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Purpose: It has been proposed that a higher habitual protein intake may increase cancer risk, possibly via upregulated insulin-like growth factor signalling. Since a systematic evaluation of human studies on protein intake and cancer risk based on a standardised assessment of systematic reviews (SRs) is lacking, we carried out an umbrella review of SRs on protein intake in relation to risks of different types of cancer. Methods: Following a pre-specified protocol (PROSPERO: CRD42018082395), we retrieved SRs on protein intake and cancer risk published before January 22th 2024, and assessed the methodological quality and outcome-specific certainty of the evidence using a modified version of AMSTAR 2 and NutriGrade, respectively. The overall certainty of evidence was rated according to predefined criteria. Results: Ten SRs were identified, of which eight included meta-analyses. Higher total protein intake was not associated with risks of breast, prostate, colorectal, ovarian, or pancreatic cancer incidence. The methodological quality of the included SRs ranged from critically low (kidney cancer), low (pancreatic, ovarian and prostate cancer) and moderate (breast and prostate cancer) to high (colorectal cancer). The outcome-specific certainty of the evidence underlying the reported findings on protein intake and cancer risk ranged from very low (pancreatic, ovarian and prostate cancer) to low (colorectal, ovarian, prostate, and breast cancer). Animal and plant protein intakes were not associated with cancer risks either at a low (breast and prostate cancer) or very low (pancreatic and prostate cancer) outcome-specific certainty of the evidence. Overall, the evidence for the lack of an association between protein intake and (i) colorectal cancer risk and (ii) breast cancer risk was rated as possible. By contrast, the evidence underlying the other reported results was rated as insufficient. Conclusion: The present findings suggest that higher total protein intake may not be associated with the risk of colorectal and breast cancer, while conclusions on protein intake in relation to risks of other types of cancer are restricted due to insufficient evidence. [ABSTRACT FROM AUTHOR]

Introduction: This umbrella review aimed to investigate the evidence of an effect of dietary intake of total protein, animal and plant protein on blood pressure (BP), and hypertension (PROSPERO: CRD42018082395). Methods: PubMed, Embase and Cochrane Database were systematically searched for systematic reviews (SRs) of prospective studies with or without meta-analysis published between 05/2007 and 10/2022. The methodological quality and outcome-specific certainty of evidence were assessed by the AMSTAR 2 and NutriGrade tools, followed by an assessment of the overall certainty of evidence. SRs investigating specific protein sources are described in this review, but not included in the assessment of the overall certainty of evidence. Results: Sixteen SRs were considered eligible for the umbrella review. Ten of the SRs investigated total protein intake, six animal protein, six plant protein and four animal vs. plant protein. The majority of the SRs reported no associations or effects of total, animal and plant protein on BP (all "possible" evidence), whereby the uncertainty regarding the effects on BP was particularly high for plant protein. Two SRs addressing milk-derived protein showed a reduction in BP; in contrast, SRs investigating soy protein found no effect on BP. The outcome-specific certainty of evidence of the SRs was mostly rated as low. Discussion/conclusion: This umbrella review showed uncertainties whether there are any effects on BP from the intake of total protein, or animal or plant proteins, specifically. Based on data from two SRs with milk protein, it cannot be excluded that certain types of protein could favourably influence BP. [ABSTRACT FROM AUTHOR]

Purpose: Protein-rich foods show heterogeneous associations with the risk of type 2 diabetes (T2D) and it remains unclear whether habitual protein intake is related to T2D risk. We carried out an umbrella review of systematic reviews (SR) of randomised trials and/or cohort studies on protein intake in relation to risks of T2D. Methods: Following a pre-specified protocol (PROSPERO: CRD42018082395), we retrieved SRs on protein intake and T2D risk published between July 1st 2009 and May 22nd 2022, and assessed the methodological quality and outcome-specific certainty of the evidence using a modified version of AMSTAR 2 and NutriGrade, respectively. The overall certainty of evidence was rated according to predefined criteria. Results: Eight SRs were identified of which six contained meta-analyses. The majority of SRs on total protein intake had moderate or high methodological quality and moderate outcome-specific certainty of evidence according to NutriGrade, however, the latter was low for the majority of SRs on animal and plant protein. Six of the eight SRs reported risk increases with both total and animal protein. According to one SR, total protein intake in studies was ~ 21 energy percentage (%E) in the highest intake category and 15%E in the lowest intake category. Relative Risks comparing high versus low intake in most recent SRs ranged from 1.09 (two SRs, 95% CIs 1.02–1.15 and 1.06–1.13) to 1.11 (1.05–1.16) for total protein (between 8 and 12 cohort studies included) and from 1.13 (1.08–1.19) to 1.19 (two SRs, 1.11–1.28 and 1.11–1.28) (8–9 cohort studies) for animal protein. However, SRs on RCTs examining major glycaemic traits (HbA1c, fasting glucose, fasting insulin) do not support a clear biological link with T2D risk. For plant protein, some recent SRs pointed towards risk decreases and non-linear associations, however, the majority did not support an association with T2D risk. Conclusion: Higher total protein intake was possibly associated with higher T2D risk, while there is insufficient evidence for a risk increase with higher intakes of animal protein and a risk decrease with plant protein intake. Given that most SRs on plant protein did not indicate an association, there is possibly a lack of an effect. [ABSTRACT FROM AUTHOR]

