Shane is one of Australia’s leading professional nutritionists with over 15 years consulting experience. He is a member of the Dietitians Association of Australia and is an Accredited Practising Dietitian.

Professionally, Shane has a longstanding academic interest in dietary fibre, resistant starch and the benefits of plant based eating and is a regular speaker at health professional conferences, such as GPCE in Sydney.

In addition to his consulting activities, Shane has built an extensive media career with weekly nutrition programs on radio 2UE and Great Southern and has authored numerous nutrition and health articles for popular magazines. In addition, communication agencies regularly seek Shane’s advice when creating nutrition campaigns for their clients.

Shane holds a Bachelor of Science Degree, Post Graduate Diploma in Nutrition and Dietetics, Graduate Certificate in Marketing and a Master of Business Administration Degree from Macquarie University.

The Author

Shane LandonAccredited Nutritionist and Accredited Practising Dietitian

Resistant Starch ReviewShane Landon Accredited Nutritionist and Accredited Practising Dietitian, Sydney, Australia

The recent inclusion of resistant starch in the Australian Government’s revised dietary fibre recommendations1 acknowledges resistant starch as a key dietary component vital for good health. The challenge remains for health professionals and the food industry to specifically improve resistant starch consumption, while increasing total fibre intake.

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Despite the fact that increasing dietary fibre has been linked to lower rates of obesity, cardiovascular disease, diabetes and certain cancers1, boosting Australians’ fibre intake remains a challenge. One barrier to increased fibre consumption may be the perception that dietary fibre – both as a nutrition issue and as a field of science - is not “cutting edge.”

However, the scientific emergence of resistant starch and now its recognition by the National Health and Medical Research Council (NHMRC), indicates that the field of dietary fibre is both dynamic and developing. Indeed, the research supporting the health benefits of resistant starch is compelling with the NHMRC’s Nutrient Reference Values report indicating that in comparison to traditional fibre:

“…resistant starch may be as significant if not more so for many health conditions.” National Health and Medical Research Council, Nutrient Reference Values pg 45.

First identified in 19822, resistant starch is included in the dietary fibre definition used by Food Standards Australia New Zealand (FSANZ) and is widely acknowledged within the scientific community as having valuable health benefits. Leading Australian scientists including Dr David Topping and Professor Graeme Young have played a pioneering role in advancing our understanding of the importance of resistant starch – particularly in relation to bowel health.

In their 2001 review paper3, Dr Topping and co-author Dr Peter Clifton, suggested that resistant starch was as significant, if not more so, than non-starch polysaccharides in regard to colorectal cancer prevention – with the preventative effect likely to be mediated via the short chain fatty acid, butyrate.

However, the proposition that other dietary components (like resistant starch) may be more significant than traditional NSP fibre in relation to colon cancer prevention was first mooted in 1994. An international comparison conducted by a team of UK researchers showed a stronger correlation between reduced colon cancer risk and starch intake (and thus resistant starch) than with dietary fibre (ie NSP)4.

Incidence of bowel cancer per 100,000 (adjusted for age)

250

05

100

10 15

Star

ch in

take (

gram

s/day

)

50

China

20 25 30

150

200

300

350

400

India

Finland

Japan

Britian

Australia

USA

Source: Cassidy et al (1994) Br J Cancer 69:119-125

Beyond these and many other bowel-health related findings, resistant starch exerts a range of metabolic effects that may also confer health advantage – including energy management and lipid oxidation5 as well as the capacity for resistant starch to play a valuable role in oral re-hydration therapy6.

In addition, there are exciting new developments associated with the fermentation of resistant starch that may have important implications for one of Australia’s major public health issues – overweight and obesity.

The decision by the NHMRC to include resistant starch as part of its dietary fibre recommendations reinforces the need for health professionals to appreciate the science supporting resistant starch’s role in health, and to readily identify food sources for their patients.

