The effect of food processing on the glycaemic index

Available carbohydrates are those absorbed via the small intestine and used in the metabolism (Livesey, 2005). Indigestible carbohydrates, on the other hand, are considered to be dietary fibre, which include non-starch polysac-charides (mostly of plant and algal origin), resistant starches (RS), oligosac-charides and sugar alcohols (polyols) (Champ et al., 2003). Older methods for measuring dietary fibre did not measure these indigestible carbohydrates completely, leading to an underestimation...

Micronutrients

Anti-obesity effects of dietary calcium have been demonstrated in rodents, in which calcium supplementation attenuates the development of high-fat diet-induced obesity, accelerates weight and fat loss under energy restriction conditions, and limits weight and fat gain during refeeding after weight loss (reviewed in reference 138). Dairy products were found to be more potent than supplemental calcium in these animal studies. In humans, observational studies have noted an inverse relationship...

Mechanisms calcium and the regulation of energy metabolism

How does calcium work Although the physiological or cell-biology basis for the changes in body weight and body fat has not been fully elucidated, a hypothesis has been developed by Zemel and co-workers (2000), based largely on experiments in the obese agouti mutant mouse (Jones et al., 1996, Shi et al., 2001, Xue et al., 1998, 2001, Zemel et al., 1995). The agouti protein is involved in the development of the wild-type coat colour of agoutis (South-American guinea pig-like rodents), mice and...

References

Atkinson r l (1999), 'Conjugated linoleic acid for altering body composition', in yurawecz m p, mossoba m m, kramer j k b, pariza m w, nelson g j (Eds), Advances in Conjugated Linoleic Acid Research, volume 1. Champaign, AOCS Press, pp. 348-353. azain m j, hausman d b, sisk m b, flatt w p and jewell d e (2000), 'Dietary conjugated linoleic acid reduces rat adipose tissue cell size rather than cell number', J. Nutr., 130, 1548-1554. banni s, heys s d and wahle k w j (2003), 'Conjugated linoleic...

Role of resistant starch in weight management 831 Weight management direct evidence

RS is by its very nature indigestible and so does not contribute directly to plasma blood glucose levels. Therefore, replacing digestible starch with RS is a natural fit for low-glycemic foods and diets. In a 2003 report, the World Health Organization (WHO) reviewed the strength of evidence on various factors that might promote or protect against weight gain and obesity. They assessed the totality of evidence, including randomized controlled trials (highest ranking), associated evidence and...

Safety and regulatory status

The fact that the Hoodia plant has been consumed by the San Bushmen as whole fresh plant or dried whole plant for thousands of years is an element in favour of its safety. However, it is not sufficient to definitely conclude that the plant, P57 and P57AS3 from H. gordonii are safe for human consumption. Since P57AS3 has been found to have similarities to the steroidal core of cardiac glycosides, long-term research is needed to determine appropriate dosage and potential contraindications, risks...

Central and nutritional control of adaptive thermogenesis

Adaptive thermogenesis is under central control. Exposure to cold and diet is detected by the brain, resulting in the activation of efferent pathways controlling energy dissipation. The SNS, which heavily innervates thermo-genic targets such as BAT and skeletal muscle, appears to be the main effector of this response (reviewed in references 4 and 42). The sympatho-adrenergic control of BAT thermogenesis is well understood (Fig. 4.2). In BAT, the noradrenaline released by the activated SNS...

Polyunsaturated fatty acids on energy metabolism and other factors connected to weight control

The mechanism behind the benefits of omega-3 PUFAs on energy metabolism is at present not completely understood. There are, however, many possibilities since these fatty acids have many different roles in a cell. For example, apart from being an energy source, fatty acids build up the cellular membranes, regulate gene expression and function as signalling molecules and as precursors for complex biologically active molecules such as, for example, eicosanoids (Simopoulos, 1999, Ruxton et al.,...

Nutrient partitioning between fat and muscle

Adipose tissue hypertrophy is enhanced when fatty acids and glucose are preferentially channeled to adipose tissue rather than to other tissues, and particularly to muscle, where their main metabolic fate is oxidation. Two important players in nutrient partitioning between fat and muscle are LPL and GLUT4, both of which are highly expressed in the two tissues. Disregulation or imbalances of these two activities in muscle and adipose tissue may contribute to obesity, or may even cause it. Muscle...

Conclusion

Dietary starch in general and RS in particular are being re-assessed for their contribution to health. A wealth of information collected over 20 years of research, from human and animal studies, supports the use of RS ingredients to enrich new and existing foods. Consumer research highlights the importance of food quality as a major determinant of consumer choice. RS is a versatile option for formulating high-quality foods with added physiological benefits for enhancing their marketability. In...

Sources of conjugated linoleic acid and estimated daily intake

In food, CLA is found in products from ruminants such as milk and meat, and products made from them such as cheese and cultured dairy products (Parodi, 2003). CLA has been shown to be produced in the rumen as a result of biohydrogenation from linoleic acid, a polyunsaturated fatty acid that is found in the pasture. Rumenic acid or 9c,11t-18 2 is the major CLA isomer produced. Biohydrogenation also produces 11t-18 1 fatty acid or vaccenic acid. CLA has also been shown to be produced in the...

