Resistant Starch Intake Research Articles

Resistant starch promotes equol production and inhibits tibial bone loss in ovariectomized mice treated with daidzein

Daidzein is metabolized to equol in the gastrointestinal tract by gut microflora. Equol has greater estrogenic activity than genistein and daidzein, with its production shown to be promoted by dietary fiber. It is known that resistant starch (RS) is not absorbed in the proximal intestine and acts as dietary fiber in the colon. In this study, we investigated the combined effects of daidzein and RS intake on equol production, bone mineral density, and intestinal microflora in ovariectomized (OVX) mice. Female mice of the ddY strain, aged 8 weeks, were either sham operated (n = 6) or OVX. The OVX mice were randomly divided into 5 groups: OVX control (n = 6), OVX fed 0.1% daidzein-supplemented diet (OVX + Dz, n = 8), OVX fed 0.1% daidzein- and 12% RS-supplemented diet (OVX + Dz + RS, n = 8), OVX fed 12% RS-supplemented diet (OVX + RS, n = 8), and OVX who received daily subcutaneous administration of 17 β-estradiol (n = 6). After 6 weeks, urinary equol concentration was significantly higher in the OVX + Dz + RS group than in the OVX + Dz group. The bone mineral density of the whole tibia was higher in the OVX + Dz +RS group compared with the OVX + Dz group. The occupation ratios of Bifidobacterium spp in the cecal microflora in groups fed RS were significantly higher than those in the other groups. The present study demonstrated that RS may increase the bioavailability of daidzein.

Starch Intake and Health-physiological effects of resistant starch-

Starch Intake and Health-physiological effects of resistant starch-

Resistant starch, large bowel fermentation and a broader perspective of prebiotics and probiotics

The metabolic end products of the large bowel microbiota contribute significantly to human health. After weaning to solid foods, some of the most important of these are the short chain fatty acids (SCFA) produced by the fermentation of undigested dietary components and endogenous secretions. The main SCFA are acetate, propionate and butyrate which have numerous documented effects promoting large bowel function. Of the major acids, butyrate seems especially important. It is a major metabolic fuel for colonocytes and promotes a normal phenotype in these cells, potentially lowering the risk of diseases such as colo-rectal cancer. Imbalances in the microbiota are thought to predispose to large bowel dysfunction and probiotics are being developed to correct this. However, most commercial products contain bacteria (lactobacilli and bifidobacteria) which are dominant species in milk-fed infants but have limited roles in adults. Prebiosis is defined usually by the specific stimulation of these bacteria. However, the end products of most probiotics do not include butyrate or propionate which raises questions about their effectiveness in promoting bowel health in adults. Resistant starch (RS) is a dietary fibre component and its fermentation generally favours butyrate production. Dietary RS intakes and faecal butyrate levels are high in populations at low risk of diet-related large bowel diseases. Conversely, RS intakes and faecal butyrate levels are very low in high risk groups. This raises the possibility that greater RS consumption could be of health benefit. RS is not regarded widely as a prebiotic but (according to the accepted definition) most forms show the requisite features in stimulating specific bacteria, giving raised total SCFA and butyrate levels and a consequent benefit to the host. Current efforts to improve public health through increasing RS consumption could be facilitated by greater recognition of its prebiotic role.

Hypolipidaemic effect of maize starch with different amylose content in ovariectomized rats depends on intake amount of resistant starch

The effect of amylose content on digestibility of starch in the small intestine and on the concentration of plasma lipid were studied in ileorectostomized rats and in ovariectomized rats, respectively. Seven kinds of starch with different amylose content (0, 27, 54, 62, 76, 79, 86 %) were used as test starch, which contained 0.4, 5.6, 37.1, 40.2, 45.6, 36.9 and 36.1 % resistant starch (RS), respectively. Rats were fed one of test diets containing 30 % test starch with different amylose content for 14 d in ileorectostomized and for 21 d in ovariectomized rats. Food intake was not significantly different among the groups. In ileorectostomized rats, the small intestinal starch digestibility decreased with increasing intakes of amylose and RS. In ovariectomized rats, body weight gain was lower on the higher amylose maize starch diets. The concentrations of plasma TAG and cholesterol decreased with increasing intake of RS. The concentrations of liver total lipids and TAG decreased with increasing intake of RS, but that of liver cholesterol did not. There was significant positive correlation between the level of sterol regulatory element-binding protein-1c mRNA and concentration of liver TAG. Total SCFA amount in the caecum increased logarithmically with increasing dry weight of caecal contents. The amount of bile acids in the small intestinal content and the excretions of bile acids and neutral steroids in faeces increased with increasing RS intake. These results show that starch rich in RS is more effective in preventing ovarian hormone deficiency-induced hyperlipidaemia.