Resistant starch explainedA decade after the term was first used, EURESTA provided a physiological definition for resistant starch:

“Total amount of starch, and the products of starch degradation that resists digestion in the small intestine of healthy people 7.”Starches that resist small intestinal breakdown are fermented by the resident bacteria in the large intestine, producing a variety of end products, the most significant of which is the short chain fatty acids (SCFA)8.

These consist primarily of butyrate, propionate and acetate and are the preferred energy source for the colonocytes (cells lining the colon). Other benefits of SCFA’s include:

• Increased colonic blood flow;

• Beneficially lowers pH in the lumen which may aid mineral bioavailability and reduces the growth of pathogenic bacteria;

• Helps prevent abnormal colonic cell development3.

To support EURESTA’s physiological definition of resistant starch and take into account the physical characteristics of the various resistant starches which exist, four sub-types have been developed:

• RS1 The starch is physically inaccessible to digestion due to intact cell walls, eg grains. • RS2 Native starch granules protected from digestion by the structure of the starch granule.• RS3 Retrograded starch - eg cooked then cooled potato, rice or pasta. RS3 forms as it cools.• RS4 Chemicallymodifiedstarches–donotoccurnaturally but are created to be resistant to digestion.

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Considerable attention has focused on a particular form of RS2 from high amylose maize starch (Hi-maize®) because it retains its resistance during food processing5. This facilitates its use in everyday consumer food products and makes possible many of the human feeding trials conducted to assess the health effects of resistant starch.

ThenewdietaryfibrerecommendationsforAustralia and New ZealandThe recent release of the Nutrient Reference Values (NRV) by the NHMRC1 is having a dramatic impact on Australia’s nutritional landscape. The comprehensive review, chaired by Dr. Katrine Baghurst, covered the major macronutrients including dietary fibre, vitamins, minerals and trace elements.

In a first for any government authority, the NHMRC’s recommendations specifically include a resistant starch component in the fibre intake figures – reflecting its considerable contribution to human health.

“We considered the scientific evidence showing a positive impact of resistant starch on digestive health convincing and warranted inclusion in the new fibre intake recommendations.”Dr. Katrine Baghurst, Chair, Nutrient Reference Values Working Party.

The fibre intake recommendations issued by the NHMRC are called “Adequate Intake” amounts and represent the average amount of dietary fibre needed for general health.

Table1:AdequateIntakerecommendationsfordietaryfibre

Males Adequate Intake (g/day)

Females Adequate Intake (g/day)

0-6 months no AI set 0-6 months no AI set7-12 months no AI set 7-12 months no AI set1-3 years 14 1-3 years 144-8 years 18 4-8 years 189-13 years 24 9-13 years 2014-18 years 28 14-18 years 2219-30 years 30 19-30 years 2531-50 years 30 31-50 years 2551-70 years 30 51-70 years 2571+ years 30 71+ years 25

Pregnancy14-18 years 25

Source: NHMRC 2006 19-30 years 2831-50 years 28Lactation14-18 years 2719-30 years 3031-50 years 30

Dietaryfibre-reducingtheriskofchronicdiseaseImportantly, the NHMRC’s Nutrient Reference Values report also considered the capacity for certain nutrients, when consumed at higher levels, to actively reduce disease risk. Dietary fibre, with its links to lower rates of obesity, cardiovascular disease, diabetes and certain cancers, is considered to have this ability.

Contained in the section Optimising Diets for Lowering Chronic Disease Risk, the NHMRC goes beyond the Adequate Intake figures for fibre and aims to provide recommendations to actually reduce disease risk – termed Suggested Dietary Targets (SDT).

SuggestedDietaryTargetsfordietaryfibre1:Men–38grams/dayWomen–28grams/day

These targets present health professionals with two considerable challenges:

1. To educate the public about the benefits of much higher fibre intakes;

2. To significantly modify individual dietary patterns to achieve these higher intakes in an acceptable way for clients/patients.

