Updated: Jul 13
Found naturally in your intestines, Lactobacillus Acidophilus is one of the best-known probiotics. Beneficial micro-organisms that may promote health and protect against infections.
Lactobacillus Acidophilus balances potentially harmful bacteria that can otherwise flourish in the gut due to illness or antibiotics. It may also help balance flora in the vagina, helping to prevent yeast infections.
Commonly found in yogurt and other fermented foods, it is also available in supplement form.
L. acidophilus belongs to the Lactobacillus family of bacteria. Lactic acid bacteria (or L) convert sugars into lactic acid and hydrogen peroxide, substances that inhibit the growth of undesirable bacteria in the intestines.
In alternative medicine, Acidophilus is sometimes used to prevent or treat several health conditions, including:
C. difficile infection
Candida infection (yeast infection)3
E. coli infection
Irritable bowel syndrome (IBS)
Urinary tract infection (UTI)
Some proponents also claim that Acidophilus can promote weight loss and strengthen the immune system.
Although Acidophilus is one of the more extensively studied probiotics, findings have varied widely due to differences in patient populations, Acidophilus strains, and other factors.
Here is a look at some findings from the available research on the benefits of Lactobacillus Acidophilus.
Acidophilus has been recommended in alternative medicine as a potential treatment for diarrhoea. Research suggests it may help to prevent C. difficile-associated diarrhoea, a type of severe diarrhoea that often affects older adults in medical care facilities who require broad-spectrum antibiotic treatment.
In a research review published in the Cochrane Database of Systematic Reviews in 2017, scientists analysed 31 previously published trials on the use of various types of probiotics to prevent C. difficile-associated diarrhoea.
It concluded that short-term, prophylactic use of probiotic supplements while taking broad-spectrum antibiotics is safe and effective for preventing C. diff infections in people who do not have weakened immune systems or are not severely debilitated.
Probiotics have also been found to be potentially useful in treating diarrhoea from other causes as well. One study, which focused on probiotic use in children under 2 years of age with rotavirus, found Acidophilus and other probiotics significantly reduced the duration of diarrhoea compared to a placebo.
An older review of published research found probiotics may be effective in reducing the severity of traveller’s diarrhoea, antibiotic-related diarrhoea, and acute diarrhoea of other causes. Additional research found acidophilus and other probiotics may reduce diarrhoea caused by radiation treatments, a common side effect of pelvic radiotherapy.
Irritable Bowel Syndrome
Probiotics including acidophilus have been touted as a treatment for irritable bowel syndrome (IBS). However, the research is mixed.
One eight-week study of people with IBS found a probiotic combination of L. Acidophilus and Bifidobacterium lactis noticeably relieved IBS symptoms at four and eight weeks compared to a placebo. But a six-month clinical trial found a combination of probiotics that included Acidophilus had no beneficial effect on diarrhea in people with IBS.
Still another study found the probiotics appear to work best to relieve symptoms of IBS when they are taken in single strain doses of less than 10 billion colony-forming units (CFUs) per day for less than eight weeks.
L. acidophilus may be helpful in the prevention and treatment of vaginal infections. According to a 2014 review, Lactobacillus supplements (including acidophilus) taken daily may help prevent and treat bacterial vaginosis, a common vaginal infection that results from an imbalance in the types of bacteria (flora) in the vagina.
Acidophilus is commonly recommended for the prevention of yeast infections while taking antibiotics. Laboratory research shows the probiotic inhibits the growth of Candida Albicans in cell cultures, but little research has been done in humans. A 2015 clinical trial published in the journal Probiotics and Antimicrobial Proteins found L. acidophilus can help to prevent recurring yeast infections following standard medical treatment. In the study, 436 women with vaginal candidiasis were treated with the antifungal Fenticonazole. Five days later, roughly half the subjects were treated with multiple intravaginal L. acidophilus treatments. Those given the probiotic had a significant reduction in recurring infections.
Acidophilus has antimicrobial and antiviral properties and may help to prevent colds, viruses, and even allergies. There is research to suggest probiotics, including acidophilus, may reduce cold symptoms in children.
A study published in the journal Pediatrics found six months of daily L. acidophilus probiotics reduced fever by 53%, coughing by 41%, antibiotic use by 68%, and days absent from school by 32%. Combining acidophilus with a broad spectrum of probiotics was found to be even more effective.