The impact of different food components on satiety

In the past 20 years, numerous studies have been carried out to investigate the impact of different food components on satiety. Research has been done on three levels 1 Effects of food components on subjective ratings of hunger and satiety. 2 Effects of food components on energy intake. 3 Effects of food components on body weight and long-term energy balance. Much work has been done using a paradigm developed 20 years ago (Kissileff et al., 1984) consisting of a preload or a test meal, after...

Effects of mediumchain triglycerides on body weight and body fat

Animal and human studies indicate enhanced EE and satiety after MCT consumption these studies were conducted to determine if these characteristics translate into decreases in fat mass. In animals consuming MCT, body weight was lower, fat depots smaller (Lavau and Hashim, 1978 Bray et al., 1980 Baba et al., 1982 Geliebter et al., 1983 Crozier et al., 1987 Hill et al., 1993), and adipose size reduced (Baba et al., 1982 Crozier et al., 1987) with MCT compared with LCT. These experiments suggest...

Effects of structured lipids related to weight control

MCT derivatives produced by the interesterification process are referred to as structural lipids or structural TGs. Interesterification is a process by which LCFA, such as oleic acid, are introduced into the final product. In the case of MCT derivatives, the product created is a rearranged TG with both MCFA and LCFA, in the desired ratios, on the same glycerine molecule. The existence of physiological actions of structured lipids on body weight and composition is explored in this section. Human...

Starch composition and arrangement

Starch is a heterogeneous group when considering structure and conformation, and so too is RS. In order to select appropriate RSs for food development, a basic understanding of starch chemistry is useful. All RSs share one basic similarity - they are all glucose-based polymers. Starch is largely composed of two glucose polymers, either the straight chain (amylose) or the highly branched chain (amylopectin) (see Fig. 8.1). The chain type is dictated by the type of linkages between the glucose...

Sites and mechanisms of adaptive thermogenesis

In rodents, a major site of adaptive thermogenesis is brown adipose tissue (BAT). The main mechanism behind BAT thermogenesis relies on the activity of uncoupling protein 1 (UCP1), a mitochondrial inner membrane protein that is uniquely and abundantly expressed in brown adipocytes, which are mitochondria-rich cells (reviewed in references 3-5). When active, UCP1 leaks protons across the mitochondrial inner membrane, allowing dissipation of the proton electrochemical gradient generated by the...

Functional benefits of trans fatty acids

In the early 1990s partially hydrogenated fats could be found in essentially all fat applications that involved some kind of challenge to the fat composition. Partially hydrogenated fats were the most important and versatile ingredient for fat technologists. In simple terms, this role was based on three distinct properties (1) the high chemical stability against oxidation of the partially hydrogenated fats, corresponding to the significantly reduced levels of polyunsaturated fatty acids (PUFA)...

Alternative sweeteners nonnutritive sweeteners

The hedonic value of sugars due to their sweetness can be provided in foods and beverages by artificial sweeteners (non-caloric sweeteners) or polyols (low-caloric sweeteners), alternatively called sugar substitutes, sugar replac-ers or alternative sweeteners. High-intensity sweeteners provide sweeteness with negligible calories, although the sensation of their sweetness is often different from that of sugar. Saccharine, the oldest artificial sweetener is 300 times as sweet as sucrose....

Using food and food components to control lipogenesis and thermogenesis

In this section, foods and food components that have the potential to assist weight loss maintenance due to effects on lipogenesis, thermogenesis and or body composition are presented. Dietary fat is related to the etiology of obesity because of its high energy density, high hedonic value, delayed satiating capacity thus promoting passive overconsumption, low associated thermic effect and efficient storage capacity. This has fueled the market for low-fat and fat-free foods for weight...

Lipid complexation with starch

It has been recognized that the complexation of amylose with the free fatty acids and monoglycerides in foods occurs at various stages of food preparation, storage, and even during the digestion process. Such a complex not only results in significant changes in the physicochemical and functional properties of starch - e.g. a change in the starch x-ray diffraction pattern to 'V' type, reduced solubility, increase in gelatinization temperature, retarded retrogradation during storage (Eliasson et...

Effects of mediumchain triglycerides on energy expenditure

Many animal studies have shown that diets high in MCT increase thermo-genesis, leading to less fat deposition as compared with diets high in LCT (Bray et al., 1980 Baba et al., 1982 Geliebter et al., 1983 Rothwell and Stock, 1987). An animal study by Lasekan et al. (1992), showed lower weight gain and 8-13 greater EE in rats fed a 3 1 mixture of MCT and LCT in emulsion compared with only LCT. Overall, animal studies suggest the possibility for MCT to increase EE in humans, thus potentially...