Purpose: This umbrella review aimed to assess whether dietary protein intake with regard to quantitative (higher vs. lower dietary protein intake) and qualitative considerations (total, plant-based or animal-based protein intake) affects body weight (BW), fat mass (FM) and waist circumference (WC). Methods: A systematic literature search was conducted in PubMed, Embase and Cochrane Database of Systematic Reviews for systematic reviews (SRs) with and without meta-analyses of prospective studies published between 04 October 2007 and 04 January 2022. Methodological quality and outcome-specific certainty of evidence of the retrieved SRs were assessed by using AMSTAR 2 and NutriGrade, respectively, in order to rate the overall certainty of evidence using predefined criteria. Results: Thirty-three SRs were included in this umbrella review; 29 were based on randomised controlled trials, a few included cohort studies. In studies without energy restriction, a high-protein diet did not modulate BW, FM and WC in adults in general (all "possible" evidence); for older adults, overall certainty of evidence was "insufficient" for all parameters. Under hypoenergetic diets, a high-protein diet mostly decreased BW and FM, but evidence was "insufficient" due to low methodological quality. Evidence regarding an influence of the protein type on BW, FM and WC was "insufficient". Conclusion: "Possible" evidence exists that the amount of protein does not affect BW, FM and WC in adults under isoenergetic conditions. Its impact on the reduction in BW and FM under hypoenergetic conditions remains unclear; evidence for an influence of protein type on BW, FM and WC is "insufficient". [ABSTRACT FROM AUTHOR]

Introduction: In metabolomics, the investigation of associations between the metabolome and one trait of interest is a key research question. However, statistical analyses of such associations are often challenging. Statistical tools enabling resilient verification and clear presentation are therefore highly desired. Objectives: Our aim is to provide a contribution for statistical analysis of metabolomics data, offering a widely applicable open-source statistical workflow, which considers the intrinsic complexity of metabolomics data. Methods: We combined selected R packages tailored for all properties of heterogeneous metabolomics datasets, where metabolite parameters typically (i) are analyzed in different matrices, (ii) are measured on different analytical platforms with different precision, (iii) are analyzed by targeted as well as non-targeted methods, (iv) are scaled variously, (v) reveal heterogeneous variances, (vi) may be correlated, (vii) may have only few values or values below a detection limit, or (viii) may be incomplete. Results: The code is shared entirely and freely available. The workflow output is a table of metabolites associated with a trait of interest and a compact plot for high-quality results visualization. The workflow output and its utility are presented by applying it to two previously published datasets: one dataset from our own lab and another dataset taken from the repository MetaboLights. Conclusion: Robustness and benefits of the statistical workflow were clearly demonstrated, and everyone can directly re-use it for analysis of own data. [ABSTRACT FROM AUTHOR]

Purpose: Changes in dietary protein intake metabolically affect kidney functions. However, knowledge on potential adverse consequences of long-term higher protein intake (HPI) for kidney health is lacking. To summarise and evaluate the available evidence for a relation between HPI and kidney diseases, an umbrella review of systematic reviews (SR) was conducted. Methods: PubMed, Embase and Cochrane Database of SRs published until 12/2022 were searched for the respective SRs with and without meta-analyses (MA) of randomised controlled trials or cohort studies. For assessments of methodological quality and of outcome-specific certainty of evidence, a modified version of AMSTAR 2 and the NutriGrade scoring tool were used, respectively. The overall certainty of evidence was assessed according to predefined criteria. Results: Six SRs with MA and three SRs without MA on various kidney-related outcomes were identified. Outcomes were chronic kidney disease, kidney stones and kidney function-related parameters: albuminuria, glomerular filtration rate, serum urea, urinary pH and urinary calcium excretion. Overall certainty of evidence was graded as 'possible' for stone risk not to be associated with HPI and albuminuria not to be elevated through HPI (above recommendations (> 0.8 g/kg body weight/day)) and graded as 'probable' or 'possible' for most other kidney function-related parameters to be physiologically increased with HPI. Conclusion: Changes of the assessed outcomes may have reflected mostly physiological (regulatory), but not pathometabolic responses to higher protein loads. For none of the outcomes, evidence was found that HPI does specifically trigger kidney stones or diseases. However, for potential recommendations long-term data, also over decades, are required. [ABSTRACT FROM AUTHOR]

