What Is Lactobacillus Acidophilus?

Medically reviewed by Suzanne Fisher, RD

Lactobacillus acidophilus (Lactobacillus or L. acidophilus) is a type of beneficial bacteria that’s naturally found in the body. It’s also commonly taken in a probiotic supplement form to support various aspects of health.

Lactobacillus works by helping balance out the bacterial environment in the body–and research shows that it’s likely beneficial for improving issues like diarrhea, irritable bowel syndrome (IBS) symptoms, certain vaginal infections, and more.

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Benefits of Lactobacillus Acidophilus

Lactobacillus acidophilus as a supplement mainly works in the gastrointestinal tract, but it has a variety of potential uses for different health conditions.

Relieves Diarrhea

By keeping the digestive tract bacteria balanced, Lactobacillus appears helpful as a supportive treatment for diarrhea. It’s been shown to help relieve diarrhea that is acute (short-term), chronic (long-lasting), and caused by antibiotics.

Experts theorize that probiotics like Lactobacillus work by repopulating and encouraging the balance of healthy bacteria in the gut, which can reduce diarrhea and gastrointestinal discomfort. One research review found that Lactobacillus helped shorten the duration of a bout of diarrhea in children compared to taking a placebo.

May Reduce Irritable Bowel Syndrome Symptoms

Irritable bowel syndrome (IBS) is a gastrointestinal disorder that can cause pain and discomfort in the stomach, as well as increased diarrhea, gas, or constipation. Lactobacillus supplements may be able to assist in relieving these symptoms.

Some research suggests that Lactobacillus may be beneficial for relieving IBS-related stomach pain, in addition to reducing the severity of IBS symptoms. More studies are needed to confirm these findings, however, as researchers note Lactobacillus may also have the potential to produce unwanted side effects in some people with IBS.

Prevents Vaginal Infections

Lactobacillus may be an effective prevention or treatment method for vaginal infections like bacterial vaginosis (BV) and yeast infection.

At least one study found that taking the probiotic daily helped prevent and treat BV, which is a common vaginal infection that happens when there’s an imbalance in the vagina’s bacterial environment.

Other research has shown that Lactobacillus may prevent the yeast infection-causing fungus Candida albicans from growing and could help reduce the risk of getting recurring yeast infections post-medical treatment. Experts attribute this to the bacteria strain’s potential antimicrobial and antifungal properties.

Improves Cholesterol Levels

Researchers are looking into ways that Lactobacillus can help support healthy cholesterol levels.

Some studies have shown Lactobacillus may play a role in reducing the amount of cholesterol the body absorbs from the diet, lowering cholesterol levels overall. Research has also found Lactobacillus was more effective at reducing total cholesterol levels than other strains of probiotics.

Potentially Supports Immune Health

Research has found Lactobacillus has potential anti-inflammatory, antimicrobial, and antiviral properties, meaning it could help support immune system health.

This probiotic strain likely helps improve immune function by enhancing the gut barrier and white blood cell activity, which are functions that protect the body from infection and other toxins.

Initial findings suggest taking the probiotic may help support against certain viruses like COVID-19, pneumonia, and other respiratory infections. However, much more scientific evidence is needed to support this theory.

How To Take Lactobacillus Acidophilus

Lactobacillus supplements come in the form of capsules, chewable tablets, powders, beverages, and suppositories (for vaginal use). Some research suggests that Lactobacillus products may work best when taken with a meal, or right before a meal.

Dosage

There isn’t a standard dosage recommendation for Lactobacillus. Probiotics are measured by a metric known as colony forming units (CFUs), which represents the number of living cells of microbes within the product.

Experts may suggest adults take oral doses of 60 billion CFUs per day for up to six months, and children take up to 30 billion CFUs per day for up to three months. Also, the product’s label can help you determine whether Lactobacillus is the only stain of bacteria making up the supplement, or if there are multiple strains or species of bacteria included.

Check with a healthcare provider to discuss what may be the best dose for you and your individual needs and health concerns.

Is Lactobacillus Acidophilus Safe?

Lactobacillus is considered generally safe when taken orally (by mouth) and applied topically (like to the vaginal area). However, people who are pregnant, breastfeeding, or have certain health conditions may need to consult a healthcare provider first.

The following groups of people should keep these considerations in mind before trying Lactobacillus:

• People who are pregnant: While Lactobacillus is possibly safe in supplement form during certain weeks of pregnancy, always check with a healthcare provider before adding any new supplements to your routine while pregnant.
• People who are breastfeeding: There isn’t enough evidence to determine whether Lactobacillus is safe to use while breastfeeding.
• Children: Lactobacillus is likely safe in supplement form for most healthy children, but more data is needed on its safety in infants (particularly in premature infants).
• People with a weakened immune system: Because probiotics have the rare potential to cause a blood infection in some people with a weakened immune system, ask a healthcare provider before trying Lactobacillus if this is your situation.
• People with damaged heart valves: In extremely rare cases, probiotics have triggered infections in the inner lining of the heart valve. A healthcare provider can advise whether Lactobacillus is safe for people who have a damaged heart valve.

Potential Drug Interactions

Lactobacillus isn’t known to have severe interactions with medications, but taking certain medications at the same time as this supplement may interfere with the effectiveness of the probiotic.

For example, because antibiotics are prescribed to reduce harmful bacteria in the body, taking them while taking Lactobacillus may reduce the probiotic’s intended effects.

If you’re taking antibiotics or antifungal drugs, check with a healthcare provider to see if you should continue using Lactobacillus supplements during that time. They may recommend taking the probiotic several hours before or after the prescribed medication to help reduce interactions.

What To Look For

Lactobacillus is added to some food products and is available as a dietary supplement—but keep in mind that supplements are not regulated by the U.S. Food and Drug Administration (FDA) in the same way foods and medications are.

When buying a probiotic supplement, look for a seal on the bottle that states the product has undergone third-party testing for product potency and purity. Reputable third-party testers include U.S. Pharmacopeia and ConsumerLab.com.

Also, pay close attention to the probiotic’s name, as it’s possible to confuse Lactobacillus with other probiotics that are not the same bacterial strain. You should also check if the supplement contains only Lactobacillus or a mix of various probiotic strains.

Can You Take Too Much Lactobacillus Acidophilus?

There isn’t an established dose recommendation or daily limit for taking probiotics. However, consuming excess Lactobacillus—or any other probiotic supplement—may increase the chances of experiencing common gastrointestinal side effects.

When taking a probiotic supplement, make sure to follow the dosage listed by the manufacturer or given by a healthcare provider.

Side Effects of Lactobacillus Acidophilus

There are a few potential side effects that may come along with taking Lactobacillus supplements.

Common and mild side effects include:

• Gas
• Bloating
• Vaginal discharge (when used topically on the vaginal area)

More rare and severe side effects include blood infections, particularly in people who have a compromised immune system, as well as an infection of the inner lining of the heart, particularly in people who have a damaged heart valve.

A Quick Review

Lactobacillus acidophilus is a type of good bacteria that’s been shown to have gut, vaginal, and immune health benefits. This bacteria is naturally found in the body but is also available in supplement form.

While Lactobacillus is generally considered safe for most people, always consult a healthcare provider before adding this probiotic to your daily routine.

Read the original article on Health.com.