Resistant starches as a vehicle for delivering health benefits to the human large bowel

Non-starch polysaccharides (NSP; major components of dietary fibre) have been rather disappointing in the prevention and management of large bowel inflammatory diseases (IBD) or colorectal cancer (CRC). Resistant starch (RS) is that starch which escapes small intestinal digestion and enters the large bowel. RS contributes to total dietary fibre and could be as important as NSP in promoting large bowel health and preventing IBD and CRC. Indeed, it appears that some societies historically at low risk for these conditions eat relatively little NSP but have diets high in RS through their culinary practices. RS acts largely through its large bowel bacterial fermentation products which are, in adults, short chain fatty acids (SCFA). Collectively, SCFA have several non-specific positive actions on large bowel physiology including lowering of luminal pH. Of the major acids, butyrate has attracted the most attention. It is a major metabolic fuel for and promoter of a normal phenotype in colonocytes. Recent data from our laboratory support the latter suggestion. We have shown that, in rats, higher dietary protein (as casein, red meat or soy) increases colonocyte genetic damage and thinning of the colonic mucus barrier. However, feeding of RS as a high amylose maize starch opposed both of these changes in proportion to increased colonic butyrate. These data accord with prospective population data showing lower CRC risk with consumption of total dietary fibre. RS intakes appear to be low in most affluent industrialized countries, so increasing its consumption by modifying consumer foods is one strategy to improve public health. CSIRO and its partners are developing new high amylose cereal cultivars for this purpose. Colonic delivery of specific SCFA could also be useful clinically and we have shown that acetylated, propionylated and butyrylated starches resist small intestinal amylolysis. The bound SCFA are released by the large bowel microflora, raising their digesta levels, with the greatest increase being in the esterified acid. Feeding studies with butyrylated starch in rats have confirmed the opposition of diet-induced genetic damage, supporting a role for this SCFA in lowering risk of CRC and IBD. Further human and animal interventions are planned to determine the potential of these new types of RS in enhancing colonic health.

Resistant Starch Intakes in the United States

Objective Dietary fiber represents a broad class of undigested carbohydrate components. The components vary in chemical and physical nature and in their physiological outcomes. Resistant starch is starch that escapes digestion in the small intestine and that may be fermented in the large intestine. The purpose of this study was to estimate consumption of resistant starch by the US population and to identify key sources of dietary resistant starch. Design A database of resistant starch concentrations in foods was developed from the publicly available literature. These concentrations were linked to foods reported in 24-hour dietary recalls from participants in the 1999-2002 National Health and Nutrition Examination Surveys and estimates of resistant starch intakes were generated. Subjects The study population included 18,305 nonbreastfeeding individuals in the United States. Statistical analysis The dietary intake of resistant starch was determined for 10 US subpopulations defined by age, sex, and race/ethnicity. Three estimates of resistant starch intake were made for each person based on the minimum, mean, and maximum concentrations of resistant starch in the foods consumed. Results Americans aged 1 year and older were estimated to consume approximately 4.9 g resistant starch per day based on mean resistant starch concentrations (range 2.8 to 7.9 g resistant starch per day). Breads, cooked cereals/pastas, and vegetables (other than legumes) contributed 21%, 19%, and 19% of total resistant starch intake, respectively, and were top sources of resistant starch. Conclusions Findings from this study suggest that the estimated intake of resistant starch by Americans is approximately 3 to 8 g per person per day. These estimates of resistant starch intake provide a valuable reference for researchers and food and nutrition professionals and will allow for more accurate estimates of total intakes of carbohydrate compounds that escape digestion in the small intestine.