This umbrella review aimed at assessing whether a protein intake exceeding the current recommendation for younger (0.8 g/kg body weight [BW]/day) and older (1.0 g/kg BW/day) adults affects bone mineral density and fracture risk. Moreover, the effect of animal or plant protein was evaluated. A systematic literature search was conducted in PubMed, Embase, and Cochrane Database of Systematic Reviews for systematic reviews (SRs) with or without meta-analysis of prospective studies published between 11/2008 and 08/2021. Methodological quality, outcome-specific certainty of evidence, and overall certainty of evidence of the retrieved SRs were assessed using established tools and predefined criteria. Eleven SRs of randomized controlled trials (RCTs) and/or cohort studies were included. In SRs of cohort studies and RCTs, protein intake/kg BW/day ranged between 0.21–0.95 g (low intake) and > 1.24 g (high intake), respectively, and between 0.67–1.1 g (control groups) and 1.01–1.69 g (intervention groups), respectively. The vast majority of outcome-specific certainty of evidence was rated "low" or "very low." The overall certainty of evidence for an association (cohort studies) or effect (RCTs) of total, animal or plant protein intake on each of the investigated outcomes was rated "insufficient," with the exception of possible evidence for a reduced hip fracture risk by high vs. low protein intake. Since protein intakes in low/control and high/intervention groups were very heterogeneous and with low certainty of evidence, it remains unclear whether a dose above the current recommendation or type of protein intake (animal or plant protein) affects bone health overall. However, there is possible evidence for reduced hip fracture risk with high versus low protein intake. [ABSTRACT FROM AUTHOR]

Introduction: Selenium is important for human health. However, the selenium status and selenium intake of the German population has not been recorded in a representative study so far. Material and Methods: Thus, literature from the last 50 years was screened in a systematic way and the results of various studies were pulled together to shed light on the selenium status of the German population. Moreover, the selenium content of selected food items that were either found on the German market or grown in Germany was researched and evaluated. Results: Of 3542 articles identified, 37 studies met the inclusion criteria. These 37 studies comprised a total of 8,010 healthy adults living in Germany with a weighted arithmetic mean of 82 μg/l selenium in plasma or serum. The results will form a basis for interpreting upcoming results from national food consumption surveys. Furthermore, 363 selenium values for 199 food items were identified out of 20 data sources—published or analysed between 2002 and 2019. An estimation of the selenium intake of the German population will be possible with this data in future nutrition surveys. [ABSTRACT FROM AUTHOR]

There are many examples in clinical nutrition with individuals responding differently to a dietary intervention. Here, personalized nutritional recommendations could be targeted, tailoring interventions to address plurality in response. For this, we reconsidered two randomized controlled trials investigating whether two different supplementation doses of cholecalciferol resulted in an increased serum 25(OH)D concentration. Three different statistical methods were applied in order to identify participants who would enjoy an increased benefit from receiving a specific dose of cholecalciferol. We concluded that, for individuals with high baseline serum 25(OH)D concentrations, only the high supplementation dose will lead to a substantial increase in the serum 25(OH)D concentration. The presented statistical methods can be adequately used for more individualized approaches. [ABSTRACT FROM AUTHOR]

Purpose: The reference values for biotin intake for Germany, Austria and Switzerland lead back to a report in 2000. Following a timely update process, they were revised in 2020. Methods: For infants aged 0 to < 4 months, adequate biotin supply via human milk was assumed and in consequence the reference value reflects the amount of biotin delivered by human milk. For infants aged 4 to < 12 months, biotin intake was extrapolated from the reference value for younger infants. Due to missing data on average requirement, the reference values for biotin intake for children, adolescents and adults were derived based on observed intake levels. The reference value for lactating women considered in addition biotin losses via human milk. Results: The reference value for biotin intake for infants aged 0 to < 4 months was set at 4 µg/day and for infants aged 4 to < 12 months at 6 µg/day. In children and adolescents, the reference values for biotin intake ranged from 20 µg/day in children 1 to < 4 years to 40 µg/day in youths 15 to < 19 years. For adults including pregnant women, 40 µg/day was derived as reference value for biotin intake. For lactating women, this value was set at 45 µg/day. Conclusions: As deficiency symptoms of biotin do not occur with a usual mixed diet and the average requirement cannot be determined, reference values for an adequate biotin intake for populations from Germany, Austria and Switzerland were derived from biotin intake levels assessed in population-based nutrition surveys. [ABSTRACT FROM AUTHOR]

