What’s the story with probiotics in food? The NY Times features a piece on the topic on today’s front page. Seems like manufacturers are trying to cash in on the public’s hunger for better living through healthier food. Marketing scheme or the real deal?
Let’s start with the theory. A probiotic, from the Greek for "life," is defined by the American Journal of Clinical Nutrition as "a preparation of or a product containing viable, defined microorganisms in sufficient numbers, which alter the microflora (by implantation or colonization) in a compartment of the host and by that exert beneficial health effects in this host." This same article discusses the interesting history behind defining probiotics and the related terms prebiotics and synbiotics. I’ve listed other scientific references below as well. These organisms, numbering the millions in our intestinal tracts, are affected by genetics, what we eat, what medicines we take (i.e. antibiotics) and even our perceived level of stress. Alterations in our intestinal flora have been associated with such diverse conditions as irritable bowel syndrome, colic and eczema. Theoretically, by supplementing healthy live flora (lactobacillus species, bifidus species, among many others), we can support the damaged intestinal milieu. Researchers have demonstrated, in fact, that probiotics are immunologically active, and can positively shift our immune system reactions away from Th-2 dominant allergic/autoimmune predisposition and towards Th-1 dominant infection killing pathways.
Where does this leave us in the real world? Probiotics are becoming standard-of-care in the treatment and prevention of antibiotic-associated diarrhea, as well as other health conditions. Of course, like any other supplement, regulation is sketchy (see my last post), and product quality is variable. How do you know that what you buy on the shelf will still contain live, active, effective probiotics by the time you ingest it at home? Consumerlab.com has a nice review on the topic, and Consumer Reports (CR) did the same in July, 2005. There is a marked difference in product quality control. And with foods (most commonly yogurts), manufacturers would like us to believe that their products boost our health – yet their claims rely upon the assumption that probiotics are still live and effective in great number by the time you get home, put the food in the fridge, and eat it days later. As the International Scientific Association for Probiotics and Prebiotics (ISAPP), a noted scientific probiotic watchdog, pointed out in response to the CR story, we can’t be certain of what strains or number of organisms are present or useful in these food products. My advice is this – if you’re not dairy intolerant or allergic, go ahead, eat yogurt, it may be good for you. But if you want the best chance to see health benefits from probiotics, you are better off with refrigerated, high-quality supplements.
Alvarez-Olmos MI, Oberhelman RA: Probiotic agents and infectious diseases: a modern perspective on a traditional therapy. CID 32: 1567-1576, 2001.
Bibiloni R, et al: VSL#3 probiotic-mixture induces remission in patients with active ulcerative colitis. Am J Gastroenterol 100: 1539-46, 2005.
Bruzzese E, et al: Microflora in inflammatory bowel diseases: a pediatric perspective. J Clin Gastroenterol 38: S91-S93, 2004.
Charrois TL, et al: Probiotics. Pediatr Rev 27: 137-139, 2006.
Guandalini S: Use of Lactobacillus-GG in paediatric Crohn’s disease. Dig Liver Dis 34 S 2: S63-65, 2002.
Gupta P, et al: Is lactobacillus GG helpful in children with Crohn’s disease? Results of a preliminary, open-label study. J Pediatr Gastroenterol Nutr 31:453-457, 2000.
Johnston BC, Supina AL, Vohra S: Probiotics for pediatric antibiotic-associated diarrhea: a meta-analysis of randomized placebo-controlled trials. CMAJ 175: 377-383, 2006.
Kalliomaki M, et al: Probiotics in primary prevention of atopic disease: a randomised placebo-controlled trial. Lancet 357: 1076-1079, 2001.
Kalliomaki M, et al: Probiotics and prevention of atopic disease: 4-year follow-up of randomised placebo-controlled trial. Lancet 361: 1869-1871, 2003.
Kurugol Z, Koturoglu G: Effects of Saccharomyces boulardii in children with acute diarrhoea. Acta Paediatr 94: 44-47, 2005.
Lin H, et al: Oral probiotics reduce the incidence and severity of necrotizing enterocolitis in very low birth weight infants. Pediatrics 115: 1-4, 2005.