Physiological factors influencing food intake

The regulation of food intake is a complex interaction between numerous signals acting both peripherally and centrally, each varying over time. Consuming a meal may be divided into three phases a pre-prandial, a prandial and a postprandial (pre-absorptive and post-absorptive) phase. In addition, food intake is usually divided into two phases satiation (meal termination) and satiety (absence of satiety leads to meal initiation). Roughly speaking, factors important during the prandial phase are...

Introduction mediumchain triglycerides and weight control

Medium Chain Fatty Acids And Pancreas

Conventional fats and oils are composed of glycerides of 12- to 18-carbon long-chain fatty acids (LCFA). These compounds are known as long-chain triglycerides (LCT) and are the predominant form of lipids in the diet. Lipids are an essential source of energy and essential fatty acids, and a vital component of body cells. Therefore, it would be beneficial to have a dietary fat with the added benefit of anti-obesity properties. Medium-chain triglycerides (MCT) have a number of unique...

Sources and properties of nondigestible oligosaccharides

Following worldwide authorities on chemical nomenclature and terminology (i.e. the International Union of Biochemistry (IUB) and the International Union of Pure and Applied Chemistry (IUPAC), an oligosaccharide is a molecule containing a small number of monosaccharide residues (degree of polymerisation, DP from 2 to 10). NDOs resist hydrolysis and digestion in the human digestive system and are partially or completely fermented by the colonic microbiota in the large intestine. 7.3.2 Chemical...

Carbohydrate type glycaemic response and weight control

It has been debated whether excess dietary carbohydrate can increase adipose stores. Although test animals are able to convert significant amounts of ingested carbohydrate into body fat, in humans, de novo lipogenesis from carbohydrate appears to be limited (Strawford et al., 2004). Despite this, excess dietary carbohydrate may indirectly increase body fat stores. Dietary carbohydrate, in the form of starch or sucrose, increases blood insulin levels, which in turn increase activity of the...

Definition of resistant starch

From a nutritional perspective, starches can be classified according to their digestive fate in the gastrointestinal tract. Starches can be fully digestible in the small intestine (either rapidly digested or slowly digested) or indigestible (resistant). Depending upon food consumption practices and individual gastrointestinal processes, it is possible that some digestible starch may Table 8.1 Known effects of RS on parameters relevant to weight management Resistant to digestion - does not...

Overview of nutrition and lipogenesis

Lipogenesis

Lipogenesis encompasses the processes of fatty acid synthesis and subsequent triacylglycerol synthesis, mainly from excess carbohydrate in the diet. The main sites of lipogenesis are liver and adipose tissue. A detailed overview of lipogenesis and other processes of lipid metabolism is presented in Chapter 1 and here only some specific aspects will be addressed. In humans, the main site of de novo synthesis of fatty acids is the liver. Fatty acid synthesis requires NADPH, acetyl coenzyme A...

Using calcium in functional food products

Generally, functional foods are neither dietetic products nor food supplements, but processed foods with distinctive added-value features such as health and well-being. In order to be able to differentiate themselves from the established products, food companies use specific health claims, among which the link between calcium and bone health is one of the most widely used and accepted claims worldwide. According to Leatherhead Food International (2005), the functional foods market in the five...

Hormonal and nutritional control of lipogenesis

Lipogenese Srebp Chrebp Glucose

Carbohydrate-rich diets stimulate lipogenesis in the liver by providing the energy and carbons required for it, because insulin secreted after carbohydrate-rich meals triggers the activation of key enzymes in the glycolytic and lipogenic pathways, and because both glucose (independent of insulin) and insulin favor an increment in the concentration of glycolytic and lipo-genic enzymes, and hence of liver lipogenic capacity, through the up-regulation of the expression levels and activity of key...

Future trends

The process of DNL has gained more and more attention over the last few years, and it seems that the enzymatic pathways involved are not only interesting targets for obesity therapy (Abu-Elheiga et al. 2001, 2003 Kuhajda et al. 2005) but also for the treatment of other diseases such as cancer (Kuhajda et al. 2000). Modern transgenic animal technology allowing inducible gain-of-function and loss-of-function manipulations of a target gene in a specific organ will help to better understand the...

Substances reducing the rate of de novo lipogenesis and their possible therapeutic potential for the control of obesity

C75, an inhibitor of the enzyme FAS, was initially developed for the treatment of certain cancers (Kuhajda et al. 2000) because many common human cancers express high levels of FAS. Subsequent tests revealed that systemic and intracerebroventricular (i.c.v.) administration of C75 in mice reduced food intake and body weight (Loftus et al. 2000), making FAS also an interesting target in the therapy of obesity. C75 blocks the conversion of malonyl-CoA into fatty acids and, hence, increases tissue...

Nondigestible oligosaccharides food intake and weight control a key role for gastrointestinal peptides

7.5.1 Involvement in the regulation of food intake from theory to experimental data Endocrine L-cells are distributed all along the intestinal tract, but are mostly present in the caeco-colon, where fermentation of NDO occurs (Orskov et al. 1989). Endocrine cells present in the intestinal mucosa secrete peptides involved in the regulation of food intake, and or pancreatic functions, the latter being called incretins glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP) . Among...