The winemaking grape pomaces are rich in bioactive phytochemicals and dietary fibre (DF). DFs are phenolic-rich DF matrix and are dietary supplement with benefits on human health. As a result of the ...increased attention to sustainability of winemaking by-products, efforts have been made to use grape pomace in different bio-industries. In this review, we summarize the existing knowledge on the bioactivity and potential applications of DF from grape pomace, as well as the chemical compositions of DF. Furthermore, the biological activities of DF such as, anti-cancer activity, antibacterial activity, anti-inflammatory activity, antioxidant activity, improving gastrointestinal health activity, anti-apoptotic activity, preventing cardiovascular disease activity, anti-hypercholesterolemic activity, are discussed. Finally, the possible applications and future prospects of grape pomace DF in various fields are also summarised.
Polysaccharides derived from plant foods are major components of the human diet, with limited contributions of related components from fungal and algal sources. In particular, starch and other ...storage carbohydrates are the major sources of energy in all diets, while cell wall polysaccharides are the major components of dietary fiber. We review the role of these components in the human diet, including their structure and distribution, their modification during food processing and effects on functional properties, their behavior in the gastrointestinal tract, and their contribution to healthy diets.
Research into the analysis, physical properties and health effects of dietary fibre has continued steadily over the last 40–50 years. From the knowledge gained, countries have developed guidelines ...for their populations on the optimal amount of fibre to be consumed each day. Food composition tables from many countries now contain values for the dietary fibre content of foods, and, from these, combined with dietary surveys, population intakes have been determined. The present review assessed the uniformity of the analytical methods used, health claims permitted, recommendations and intakes, particularly from national surveys across Europe and around the world. It also assessed current knowledge on health effects of dietary fibre and related the impact of different fibre types on health. The overall intent was to be able to provide more detailed guidance on the types of fibre which should be consumed for good health, rather than simply a total intake figure, the current situation. Analysis of data indicated a fair degree of uniformity in the definition of dietary fibre, the method used for analysis, the recommended amount to be consumed and a growing literature on effects on digestive health and disease risk. However, national dietary survey data showed that intakes do not reach recommendations and very few countries provide guidance on the types of fibre that are preferable to achieve recommended intakes. Research gaps were identified and ideas suggested to provide information for more detailed advice to the public about specific food sources that should be consumed to achieve health benefits.
The interplay of gut microbiota, host metabolism, and metabolic health has gained increased attention. Gut microbiota may play a regulatory role in gastrointestinal health, substrate metabolism, and ...peripheral tissues including adipose tissue, skeletal muscle, liver, and pancreas via its metabolites short-chain fatty acids (SCFA). Animal and human data demonstrated that, in particular, acetate beneficially affects host energy and substrate metabolism via secretion of the gut hormones like glucagon-like peptide-1 and peptide YY, which, thereby, affects appetite, via a reduction in whole-body lipolysis, systemic pro-inflammatory cytokine levels, and via an increase in energy expenditure and fat oxidation. Thus, potential therapies to increase gut microbial fermentation and acetate production have been under vigorous scientific scrutiny. In this review, the relevance of the colonically and systemically most abundant SCFA acetate and its effects on the previously mentioned tissues will be discussed in relation to body weight control and glucose homeostasis. We discuss in detail the differential effects of oral acetate administration (vinegar intake), colonic acetate infusions, acetogenic fiber, and acetogenic probiotic administrations as approaches to combat obesity and comorbidities. Notably, human data are scarce, which highlights the necessity for further human research to investigate acetate's role in host physiology, metabolic, and cardiovascular health.
Dietary fibres are believed to reduce subjective appetite, energy intake and body weight. However, different types of dietary fibre may affect these outcomes differently. The aim of this review was ...to systematically investigate the available literature on the relationship between dietary fibre types, appetite, acute and long‐term energy intake, and body weight. Fibres were grouped according to chemical structure and physicochemical properties (viscosity, solubility and fermentability). Effect rates were calculated as the proportion of all fibre–control comparisons that reduced appetite (n = 58 comparisons), acute energy intake (n = 26), long‐term energy intake (n = 38) or body weight (n = 66). For appetite, acute energy intake, long‐term energy intake and body weight, there were clear differences in effect rates depending on chemical structure. Interestingly, fibres characterized as being more viscous (e.g. pectins, β‐glucans and guar gum) reduced appetite more often than those less viscous fibres (59% vs. 14%), which also applied to acute energy intake (69% vs. 30%). Overall, effects on energy intake and body weight were relatively small, and distinct dose–response relationships were not observed. Short‐ and long‐term effects of dietary fibres appear to differ and multiple mechanisms relating to their different physicochemical properties seem to interplay. This warrants further exploration.
