Acidophilus: What Are They and What Are Their Benefits?

Acidophilus are good bacteria that can help you improve your health. Check out the benefits of including them in your diet.
Acidophilus: What Are They and What Are Their Benefits?
Maria Patricia Pinero Corredor

Written and verified by the nutritionist Maria Patricia Pinero Corredor.

Last update: 25 July, 2022

Acidophilus are a group of bacteria that are a natural part of the intestines, mouth, and vagina. They’re characterized by belonging to the family of lactic acid bacteria, which are used in the elaboration of fermented foods and have clinical applications. They’re also part of the famous probiotics.

Part of their inclusion within the latter is due to how they help to maintain the intestinal microbiota. In addition, they’re so versatile that they’re used to treat vaginal inflammation, depression, and other disorders.

They’re found as freeze-dried bacteria in the form of capsules, tablets, powders, wafers, and even vaginal ovules. But they’re also part of many fermented foods, both of animal and vegetable origin.

In this article, we’ll address their benefits, where to find them, and how to consume them. So, stay with us as we show you how such a small bacterium can improve health.

What are acidophilus?

Acidophilus are a group of bacteria known in science as Lactobacillus acidophilus. They’re part of the normal flora of the vagina, mouth, and intestinal microflora. They’re classified as lactic acid bacteria, are fermenters, and don’t produce toxins.

They belong to the probiotics group because they benefit health. As noted in the BMJ, eating probiotics can improve digestion. They also protect against harmful germs by creating an acidic environment that isn’t favorable for pathogens.

These bacteria ferment carbohydrates (such as lactose) to lactic acid. Along with other bacteria, they’re also used in pharmaceuticals.

Acidophilus health benefits

Science shows that acidophilus can improve everything from a fungal infection to a mental health problem, such as depression. Let’s see what the main benefits are.

Relieves symptoms of lactose intolerance

The Spanish Journal of Digestive Diseases estimates that 80% of the world’s population suffers from lactose intolerance. Many of its symptoms are reminiscent of those of irritable bowel. These include gas, bloating, abdominal pain, and diarrhea.

Acidophilus in the form of supplements is able to alleviate the symptoms of intolerance by helping to break down lactose in food.

In a study published in the journal Nutrition Journal, a group of people with lactose intolerance took acidophilus supplements to combat symptoms. The results showed a reduction in abdominal cramps, vomiting, and diarrhea.

A person with lactose intolerance.
Patients with lactose intolerance may notice an improvement in their symptoms by taking acidophilus in supplement form.

Combat fungal and bacterial infections

Candidiasis is an infection caused by the overgrowth of a yeast naturally found in the body. The most common clinical form is a vaginal infection, which occurs with burning, itching, inflammation, and discharge.

Acidophilus lactobacilli are part of the normal flora of the vagina and produce lactic acid to keep the vagina at a slightly acidic pH. If the vagina loses acidity, then harmful bacteria can grow.

Webb Lauren’s study explains that acidophilus can help treat and prevent bacterial vaginosis. This occurs because they increase the amount of lactobacilli in the vagina, helping to restore the natural balance.

On the other hand, when long-term antibiotic treatments are taken, yeast infections can also occur. For this reason, acidophilus lactobacilli should be prescribed along with antibiotics to maintain the balance of the flora.

They could fight depression

For some time now, it has been discovered that intestinal bacteria have an influence on the chemicals released by the brain. Thus, a link has been established between gut health and depression.

A review on this topic concluded that probiotic consumption is associated with a significant reduction in depression. In addition, it states that acidophilus may decrease symptoms of this disease.

Improves inflammatory bowel disease (IBD)

Inflammatory bowel disease encompasses a group of chronic intestinal disorders of unknown cause. It includes ulcerative colitis and Crohn’s disease. Both are associated with diarrhea, cramping, and weight loss.

A meta-analysis of controlled trials found that probiotic administration produces an additional benefit by increasing symptom-free periods in patients with idiopathic ulcerative colitis.

Soothe irritable bowel syndrome (IBS)

Currently, the cause of IBS isn’t well understood. IBS is a digestive disorder that causes diarrhea, bloating, constipation, and other symptoms.

Research suggests that a lack of balance among the microorganisms that make up the gut microbiota may be a trigger.

A gastroenterology study found that acidophilus and other probiotics improve IBS symptoms. However, more research is needed to understand the role of the gut microbiota in this pathology.

They act on the immune system

A review reveals that probiotics can prevent or alleviate certain diseases of the gastrointestinal tract. They can even balance the functions of the microflora and modulate the immune response.

It is, therefore, suggested to use them as an alternative treatment in the prevention of diarrhea and in immune-dependent diseases, such as allergies, intestinal inflammations, and viral infections.

Improve symptoms of chronic fatigue syndrome (CFS)

Chronic fatigue syndrome is a disorder that causes a variety of symptoms, such as tiredness, lethargy, muscle or joint pain, general malaise, trouble sleeping, and difficulty concentrating.

