Our microbiome: The role of vital gut bacteria, diet, nutrition and obesity Prof Kevin Whelan Professor of Dietetics King s College London @ProfWhelan #BSG2017 Speaker Declarations This presenter has the following declarations of relationship with industry Research grants from: Almond Board of California; Clasado Biosciences; Nestle Consultancy for Danone Co-inventor of mobile app (Food Maeastro FODMAP app) 1
Hierarchy of scientific evidence Lots of clinical trials added together Clinical trial with a control group (intervention) Measure people over time (observational) Compare people with (case) and without (control) a characteristic (observational) Experience of 1 person (e.g. social media) Opinion of an expert (e.g. social media) 2
We know a lot more about our microbiome than we used to! Rajilic-Stojanov, FEMS Micro Rev 2014;38:996 1047 Each of us have a lot of gut bacteria! 2,550,000 2.5 million 38,000,000,000,000 38 trillion Sender et al, Plos Biol 2016; 14: e1002533 7,512,599,807 7.5 billion http://www.worldometers.info/world-population/ 3
Gut microbiome (bacteria in the gut) Stomach 10 3 bacteria per ml (= 1,000 per ml) e.g. Helicobacter pylori Small intestine 10 6 bacteria per ml (= 1,000,000 per ml) e.g. Lactobacilli, gram positive cocci Large intestine (Colon) 10 12 bacteria per g (= 1,000,000,000,000 per g) e.g. Bacteroides, clostridia, bifidobacteria, eubacteria, enterobacteria etc etc etc Our GI microbiota are the same but different 100% of humans have the same 18 bacteria in their gut 90% of humans have the same 57 bacteria in their gut 50% of humans have the same 75 bacteria in their gut Qin et al, Nature 2010; 464: 59-67 4
Microbiota: beneficial functions in health Flint et al, Nature Gastro 2012; 9: 577-589 Diet associated with different microbiome: Case-control study Burkina Faso Florence Italy De Filipo, Proc Nat Acd Sci 2010; 107: 14691-6 5
Lozupone et al, Nature 2012; 489: 220-230 Probiotics Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host (FAO/WHO, 2002) 6
Same probiotic has different impact on gut microbiome in different people All taking same probiotic. All have different amounts of it in their gut (some high, some low) After stopping taking the probiotic, it disappears from the gut Before probiotic During probiotic After probiotic Derrien & Veiga, Trends Micro 2017; 25: 100-112 Do probiotics impact on other bacteria in microbiome? Kristensen, Genome Med, 2016; 14: 82 7
Probiotics: many clinical trials in a range of gut disorders Hungin, Aliment Pharm Ther, 2013; 38: 864-886 Dietary fibre All non-digestible carbohydrates with degree of polymerisation of 3 plus lignin Scientific Advisory Committee on Nutrition, 2015 All compounds made up of 3 or more sugars linked in a chain that humans can t digest @ProfWhelan, 2017 Recommended intake (UK) 30 g/d Actual intake (UK) c. 18 g/d 8
Fibre can treat constipation Christodoulides, Alim Pharm Ther 2016; 44: 103-116 Fibre associated with reduced risk of colorectal cancer (SACN Report) Actual UK intakes UK recommended intake For every extra 7 g/d of fibre someone eats, 8% reduction in risk of colorectal cancer (RR 0.92, P=0.002) 9
Fibre has lots of other benefits: SACN report For every extra 7 g/d of fibre eaten: 9% reduction in cardiovascular disease (RR 0.91, P<0.001) 9% reduction in heart attacks (RR 0.91, P<0.001) 7% reduction in strokes (RR 0.93, P=0.002) 6% reduction in type 2 diabetes (RR 0.94, P=0.001) Prebiotics Non-digestible food components that selectively stimulate the growth and/or activity of one or a limited number of microbial genera, species or strains in the gut microbiota that confer health benefits to the host ILSI Expert Panel on Prebiotics Special type of fibre that help good bacteria grow in numbers or activity @ProfWhelan, 2017 10
Irritable bowel syndrome 5-15% of the UK population Significant impact on individuals, families and healthcare Prebiotic trial in IBS Silk et al, Alim Pharm Ther 2009; 29, 508 518 11
Fermentable Oligosaccharides (fructans) Disaccharides (lactose) Monosaccharides (fructose) And (α-galacto-oligosaccharides) Polyols (sorbitol, mannitol, xylitol) Fructose increases water in the small intestine Fructans increase gas in the colon (large intestine) Fructose after 1 hour Fructans after 4 hours Murray et al, Am J Gastro 2014; 109: 110-119 12
Low FODMAP diet advice: dietitian needed! Identifying suitable foods www.kcl.ac.uk/fodmaps www.foodmaestro.me/fodmap-app Low FODMAP diet AND... Probiotics in IBS Fermentable Oligosaccharides Disaccharides Monosaccharides And Polyols 13
Low FODMAP diet AND... Probiotics in IBS Staudacher et al, Gastro (in press) Inflammatory bowel disease (IBD) Crohn s disease Ulcerative colitis 14
Microbiota alterations precede disease Crohn s and their siblings have luminal microbiome with lower: F. prausnitzii Clostridia cluster IV Ruminococcus Roseburia Hedin et al, Gut, 2014; 63: 1578 1586. Manipulating the microbiome in IBD Microbiome that increase inflammation Microbiome that are anti-inflammatory 15
Manipulating the microbiome in IBD Microbiome that increase inflammation Microbiome that are anti-inflammatory Faecal microbiota transplant in ulcerative colitis 75 people with active ulcerative colitis 38 faecal enemas 37 water enemas Weekly enemas for 6 weeks Achieving remission after 6 weeks FMT group 24% Placebo group 5% (p=0.03) Moayyedi et al. Gastroenterology 2015; 149: 102-9 16
Obesity Obese (grade 2) 94% greater risk Obese (grade 1) 45% greater risk Overweight 7-18% greater risk BMI Mortality, Lancet, 2016; 388: 776-786 Obesity and the gut microbiome Diet Gut microbiota People with obesity have different microbiota Microbiota alter energy harvest in the gut and impact on inflammation Obesity Graham, Nutr Reviews, 2015; 73: 376-385 17
Probiotics and weight loss 0.59 kg (c 1 lb) more weight loss if taking a probiotic Zhang, Int J Food Sci Nutr, 2016; 67: 571 80 Summary The gut microbiome are numerically enormous and have a profound impact on our health and are also involved in many disorders (e.g. IBS, inflammatory bowel disease, obesity), but not the only cause! Some types of probiotics and some prebiotics can help some people with some disorders To keep your microbiome in good shape your diet should consist of the following (unless otherwise recommended by a doctor or dietitian): Diverse range of foods High in fibre High in fruit and vegetables High in pulses and beans 18
Futher reliable information on fibre, probiotics and healthy diet British Nutrition Foundation website www.nutrition.org.uk/ www.nutrition.org.uk/healthyliving/basics.html British Dietetic Association Food Fact Sheets www.bda.uk.com/foodfacts/home @ProfWhelan Further reliable information on fibre, probiotics and healthy diet @ProfWhelan Clinical guide to probiotic products http://usprobioticguide.com/ 19
Acknowledgements Dr James Lindsay Dr Charlotte Hedin Dr Andy Stagg Dr Heidi Staudacher Dr Miranda Lomer Dr Peter Irving @ProfWhelan 20