The NHMRC’s acknowledgement of fibre’s disease fighting potential is an important step in replacing the simplistic notion that fibre’s role is solely that of “maintaining regularity”.

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How much resistant starch do we consume?A recent estimate of resistant starch intakes for Australians derived from the 1995 National Nutrition Survey, suggested the range of intake to be from 3.4grams/day to a maximum of 9.4grams/day, with adult men consuming more resistant starch (10.7 grams/day) than women (8.2 grams/day)9.

Table 2: Resistant starch intakes (mean ± SEM) by age and gender (g/day) based on upper (RS max) and lower (RS min) estimates of RS in foods

RS g/day Male FemaleAge Group(years)

Mean ± SEM

(RS Max)

Mean ± SEM

(RS Min)

Mean ± SEM

(RS Max)

Mean ± SEM

(RS Min)2-3 6.2 ± 0.4 2.4 ± 0.1 5.5 ± 0.3 2.1 ± 0.14-7 7.3 ± 0.3 2.9 ± 0.1 6.1 ± 0.2 2.5 ± 0.18-11 8.2 ± 0.3 3.1 ± 0.1 7.1 ± 0.2 2.7 ± 0.112-15 10.1 ± 0.4 3.7 ± 0.1 7.3 ± 0.3 2.8 ± 0.116-18 11.6 ± 0.7 3.9 ± 0.2 7.4 ± 0.4 2.7 ± 0.119-24 11.4 ± 0.4 4.0 ± 0.1 8.2 ± 0.3 2.9 ± 0.125-44 11.1 ± 0.2 4.0 ± 0.1 8.3 ± 0.1 3.1 ± 0.045-64 10.7 ± 0.2 3.8 ± 0.1 8.2 ± 0.1 3.0 ± 0.165+ 9.5 ± 0.2 3.3 ± 0.1 7.8 ± 0.2 2.8 ± 0.1Adults 19+ 10.7 ± 0.11 3.8 ± 0.04 8.2 ± 0.08 3.0 ± 0.03

How much resistant starch do we need?The Commonwealth Scientific and Industrial Research Organisation (CSIRO), has recommended that intakes of resistant starch should be around 20g a day, which is almost four times greater than a typical western diet currently provides10.

Studies11-15 conducted on a particular type of RS2 (Hi-maize®) indicate that in order to achieve a positive impact on one or more of the accepted parameters of digestive health, 17g/day or more is required in the diet.

As the suggested intakes for resistant starch are significantly higher than current consumption, there is considerable scope to increase resistant starch consumption across the population.

Australia - a resistant starch pioneer!Australian scientists and food manufacturers have been at the forefront of understanding the role of resistant starch inhealthaswellasfindingeffectiveusesforresistantstarch in everyday foods.Infact,thefirstcommerciallyavailableresistantstarchfood ingredient was developed in Australia and introduced intothefoodsupplyintheformoffibreenrichedwhitebread (Wonder White) in 1994. The ingredient in question, Hi-maize, is naturally derived from non-GM maize and can be added to foods without changing the taste or texture. The year after its launch, Hi-maize was awarded the 1995 AIFST Food Industry Innovation Award16 and Wonder White continues to be one of the major sources of resistant starch in the Australian diet9.

Resistant starch and colonic healthResistant starch mediates its impact via bacterial fermentation in the large bowel leading to a range of positive effects including a reduction in stool pH, a mild laxative effect and the production of SCFA’s17.

Short Chain Fatty AcidsConsiderable interest has focused on the benefits of the short chain fatty acids – and in particular, butyrate. In addition to it being a favoured energy source of the colon cells18, butyrate has also been shown to facilitate other important physiological changes including:

• The capacity to reverse neoplastic changes in vitro19,

• Nutritive effects on the colonic epithelium20,

• Inducing apoptosis (programmed cell death) of damaged cells20.

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Importantly, resistant starch is one of the best substrates for the production of butyrate – producing levels twice that of wheat fibre and four times that of pectin (see table 3) 21.

