Harnessing the power of resistant starch: a narrative review of its health impact and processing challenges

Starch is a primary energy storage for plants, making it an essential component of many plant-based foods consumed today. Resistant starch (RS) refers to those starch fractions that escape digestion in the small intestine and reach the colon where they are fermented by the microflora. RS has been repeatedly reported as having benefits on health, but ensuring that its content remains in food processing may be challenging. The present work focuses on the impact RS on health and explores the different processes that may influence its presence in foods, thus potentially interfering with these effects. Clinical evidence published from 2010 to 2023 and studying the effect of RS on health parameters in adult populations, were identified, using PUBMED/Medline and Cochrane databases. The search focused as well on observational studies related to the effect of food processes on RS content. While processes such as milling, fermentation, cooking and heating seem to have a deleterious influence on RS content, other processes, such as cooling, cooking time, storage time, or water content, may positively impact its presence. Regarding the influence on health parameters, there is a body of evidence suggesting an overall significant beneficial effect of RS, especially type 1 and 2, on several health parameters such as glycemic response, insulin resistance index, bowel function or inflammatory markers. Effects are more substantiated in individuals suffering from metabolic diseases. The effects of RS may however be exerted differently depending on the type. A better understanding of the influence of food processes on RS can guide the development of dietary intake recommendations and contribute to the development of food products rich in RS.

Development and validation of a photographic food atlas of Middle Eastern Mediterranean diet: Toward improved understanding of traditional healthy and sustainable diets

Background

Middle Eastern Mediterranean diet (MEMD) is a traditional plant-based diet that is commonly consumed and increasingly popular, but not well studied in nutrition research. To facilitate the dietary assessment of MEMD, we developed and validated a photographic food atlas depicting a variety of foods and dishes consumed in the MEM region.

Methods

The photographic food atlas included 1,002 photos of 400 types of foods and traditional dishes photographed characterizing MEMD. Foods and dishes were prepared by a professional cook and were subsequently photographed as a series of photos depicting portion size options. In a validation study, 45 individuals aged 20-50 years were recruited to assess portion size estimation of 25 representative food-photo series for each item. The validity of portion size estimation was assessed by comparing actual and reported estimates using Pearson or Spearman correlation tests. Sizes of the differences between estimated portions and the actual served portion sizes were calculate as mean differences and standard deviations.

Results

In the validation study, there was a strong correlation (r > 0.7) between estimated portion size of actual foods for 7 food items, such as pita bread, milk, labneh, and tomatoes, a moderate correlation (< 0.5 | r | < 0.7) for 12 items, such as meat, chicken, and grapes, and weak correlation (r < 0.3) for 6 items, such as seeds. Underestimation of portion sizes was more commonly observed for food items quantified when using "grams" or "milliliters" as a unit of measurement. In contrast, when household measurements were used, the participants tended to overestimate the portion sizes of respective foods and dishes.

Conclusion

We developed and validated a photographic food atlas depicting a wide variety of foods and dishes typical for the MEMD. The application of the photographic food atlas may facilitate the accurate assessment of adherence to MEMD and support the understanding of its health and sustainability aspects. Further methodological work is warranted to extend the list of food items and to evaluate the validity of the food atlas among larger and more heterogeneous groups of participants.

Nutrition Transition in Europe: East-West Dimensions in the Last 30 Years—A Narrative Review

The current review aims to summarize published research on nutrition transition patterns (depicting changes in dietary consumption) in European populations over the last three decades (1990–2020), with a focus on East-West regional comparisons. Pubmed and Google-Scholar databases were searched for articles providing information on repeated dietary intakes in populations living in countries across Europe, published between January 1990 and July 2021. From the identified 18,031 articles, 62 were found eligible for review (17 from Eastern and 45 from Western European populations). Overall, both in Eastern and Western Europe, there have been pronounced changes in dietary consumption patterns over the last three decades characterized by reductions in average reported intakes of sugar, carbohydrates and saturated fats and increases in reported fruit and vegetable consumption. There has also been a tendency toward a reduction in traditional foods, such as fish, observed in some Mediterranean countries. Overall, these data suggests that European countries have undergone a nutrition transition toward adopting healthier dietary behaviors. These processes occurred already in the period 1990–2000 in many Western European, and in the last decades have been also spreading throughout Eastern European countries. Firm conclusions are hampered by the lack of standardized methodologies depicting changes in dietary intakes over time and the limited coverage of the full variety of European populations. Future studies based on standardized dietary assessment methods and representative for the whole range of populations across Europe are warranted to allow monitoring trends in nutrition transition within and among European countries.

Mapping the global evidence on nutrition transition: a scoping review protocol

INTRODUCTION

Nutrition transition has emerged as an important concept in health research used to describe shifts in dietary consumption and energy expenditure that coincide with economic, demographic and epidemiological changes at a population level. Better understanding of the shifts in dietary patterns across populations and their drivers could possibly hold the key to prevention of diet-related disease risk. An increasing number of studies have reported on nutrition transition in populations around the world, however, global evidence has not been summarised.

