Anthony Fardet

Parameters controlling the glycaemic response to breads.

Bread is one of the most widely consumed staple foods worldwide. White-wheat bread, largely consumed in France, is made from highly refined flour, which leads to a low nutrient density. Due to a highly porous structure and gelatinised starch, it is easily broken down during digestion, leading to a rapid increase of glucose released into the bloodstream. Low glycaemic responses are considered favourable to health, especially against a background of diabetes. Literature reports show that selection of raw material is an essential factor in decreasing the glycaemic index (GI) of white bread. There are two means of decreasing the rate of starch degradation: either (i) slowing gastric emptying rate and/or glucose diffusion-absorption through the intestinal mucosa, which can be achieved by incorporating soluble fibre or organic acid in bread, or (ii) limiting starch accessibility to alpha-amylase by using high-amylose cereal varieties and/or incorporating intact cereal grains. Studies on cereal products show that preservation of the food structure during digestion seems to be a more important GI-reducing factor than the degree of starch crystallinity or the presence of soluble fibre. Thus, we should look to produce bread with a more compact food structure or higher density, which is the case in leavened wholewheat bread or bread with intact cereal grains. The baking process should also be improved to achieve this goal, by using, for example, a reduced kneading time or less yeast than usual.

Associations between food and beverage groups and major diet‐related chronic diseases: an exhaustive review of pooled/meta‐analyses and systematic reviews

Associations between food and beverage groups and the risk of diet-related chronic disease (DRCD) have been the subject of intensive research in preventive nutrition. Pooled/meta-analyses and systematic reviews (PMASRs) aim to better characterize these associations. To date, however, there has been no attempt to synthesize all PMASRs that have assessed the relationship between food and beverage groups and DRCDs. The objectives of this review were to aggregate PMASRs to obtain an overview of the associations between food and beverage groups (n = 17) and DRCDs (n = 10) and to establish new directions for future research needs. The present review of 304 PMASRs published between 1950 and 2013 confirmed that plant food groups are more protective than animal food groups against DRCDs. Within plant food groups, grain products are more protective than fruits and vegetables. Among animal food groups, dairy/milk products have a neutral effect on the risk of DRCDs, while red/processed meats tend to increase the risk. Among beverages, tea was the most protective and soft drinks the least protective against DRCDs. For two of the DRCDs examined, sarcopenia and kidney disease, no PMASR was found. Overweight/obesity, type 2 diabetes, and various types of cardiovascular disease and cancer accounted for 289 of the PMASRs. There is a crucial need to further study the associations between food and beverage groups and mental health, skeletal health, digestive diseases, liver diseases, kidney diseases, obesity, and type 2 diabetes.

A Liquid Chromatography−Quadrupole Time-of-Flight (LC−QTOF)-based Metabolomic Approach Reveals New Metabolic Effects of Catechin in Rats Fed High-Fat Diets

Unbalanced diets generate oxidative stress commonly associated with the development of diabetes, atherosclerosis, obesity and cancer. Dietary flavonoids have antioxidant properties and may limit this stress and reduce the risk of these diseases. We used a metabolomic approach to study the influence of catechin, a common flavonoid naturally occurring in various fruits, wine or chocolate, on the metabolic changes induced by hyperlipidemic diets. Male Wistar rats ( n = 8/group) were fed during 6 weeks normolipidemic (5% w/w) or hyperlipidemic (15 and 25%) diets with or without catechin supplementation (0.2% w/w). Urines were collected at days 17 and 38 and analyzed by reverse-phase liquid chromatography-mass spectrometry (LC-QTOF). Hyperlipidic diets led to a significant increase of oxidative stress in liver and aorta, upon which catechin had no effect. Multivariate analyses (PCA and PLS-DA) of the urine fingerprints allowed discrimination of the different diets. Variables were then classified according to their dependence on lipid and catechin intake (ANOVA). Nine variables were identified as catechin metabolites of tissular or microbial origin. Around 1000 variables were significantly affected by the lipid content of the diet, and 76 were fully reversed by catechin supplementation. Four variables showing an increase in urinary excretion in rats fed the high-fat diets were identified as deoxycytidine, nicotinic acid, dihydroxyquinoline and pipecolinic acid. After catechin supplementation, the excretion of nicotinic acid was fully restored to the level found in the rats fed the low-fat diet. The physiological significance of these metabolic changes is discussed.