Glyphosate (N-[phosphonomethyl]-glycine) is the most widely used herbicide worldwide. Due to health concerns about glyphosate exposure, its continued use is controversially discussed. Biomonitoring is an important tool in safety evaluation and this study aimed to determine exposure to glyphosate and its metabolite AMPA, in association with food consumption data, in participants of the cross-sectional KarMeN study (Germany). Glyphosate and AMPA levels were measured in 24-h urine samples from study participants (n = 301). For safety evaluation, the intake of glyphosate and AMPA was calculated based on urinary concentrations and checked against the EU acceptable daily intake (ADI) value for glyphosate. Urinary excretion of glyphosate and/or AMPA was correlated with food consumption data. 8.3% of the participants (n = 25) exhibited quantifiable concentrations (> 0.2 µg/L) of glyphosate and/or AMPA in their urine. In 66.5% of the samples, neither glyphosate (< 0.05 µg/L) nor AMPA (< 0.09 µg/L) was detected. The remaining subjects (n = 76) showed traces of glyphosate and/or AMPA. The calculated glyphosate and/or AMPA intake was far below the ADI of glyphosate. Significant, positive associations between urinary glyphosate excretion and consumption of pulses, or urinary AMPA excretion and mushroom intake were observed. Despite the widespread use of glyphosate, the exposure of the KarMeN population to glyphosate and AMPA was found to be very low. Based on the current risk assessment of glyphosate by EFSA, such exposure levels are not expected to pose any risk to human health. The detected associations with consuming certain foods are in line with reports on glyphosate and AMPA residues in food. [ABSTRACT FROM AUTHOR]

The original article has been corrected. [ABSTRACT FROM AUTHOR]

Soy isoflavones (IF) are in the focus of biomedical research since more than two decades. To assess their bioactivity, IF are investigated in rats and mice as a model. As the biological activity of IF is affected by their biotransformation, our aim was to comprehensively compare the conjugative and microbial metabolism of daidzein and genistein in adult humans, rats and mice of both sexes. One identical soy extract and a validated LC-MS method were used for all studies. We detected considerable differences between the three species. In rats and mice, sex-specific differences were observed in addition. The major plasma phase II metabolites in humans were the 7-sulfo-4′-glucuronides (39-49 %) and, in case of genistein, also the diglucuronide (34 %), whereas in mice monosulfates (33-41 %) and monoglucuronides (30-40 %) predominated. In male rats the disulfates (23-62 %) and 7-sulfo-4′-glucuronides (19-54 %) were predominant, while in female rats the 7-glucuronides (81-93 %) exhibited highest concentrations. The portion of aglycones was low in humans (0.5-1.3 %) and rats (0.5-3.1 %) but comparatively high in mice (3.1-26.0 %), especially in the case of daidzein. Furthermore, substantial differences were observed between daidzein and genistein metabolism. In contrast to humans, all rats and mice were equol producer, independent of their sex. In conclusion, there are marked differences between humans, rats and mice in the profile of major metabolites following IF phase II metabolism. These differences may contribute to resolve inconsistencies in results concerning the bioactivity of IF and should be considered when applying findings of animal studies to humans, e.g., for risk assessment. [ABSTRACT FROM AUTHOR]

The effect of cloudy apple juice on fecal microbiota of type 2 diabetics was studied. Five volunteers consumed apple juice while 5 control volunteers received an isocaloric control beverage daily for 4 weeks. DGGE profile analysis showed high diversity between volunteers that did not change over the intervention period using primers for Firmicutes, Bacteroidetes, bifidobacteria, enterococci, and enterobacteria. An exception was observed using lactobacilli primers, perhaps as the result of the dietary influence. Consumption of apple juice was not correlated with changes in DGGE profiles. Quantitative PCR was used to investigate the effect of apple juice on bacterial counts in different subgroups. Apple juice did not lead to significantly ( p>0.05) different numbers of total bacteria, enterobacteria, bifidobacteria, lactobacilli, or Bacteroidetes, but caused a significant ( p<0.05) decrease in numbers of enterococci, and a smaller but also significant decrease in numbers of Firmicutes, when comparing before and after intervention with apple juice. [ABSTRACT FROM AUTHOR]