Long-term intake of resistant starch improves colonic mucosal integrity and reduces gut apoptosis and blood immune cells

Objective The potential effect of a long-term intake of resistant starch on colonic fermentation and on gut morphologic and immunologic indices of interest in bowel conditions in humans was studied in pigs. Methods Sixteen growing pigs were meal fed for 14 wk on a diet containing a large amount of raw potato starch (RPS; resistant starch) or corn starch (CS; digestible starch). Effects were assessed in the colon from the physicochemical properties of digesta and in the intestinal morphology, including lymphocytic infiltration, apoptosis, and proliferation activities. Hematologic and blood leukocyte cell subsets analysis were performed. Results After 97 d, the digestive content from RPS pigs was heavier than for CS pigs, producing a hypertrophy of tunica muscularis ( P < 0.05). The proportion of butyrate was two-fold higher in proximal colon digesta in RPS pigs ( P < 0.05). RPS-fed pigs had reduced apoptosis in the crypts, lamina propria and lymphoid nodules in the colon, and ileal Peyer’s patches ( P < 0.05). Fermentation of RPS reduced indices associated with damage to epithelial cells, such as crypt cell proliferation and magnesium excretion, whereas mucin sulfuration was increased, which promotes epithelial protection. The numbers of intraepithelial T cells and of blood leukocytes, neutrophils, and lymphocytes, mainly T-helper lymphocytes, were reduced in RPS pigs ( P < 0.05). Conclusion Long-term intake of RPS induces pronounced changes in the colonic environment, reduces damage to colonocytes, and improves mucosal integrity, reducing colonic and systemic immune reactivity, for which health benefits in inflammatory conditions are likely to be associated.

Dietary Fiber Intake in Two European Diets with High (Copenhagen, Denmark) and Low (Murcia, Spain) Colorectal Cancer Incidence

Contradictory results have been reported in studies associating dietary fiber (DF) intake and the incidence of colorectal cancer. Most studies focused mainly on the amount of total DF, but DF is a heterogeneous complex and its components are generally ignored. The aim of this work was to compare the amount and composition of DF intake in Murcia (Spain) and Copenhagen (Denmark). Total dietary fiber intake was a 31% higher in Murcia than in Copenhagen, the ratio of insoluble DF/soluble DF being similar in the two diets. DF in Murcia contains major amounts of nonstarch polysaccharides and polyphenolic compounds, mainly derived from the high consumption of fruits and vegetables (6.7 servings). Resistant starch intake was of the same order in the two regions while resistant protein intake was higher in Murcia. The quantitative and qualitative differences in DF intake may contribute to understand the differences in colorectal cancer incidence in Mediterranean and Scandinavian areas.

Increased probiotic yogurt or resistant starch intake does not affect isoflavone bioavailability in subjects consuming a high soy diet

Objective Probiotics and prebiotics that affect gut microflora balance and its associated enzyme activity may contribute to interindividual variation in isoflavone absorption after soy intake, possibly enhancing isoflavone bioavailability. This study examined the effects of the consumption of bioactive yogurt (a probiotic) or resistant starch (a known prebiotic) in combination with high soy intake on soy isoflavone bioavailability. Methods Using a crossover design, chronic soy consumption was compared with soy plus probiotic yogurt or resistant starch in older male and postmenopausal females ( n = 31). Isoflavone bioavailability was assessed at the beginning and end of each 5-wk dietary period by sampling plasma and urine after a standardized soy meal. Results Chronic soy intake did not significantly affect plasma or urinary isoflavones after the soy meal and there were no significant effects of probiotic or resistant starch treatment. However, there were trends for increased circulating plasma daidzein and genistein after the probiotic treatment and for increased plasma daidzein and genistein 24 h after soy intake with resistant starch treatment. Neither treatment induced or increased equol production, although there was a trend for increased plasma equol in “equol-positive” subjects ( n = 12) after probiotic treatment. Conclusion The weak or absence of effects of probiotic yogurt or resistant starch supplement to a chronic soy diet suggests that gut microflora were not modified in a manner that significantly affected isoflavone bioavailability or metabolism.

Resistant starch intakes in the United States

Resistant starch intakes in the United States

Dose‐dependent Effects of Resistant Potato Starch in the Diet on Intestinal Skatole Formation and Adipose Tissue Accumulation in the Pig

Resistant starch (RS) intake leads to a reduction of apoptosis in the pig colon and thus to a reduction of skatole in the carcass. To determine the minimal amount of RS which is required for the effect, diets with varying amounts (20, 30 and 40%) of RS were fed to barrows and gilts. Controls were fed instead with 55% pre-gelatinized starch. Skatole was determined after slaughter in distal colon content and in adipose tissue (flare fat and belly fat). Resistant starch led to a dose-dependent reduction of skatole in the gut content from 134 microg/g dry matter (controls) to 4.8 microg/g in the 40% group. Flare fat concentrations were decreased from 159 to 20 ng/g fat and belly fat concentrations from 64 to 16 ng/g fat. Strategies to improve sensorial quality by feeding RS continuously or for only 1 week prior to slaughter are discussed.

