The Therapeutic Benefits of Lactobacillus Acidophilus
Many of us are familiar with Lactobacillus acidophilus as a commonly used preservative for food which also provides unique texture and flavour.  The advent of nutritional research have found that Lactobacillus acidophilus has several health benefits.
Just before discussing those, it is imperative to know few background information about Lactobacillus acidophilus.
What is Lactobacillus acidophilus?
Lactobacillus acidophilus is a type of lactic acid bacteria which rapidly ferments carbohydrates (sugar containing foods) and release lactic acids. This microorganism is classified under gram-positive bacteria. The rod-shaped Lactobacillus acidophilus is available in human guts and extensively found in dairy products. Lactobacillus acidophilus prefers mild acidic media (pH 5.5–6.0 ) within a temperature range from 37 °C to 45 °C.  Apart from the intestine, human oral and rectal tract provide a favourable environment for growth and multiplication of Lactobacillus acidophilus.  However, Lactobacillus acidophilus unable to synthesise amino acids and vitamins, which are necessary for their growth. Therefore, the nutrient-rich medium is required for their sufficient growth. 
History of Lactobacillus acidophilus
In the year 1890, the first Lactobacillus acidophilus was isolated from infant faeces and was recognised as Bacillus acidophilus , by the Nobel Prize winner Llya Metchnikoff.  Several scientific kinds of literature mention different strains of Lactobacillus acidophilus e.g. NCFM, NCK45, NCK56, N2, and RL8K, but US Food and Drug Administration (FDA) has approved Lactobacillus acidophilus NCFM to use it as an ingredient in dairy products, nutritional powders, and purposeful beverages. 
Importance of Balancing 'Good Bacteria' and 'Bad Bacteria' in our Gastrointestinal Tract
Different parts of our body, such as oral cavity, skin and hair, gastrointestinal tract and rectal area etc., when exposed, provide a favourable condition to grow both good and bad bacteria. The group of Lactobacilli is considered as 'good bacteria' which play an important role in maintaining the intestinal microbial ecosystem. The different lactobacilli strains start to grow and multiply in the gut wall within the very initial stage (from the first week onward) of life and provide protection against 'bad bacteria' (also known as pathogens), mitigates lactose intolerance, assists in bowel movement, prevents constipation, anticholesterolemic effect and boost immunity. The proper balancing of the bacterial ecosystem is required for healthy life. The human gut provides moisture, proper acidic media, nutritious environment, and ideal temperature to maintain intestinal ecology. The balanced intestinal ecosystem is essential for food digestion, essential vitamin synthesis, water absorption and fighting against harmful bacteria.  Lactobacilli provide a therapeutic and preventive effect by synthesising antimicrobial compounds and reducing gut pH by increasing production of lactic acid in microflora. It competes against pathogens to bind with receptor sites, activate immunomodulatory cells and utilise available nutrients. 
What is Probiotics?
The Probiotics; to go by prose means "for life",  as it is a supplementary form of 'good bacteria'. Probiotics are dietary supplements of good bacteria (live), which assists in balancing intestinal microbial system. Adequate consumption of probiotics provides multiple health benefits to the host body. Lactobacillus acidophilus is a commonly used 'good bacteria' strain used in 'Probiotics' formulations. 
Benefits of Lactobacillus acidophilus
Lactobacillus acidophilus is a conventional probiotic with multiple health benefits, as mentioned below:
Effective to Treat Gastrointestinal Diseases
Inflammatory bowel diseases (IBD) is one of the most common GI tract diseases caused by pathogenesis in the intestinal lumen. Lactobacillus acidophilus in form of probiotics, assist in modifying gut flora composition and alleviating mucosal inflammation by controlling platelet activating factor. Elevation of platelet activating factor is not the only indication of inflammatory bowel diseases, but also indicates Crohn’s disease, ulcerative colitis, and necrotizing enterocolitis by activating NF-κB (inflammatory agent) and other inflammatory stimuli. Therefore, administration of Lactobacillus acidophilus not only treats IBD but also provide protection against Crohn’s disease, ulcerative colitis, and necrotizing enterocolitis. 
Those who are suffering from allergic asthma; regular intake of L. acidophilus-rich products including yoghurt can help to inhibit eosinophilia, which stimulates an allergic reaction, increase the interferon-gamma level and provide promising effects against allergic-related immunopathologies. Thus L. acidophilus is effective in controlling allergy mediated severe asthma. 
Therapeutic benefit against allergies
Dr. Ishida Y, a well-known scientist from Calpis, Japan, in her research reported that Lactobacillus acidophilus-rich dairy products can provide symptomatic relief from allergic rhinitis. There are other studies that support Lactobacillus acidophilus to have a significant effect on allergy symptoms. 
Preventive action against vaginal infection
Vaginal alteration of pH is a triggering factor for altering vaginal ecosystem and resultant of this causes the onset of infection. Bacterial vaginosis and vaginal yeast infection are two most common vaginal infection. Research reports support that Lactobacillus acidophilus-rich foods, including yoghurt, has a therapeutic and preventive action against bacterial vaginosis and vaginal yeast infections. 
Immunity is the body's defensive mechanism, and to improve immunity is the basic fundamentals for healthy life. According to research reports, regular intake of Lactobacillus acidophilus can boost immune functionality and provide healthy life. Especially, children who frequently suffer from common cold, a twice daily intake of Lactobacillus acidophilus-containing food for three months can reduce the symptom, incidence rate and days of school absenteeism. 
Essential nutrients absorption and degradation
Polyphenols containing phytochemicals like rutin are obtained from different fruits and vegetables and have multiple health benefits, such as cardioprotective, anti-inflammatory, antioxidant and chemopreventive actions. However, we unable to avail most of these benefits due to their poor bioavailability. Lactobacillus acidophilus can increase absorption and degradation of these Polyphenols and improve bioavailability. 
Protection against gastrointestinal infection
Different pathogenic enterobacteria cause different types of gastrointestinal infections. Animal study result showed that probiotics containing Lactobacillus acidophilus can inhibit the growth of pathogenic enterobacteria by producing lactic acid, hydrogen peroxide (H202) and a bacteriocin. Thus, provide preventive and therapeutic effect against gastrointestinal infection. 
Lactobacillus acidophilus also offers relief from bloating symptoms(including bloating, distention, and gas) associated with bowel disorders. 
Today's hectic life, irregular food habits, adulterated food and exposure to pollution are mostly responsible for all these health related problems. Hence, it is very important to control our diet habits and maintain a balance in the physiological ecosystem. This can be done by having a healthy dose of Lactobacillus acidophilus-containing supplements and probiotics.
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