Dietary fibre has been consumed for centuries with known health benefits, but defining dietary fibre is a real challenge. From a functional perspective, dietary fibre is described as supporting ...laxation, attenuating blood glucose responses and assisting with cholesterol lowering. The problem is different types of dietary fibre have different effects, and new effects are increasingly observed, such as the influence on gut microbiota. Thus, a single definition may need to be described in more generic terms. Rather than being bound by a few functional definitions, we may need to embrace the possibilities of new horizons, and derive a working definition of dietary fibre based on a set of conceptual principles, rather than the limited definitions we have to date. To begin this process, a review of individual fibre types and their physiological effects would be helpful. Dietary fibre is a complex group of substances, and there is a growing interest in specific effects linked to fibre type. Different fractions of dietary fibre have different physiological properties, yet there is a paucity of literature covering the effects of all fibres. This paper describes a range of individual fibre types and identifies gaps in the literature which may expose new directions for a working definition of dietary fibre.
Epidemiological studies have consistently demonstrated the benefits of dietary fibre on gastrointestinal health through consumption of unrefined whole foods, such as wholegrains, legumes, vegetables ...and fruits. Mechanistic studies and clinical trials on isolated and extracted fibres have demonstrated promising regulatory effects on the gut (for example, digestion and absorption, transit time, stool formation) and microbial effects (changes in gut microbiota composition and fermentation metabolites) that have important implications for gastrointestinal disorders. In this Review, we detail the major physicochemical properties and functional characteristics of dietary fibres, the importance of dietary fibres and current evidence for their use in the management of gastrointestinal disorders. It is now well-established that the physicochemical properties of different dietary fibres (such as solubility, viscosity and fermentability) vary greatly depending on their origin and processing and are important determinants of their functional characteristics and clinical utility. Although progress in understanding these relationships has uncovered potential therapeutic opportunities for dietary fibres, many clinical questions remain unanswered such as clarity on the optimal dose, type and source of fibre required in both the management of clinical symptoms and the prevention of gastrointestinal disorders. The use of novel fibres and/or the co-administration of fibres is an additional therapeutic approach yet to be extensively investigated.
Despite years of advising patients to alter their dietary and supplementary fiber intake, the evidence surrounding the use of fiber for functional bowel disease is limited. This paper outlines the ...organization of fiber types and highlights the importance of assessing the fermentation characteristics of each fiber type when choosing a suitable strategy for patients. Fiber undergoes partial or total fermentation in the distal small bowel and colon leading to the production of short-chain fatty acids and gas, thereby affecting gastrointestinal function and sensation. When fiber is recommended for functional bowel disease, use of a soluble supplement such as ispaghula/psyllium is best supported by the available evidence. Even when used judiciously, fiber can exacerbate abdominal distension, flatulence, constipation, and diarrhea.
The prevalence of lifestyle-related diseases is increasing in developing countries with the causes for death starting to follow the same pattern in the developed world. Lifestyle factors including ...inadequate dietary intake of fruits and vegetables and over consumption of nutrient-poor processed foods, are considered to be major causal risk factors associated with increased susceptibility to developing certain diseases (Alldrick,
1998
; Kiani,
2007
). Recent epidemiological evidence confirms a strong association between dietary fiber and reduced all-cause mortality risk, as well as a risk reduction for a number of non-communicable diseases (Chuang et al.,
2012
). The relationship between dietary fiber and mortality has been described as "convincing observations that call for mechanistic investigations" (Landberg,
2012
). In particular, the health protective roles played by dietary fibers of different origin are not well understood. Whilst Hippocrates was the earliest known physician to study the health benefits of fiber derived from grains (Burkitt,
1987
), the functionality of fruit and vegetable fiber, especially in association with other compounds such as polyphenols and carotenoids, is an area of more recent interest. Hence the objective of this review is to assess the complexity and health-related functional role of plant cell wall (PCW) fibers from fruits and vegetables with a particular emphasis on interactions between cell walls and phytonutrients.
The gut microbiota of individuals are dominated by different fiber-utilizing bacteria, which ferment dietary fiber into short chain fatty acids (SCFAs) known to be important for human health. Here, ...we show that the dominance of Prevotella versus Bacteroides in fecal innocula, identified into two different enterotypes, differentially impacts in vitro fermentation profiles of SCFAs from fibers with different chemical structures. In a microbiome of the Prevotella enterotype, fructooligosaccharides, and sorghum and corn arabinoxylans significantly promoted one single Prevotella OTU with equally high production of total SCFAs with propionate as the major product. Conversely, in the Bacteroides-dominated microbiota, the three fibers enriched different OTUs leading to different levels and ratios of SCFAs. This is the first report showing how individual differences in two enterotypes cause distinctly different responses to dietary fiber. Microbiota dominated by different fiber-utilizing bacteria may impact host health by way of producing different amounts and profiles of SCFAs from the same carbohydrate substrates.
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