Health properties of resistant starch

Summary Resistant starch (RS) refers to the portion of starch and starch products that resist digestion as they pass through the gastrointestinal tract. RS is an extremely broad and diverse range of materials and a number of different types exist (RS1–4). At present, these are mostly defined according to physical and chemical characteristics. RS may be categorised as a type of dietary fibre, as defined by the American Association of Cereal Chemists and the Food Nutrition Board of the Institute of Medicine of the National Academies. RS is measured in part by the methodology recommended by the Association of Official Analytical Chemists for measuring dietary fibre. Dietary intakes of RS in westernised countries are likely to be low. However, accurate comparative assessments of dietary intakes between countries, and subsequent epidemiological analysis, are absent due to the lack of consensus over of an agreed, repeatable and simple in vitro method for analysing the RS content of foods. At present, the recognised method is that of McCleary &amp; Monaghan (2002). RS appears to confer considerable benefits to human colonic health, but has a smaller impact on lipid and glucose metabolism. Comparisons between studies are hampered by differences in study design, poor experimental design and differences in the source, type and dose of RS in the ingredients or diets used. It is likely that RS mediates some or all of its effects through the action of short chain fatty acids but interest is increasing regarding its prebiotic potential. There is also increasing interest in using RS to lower the energy value and available carbohydrate content of foods. RS can also be used to enhance the fibre content of foods and is under investigation regarding its potential to accelerate the onset of satiation and to lower the glycaemic response. Due to the difficulties in agreeing on a universal definition and method of analysis for dietary fibre, RS may be included within the term ‘fibre’ on the nutrition labels in some countries but not in others. Pressure to agree a legal definition and universal method of analysis is likely to increase due to the potential of RS to enhance colonic health, and to act as a vehicle to increase the total dietary fibre content of foodstuffs, particularly those which are low in energy and/or in total carbohydrate content.

Resistant Starch: Metabolic Effects and Potential Health Benefits

Although there is strong evidence that the amount and type of fat in the diet can have dramatic effects on metabolism, the case for carbohydrate subtypes influencing metabolic parameters is emerging. By definition, resistant starch (RS) is any starch that is not digested in the small intestine but passes to the large bowel. Here, RS is a good substrate for fermentation which gives rise to an increase in short-chain fatty acid production. The differing rates of absorption between RS and digestible starch are thought to denote their differential metabolic responses. RS intake is associated with several changes in metabolism which may confer some health benefits. RS intake seems to decrease postprandial glycemic and insulinemic responses, lower plasma cholesterol and triglyceride concentrations, improve whole body insulin sensitivity, increase satiety, and reduce fat storage. These properties make RS an attractive dietary target for the prevention of diseases associated with dyslipidemia and insulin resistance as well as the development of weight loss diets and dietary therapies for the treatment of Type 2 diabetes and coronary heart disease. This review analyzes the body of literature examining the metabolic effects of RS consumption and discusses possible mechanisms whereby increased short-chain fatty acid production in the bowel could account for some of these effects. The effects of RS in the large bowel per se are the topic of other reviews and are not addressed in this paper.

Anti-cancer effects of butyrate: use of micro-array technology to investigate mechanisms

Epidemiological evidence suggests that a high intake of resistant starch and NSP protects against colo-rectal cancer. The mechanisms underlying this protection are thought to be mediated by the short-chain fatty acid butyrate, which is present in the colonic lumen in millimolar concentrations as a result of bacterial fermentation of carbohydrates that have resisted digestion in the small intestine. In vitro studies have shown that butyrate displays a host of chemo-preventative properties including increased apoptosis, reduced proliferation, down regulation of angiogenesis, enhanced immunosurveillance and anti-inflammatory effects in colo-rectal cancer cell lines. However, the molecular mechanisms underlying the apparent chemo-preventative actions of butyrate are largely unknown. The evidence supporting the role of butyrate as an anti-cancer agent is reviewed, with particular emphasis on those studies that have attempted to elucidate the mechanism of action of butyrate. Our understanding of the mechanistic action of butyrate and its role in cancer prevention is likely to advance considerably in this post-genomic era with the application of genomic and proteomic technologies. Studies are described that have used gene array and proteomic techniques to investigate the response of colo-rectal cancer cells to butyrate. These pioneering studies illustrate the potential of these technologies to help characterise the molecular responses of the cancer cell to butyrate, and to define the role of butyrate (and other nutrients) in the prevention of colo-rectal cancer.

