European Journal of Nutrition (v.50, #1)
Health benefits of probiotics: are mixtures more effective than single strains? by C. M. C. Chapman; G. R. Gibson; I. Rowland (1-17).
Most studies on probiotics utilise single strains, sometimes incorporated into yoghurts. There are fewer studies on efficacy of mixtures of probiotic strains. This review examines the evidence that (a) probiotic mixtures are beneficial for a range of health-related outcomes and (b) mixtures are more or less effective than their component strains administered separately.Mixtures of probiotics had beneficial effects on the end points including irritable bowel syndrome and gut function, diarrhoea, atopic disease, immune function and respiratory tract infections, gut microbiota modulation, inflammatory bowel disease and treatment of Helicobacter pylori infection. However, only 16 studies compared the effect of a mixture with that of its component strains separately, although in 12 cases (75%), the mixture was more effective.Probiotic mixtures appear to be effective against a wide range of end points. Based on a limited number of studies, multi-strain probiotics appear to show greater efficacy than single strains, including strains that are components of the mixtures themselves. However, whether this is due to synergistic interactions between strains or a consequence of the higher probiotic dose used in some studies is at present unclear.
Keywords: Multi-strain probiotics; Health benefits; Synergy; Probiotic efficacy
Effects of de-alcoholised wines with different polyphenol content on DNA oxidative damage, gene expression of peripheral lymphocytes, and haemorheology: an intervention study in post-menopausal women by Lisa Giovannelli; Vanessa Pitozzi; Cristina Luceri; Lucia Giannini; Simona Toti; Simonetta Salvini; Francesco Sera; Jean-Marc Souquet; Veronique Cheynier; Francesco Sofi; Lucia Mannini; Anna Maria Gori; Rosanna Abbate; Domenico Palli; Piero Dolara (19-29).
Epidemiological studies suggest that a moderate consumption of wine is associated with a reduced risk of cardiovascular diseases and with a reduced mortality for all causes, possibly due to increased antioxidant defences. The present intervention study was undertaken to evaluate the in vivo effects of wine polyphenols on gene expression in humans, along with their supposed antioxidant activity.Blood haemorheology and platelet function were also evaluated. In order to avoid interferences from alcohol, we used de-alcoholised wine (DAW) with different polyphenol content. A randomised cross-over trial of high-proanthocyanidin (PA) red DAW (500 mL/die, PA dose = 7 mg/kg b.w.) vs. low-PA rosé DAW (500 mL/die, PA dose = 0.45 mg/kg) was conducted in 21 post-menopausal women in Florence, Italy. Oxidative DNA damage by the comet assay and gene expression by microarray was measured in peripheral blood lymphocytes, collected during the study period. Blood samples were also collected for the evaluation of haematological, haemostatic, haemorheological, and inflammatory parameters.The results of the present study provide evidence that consumption of substantial amounts of de-alcoholised wine for 1 month does not exert a protective activity towards oxidative DNA damage, nor modifies significantly the gene expression profile of peripheral lymphocytes, whereas it shows blood-fluidifying actions, expressed as a significant decrease in blood viscosity. However, this effect does not correlate with the dosage of polyphenols of the de-alcoholised wine.More intervention studies are needed to provide further evidence of the health-protective effects of wine proanthocyanidins.
Keywords: Proanthocyanidins; Wine; DNA damage; Comet assay; Microarray; Transcriptomics
Organic acid bioavailability from banana and sweet potato using an in vitro digestion and Caco-2 cell model by Houda Sabboh-Jourdan; Fanny Valla; Indah Epriliati; Michael J. Gidley (31-40).