OBJECTIVE

This scoping review is aimed to identify, explore and map the literature on nutrition transition with a specific focus on dietary changes in populations across the world. The review would allow better clarification around the concept of nutrition transition, classification of published studies and provide a framework for further research.

METHODS AND ANALYSIS

The scoping review will be designed based on the methodology by Arksey and O'Malley, refined by Levac et al. and developed in conjunction with guidance on conducting systematic scoping reviews by Peters et al. The main research question addressed by the scoping review will be: 'What is the evidence on nutrition transition defined based on dietary changes reported in general adult population across the world?' Electronic databases (PubMed, ScienceDirect and Web of Science), grey literature sources and the reference lists of key studies will be searched to identify studies appropriate for inclusion in the review. Two reviewers will independently screen all abstracts and full-text studies for inclusion. Data will be abstracted into tables and logically organised according to items addressed in the specific research questions.

ETHICS AND DISSEMINATION

Dissemination of results will be sought through a peer-reviewed publication, conference presentations and stakeholder meetings. The data used are from publicly available secondary sources, so no ethical review would be required for this study.

Evaluation of New Technology-Based Tools for Dietary Intake Assessment-An ILSI Europe Dietary Intake and Exposure Task Force Evaluation

BACKGROUND

New technology-based dietary assessment tools, including Web-based programs, mobile applications, and wearable devices, may improve accuracy and reduce costs of dietary data collection and processing. The International Life Sciences Institute (ILSI) Europe Dietary Intake and Exposure Task Force launched this project to evaluate new tools in order to recommend general quality standards for future applications.

METHODS

A comprehensive literature search identified technology-based dietary assessment tools, including those published in English from 01/2011 to 09/2017, and providing details on tool features, functions and uses. Each of the 43 tools identified (33 for research and 10 designed for consumer use) was rated on 25 attributes.

RESULTS

Most of the tools identified (79%) relied on self-reported dietary intakes. Most (91%) used text entry and 33% used digital images to help identify foods. Only 65% had integrated databases for estimating energy or nutrients. Fewer than 50% contained any features of customization and about half generated automatic reports. Most tools reported on usability or reported validity compared with another assessment method (77%). A set of Best Practice Guidelines was developed for reporting dietary assessment tools using new technology.

CONCLUSIONS

Dietary assessment methods that utilize technology offer many advantages for research and are often preferable to consumers over more traditional methods. In order to meet general quality standards, new technology tools require detailed publications describing tool development, food identification and quantification, customization, outputs, food composition tables used, and usability/validity testing.

Lower educational level is a predictor of incident type 2 diabetes in European countries: the EPIC-InterAct study

BACKGROUND

Type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases worldwide. In high-income countries, low socioeconomic status seems to be related to a high incidence of T2DM, but very little is known about the intermediate factors of this relationship. Method We performed a case-cohort study in eight Western European countries nested in the EPIC study (n = 340, 234, 3.99 million person-years of follow-up). A random sub-cohort of 16,835 individuals and a total of 12,403 incident cases of T2DM were identified. Crude and multivariate-adjusted hazard ratios (HR) were estimated for each country and pooled across countries using meta-analytical methods. Age-, gender- and country-specific relative indices of inequality (RII) were used as the measure of educational level and RII tertiles were analysed.

RESULTS

Compared with participants with a high educational level (RII tertile 1), participants with a low educational level (RII tertile 3) had a higher risk of T2DM [HR: 1.77, 95% confidence interval (CI): 1.69-1.85; P-trend < 0.01]. The HRs adjusted for physical activity, smoking status and propensity score according to macronutrient intake were very similar to the crude HR (adjusted HR: 1.67, 95% CI: 1.52-1.83 in men; HR: 1.88, 95% CI: 1.73-2.05 in women). The HRs were attenuated only when they were further adjusted for BMI (BMI-adjusted HR: 1.36, 95% CI: 1.23-1.51 in men; HR: 1.32, 95% CI: 1.20-1.45 in women).

CONCLUSION

This study demonstrates the inequalities in the risk of T2DM in Western European countries, with an inverse relationship between educational level and risk of T2DM that is only partially explained by variations in BMI.

Effects of supplemented isoenergetic diets differing in cereal fiber and protein content on insulin sensitivity in overweight humans

BACKGROUND

Despite their beneficial effects on weight loss and blood lipids, high-protein (HP) diets have been shown to increase insulin resistance and diabetes risk, whereas high-cereal-fiber (HCF) diets have shown the opposite effects on these outcomes.

OBJECTIVE

We compared the effects of isoenergetic HP and HCF diets and a diet with moderate increases in both cereal fibers and dietary protein (Mix diet) on insulin sensitivity, as measured by using euglycemic-hyperinsulinemic clamps with infusion of [6,6-(2)H(2)]glucose.

