THE LOW-FODMAP DIET: AN OVERVIEW OF ITS DEVELOPMENT AND APPLICATIONS Diets involving the restriction of fermentable carbohydrates in order to provide relief from the symptoms of bloating, pain and other gastric discomfort, have been emerging for a number of years. In particular, a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (low-FODMAP) diet has increased in popularity. There has been considerable interest in the low-FODMAP diet and its applications in IBS and other conditions since its conception in 2005 and it has been recommended as a second-line intervention for IBS by the BDA since 2013, for relief of symptoms of bloating, pain and diarrhoea.1,2 IBS is thought to affect between 7-10% of people worldwide3 and over 80% of those with IBS report a link with food.4 Therefore, there is a continued interest in a diet which will help in some way to alleviate these symptoms, however much they may vary between individuals. WHY WAS IT DEVELOPED?
For some time, it was recognised that though certain foods may be more ‘gas producing’ than others, ie, brassicas, dairy, beans, pulses and legumes, there had never been a recognised group classification of these foods and their components. This meant that potential dietary interventions were difficult to assess and there was no set guidance for identifying individual tolerance levels. The collective term ‘FODMAPs’ was coined in 2004 by a team of researchers at Monash University in Australia, who were keen to create a dietary intervention that included all of the problematic short-chain carbohydrates that had previously been identified. Those which were included had been recognised to cause symptoms due to malabsorption, maldigestion,
fermentation and osmotic load. Whereas previously, much research had focused on eliminating only one or two of these FODMAPs, the research team’s theory was that by removing all the FODMAPs – and carrying out a phased, carefully monitored reintroduction – dietary triggers and individual tolerance levels could be better assessed.5 The team then began to have their efforts recognised internationally through the development of further studies, initially through a hypothesis around the pathogenesis of Crohn’s disease.6 Overall, the team hypothesised that dietary restriction of these short-chain carbohydrates would reduce luminal distension (through reducing water/gas retention) and potentially bring relief to individuals with IBS who report visceral hypersensitivity. A small observational study showed improvement of symptoms following restriction of fructose.7 An exacerbation of symptoms with the reintroduction of fructose and fructan was then noted in a blinded controlled trial that re-challenged those who had previously reported improvement following restriction of fructose.8 This continued development included teaming up with international researchers in New Zealand and in the UK. Research began into the development of assessment tools, detailed food analysis, including cutoffs for high/low FODMAPs and assessment of the diet’s efficacy in other conditions.5
NUTRITION MANAGEMENT
Jessica English RD Self-employed Freelance Dietitian, founder of Level Up Nutrition Jess runs Level Up Nutrition, working with individuals on a one-to-one basis in Brighton and virtually UK-wide. She has a special interest in health communications and global public health nutrition. www.levelup nutrition.co.uk
REFERENCES Please visit the Subscriber zone at NHDmag.com
www.NHDmag.com April 2019 - Issue 143
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