Some health professionals claim that the cause of CFS has to do with the absence of gut health. In trials with laboratory rats that were induced with CFS, when given acidophilus, the symptoms disappeared. However, human studies are needed.

May control lung infections and eczema

Acidophilus may reduce the number and severity of respiratory infections in children. Acidophilus has also been shown to control atopic dermatitis in pregnancy, nursing mothers and infants when taken as a supplement.

A man with mental health problems.
The application in mental health is very promising. However, several mechanisms of action of acidophilins remain to be elucidated.

Sources of acidophilus and usage

Acidophilus are found in both food and supplements. Among the foods that provide these lactobacilli are the following:

  • Yogurt
  • Kefir
  • Tempeh
  • Miso
  • Sauerkraut
  • Kombucha
  • Cottage cheese

As supplements, they’re found in different presentations: tablets, capsules, powder, wafers, and ovules for vaginal infections.

Their usage will depend on what’s prescribed by the physician. The most common way is to ingest them through fermented milks and yogurts with probiotics.

It’s recommended to check the label of fermented foods and other vegetables to ensure that acidophilus are part of the strains planted in the food. For supplements, choose trusted brands and follow package directions.

Side effects

Acidophilus and other probiotics are safe and have almost no side effects. However, some people using them have reported gas, bloating, and other digestive upsets.

Unlike drugs, the U.S. Food and Drug Administration (FDA) isn’t as stringent in regulating probiotics. But some brands that keep the microorganism alive are recommended.

Certain health conditions, such as recent surgery or immunosuppression, require close monitoring while taking probiotics, as their intake could lead to complications. But only in these cases.

Can acidophilus be included in healthy diets?

Acidophilus are health-promoting bacteria that can be part of a healthy diet. They maintain a good intestinal and digestive function.

In addition, they can be used for the treatment of various diseases. You can find them in foods and supplements. You choose the best form of consumption after consulting with your health care provider.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Anjum, Nazia & Maqsood, Shabana & Masud, Tariq & Ahmad, Asif & Sohail, Asma & Ahmad, Abdul. (2014). Lactobacillus acidophilus : Characterization of the Species and Application in Food Production. Critical reviews in food science and nutrition. 54. 1241-51. 10.1080/10408398.2011.621169.
  • M Valdes,  Jens Walter,  Eran Segal,  Tim D Spector. Role of the gut microbiota in nutrition and health. BMJ 2018; 361:k2179, oi:
  • Michael N. Pakdaman , Jay K. Udani , Jhanna Pamela Molina  y Michael Shahani. he effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance – a randomized, double-blind, placebo-controlled, crossover clinical trial. Nutr J. 2016; 15: 56. Published online 2016 May 20. doi: 10.1186/s12937-016-0172-y PMCID: PMC4875742 PMID: 27207411
  • Departamento de Salud y Servicios Humanos de EE. UU. OASH. Candidiasis vaginal. Disponible en:
  • Webb, Lauren. Probiotics for preventing recurrent bacterial vaginosis.  JAAPA: February 2021 – Volume 34 – Issue 2 – p 19-22. doi: 10.1097/01.JAA.0000731484.81301.58
  • Huang R, Wang K, Hu J. Effect of Probiotics on Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2016; 8(8):483.
  • Añez Marianela, Fuenmayor Mildred, Romero Gisela. Enfermedad Inflamatoria Intestinal: Rectocolitis Úlcerosa Idiopática y Enfermedad de Crohn. Gen  [Internet]. 2012  Sep [citado  2022  Mayo  20] ;  66( 3 ): 197-206. Disponible en:
  • Jun Shen, MD, PhD, Zhi-Xiang Zuo, PhD, Ai-Ping Mao, PhD, Effect of Probiotics on Inducing Remission and Maintaining Therapy in Ulcerative Colitis, Crohn’s Disease, and Pouchitis: Meta-analysis of Randomized Controlled Trials, Inflammatory Bowel Diseases, Volume 20, Issue 1, 1 January 2014, Pages 21–35,
  • George Aragon , Deborah B. Graham ,Marie Borum , EdD,  y David B. Doman . Probiotic Therapy for Irritable Bowel Syndrome. Gastroenterol Hepatol (N Y). 2010 Jan; 6(1): 39–44.  PMCID: PMC2886445, PMID: 20567539
  • LuisP.Núñez Medin. PROBIOTICOS y SISTEMA INMUNITARlO INTESTINAL (1). Tema de revisión. Volumen 8 -Número 4 OCTUBRE -DICIEMBRE 2005. Disponible en:
  • K. Singh,K. Chopra,A. Kuhad,I. P. Kaur. Role of Lactobacillus acidophilusloaded floating beads in chronic fatigue syndrome: behavioral and biochemical evidences. Neurogastroenterology & Motility. Volume24, Issue4, April 2012, Pages 366-e170
  • Mayoclinic. Acidófilos. Disponible en:
  • National Center for Complementary and Integrative Health. NIH. Probiotics: What you need to know. Disponible en:

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.