DESIGN

We randomly assigned 111 overweight adults with features of the metabolic syndrome to 1 of 4 two-phased, 18-wk isoenergetic diets by group-matching. Per 3-d food protocols, the percentages of energy derived from protein and carbohydrates and the intake of cereal fiber per day, respectively, were as follows-after 6 wk: 17%, 52%, and 14 g (control); 17%, 52%, and 43 g (HCF); 28%, 43%, and 13 g (HP); 23%, 44%, and 26 g (Mix); after 18 wk: 17%, 51%, and 15 g (control); 17%, 51%, and 41 g (HCF); 26%, 45%, and 14 g (HP); and 22%, 46%, and 26 g (Mix). Eighty-four participants completed the study successfully and were included in the final analyses. Adherence was supported by the provision of tailored dietary supplements twice daily in all groups.

RESULTS

Insulin sensitivity expressed as an M value was 25% higher after 6 wk of the HCF diet than after 6 wk of the HP diet (subgroup analysis: 4.61 ± 0.38 compared with 3.71 ± 0.36 mg · kg(-1) · min(-1), P = 0.008; treatment × time interaction: P = 0.005). Effects were attenuated after 18 wk (treatment × time interaction: P = 0.054), which was likely explained by lower adherence to the HP diet. HP intake was associated with a tendency to increased protein expression in adipose tissue of the translation initiation factor serine-kinase-6-1, which is known to mediate amino acid-induced insulin resistance. Biomarkers of protein intake indicated interference of cereal fibers with dietary protein absorption.

CONCLUSION

Greater changes in insulin sensitivity after intake of an isoenergetic HCF than after intake of an HP diet might help to explain the diverse effects of these diets on diabetes risk. This trial is registered at clinicaltrials.gov as NCT00579657.

Estimating usual food intake distributions by using the multiple source method in the EPIC-Potsdam Calibration Study

Estimating usual food intake distributions from short-term quantitative measurements is critical when occasionally or rarely eaten food groups are considered. To overcome this challenge by statistical modeling, the Multiple Source Method (MSM) was developed in 2006. The MSM provides usual food intake distributions from individual short-term estimates by combining the probability and the amount of consumption with incorporation of covariates into the modeling part. Habitual consumption frequency information may be used in 2 ways: first, to distinguish true nonconsumers from occasional nonconsumers in short-term measurements and second, as a covariate in the statistical model. The MSM is therefore able to calculate estimates for occasional nonconsumers. External information on the proportion of nonconsumers of a food can also be handled by the MSM. As a proof-of-concept, we applied the MSM to a data set from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam Calibration Study (2004) comprising 393 participants who completed two 24-h dietary recalls and one FFQ. Usual intake distributions were estimated for 38 food groups with a proportion of nonconsumers > 70% in the 24-h dietary recalls. The intake estimates derived by the MSM corresponded with the observed values such as the group mean. This study shows that the MSM is a useful and applicable statistical technique to estimate usual food intake distributions, if at least 2 repeated measurements per participant are available, even for food groups with a sizeable percentage of nonconsumers.

The contribution of risk factors to the higher incidence of invasive and in situ breast cancers in women with higher levels of education in the European prospective investigation into cancer and nutrition

The authors investigated the role of known risk factors in educational differences in breast cancer incidence. Analyses were based on the European Prospective Investigation Into Cancer and Nutrition and included 242,095 women, 433 cases of in situ breast cancer, and 4,469 cases of invasive breast cancer. Reproductive history (age at first full-term pregnancy and parity), exposure to endogenous and exogenous hormones, height, and health behaviors were accounted for in the analyses. Relative indices of inequality (RII) for education were estimated using Cox regression models. A higher risk of invasive breast cancer was found among women with higher levels of education (RII = 1.22, 95% confidence interval (CI): 1.09, 1.37). This association was not observed among nulliparous women (RII = 1.13, 95% CI: 0.84, 1.52). Inequalities in breast cancer incidence decreased substantially after adjusting for reproductive history (RII = 1.11, 95% CI: 0.98, 1.25), with most of the association being explained by age at first full-term pregnancy. Each other risk factor explained a small additional part of the inequalities in breast cancer incidence. Height accounted for most of the remaining differences in incidence. After adjusting for all known risk factors, the authors found no association between education level and risk of invasive breast cancer. Inequalities in incidence were more pronounced for in situ breast cancer, and those inequalities remained after adjustment for all known risk factors (RII = 1.61, 95% CI: 1.07, 2.41), especially among nulliparous women.

Web-enabled and improved software tools and data are needed to measure nutrient intakes and physical activity for personalized health research

Food intake, physical activity (PA), and genetic makeup each affect health and each factor influences the impact of the other 2 factors. Nutrigenomics describes interactions between genes and environment. Knowledge about the interplay between environment and genetics would be improved if experimental designs included measures of nutrient intake and PA. Lack of familiarity about how to analyze environmental variables and ease of access to tools and measurement instruments are 2 deterrents to these combined studies. This article describes the state of the art for measuring food intake and PA to encourage researchers to make their tools better known and more available to workers in other fields. Information presented was discussed during a workshop on this topic sponsored by the USDA, NIH, and FDA in the spring of 2009.