The effect of a daily intake of the probiotic strain Lactobacillus casei Shirota (LcS) on the colonisation of pathogens, specifically streptococci and Staphylococcus aureus, in the nose and throat of healthy human volunteers with low natural killer cell activity, was investigated in a randomised and controlled intervention study. The study consisted of a 2-week run-in phase, followed by a 4-week intervention phase. The probiotic treatment group received a fermented milk drink with LcS, while the placebo group received an equally composed milk drink without the probiotic additive. To isolate potential pathogenic streptococci and Staph. aureus, samples from the pharynx, as well as of both middle nasal meati, were taken, once after the run-in phase and once at the end of the intervention phase. Isolated bacteria were identified as either Staph. aureus and α- or β-haemolytic streptococci in a polyphasic taxonomical approach based on phenotypic tests, amplified ribosomal DNA restriction analysis genotyping, and 16S rRNA gene sequencing of representative strains. Salivary secretory immunoglobulin A (SIgA) was used as marker of protective mucosal immunity to evaluate whether LcS treatment influenced SIgA production. No statistically significant effect could be determined for intervention with LcS on the incidence of Staph. aureus in the nasal space, Staph. aureus in the pharyngeal space or for β-haemolytic streptococci and Streptococcus pneumoniae in the pharyngeal space. Thus, the intervention did not influence the nasopharyngeal colonisation with Gram-positive potential pathogens. Production of salivary SIgA as a potential means of microbiota modulation was also not affected. [ABSTRACT FROM AUTHOR]

Purpose: Adipose tissue-associated chronic inflammation is involved in the pathogenesis of obesity-related diseases. Dietary fatty acids are known to influence inflammatory processes. The aim of this study was to investigate, whether diets with regular fat contents but variable fat qualities affect adipose tissue-associated inflammation through the fatty acid composition of mesenteric adipose tissue (MAT). Methods: Obese Zucker rats were fed diets containing 7 % wt:wt rapeseed oil, corn oil, or lard for 10 weeks. Fatty acid composition and endocrine function regarding adipokines and cytokines of MAT, number of total CD3 T cells, and cytokine secretion of mesenteric lymph node (MLN)-derived lymphocytes were determined. Local effects in MAT and MLN were compared to systemic effects assessed in serum and peripheral blood mononuclear cells. Results: Fatty acid composition of MAT reflected dietary fatty acid intake, without affecting endocrine function. Feeding the lard diet for 10 weeks increased the serum adiponectin and TNF-α secretion of blood lymphocytes, whereas CD3 T cells in blood were decreased. No effects were seen for the secretion of adipokines and cytokines from MAT, the amount of T cells in MLN, and cytokine secretion of MLN lymphocytes. Conclusions: In conclusion, feeding obese rats a diet with regular fat content but variable fat sources for 10 weeks, changed the fatty acid composition of MAT but not its secretory properties or MLN functions. Although the local immune system was not influenced, lard-feeding induced minor changes in systemic immune function. [ABSTRACT FROM AUTHOR]

Purpose: The effect of polyphenol-rich cloudy apple juice (CloA) consumption on plasma parameters related to the obesity phenotype and potential effects of interactions between CloA and allelic variants in obesity candidate genes were assessed in obese men. Methods: In this controlled, randomized, and parallel study, n = 68, non-smoking, non-diabetic men with a BMI ≥27 kg/m received 750 mL/day CloA (802.5 mg polyphenols) or 750 mL/day control beverage (CB, isocaloric equivalent to CloA) for 4 weeks. Further, study participants were genotyped for single-nucleotide polymorphisms in PPARγ (rs1801282), UCP3 (rs1800849), IL-6 (rs1800795), FABP2 (rs1799883), INSIG2 (rs7566605), and PGC1 (rs8192678) genes. At the beginning and at the end of intervention plasma lipids, distinct adipokines and cytokines as well as anthropometric parameters were determined. Results: CloA compared to CB had no significant effect on plasma lipids, plasma adipokine and cytokine levels, BMI, and waist circumference. However, CloA consumption significantly reduced percent body fat compared to CB (∆ % body fat: CloA: −1.0 ± 1.3 vs. CB: −0.2 ± 0.9, p < 0.05). The IL-6-174 G/C polymorphism showed an interaction with body fat reduction induced by CloA. Solely in C/C, but not in G/C or G/G variants, a significant reduction in body fat after 4 weeks of CloA intervention was detectable. Conclusion: The observed diet-gene interaction might be a first indication for the impact of individual genetic background on CloA-mediated bioactivity on obesity-associated comorbidities. [ABSTRACT FROM AUTHOR]