Table 3: Patterns of Short Chain Fatty Acids for various substrates as a percentage of total acid production

Substrate Acetate Propionate ButyrateResistant starch

41 21 38

Oat bran 57 21 23Wheat bran 57 15 19Cellulose 61 20 19Guar gum 59 26 11Pectin 75 14 9

Prebiotic propertiesPrebiotics are defined as non-digestible carbohydrate substrates that stimulate the growth and/or activity of beneficial bacteria in the colon to improve the health of the host22.

Interest in the role of prebiotics is a more recent phenomenon than that of probiotics (the supply of exogenous bacteria - usually in the form of lactic acid species) for which early research dates back as far as 190723.

However, a consistent issue relating to the effectiveness of probiotic therapies concerns the ability for the probiotic bacteria to survive the perilous journey through the upper gastrointestinal tract and then, to effectively colonise once they arrive23.

Prebiotics can assist in promoting bacterial colonisation and may well be able to act as enhancers of probiotic bacteria23.

Resistant starches have prebiotic properties and may provide protection to beneficial Bifidobacteria in vivo as they travel through the upper gastrointestinal tract24 – the so-called “synbiotic effect”.

Although there is still much investigation required to develop our understanding in this field, the potential to capture the benefits of prebiotics and probiotics in relation to measurable health outcomes is very exciting.

SynbioticsAn emerging dimension in digestive health and specifically colorectal cancer research targets the synergistic interaction between prebiotics and particular strains of probiotic bacteria25.

Preliminary animal research conducted by Dr Richard Le Leu, has shown that when resistant starch (Hi-maize®) and a particular healthy probiotic (bacteria) are given, they work together to increase the elimination of damaged colon cells25.

“Research is starting to show that resistant starch intake can aid in the removal of DNA-damaged cells in the colon.”Dr Richard Le Leu - Research Fellow, School of Medicine, Flinders University.

Dr Le Leu has now expanded his research program to determine if this synbiotic effect also occurs in humans.

Oral re-hydration therapyIn many developing countries, diarrhoea is a major cause of mortality. The main treatment is oral rehydration therapy, the administration of a controlled glucose-based solution. This simple but effective treatment has saved many lives, and has been hailed as one of the great medical advances of the twentieth century. However, while oral rehydration solution corrects dehydration, it does not reduce the diarrhoea itself6.

Research has now shown that the addition of resistant starch to oral rehydration solutions reduces fecal fluid loss and shortens the duration of diarrhoea in adolescents and adults with cholera6.

This exciting finding has generated considerable scientific interest and created the potential to develop a new oral rehydration solution that both rehydrates and reduces diarrhoea.

Fibre, resistant starch and bowel cancer in AfricansA new twist to an old story!In what has become nutritional folklore, Dennis Burkitt firsthypothesizedthatcoloncancermaybecorrelatedtodietaryfibre(ieNSP)intakesasaresultofhisobservational studies of native African populations26.However, despite the adoption of “Westernised diets” bynativeAfricansresultinginmuchlowerdietaryfibre(NSP) intakes than most Western populations, there has been no increase in colon cancer in the urban black African population27,28. In fact, native Africans continue to have colon cancer rates 10 times lower than their white counterparts in the same region29.This surprising result may be due to the regular and significantconsumptionofcoldmaizeporridge.Maizeporridge is a dietary staple among black Africans and when consumed cold, as it often is, the porridge is rich in resistant starch (an RS3 retrograded form). This leads to significantlyhigherlevelsofshortchainfattyacids30.The higher levels of resistant starch fermentation are considered to play a role in the protection against colorectal cancer observed in native Africans30.

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Focus on fermentationColon CancerThere is growing recognition of the important connection between diet and bacterial metabolism in the colon and specifically how the interaction can impact diseases like colon cancer29.