Studies suggest that probiotics may help cut cholesterol levels, and acidophilus appears to be more effective than other species.
A 2015 literature review published in the Annals of Medicine concluded that probiotic supplements containing L. acidophilus were effective in lowering total cholesterol and LDL ("bad") cholesterol levels. The review of 15 studies involving 788 subjects also found the probiotic improved factors associated with cardiovascular disease, including body mass index, waist circumference, and inflammatory markers. Compared to other strains, acidophilus was found to be more effective in reducing LDL levels. These results were confirmed in a review published in the journal Medicine in 2015. Researchers analysed 30 randomized controlled trials with 1,624 participants and found probiotics lowered total cholesterol and LDL cholesterol by 7.8 mg/dL and 7.3 mg/dL, respectively.
Some probiotic proponents claim that supplementing with probiotics like L. acidophilus can promote weight loss, but the research is conflicting. While it shows promise in animal trials, human trials have inconclusive results.
Various probiotics are being studied for their potential to reduce blood sugar in people with diabetes. It is believed that the beneficial bacteria may improve carbohydrate metabolism.
A 2016 review of seven published studies of people with type 2 diabetes found those who took probiotics for at least eight weeks decreased fasting blood sugar by 16 mg/dl and A1C levels by 0.53 percentage points compared to placebo groups.18 Subjects taking a broad spectrum of probiotics experienced a 35 mg/dl drop in fasting glucose levels. The research focused on various probiotics; it is unclear if acidophilus alone is beneficial for blood sugar management.
Emerging research suggests probiotics including L. acidophilus may help prevent and treat depression. Scientists have found a link between the gut and emotional health and taking probiotics may improve intestinal health. A 2016 literature review published in the journal, Nutrients, found that probiotics were associated with a significant reduction in depression and should be studied further as a potential preventive strategy for the condition.
Possible Side Effects
Common side effects include digestive complaints, such as gas, bloating, upset stomach, or diarrhoea. Although most digestive side effects decrease with use. In addition to this, acidophilus may weaken tooth enamel over time when exposed to teeth. Serious side effects are rare. However, if you experience hives, skin rash, itching, difficulty breathing, vomiting, or swelling of your face, lips, tongue, or throat, stop using L. acidophilus and seek immediate medical attention.
If you are pregnant or breastfeeding, speak to your doctor before taking acidophilus. You should consult your paediatrician before giving acidophilus to children, babies, or infants. Children who are ill, premature infants, and children with weakened immune systems are at a greater risk for adverse events and complications.
There is some concern that acidophilus can raise the risk of D-lactate toxicity. People who have had gastric bypass surgery or who have any of the following issues may be at greater risk: Short bowel syndrome, Small intestine bacterial overgrowth (SIBO), Thiamine deficiency, Kidney failure, Diabetes,
People with a weak or impaired immune system due to a medical condition, or immune-suppressing treatment or medication, should not take acidophilus.
Likewise, you should not take acidophilus if you have an artificial heart valve, heart valve disorder, or central venous catheter due to the risk of infection.
You will also need to avoid acidophilus if you have a condition resulting in intestinal damage, due to the risk that the bacteria could escape into other parts of the body and potentially cause serious complications such as bacteraemia or sepsis. There have been reports of other Lactobacillus species being involved in infections such as abscesses and meningitis.
Dosage and Preparation
Acidophilus supplements are sold in a variety of forms: capsules, tablets, drinks, pearls, powders, chewable wafers, liquids, and suppositories.
The typical adult dose is 500 million living organisms known as colony-forming units (CFUs), taken once daily.
If giving L. acidophilus to a child, check with their paediatrician about an appropriate dose or purchase a brand formulated for children and follow the directions on the packaging.
Natural Food Sources of Acidophilus
Kimchi (a traditional Korean fermented cabbage dish)
Kombucha (a fermented tea)
Fermented soy products such as miso and tempeh
While acidophilus may seem harmless because it is found naturally in the body and in many common foods, supplementation is not right for everyone. If you are considering taking acidophilus for any condition, it is a good idea to consult with your healthcare provider to confirm if it is appropriate and safe for you.