Background: Vegetables and fruit provide a significant part of human nutrition, as they are important sources of nutrients, dietary fibre, and phytochemicals. However, it is uncertain whether the risk of certain chronic diseases can be reduced by increased consumption of vegetables or fruit by the general public, and what strength of evidence has to be allocated to such an association. Methods: Therefore, a comprehensive analysis of the studies available in the literature and the respective study results has been performed and evaluated regarding obesity, type 2 diabetes mellitus, hypertension, coronary heart disease (CHD), stroke, cancer, chronic inflammatory bowel disease (IBD), rheumatoid arthritis (RA), chronic obstructive pulmonary disease (COPD), asthma, osteoporosis, eye diseases, and dementia. For judgement, the strength of evidence for a risk association, the level of evidence, and the number of studies were considered, the quality of the studies and their estimated relevance based on study design and size. Results: For hypertension, CHD, and stroke, there is convincing evidence that increasing the consumption of vegetables and fruit reduces the risk of disease. There is probable evidence that the risk of cancer in general is inversely associated with the consumption of vegetables and fruit. In addition, there is possible evidence that an increased consumption of vegetables and fruit may prevent body weight gain. As overweight is the most important risk factor for type 2 diabetes mellitus, an increased consumption of vegetables and fruit therefore might indirectly reduces the incidence of type 2 diabetes mellitus. Independent of overweight, there is probable evidence that there is no influence of increased consumption on the risk of type 2 diabetes mellitus. There is possible evidence that increasing the consumption of vegetables and fruit lowers the risk of certain eye diseases, dementia and the risk of osteoporosis. Likewise, current data on asthma, COPD, and RA indicate that an increase in vegetable and fruit consumption may contribute to the prevention of these diseases. For IBD, glaucoma, and diabetic retinopathy, there was insufficient evidence regarding an association with the consumption of vegetables and fruit. Conclusions: This critical review on the associations between the intake of vegetables and fruit and the risk of several chronic diseases shows that a high daily intake of these foods promotes health. Therefore, from a scientific point of view, national campaigns to increase vegetable and fruit consumption are justified. The promotion of vegetable and fruit consumption by nutrition and health policies is a preferable strategy to decrease the burden of several chronic diseases in Western societies. [ABSTRACT FROM AUTHOR]

Probiotics have been shown to enhance immune defenses, but their mechanisms of action are only partially understood. We investigated the modulation of signal pathways involved in innate immunity in enterocytes by Lactobacillus johnsonii BFE 6128 isolated from 'Kule naoto', a Maasai traditional fermented milk product. This lactobacillus sensitized HT29 intestinal epithelial cells toward recognition of Salmonella enterica serovar Typhimurium by increasing the IL-8 levels released after challenge with this pathogen and by differentially modulating genes related to toll-like receptor (TLR) pathways and innate immunity. Thus, the modulation of pro-inflammatory mediators and TLR-pathway-related molecules may be an important mechanism contributing to the potential stimulation of innate immunity by lactobacilli at the intestinal epithelial level. [ABSTRACT FROM AUTHOR]

The organic food sales have been increasing during the recent years. It has been hypothesised that organically grown fruits are healthier based on their higher content of phytochemicals. However, data on the bioavailability of phytochemicals from organically or conventionally produced plant foods are scarce. Two human intervention studies were performed to compare the bioavailability of polyphenols in healthy men after ingestion of apples from different farming systems. The administered apples were grown organically and conventionally under defined conditions and characterised regarding their polyphenol content and antioxidant capacity. No significant differences in the polyphenol content and the antioxidant capacity from the organic and conventional farming system were observed. In the short-term intervention study, six men consumed either organically or conventionally produced apples in a randomized cross-over study. After intake of 1 kg apples, phloretin ( Cmax 13 ± 5 nmol/l, tmax 1.7 ± 1.2 h) and coumaric acid ( Cmax 35 ± 12 nmol/l, tmax 3.0 ± 0.8 h) plasma concentrations increased significantly ( P < 0.0001) in both intervention groups, without differences between the two farming systems. In the long-term intervention study, 43 healthy volunteers consumed organically or conventionally produced apples (500 g/day; 4 weeks) or no apples in a double-blind, randomized intervention study. In this study, 24 h after the last dosing regime, the apple intake did not result in increasing polyphenol concentrations in plasma and urine compared to the control group suggesting no accumulation of apple polyphenols or degradation products in humans. Our study suggests that the two farming systems (organic/conventional) do not result in differences in the bioavailability of apple polyphenols. [ABSTRACT FROM AUTHOR]