In fact, the human colon is one of the most densely populated natural habitats known to science with the human body containing an order of magnitude more prokaryotic cells than it does mammalian ones29. As such;

The bacterial flora in the gastrointestinal tract should be considered “an organ within an organ” exerting considerable metabolic capability.

Research with dietary components, like resistant starch, supports a direct link between diet, colonic bacteria and colon cancer, with recent animal studies indicating high resistant starch diets may prevent colon carcinogenesis29.

SatietyRecent breakthrough research has linked the fermentation of resistant starch with increased levels of gut hormones (PYY and GLP-1) that play a role in satiety and potentially, long-term energy balance31.

While the research is still in its early stages, the link between the products of resistant starch fermentation and gene expression for hormones shown to reduce energy intake is very exciting. Indeed, with his most recent findings, the principal investigator, Dr. Michael Keenan suggested:

“We believe the fermentation of resistant starch may be an effective, natural approach to the treatment of obesity.”

Metabolic impacts of resistant starchA number of studies have been conducted to investigate the metabolic significance of resistant starch consumption including postprandial glucose and insulin response as well as macronutrient oxidation.

Glycaemic ImpactThere is considerable consumer and media interest in the way in which carbohydrates release glucose into the bloodstream32 with attenuation of postprandial glucose and insulin levels likely to confer considerable health benefit compared to carbohydrates that are more rapidly digested.

Although it is difficult to compare the various studies undertaken to investigate glucose and insulin response, the data supports a role for resistant starch intake in reducing postprandial glucose and/or insulin response33.

Indeed, a number of human studies have demonstrated the capacity for Hi-maize® resistant starch to elicit a positive impact on both postprandial glucose levels14,34-38 as well as insulin response14, 34-36,39,40.

Most recently, a human trial with maize-based resistant starch incorporated into test beverages showed effective reductions in the relative glycaemic response without any change in palatability41.

While exact mechanisms are to be revealed, improved insulin sensitivity is considered one means whereby the reductions are facilitated33. In addition, the incorporation of a resistant starch ingredient reduces the digestible carbohydrate fraction - translating to a lowered glycaemic response – making such an ingredient an attractive option5.

Dietaryfibreandbodyweight–Theforgottenconnection?The global burden of obesity continues to increase both in terms of ill-health as well as direct economic cost to the community. Diet and lifestyle have long been recognised asmodifiableriskfactorsforweightgain.However,inthesearchforanswers,theroleofahighfibredietintheprevention of weight gain is often overlooked.In its global report, “Diet, Nutrition and the Prevention of Chronic Diseases”, the World Health Organisation identifiedahighintakeoffibreastheonlydietarycomponent with the “convincing evidence” required to protect against weight gain and obesity43.Itappearsthatdietaryfibre’sabilitytoincreasesatietyandtherefore decrease subsequent hunger, along with altering the secretion of hormones related to food digestion, are likely mechanisms44. Indeed,themostrecentfindingfromanimalstudiesthatresistantstarchfermentationspecificallyincreasesthelevels of satiety hormones31 provides important support for fibre’sabilitytopreventweightgainasdoesthecapacityfor resistant starch to increase fat oxidation. Health professionals often limit fibre’s role to one of “maintaining regularity” when independent scientific reports from the Australia’s NHMRC and the World Health Organisation reveal its role in chronic disease prevention is central.

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Resistant Starch and Lipid OxidationRecent research has shown resistant starch has the capacity to increase fat oxidation42.

Trials conducted in the US have shown that the consumption of a meal containing 5 percent resistant starch led to an increase in fat oxidation of 23 percent, and this increase is sustained throughout the day, even if only one meal contained resistant starch42.

Although further research is required to support these findings and to elucidate possible mechanisms, it appears that the inclusion of resistant starch changed the order in which the body oxidized the available macronutrients, preferentially oxidizing fat42.