Textural Images Analysis of Pasta Protein Networks to Determine Influence of Technological Processes

ABSTRACT The structure of pasta is largely governed by the presence of a structured protein network. This work analyzed the protein network textures of various cooked pasta products through textural image analysis. Six different pasta types were investigated: reference pasta made from durum semolina; pasta enriched with gluten proteins from soft wheat flour at 10 and 20%; autoclaved pasta; soft wheat flour pasta; and pasta made from reconstituted flour fractions. Pasta samples were sectioned, and each crosssection consisted of three distinct zones (central, intermediate, and external) based on the state of swelling of starch granules for each pasta product. Digital images of the protein network in each zone were acquired using confocal laser scanning microscopy. Textural image analysis was then performed. Similarities and differences in protein network texture were assessed by principal component, stepwise discriminant, and variance analyses. With the exception of autoclaved pasta, protein network structu...

Wheat Germ Supplementation of a Low Vitamin E Diet in Rats Affords Effective Antioxidant Protection in Tissues

Background: Oxidative stress is implicated in the etiology of many diseases, but most of clinical trials failed to demonstrate beneficial effects of antioxidant supplementation. Methods: In the present experiment, we assessed the mean-term effect of wheat germ supplementation, as a dietary source of vitamin E, on antioxidant protection in rat. Results: Feeding rats a 20% wheat germ diet significantly increased plasma and liver vitamin E levels, compared to the low vitamin E basal diet. Concurrently, wheat germ diet consumption strongly decreased the susceptibility of heart and liver lipids to oxidation, as well as the plasma. Wheat germ feeding did not change triglycerides (TG) nor total cholesterol concentrations in plasma or liver, resulting in higher vitamin E/ TG ratio compared to controls. Similar results were found with a diet in which wheat germ oil provided the same amount of vitamin E. Conclusions: Wheat germ appears thus very effective to improve antioxidant defense status, especially in tissues, irrespective of modifications of lipids status.

In vitro fermentation of beet fibre and barley bran, of their insoluble residues after digestion and of ileal effluents

Abstract: The main objective of this study was to determine the form in whichbeet and barley bran Ðbres reach the colon, and to evaluate the inNuence ofendogeneous compounds on their patterns of fermentation. Raw Ðbres (RF), cor-responding ileal effluents (IE) from pigs, and insoluble Ðbre residues (IR)extracted from IE, were fermented with human faecal inoculum for 24 h in an invitro batch system. For beet Ðbre, rate but not extent of cell wall sugars degrada-tion was increased (]34% at 6 h, P\0E05) after oroileal transit, due to a moreporous structure. For barley bran, oroileal conditions degraded endosperm com-pounds such as b-glucans, leading to a lower extent of cell wall glucose fermenta-tion compared with RF ([22% at 24 h, P\0E05). In the presence ofendogeneous substances, degradation of beet Ðbre polysaccharides was delayed(P\0E05) at each incubation time but that of barley bran Ðbre was unaltered.Compared to RF, IR and IE signiÐcantly exhibited lower acetate production forbeet Ðbre, and higher propionate and lower butyrate production for barley branafter 24 h. It is concluded that in vivo digestion modiÐed fermentation patterns ofboth Ðbres in a manner depending on botanical structure.J Sci Food Agric 75, 315E325 (1997)No. of Figures: 2. No. of Tables: 4. No. of References: 45Key words: dietary Ðbre, beet Ðbre, barley bran, ileal effluents, insoluble Ðbreresidues, in vitro fermentation, human faecal bacteria

Plant-Based Foods as a Source of Lipotropes for Human Nutrition: A Survey of In Vivo Studies