Resistant starch and β-glucan levels in grain sorghum ( Sorghum bicolor M.) are influenced by soaking and autoclaving

β-Glucan and resistant starch (RS) intake are linked to various physiological benefits. This study aimed to determine sorghum β-glucan and RS contents, and investigate the effects of processing on these. Grain sorghum was soaked at 37 °C for varying periods, then autoclaved at either 120 or 130 °C, and freeze-dried. Glucose, sucrose, β-glucan and RS levels were determined. Glucose content increased minimally with soaking. Sucrose content decreased from 0.90 g/100 g to 0.77 g/100 g with soaking. Autoclaving had little effect. β-Glucan content in unprocessed sorghum (0.12 g/100 g) increased with soaking and autoclaving at 120 °C. RS content increased from 6.5 g/100 g in unprocessed samples to 10.4 g/100 g with soaking. Autoclaving at 120 °C reduced RS content to a greater extent than at 130 °C. Moisture and heat processing therefore influence RS and β-glucan availability in sorghum.

Resistant starch content in a selection of starchy foods on the Swedish market.

The objective was to determine the resistant starch (RS) content in a selection of typical starchy foods on the Swedish market. In addition, the daily RS intake was estimated from Swedish food consumption data. The major forms of RS, including physically encapsulated starch, were determined with an in vitro method using chewing as a pre-step before enzymatic incubation. The study was performed at the Department of Applied Nutrition and Food Chemistry, Lund University, Sweden. Six healthy subjects were used to chew the food products before enzymatic incubation of the samples. Twenty-five cereal, potato and legume products were included in the study. The highest RS concentration was noted in the legume group (9.5-11.1% total starch basis). Commercially processed potato products were found to have a higher RS content (4.8-5.9%), compared with boiled potatoes (2.0%). Among the cereal products, bread with enclosure of intact rye grains, barley flakes and semolina porridge, respectively, were identified to have a RS level in the higher range (4.5-6.0%). The daily RS intake was estimated to be 3.2 g. The main RS sources in the Swedish diet are bread and potato products, which contribute approximately 1.3 and 1.2 g RS per day, respectively. Based on food habits the RS intake may vary considerably, thus when added to dietary fibre intake, the contribution of RS may be of nutritional importance for certain individuals.

Nutrient utilization in rats and pigs fed enzyme resistant starch

The influence of 6% dietary raw or retrograded high-amylose corn starch on protein, fat, carbohydrate, energy and mineral utilization was studied in rats and ileum-cannulated pigs fed the same conventional diets. Ileal nitrogen digestibility tended to decrease and faecal nitrogen excretion to increase in pigs fed one of the tested enzyme resistant starch (RS) sources. In rats, the effect from RS intake on faecal nitrogen excretion was more pronounced (P<0.05). These effects were paralleled by a shift of the nitrogen excretion from the renal to the faecal output. As a result, no significant effects from RS on nitrogen retention could be established in pigs and rats. RS consumption tended to lower apparent faecal fat digestibility in rats as well as apparent ileal and faecal fat digestibility in pigs. This effect on faecal fat digestibility was significant in pigs fed retrograded high-amylose corn starch. Faecal starch digestibility was significantly decreased in rats fed RS. Similar effects were found at the terminal ileum in pigs, but not at the anal level possibly due to more intensive fermentation in the large intestine of these animals. Apparent faecal digestible and metabolizable energy values were significantly lower in rats receiving RS. These effects were less pronounced in pigs, although RS intake significantly lowered apparent ileal energy digestibility when retrograded high-amylose corn starch was fed. In vivo determination of the RS concentrations in both test diets using ileum-cannulated pigs revealed values of 2.9% raw and 5.7% retrograded high-amylose corn starch instead of the 6% RS as measured in vitro, indicating that the tested retrograded starch behaved more like RS in the small intestine as compared with the raw starch. RS did not significantly affect apparent faecal absorption or retention of Ca, P, Mg and Zn in rats and pigs. In pigs, RS intake tended to decrease ileal absorption of the minerals, but these effects appeared to be neutralized in the large intestine. Despite the moderate dietary RS content, increases in faecal water content and bulking were found in rats and pigs. In conclusion, the investigated effects from RS ingestion were in general qualitatively similar in both species. Retrograded high-amylose corn starch, as compared with raw high-amylose corn starch, often exerted more pronounced effects, but the differences were not always significant.