Taken in combination with recent animal research linking resistant starch fermentation with increased levels of satiety hormones and the World Health Organisation research43 supporting the ability of dietary fibre to protect against weight gain, the potential for high fibre eating patterns (including resistant starches) to address the growing burden of obesity is very real44.

Sources of resistant starchResistant starch can be found in small amounts in lentils, baked beans and some cereals. It can also be found in cooked then cooled potato, rice and pasta (RS3 forms of resistant starch).

However one of the richest natural sources of resistant starch is derived from high amylose maize called Hi-maize. Rich in resistant starch and fibre, Hi-maize has the essential benefits described in this paper for resistant starch and because of its fine texture can be added to a range of foods without changing their taste.

Commercial food products with Hi-maize®

Wonder White Breads and Muffins

Vogels Breakfast Cereals - Ultra Bran Soy & Linseed - Vitapro - Soytana

Uncle Toby’s Fruit Bars - Chewy Muesli Bars - Yoghurt Topps - Fruit Twist

Healthwise Cereals - For Improved Bowel and Digestive System - For Women 40+ - For Heart Health

Freedom Foods Cookies Pancake Shake Instant Custard Mix Corn Fritter Mix Spaghetti Chocolate Chip Slice Strawberry Slice

Sanitarium Up & Go Liquid Breakfasts Up & Go Energize drink Light & Tasty Breakfast Shake

EntraLive Maximal Flavoured Probiotic Drink Mix Concentrate

Nabisco High Fibre Premium Crispbread

Lowan Whole FoodsSoy Flakes

Lean Cuisine Pizzas Paradise Lites White Crispbread 97% fat free

Kellogg’s K-time Bars Heinz Little Kids Soft Fruit Bars

Commercial food products with Hi-maize®

Aussie Bodies Protein FX EnergyBars (Caramel Fudge)

Basco Gluten Free Wheat Free Pancake Mix

Select Foods Hi-maize Powder - available in health shops (1300 552 804 for supply)Current as at June 2007 - check with manufacturers for further details.

DiscussionThe capacity for resistant starch to improve colonic health is now established to the point where the NHMRC have specifically included resistant starch in their dietary fibre advice.

Resistant starch has the ability to enhance the fibre content of everyday staple foods, like bread and cereals, providing the public with another means of achieving their daily fibre requirement – be it for general good health or to reduce chronic disease risk.

From a research perspective, the emerging fields of weight control, insulin sensitivity and diarrhoea management offer exciting new dimensions for resistant starch.

The colonic fermentation of resistant starch also requires continued investigation to fully unlock its significance, in terms of the health of the lumen itself as well as the various metabolic sequences associated with the process, such as satiety.

For the most comprehensive single source of resistant starch information, visit www.resistantstarch.com.