Increased consumption of plant products is associated with lower chronic disease prevalence. This is attributed to the great diversity of healthy phytochemicals present in these foods. The most investigated physiological effects have been their antioxidant, anti-carcinogenic, hypolipidemic, and hypoglycemic properties. Although less studied in humans, some compounds were very early on shown to be lipotropic in animals, i.e., the capacity to hasten the removal of fat from liver and/or reduce hepatic lipid synthesis or deposits by mainly increasing phospholipid synthesis via the transmethylation pathway for triglyceride-rich lipoprotein exportation from the liver and enhanced fatty acid β-oxidation and/or down- and up-regulation of genes involved in lipogenic and fatty acid oxidation enzyme synthesis, respectively. The main plant lipotropes are choline, betaine, myo-inositol, methionine, and carnitine. Magnesium, niacin, pantothenate, and folates also indirectly support the overall lipotropic effect. The exhaustive review of rat studies investigating phytochemical effect on hepatic lipid metabolism suggests that some fatty acids, acetic acid, melatonin, phytic acid, some fiber compounds, oligofructose, resistant starch, some phenolic acids, flavonoids, lignans, stilbenes, curcumin, saponins, coumarin, some plant extracts, and some solid foods may be lipotropic. However, this remains to be confirmed in humans, for whom intervention studies are practically non-existent. Supplemental materials are available for this article. Go to the publishers online edition of Critical Reviews in Food Science and Nutrition® to view the free supplemental file.

Gastrointestinal or simulated in vitro digestion changes dietary fibre properties and their fermentation

This study evaluated the effect of digestion on the chemical and physicochemical characteristics of dietary fibre and on its behaviour during fermentation. Three dietary fibre sources (wheat bran, barley bran and beet fibre) were recovered from ileal cannulated pigs after in vivo digestion and prepared by in vitro enzymatic treatment simulating digestion. Raw substrates and fibre residues were analysed for their chemical and physicochemical properties as well as their potential fermentation by human colonic bacteria. In vitro and in vivo treatments led to insoluble residues, enriched in cell wall polysaccharides, with similar cell wall sugar composition and physicochemical properties. Degradations of cell wall polysaccharides with losses of sugar residues occurred mainly after in vivo digestion, especially for pectins from beet fibre and β-glucans from barley bran. Solubilisation of β-glucans removed highly fermentable substrates for further fermentation. For beet fibre, removal of pectins led to increased hydration properties and faster fermentation of cell-wall polysaccharides. Enzymatic treatment simulated correctly the passage of fibre through the digestive tract, modifying the cell-wall matrix and predisposing the fibre to further fermentation.

Associations between diet-related diseases and impaired physiological mechanisms: a holistic approach based on meta-analyses to identify targets for preventive nutrition.

In nutrition research, analyzing the relationship between a diet-related chronic disease and impaired metabolism is a common reductionist approach. Meta-analyses have enabled quantification of these relationships. There is, however, a need for more holistic approaches to determine the sequence of connections between diseases and associated physiological mechanisms. The objective of this exhaustive review was to collect scientific evidence – with priority given to quantitative reviews – published between 1950 and 2011 to assess the relationships between major diet-related chronic diseases and deregulated mechanisms. The results revealed that diabetes and obesity are the key diseases that lead to all other diet-related chronic diseases, while cancer, cardiovascular disease, skeletal disease, and sarcopenia are endpoint diseases. Liver disease, kidney disease, digestive disease, and mental illness are consequences as well as causes of other diet-related chronic diseases. All diseases have multifactorial causes, and most result from decreased antioxidant status, acid-base imbalance, increased inflammatory status, impaired carbohydrate/lipid/one-carbon metabolism, impaired functioning of neurons and DNA transcription, hypertension, and/or modified digestive microflora. Nutritional strategies that focus on the prevention of obesity and diabetes should be prioritized in order to reduce the prevalence of other major chronic diseases.

The search for a new paradigm to study micronutrient and phytochemical bioavailability: From reductionism to holism

The study of micronutrient and phytochemical (MaP, i.e., non-energy nutrients) bioavailability has been mainly studied through a reductionist and pharmacological approach. This has led to associate one health effect to one MaP. However, human interventional studies have given conflicting and disappointing results about MaP supplementation. This is because the health effect is the result of the synergetic action of numerous MaPs supplied by foods and/or diets at nutritional doses. A food is not a drug. Therefore, there is a need for more holistic approach to study MaP bioavailability, then their health effect to achieve general recommendations. This paper aims to hypothesize for such a paradigm shift in this topic and to lay new foundations for research in MaP bioavailability.