Lodinova-Zadnikova R, et al: Oral administration of probiotic Escherichia coli after birth reduces frequency of allergies and repeated infections later in life (after 10 and 20 years). Int Arch Allergy Immunol 131:209-211, 2003.
Madara J: Building an intestine – architectural contributions of commensal bacteria. N Engl J Med 351: 1685-1686, 2004.
McFarland LV: Meta-analysis of probiotics for the prevention of antibiotic associated diarrhea and the treatment of Clostridium difficile disease. Am J Gastroenterol 101: 812-822, 2006.
Moro G, et al: A mixture of prebiotic oligosaccharides reduces the incidence of atopic dermatitis during the first six months of age. Arch Dis Child 91: 814-819, 2006.
Murch SH: Probiotics as mainstream allergy therapy? Arch Dis Child 90: 881-882, 2005.
O’Mahony L, et al: Lactobacillus and bifidobacterium in irritable bowel syndrome: symptom responses and relationship to cytokine profiles. Gastroenterology 128: 541-551, 2005.
Passeron T, et al: Prebiotics and synbiotics: two promising approaches for the treatment of atopic dermatitis in children above 2 years. Allergy 61: 431-437, 2006.
Rastall RA: Bacteria in the gut: friends and foes and how to alter the balance. J Nutr 134: 2022S-2026S, 2004.
Ruatava S, et al: New therapeutic strategy for combating the increasing burden of allergic disease: Probiotics – a Nutrition, Allergy, Mucosal Immunology and Intestinal Microbiota (NAMI) Research Group report. J Allergy Clin Immunol 116: 31-37, 2005.
Rosenfeldt V, et al: Effect of probiotics on gastrointestinal symptoms and small intestinal permeability in children with atopic dermatitis. J Pediatr 145: 612-616, 2004.
Rosenfeldt V, et al: Effect of probiotic Lactobacillus strains in children with atopic dermatitis. J Allergy Clin Immunol 111: 389-395, 2003.
Saavedra JM, et al: Long-term consumption of infant formulas containing live probiotic bacteria: tolerance and safety. Am J Clin Nutr 79: 261-267, 2004.
Savino F, et al: Intestinal microflora in breastfed colicky and non-colicky infants. Acta Paediatr 93: 825-829, 2004.
Savino F, et al: Bacterial counts of intestinal Lactobacillus species in infants with colic. Pediatr Allergy Immunol 16: 72-75, 2005.
Sazawal S, et al: Efficacy of probiotics in prevention of acute diarrhoea: a meta-analysis of masked, randomized, placebo-controlled trials. Lancet Infect Dis 6: 374-382, 2006.
Schrezenmeir J, et al: Benefits of oral supplementation with and without synbiotics in young children with acute bacterial infections. Clin Pediatr (Phila) 43: 239-249, 2004.
Szajewska H, Ruszczynksi M, Radzikowski A: Probiotics in the prevention of antibiotic-associated diarrhea in children: a meta-analysis of randomized controlled trials. J Pediatr 149: 367-372, 2006.
Teitelbaum JE: Probiotics and the treatment of infectious diarrhea. Pediatr Infect Dis J 24: 267-268, 2005.
Vanderhoof JA, et al: Lactobacillus GG in the prevention of antibiotic-associated diarrhea in children. J Pediatr 135: 564-568, 1999.
Van Niel CW, et al: Lactobacillus therapy for acute infectious diarrhea in children: a meta-analysis. Pediatrics 109: 678-684, 2002.
Viljanen M, et al: Probiotics in the treatment of atopic eczema/dermatitis syndrome in infants: a double-blind placebo-controlled trial. Allergy 60: 494-500, 2005.
Weizman Z, et al: Effect of a probiotic infant formula on infections in child care centers: comparison of two probiotic agents. Pediatrics 115: 5-9, 2005.
Weston S, et al: Effects of probiotics on atopic dermatitis: a randomized controlled trial. Arch Dis Child 90: 892-897, 2005.
Young RJ, Huffman S: Probiotic use in children. J Pediatr Health Care 17: 277-283, 2003.