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References1. National Health and Medical Research Council (2006) “Nutrient Reference Values for Australia and New Zealand including Recommended Dietary Intakes”.2. Englyst H, et al (1982), Analyst 107:307-18.3. Topping D, Clifton P. (2001) “Short chain fatty acids and human colonic function – roles of resistant starch and non starch polysaccharides” Physiol. Reviews 81:1031-64.4. Cassidy A et al (1994) “Starch intake and colorectal cancer risk: an international comparison. British Journal of Cancer 69:937-42.5. Nugent AP, (2005) “Health Properties of Resistant Starch”, British Nutrition Foundation, Nutrition Bulletin Vol 30 No 1 27-54.6. Ramakrishna B.S, et al (2000) “Amylase-Resistant Starch plus Oral Re-hydration Solution for Cholera” New England Journal of Medicine Vol. 342, No5, 308-313.7. Asp NG (1992) Resistant starch – proceedings from the second plenary meeting of EURESTA: European FLAIR Concerted Action, 11 on physiological implications of the consumption of resistant starch in man. Preface. European J Clin. Nutr. 46: S1.8. Englyst H, et al (1996), “Measurement of resistant starch in vitro and in vivo. British Journal of Nutrition 75:749-55. 9. Roberts J et al (2004) Resistant starch in the Australian Diet Nutr Diet 61:98-104. 10. Baghurst PA, Baghurst KI, Record SJ. (1996) Dietary fibre, non-starch polysaccharides and resistant starch – a review. Food Aust;48(Suppl):S3–S35.11. Birkett, A.; Muir, J.; Phillips, J.; Jones, G.; O’Dea, K. (1996). Resistant starch lowers fecal concentrations of ammonia and phenols in humans. Am J Clin Nutr 63(5):766-772.12. Muir, J.G.; Lu, Z.X.; Young, G.P.; Cameron-Smith, D.; Collier, G.R.; O’Dea, K. (1995). Resistant starch in the diet increases breath hydrogen and serum acetate in human subjects. Am J Clin Nutr 61(4):792-799.13. Muir, J.G.; Yeow, E.G.; Keogh, J.; Pizzey, C.; Bird, A.R.; Sharpe, K.; O’Dea, K.; Macrae, F.A. (2004). Combining wheat bran with resistant starch has more beneficial effects on fecal indexes than does wheat bran alone. Am J Clin Nutr 79(6):1020-1028.14. Noakes, M.; Clifton, P.M.; Nestel, P.J.; Le Leu, R.; McIntosh, G. (1996). Effect of high-amylose starch and oat bran on metabolic variables and bowel function in subjects with hypertriglyceridemia. Am J Clin Nutr 64(6):944-951. 15. Phillips, J.; Muir, J.G.; Birkett, A.; Lu, Z.X.; Jones, G.P.; O’Dea, K.; Young, G.P. (1995). Effect of resistant starch on fecal bulk and fermentation-dependent events in humans. Am J Clin Nutr 62(1):121-130. 16. Brown IL et al (1995) Hi-maize: new directions in starch technology Food Australia 47 (6). 17. Young GP and Le Leu RK (2004) “Resistant starch and colorectal neoplasia” Journal of the Association of Official Analytical Chemists International 87(3):775-86.18. Schwiertz A et al (2002) “Influence of resistant starch on the SCFA production and cell counts of butyrate-producing Eubacterium spp. in the human intestine.” Journal of Applied Microbiology 93 (1):157-62.19. Ferguson LR et al (2000) “Comparative effects of three resistant starch preparations on transit time and short-chain fatty acid production in rats”. Nutrition and Cancer 36 (2):230-7.20. Mentschel J & Claus R (2003) “Increased butyrate formation in the piog colon by feeding raw potato starch leads to a reduction of colonocyte apoptosis and a shift to stem cell compartment”. Metabolism 52(11):1400-5.21. Champ MJ (2004) Adapted from “Physiological effects of resistant starch and in vivo measurements” Journal of the Association of Official Analytical Chemists International 87(3):749-55.22. Gibson GR & Roberfroid MB, (1995) “Dietary modulation of the human microbiota: introducing the subject of prebiotics” Journal of Nutrition 125:1401-12. 23. Topping D, et al (2003) Resistant starch as a prebiotic and synbiotic: state of the art. Proceedings of the Nutrition Society 62,171-176. 24. Wang X et al, (1999) “In vitro utilization of amylopectin and high-amylose maize (Amylomaize) starch granules by human colonic bacteria” Journal of Applied Microbiology 87:631-9. 25. Le Leu RK et al, (2005) “A Synbiotic Combination of Resistant Starch and Bifidobacterium lactis Facilitates Apoptotic Deletion of Carcinogen-Damaged Cells in Rat Colon” J. Nutr. 135:996-1001. 