietary supplements is also available to purchase online.

People can easily add L. acidophilus and other probiotics to their diet. A convenient and popular way of doing this is through yogurts and yogurt drinks, but some other fermented foods also contain L. acidophilus. However, always check the label to ensure the product does contain L. acidophilus.

When taking L. acidophilus dietary supplements, choose a reputable brand, and always follow the package directions. A doctor, pharmacist, or herbalist can also help with choosing the right L. acidophilus supplement.

L. acidophilus is a well-tested probiotic that is safe for most people. Research suggests that probiotics can support digestion and may help prevent or treat some other conditions.

Some individuals use L. acidophilus as a general health aid, while others take it to treat specific medical conditions, such as IBS or IBD. Both uses are generally safe.

Anyone who experiences side effects or a worsening of existing symptoms should stop using L. acidophilus and see a doctor.