Effect of enzyme resistant starch on large bowel fermentation in rats and pigs

The effect of raw and retrograded high-amylose corn starch, added to a semisynthetic or conventional diet, on the fermentation process in the cecum of the rat and in the proximal colon of the pig was investigated. A trophic effect on the rat cecal wall was observed when both types of diets were fed. Moreover, lower pH values were noted in rats as well as in pigs. There was no general inverse relation between cecal or colonic pH and L-lactic acid concentrations. Rats fed the enzyme resistant starch sources had significantly lower cecal ammonia concentrations, indicating higher bacterial activity resulting in increased conversion of ammonia to bacterial protein. A similar, however non-significant (P=0.06) effect was found in pigs. Generally, the mean cecal concentrations of volatile fatty acids were higher upon resistant starch feeding to rats given semi-synthetic diets, but the effects were only significant for butyrate and total volatile acid concentration when retrograded high-amylose corn starch was supplied. On the contrary, rats receiving resistant starch added to the conventional diet showed no significant influences on cecal butyric acid and total volatile fatty acid concentrations. Also in pigs, no significant effects of enzyme resistant starch intake on colonic volatile fatty acid concentrations were found. No significant effects of enzyme resistant starch intake on portal blood volatile fatty acid concentrations were observed in rats. In general, the amount of butyric acid as part of the total volatile acids was substantially lower in the portal blood as compared with the cecum, suggesting that butyric acid was greatly metabolized by the intestinal wall.

N-nitrosoproline formation in rats fed enzyme resistant starch

The aim of this work was to study the influence of raw or retrograded enzyme resistant starch (enzyme resistant starch type 2 or 3) feeding to rats on the faecal and urinary excretion of N-nitrosoproline, which is a valuable index of endogenous nitrosation. Rats were either concurrently treated with 2,500 ppm dietary proline and 3,000 ppm nitrite in their drinking water or not treated. The diets contained 0% or 6% resistant starch type 2 or 3. No N-nitrosoproline was detected in the faeces and the urine of non-treated animals. Intake of raw and retrograded enzyme resistant starch by animals receiving nitrite and proline caused a decreased output of total N-nitrosoproline by 24% and 14%, respectively. On average, 69% of the N-nitrosoproline output was found in the urine and the remainder in the faeces. The observed reduction of the endogenous formation of N-nitrosoproline might be due to an increase of the viscosity of the contents of the stomach and the small intestine, thus lowering the formation and/or absorption of N-nitrosoproline. Whether the decrease of the caecal pH following enzyme resistant starch intake had any effect on the in vivo bacterial formation of N-nitrosoproline could not be demonstrated in this study. Further research is necessary in order to clarify this inhibitory effect of enzyme resistant starch feeding.

Resistant starch in the Italian diet

Resistant starch (RS) has been defined as the sum of starch and starch-degradation products that reach the human large intestine (Champ, 1994), and it is now regarded as a sub-fraction of starch with a positive impact on colonic welfare and lipid metabolism. An early estimate of the RS intake in Europe gave an average value of approximately 4 g/d (Dyssler &amp; Hoffem, 1994a). However, since no information is available for Italy, the aim of the present study was to estimate the intake of RS in the Italian diet by direct analysis of RS in a range of typical foods representing the main sources of starch intake in the country. The selection of representative foods and of food consumption data were based on published results of the National Food Consumption Study conducted during the 1980s by the National Institute of Nutrition on 10 000 households, using weighed-food records plus inventory methodologies (Saba et al. 1990; Turrini et al. 1991). Three main groups of foods were considered: cereals (pasta, rice, bread and bread products, and pastries), potatoes, legumes. Different commercial brands for each sample were purchased, according to the known presence on the market. Samples were prepared ‘as eaten’ and submitted to simulated chewing, followed by total and resistant starch determination using the enzymic procedure published as a result of the EC Concerted Action EURESTA (Champ, 1992). From these results, the estimated average intake of RS in Italy was found to be 8.5 g/d, with regional differences (from 7.2 g/d in the north-west to 9.2 g/d in the south) mainly due to the different consumption of some typical Italian starchy food (bread, pasta, legumes).