26. Burkitt DP. (1971) Epidemiology of cancer of the colon and the rectum. Cancer; 28:3-13. 27. O’Keefe SJD, Ndaba N, Woodward A. (1985) Relationship between nutritional status, dietary intake patterns and plasma lipoprotein concentrations in rural black South Africans. Hum Nutr Clin Nutr; 39:335-41.28. Segal I. (2002) Physiological small bowel malabsorption of carbohydrates protects against largebowel diseases in Africans. J Gastroenterol Hepatol; 17:249-52.29. Ridlon JM & Hylemon PB (2006) A Potential Role for Resistant Starch Fermentation in Modulating Colonic Bacterial Metabolism and Colon Cancer Risk. Cancer Biology & Therapy vol 5:issue 3, 273-4.30. Ahmed R et al (2000) Fermentation of dietary starch in humans. Am J Gastro, vol95 (4) 1017-1020.31. Keenan MJ, et al (2006) Effects of resistant starch, a non-digestible fermentable fiber, on reducing body fat. Obesity Vol. 14 No 9 1523-34. 32. Landon S (2005) “Modern diets converging: move to low GI/GR diets” Nutrition and Food Science 35 (5): 320-3.33. Higgins J (2004) “Resistant starch: metabolic effects and potential health benefits” Journal of the Association of Official Analytical Chemists International 87(3):761-8.34. Behall, K.M.; Hallfrisch, J. (2002). Plasma glucose and insulin reduction after consumption of breads varying in amylose content. Eur J Clin Nutr 56(9):913 920.35. Granfeldt, Y.; Drews, A.; Björck, I. (1995). Arepas made from high amylose corn flour produce favorably low glucose and insulin responses in healthy humans. J Nutr 125(3):459-465.36. Muir, J.; Lu, Z.; Collier, G.; O’Dea, K. (1994) [Unpublished]. The Acute Effects of High Resistant Starch Bread (Made from Hi-maize – A High Amylose Maize Starch) on Glucose and Insulin Responses in Non-diabetics. Deakin University, Faculty of Health and Behavioural Sciences, Deakin Institute of Human Nutrition; Victoria, Australia. Research Report to Quality Bakers Australia Limited.37. Muir, J.; O’Dea, K. (1992). Measurement of resistant starch: factors affecting the amount of starch escaping digestion in vitro. Am J Clin Nutr 56(1):123-127. [abstract only]38. Muir, J.; O’Dea, K. (1993). Validation of an in vitro assay for predicting the amount of starch that escapes digestion in the small inestin of humans. Am J Clin Nutr 57(4):540-546 [Abstract only].39. Glycaemic Index Testing, Inc. (2004) [Confidential]. Effects of Two Types of Resistant Starch on Plasma Glucose and Insulin Responses in Normal Subjects. Protocol: GIT-0314 (Final Report). Prepared by Glycaemic Index Testing, Inc.; Toronto for National Starch and Chemical Company,.July 27, 2004.40. Hoebler, C.; Karinthi, A.; Chiron, H.; Champ, M.; Barry, J.L. (1999). Bioavailability of starch in bread rich in amylose: Metabolic responses in healthy subjects and starch structure. Eur J Clin Nutr 53(5):360-366. 41. Kendall, CWC et al (2007) “Effect of novel maize-based dietary fibers on postprandial glycemia”. The FASEB Journal 21:368.3.42. Higgins J (2004) “Resistant starch consumption promotes lipid oxidation” Journal of Nutrition & Metabolism, 1:8.43. World Health Organisation, Joint WHO/FAO Expert Consultation (2003) “Diet, Nutrition and the Prevention of Chronic Diseases” WHO Technical Report Series 916.44. Slavin, JL (2005) “Dietary fiber and body weight.” Nutrition (3):411-8.

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Hi-maize and National Starch Food Innovation are trademarks of National Starch and Chemical Pty Ltd.

The information contained in this document was developed based on a review of published clinical studies performed to evaluate the benefits of resistant starch. Nothing contained in this document is intended to be relied upon by others in evaluating compliance with laws including, but not limited to, labelling laws with regard to any claims made for any product in which resistant starch is an ingredient. Any claims made in a label of a product are the responsibility of the manufacturer and seller of that product.

June 2007

For Health Professional Use

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Contacts

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