Organic acids from plant food have been shown to play an important role in the prevention of chronic diseases (osteoporosis, obesity), inherent to western diets, but little is known about their bioavailability in the small intestine, information that needs to be determined in order to quantify likely effects on human health.An in vitro model of human digestion was carried out, comprising simulated oral, gastric and pancreatic digestion followed by an in vitro model of small intestine absorption using Caco-2 cell monolayers. As models for fruits and vegetables, freeze-dried or raw samples of banana and sweet potato were used.Organic acids have been found to be slowly released from the food matrix during simulated digestion of both banana and sweet potato, either raw or after freeze-drying. In the Caco-2 cell assay, malic and oxalic acids were absorbed more than citric acid. Oxalic and citric acids, but not malic acid, were transported across the cell monolayer. The release and uptake of major organic acids from model fruits and vegetables using established in vitro simulation processes was not quantitative and varied with acid type.Partial uptake is consistent with a dual nutritional role for organic acids as alkalinising agents (fraction which is taken up) and as modulators of large intestinal function (fraction which is not taken up in the small intestine). Studies of in vivo digestive release and uptake are needed in order to identify the contribution of organic acids to the nutritional value of fruits and vegetables.
Keywords: Organic acid; Bioaccessibility; Bioavailability; In vitro digestion; Caco-2 cell; Nutrition
Impact of substituting added sugar in carbonated soft drinks by intense sweeteners in young adults in the Netherlands: example of a benefit–risk approach by Marieke A. Hendriksen; Mariken J. Tijhuis; Heidi P. Fransen; Hans Verhagen; Jeljer Hoekstra (41-51).
Substituting added sugar in carbonated soft drinks with intense sweeteners may have potential beneficial, but also adverse health effects. This study assessed the benefits and risks associated with substituting added sugar in carbonated soft drinks with intense sweeteners in young adults in the Netherlands.A tiered approach was used analogous to the risk assessment paradigm, consisting of benefit and hazard identification, exposure assessment and finally benefit and risk characterization and comparison. Two extreme scenarios were compared in which all carbonated soft drinks were sweetened with either intense sweeteners or added sugar. National food consumption survey data were used, and intake of added sugar and intense sweeteners was calculated using the food composition table or analytical data for sweetener content.Reduction in dental caries and body weight were identified as benefits of substituting sugar. The mean difference in total energy intake between the scenarios was 542 kJ per day in men and 357 kJ per day in women, under the assumption that no compensation takes place. In the 100% sweetener scenario, the average BMI decreased 1.7 kg/m2 in men and 1.3 kg/m2 in women when compared to the 100% sugar scenario. Risks are negligible, as the intake of intense sweeteners remains below the ADI in the substitution scenario.Substitution of added sugar by intense sweeteners in carbonated soft drinks has beneficial effects on BMI and the reduction in dental caries, and does not seem to have adverse health effects in young adults, given the available knowledge and assumptions made.
Keywords: Benefit–risk assessment; Intense sweeteners; Added sugar; Carbonated soft drinks
Cloudy apple juice protects against chemical-induced oxidative stress in rat by Małgorzata Kujawska; Ewa Ignatowicz; Małgorzata Ewertowska; Jarosław Markowski; Jadwiga Jodynis-Liebert (53-60).
Apples abundant in phenolic compounds show a variety of biological activities that may contribute to beneficial effects against some chronic diseases.The aim of our study was to assess the protective effect of cloudy apple juice against chemical-induced oxidative stress in rats.Male Wistar rats were treated with apple juice per os, 10 mL/kg/day for 28 days and with a single dose of N-nitrosodiethylamine (NDEA), 150 mg/kg or carbon tetrachloride (CCl4), 2 mL/kg, 24 h before killing. Two groups of rats not pretreated with juice were administered each of the xenobiotics alone.Microsomal lipid peroxidation in the liver was decreased in rats pretreated with juice by 52–87% when compared to animals given NDEA or CCl4 alone. Pretreatment with juice protected antioxidant enzymes: catalase, glutathione peroxidase and glutathione reductase but not superoxide dismutase. Their activity was recovered by 49–173% when compared to that in rats given either toxicant alone. The plasma activity of paraoxonase1 was reduced by both toxicants and was increased by 23% in the apple/CCl4 group. A rise in plasma protein carbonyls caused by the xenobiotics was reduced by 20% only in apple/NDEA-treated rats. Also, in this group of animals, a 9% decrease in DNA damage in blood leukocytes was observed.Phytochemicals in commonly consumed apple juice may protect some macromolecules against oxidative insult induced by xenobiotics.