Obesity and energy restriction modulate the development of precancerous aberrant crypt foci (ACF) in animal models of colon cancer. Investigation of the major obesity-associated determinants for ACF-development and underlying mechanisms leading to ACF-modulation, such as changes in DNA damage or colonocytes hyperproliferation. Lean and obese Zucker rats fed ad libitum (a.l.) or obese pair fed (p.f.) were induced with 1,2-dimethylhydrazine (DMH) for colon cancer. Multiple regression analyses were performed to identify major metabolic factors correlated with ACF number and size (aberrant crypts/ACF). DNA damage is analyzed by the comet-assay, epithelial proliferation by immunohistochemistry. Aberrant crypt foci number was significantly elevated in Zucker obese a.l. (205.7 ± 65.4 vs. lean 9.5 ± 6.3, P < 0.05) and is reduced by pair feeding in Zucker obese rats (81.4 ± 28.5 vs. obese a.l., P < 0.05). Compared to lean the ACF size was higher in Zucker obese a.l. (2.1 ± 0.3 vs. lean 1.3 ± 0.2., P < 0.05) but is not reduced by pair feeding (1.7 ± 0.2; P > 0.05). While ACF number and size were modulated by genotype and/or pair feeding the DMH-induced DNA damage and hyperproliferation in colonocytes did not differ significantly between groups. Regression analysis showed that plasma parameters associated with lipid-metabolism (triglycerides, cholesterol, malondialdehyde) significantly correlated with the ACF number and size while parameters linked to carbohydrate-metabolism (glucose, insulin) were weaker determinants. Obesity or pair feeding-associated modulation of ACF correlate with parameters related to lipid-metabolism but is not accompanied by changes in DNA damage and proliferation. [ABSTRACT FROM AUTHOR]

Summary. Background: A recent prospective cohort study revealed that moderate wine consumption but not consumption of other alcoholic beverages is associated with a decreased risk of common cold. In contrast, wine constituents such as ethanol and polyphenols are known to suppress immunity. Aim of the study: We investigated whether acute intake of a moderate amount of alcohol modulates immune functions in healthy men and whether polyphenols in red wine with antioxidative and immunomodulatory potential induce changes in immune functions that differ from those induced by the consumption of the 12 % ethanol. Methods: Six healthy males with moderate alcohol consumption patterns randomly consumed a single dose of 500 ml of red wine (12 % ethanol), a 12 % ethanol dilution, dealcoholized red wine, and red grape juice, respectively. The following immune functions were measured before beverage consumption and 1, 3, and 24 h later: phagocytic activity and intensity of neutrophils and monocytes, production of tumor necrosis factor-alpha, interleukin-2, and interleukin-4, lymphocyte proliferation, and lytic activity of natural killer cells. Results: Acute consumption of a moderate amount of red wine and of a 12 % ethanol solution had no effect on immune functions in men. Acute consumption of polyphenol-rich beverages (dealcoholized red wine and red grape juice) also did not affect immunity. Conclusions: This study clearly shows that moderate consumption of alcohol at doses which inversely correlate with cardiovascular disease risk has no short-term effect on human immune cell functions. Acute intake of polyphenol-rich beverages such as red grape juice and dealcoholized red wine also does not affect immunity. [ABSTRACT FROM AUTHOR]

Summary. Background: The oxidative modification of LDL is considered to play a central role in the pathogenesis of atherosclerosis and coronary heart disease (CHD). Paraoxonase (PON1) protects LDL from oxidation and may therefore retard the developement of atherosclerosis. The PON1–192 polymorphism is associated with diminished PON1 concentrations and an increased risk for CHD in RR-allele subjects. Aim of the study: To investigate the effect of tomato juice consumption on PON1 activity and other parameters related to oxidative stress in healthy elderly subjects. Furthermore, the PON1–192 genotype has been determined in the volunteers in order to see whether possible treatment effects are related to the PON1–192 polymorphism. Methods: Fifty elderly subjects were randomly assigned to control (mineral water) or intervention group (tomato juice). Subjects of the tomato juice group consumed daily 330 mL tomato juice for 8 weeks. Antioxidant status was measured as LDL oxidation, plasma malondialdehyde, ferric reducing ability of plasma (FRAP) and PON1 activity. The PON1–192 polymorphism was determined by restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR). Plasma carotenoids were analyzed by HPLC. Results: Tomato juice consumption reduced LDL-oxidation and improved antioxidant status in R-allele carriers, but not in the QQ genotype group. PON1 activity increased irrespective of the genotype in both, control and intervention group. Conclusions: The changes in antioxidant status after tomato juice consumption seem to depend on the PON1–192 genotype. Healthy elderly, carrying the R-allele, could specificly reduce their higher cardiovascular risk by changing dietary habits. [ABSTRACT FROM AUTHOR]

