Introduction
Probiotics refer to “live microbial food supplements or components of bacteria which have been shown to have beneficial effects on human health” (Salminen, Bouley, Boutron-Ruault, Cummings, Franck, & Gibson 1998, p. 148). Early scientists such as Hippocrates saw fermented milk products like yogurt as a source of food and medicine. This is how sour milk is found used as a solution to the stomach and intestinal disorders (Lourens-Hattingh & Viljoen 2001). Scientists first became interested in probiotics and the role that they play in human health as far back as 1908. During this time, Metchnikoff, a Russian bacteriologist, proposed that man should consume fermented milk to prolong life (Harish & Varghese 2006).
However, scientists took along to understand the link between the health benefits of intestinal microorganisms. Currently, scientists appear to agree that maintaining the microbial population of an individual’s digestive tract at optimal ‘balance’ is also linked to good health and nutrition (World Cancer Research Fund / American Institute for Cancer Research 2007).
‘Probiotics’ defined
The term Probiotics is a derivative of a Greek word that means, ‘for life’. Probiotics products like yogurt contain live microorganisms that are essential in improving the health status of an individual. As we age, the equilibrium of our intestinal microflora is destabilized, with the “bad bacteria” replacing “good bacteria”. Consuming probiotics restore this balance (Salminen et al. 1998). Although humans have natural probiotics in their bodies, factors such as stress, poor diet, and hormonal imbalances tend to destabilize these levels (British Nutrition Foundation 2013). Therefore, we must boost these levels by consuming food supplements rich in probiotics (Ataie-Jafari et al. 2009).
Viable Bifidobacterium bifidum and Lactobacillus acidophilus cells in bio-yogurt assist in the delivery of the desired goals (Anderson & Gilliand 1999). Metchnikoff proposed the ‘longevity-without-aging theory which holds that the conversion of lactose in milk into galactose and lactic acid through fermentation using live bacteria helps to displace toxin-producing bacteria in the gut (Anderson & Gilliand 1999). Although earlier work on the role of lactic cultures in foods mainly dwelt on the treatment of intestinal infections, the focus has now shifted to other health benefits, including their role in combating flu, bad breath, and allergies.
Nutritional Content
It is important to note that the nutritional content of yogurt is superior to that of fresh milk and other foods. The most notable nutrients in yogurt are riboflavin, calcium, as well as vitamin B 12, and vitamin B6 (Webb 2006). The addition of the starter culture in yogurt enhances its nutritional benefits (Lourens-Hattingh & Viljoen 2001). Besides, the conversion of lactose (the simple sugar in milk) to glucose and galactose along with the particle fermentation of the by-products to lactic acid means that even lactose-intolerant people can consume it. It is also important to note that live cultures in yogurt prevent constipation, diarrhea, as well as allergies, colds, and flu. Unlike milk, the fat content of yogurt differs based on the manufacturing process and the intended purpose of the end-products.
Effectiveness of yogurt as a functional food
Probiotic bacteria like lactobacilli and bifidobacteria found in milk have beneficial antimicrobial properties. For example, both Bifidobactrium bifidum and Lactobacillus acidophilus found in yogurt contain inhibitory properties that help to wade off most food-borne pathogens common to man (Atkinson 2010).
Several studies show that administering milk cultured with Bifidobactrium bifidum or Lactobacillus acidophilus controls various intestinal infections. These bacteria inhibit pathogens by either stimulating the immune system or producing antimicrobial/inhibitory substances like antibiotics and hydrogen peroxide. Besides, probiotic bacteria displace pathogens from their adhesion sites in the gut.
Several studies indicate that fermented milk products such as yogurt reduce serum cholesterol levels among individuals. This is important to hypercholesterolemic individuals because it minimizes their risk of developing heart attacks. Probiotics have also been associated with the suppression of procarcinogens and/or carcinogens (Atkinson 2010).
Several studies have demonstrated that regular intake of fermented milk or yogurt helps to inhibit both the formation and proliferation of tumors (World Cancer Research Fund / American Institute for Cancer Research 2007). Recent research studies show that probiotics have additional benefits over and above their well-known role in the gut, like in the treatment of fibromyalgia, type-1 diabetes, and in improving weight loss (Atkinson 2010). Researchers have also developed probiotic lozenges to help overcome sore throats.
Probiotics have also been found used as a remedy to dental cavities. Plans are also underway to develop probiotic nasal sprays.
Probiotics are important in the absorption of nutrients during digestion, especially in peristalsis. They stimulate mucins production, thus playing a crucial role in protecting our ‘inside’ skin by lubricating it. Probiotics are also involved in the secretion of useful nutrients that aid in tissue repair.
It is also important to underscore the important role of probiotics in reducing vaginal and bladder infections by upholding the right bacteria balances. Bad bacteria also cause most body odors, including bad breath (Atkinson 2010). This results in unhealthy gums, rotting teeth, ulcer bacteria, and poor digestion ensues. Adding fermented milk products like yogurt with probiotic properties can act as a remedy to this.
Live cultures in yogurt help to resolve sluggish bowel movements. Research indicates that individuals with allergies also tend to have compromised gut flora levels. The bacteria levels can be reset by consuming probiotics to act as a formidable and protecting barrier (Atkinson 2010). Studies show that individuals who take more fermented milk have better immunity to allergens like pollen compared with those who consume less fermented milk. Probiotics also help to boost the immune system, resulting in fewer winter infections and colds.
Conclusion
Probiotic yogurt is laden with important functional properties owing to the probiotics contained in the live cultures. Besides fighting infections, probiotic yogurt reduces serum cholesterol levels, aids in digestion, and improves immunity to allergens. By boosting the immune system, probiotics help to prevent colds and infections. Research is also underway to develop probiotics that can treat fibromyalgia and type-1 diabetes, in addition to suppressing carcinogens.
Reference List
Anderson, J W & Gilliand, S E 1999,’ Effect of fermented milk (yogurt) containing Lactobacillus acidophilus L1 on serum cholesterol in hypercholesterolemic human’, J Am Coll Nutr., vol. 18, pp. 43–50.
Ataie-Jafari, A, Larijani, B, Alavi, H & Tahbaz, M 2009,’ Cholesterol-lowering effect of probiotic yogurt in comparison with ordinary yogurt in mildly to moderately hypercholesterolemic subjects’, Ann Nutr Metab., vol. 54, pp. 22–27.
Atkinson, L 2010, The yoghurt cure: Probiotics are good for our digestion. But they can also combat flu, allergies and bad breath, Mail Online, pp. 1.
British Nutrition Foundation 2013, British Nutrition Foundation. Web.
Lourens-Hattingh, A & Viljoen, B C 2001,’ Yogurt as probiotic carrier food’, International Dairy Journal, vol. 11, pp. 1–17.
Harish, K & Varghese, T 2006,’ Probiotics in humans – evidence based review’, Calicut Medical Journal, vol. 4, no. 4, p. 3.
Salminen, S, Bouley, C, Boutron-Ruault, M C, Cummings, J H, Franck, A & Gibson G R et al. 1998,’ Functional food science and gastrointestinal physiology and function. British Journal of Nutrition., Vol. 80, pp. 147-71.
World Cancer Research Fund / American Institute for Cancer Research 2007, Food, Nutrition, Physical Activity and the Prevention of Cancer: a global perspective, AICR, Washington DC.