Keywords: Apple; Lipid peroxidation; Antioxidant enzymes; Comet assay; Protein carbonyls
A legume-based hypocaloric diet reduces proinflammatory status and improves metabolic features in overweight/obese subjects by Helen Hermana M. Hermsdorff; M. Ángeles Zulet; Itziar Abete; J. Alfredo Martínez (61-69).
The nutritional composition of the dietary intake could produce specific effects on metabolic variables and inflammatory marker concentrations. This study assessed the effects of two hypocaloric diets (legume-restricted- vs. legume-based diet) on metabolic and inflammatory changes, accompanying weight loss.Thirty obese subjects (17 M/13F; BMI: 32.5 ± 4.5 kg/m2; 36 ± 8 years) were randomly assigned to one of the following hypocaloric treatments (8 weeks): Calorie-restricted legume-free diet (Control: C-diet) or calorie-restricted legume-based diet (L-diet), prescribing 4 weekly different cooked-servings (160–235 g) of lentils, chickpeas, peas or beans. Body composition, blood pressure (BP), blood biochemical and inflammatory marker concentrations as well as dietary intake were measured at baseline and after the nutritional intervention.The L-diet achieved a greater body weight loss, when compared to the C-diet (−7.8 ± 2.9% vs. −5.3 ± 2.7%; p = 0.024). Total and LDL cholesterol levels and systolic BP were improved only when consuming the L-diet (p < 0.05). L-diet also resulted in a significant higher reduction in C-reactive protein (CRP) and complement C3 (C3) concentrations (p < 0.05), compared to baseline and C-diet values. Interestingly, the reduction in the concentrations of CRP and C3 remained significantly higher to L-diet group, after adjusting by weight loss (p < 0.05). In addition, the reduction (%) in CRP concentrations was positively associated with decreases (%) in systolic BP and total cholesterol concentration specifically in the L-diet group, independent from weight loss (p < 0.05).The consumption of legumes (4 servings/week) within a hypocaloric diet resulted in a specific reduction in proinflammatory markers, such as CRP and C3 and a clinically significant improvement of some metabolic features (lipid profile and BP) in overweight/ obese subjects, which were in some cases independent from weight loss.
Keywords: Legumes; Hypocaloric diet; Weight loss; Inflammation; C-reactive protein; Complement C3
Effects of high-fat and low-fat diets rich in monounsaturated fatty acids on serum lipids, LDL size and indices of lipid peroxidation in healthy non-obese men and women when consumed under controlled conditions by Sarah Egert; Mario Kratz; Frank Kannenberg; Manfred Fobker; Ursel Wahrburg (71-79).
To study the effects of the dietary fat content on cardiovascular disease risk factors in humans when the fatty acid composition and types of carbohydrates are kept constant.A controlled dietary study in healthy volunteers with 2 dietary groups and a parallel design consisting of 2 dietary periods was conducted. First, participants received a 2-week wash-in diet rich in saturated fatty acids (SFA; 47% of total fatty acids) and were then randomly assigned to either a high-fat (40% of energy) or a low-fat diet (29% of energy) for 4 weeks. Both diets were isocaloric, rich in monounsaturated fatty acids (MUFA; 51% of total fatty acids) and had similar fatty acid and carbohydrate compositions.Compared to the wash-in diet, the high-fat and low-fat diets significantly lowered LDL-cholesterol (−0.34 and −0.41 mmol/l, respectively; P < 0.001 for time effect in RM-ANOVA), and HDL-cholesterol (−0.13 and −0.18 mmol/l, respectively; P < 0.001 for time), without any differences between the high-fat and low-fat diets (P = 0.112 and P = 0.085 for time × group interaction in RM-ANOVA, respectively). The size of the major LDL fraction, the LDL susceptibility to oxidation and the plasma concentrations of oxidized LDL (ox-LDL) were significantly reduced by both the high-fat and low-fat diet, again without significant differences between the diets. The ratio of ox-LDL/LDL-cholesterol, serum triacylglycerols and urinary F2-isoprostanes were not significantly affected by the diets.A high-fat and a low-fat diet, both rich in MUFA, had similar effects on lipid-related cardiovascular disease risk factors in metabolically healthy men and women.
Keywords: Monounsaturated fatty acids; LDL oxidation; Lipoproteins; Dietary fat content