Summary Background & Aims Dietary polyphenols, including anthocyanins, are suggested to be involved in the protective effects of red wine against cardiovascular diseases. Very little data are available concerning the bioavailability of anthocyanins, major sources of red pigmentation in red wine. The aim of this study was to compare changes in plasma malvidin-3-glucoside (M-3-G), a red wine anthocyanin, and its urinary excretion after ingestion of red wine, dealcoholized red wine and red grape juice. Design Six healthy male subjects were studied in a randomized cross over setting in a human nutrition research unit under controlled conditions. All subject consumed 500 mL of each beverage on separate days providing the following M-3-G quantities: red wine 68 mg, dealcoholized red wine 58 mg, and red grape juice 117 mg. M-3-G was measured by HPLC and photodiode detection. Results M-3-G was found in plasma and urine after ingestion of all the beverages studied. The aglycon, sulfate or glucuronate conjugates of M-3-G were not detected in plasma and urine. Increases in plasma M-3-G concentrations were not significantly different after the consumption of either red wine or dealcoholized red wine and were about two times less than those measured after consumption of red grape juice. This difference may be caused by the about two times higher M-3-G concentration determined in red grape juice. Area under the plasma concentration curves were as follows: 288±127nmol × h/L (red wine), 214±124nmol × h/L (dealcoholized red wine) and 662±210 nmol × h/L (red grape juice) and showed a linear relationship with the amount of anthocyanin consumed (mean±SD). Conclusions M-3-G is poorly absorbed after a single ingestion of red wine, dealcoholized red wine, or red grape juice and seems to be differentially metabolized as compared to other red grape polyphenols. Our results suggest that not anthocyanins such as M-3-G themselves but rather not yet ... [ABSTRACT FROM AUTHOR]

A correction to the article "Phase II metabolism of the soy isoflavones genistein and daidzein in humans, rats and mice: a cross-species and sex comparison" is presented.

Summary. Background:. The gut and immune system form a complex integrated structure that has evolved to provide effective digestion and defence against ingested toxins and pathogenic bacteria. However, great variation exists in what is considered normal healthy gut and immune function. Thus, whilst it is possible to measure many aspects of digestion and immunity, it is more difficult to interpret the benefits to individuals of variation within what is considered to be a normal range. Nevertheless, it is important to set standards for optimal function for use both by the consumer, industry and those concerned with the public health. The digestive tract is most frequently the object of functional and health claims and a large market already exists for gut-functional foods worldwide. Aim:. To define normal function of the gut and immune system and describe available methods of measuring it. Results:. We have defined normal bowel habit and transit time, identified their role as risk factors for disease and how they may be measured. Similarly, we have tried to define what is a healthy gut flora in terms of the dominant genera and their metabolism and listed the many, varied and novel methods for determining these parameters.It has proved less easy to provide boundaries for what constitutes optimal or improved gastric emptying, gut motility, nutrient and water absorption and the function of organs such as the liver, gallbladder and pancreas. The many tests of these functions are described.We have discussed gastrointestinal well being. Sensations arising from the gut can be both pleasant and unpleasant. However, the characteristics of well being are ill defined and merge imperceptibly from acceptable to unacceptable, a state that is subjective. Nevertheless, we feel this is an important area for future work and method development.The immune system is even more difficult to make quantitative judgements about. When it is defective, then clinical problems ensure, but this is an uncommon state. The innate and adaptive immune systems work synergistically together and comprise many cellular and humoral factors. The adaptive system is extremely sophisticated and between the two arms of immunity there is great redundancy, which provides robust defences. New aspects of immune function are discovered regularly. It is not clear whether immune function can be „improved“.Measuring aspects of immune function is possible but there is no one test that will define either the status or functional capacity of the immune system. Human studies are often limited by the ability to sample only blood or secretions such as saliva but it should be remembered that only 2% of lymphocytes circulate at any given time, which limits interpretation of data.We recommend assessing the functional capacity of the immune system by:measuring specific cell functions ex vivomeasuring in vivo responses to challenge, e. g. change in antibody in blood or response to antigensdetermining the incidence and severity of infection in target populations during naturally occurring episodes or in response to attenuated pathogens. [ABSTRACT FROM AUTHOR]