Effect of the fat composition of a single high-fat meal on inflammatory markers in healthy young women

The aim of the present study was to examine the effect of a single high-fat meal with different fat quality on circulating inflammatory markers and gene expression in peripheral blood mononuclear cells (PBMC) to elucidate the role of fat quality on postprandial inflammation. A postprandial study with fourteen healthy females consuming three test meals with different fat quality was performed. Test days were separated by 2 weeks. Fasting and postprandial blood samples at 3 and 6 h after intake were analysed. The test meal consisted of three cakes enriched with coconut fat (43 % energy as saturated fat and 1 % energy as a-linolenic acid (ALA)), linseed oil (14 % energy as ALA and 30 % energy as saturated fat) and cod liver oil (5 % energy as EPA and DHA and 5 % energy as ALA in addition to 31 % energy as saturated fat). In addition, ex vivo PBMC experiments were performed in eight healthy subjects investigating the effects of EPA and ALA on release and gene expression of inflammatory markers. The IL-8 mRNA level was significantly increased after intake of the cod liver oil cake at 6 h compared with fasting level, which was significantly different from the effect observed after the intake of linseed cake. In contrast, no effect was seen on circulating level of IL-8. In addition, ALA and EPA were shown to elicit different effects on the release and mRNA expression levels of inflammatory markers in PBMC cultured ex vivo, with EPA having the most prominent proinflammatory potentia

Antioxidants and phytochemicals – a scoping review for Nordic Nutrition Recommendations 2023

Antioxidants are a collection of substances that may prevent or delay the oxidation of cellular components. The antioxidant defense system includes both endogenously produced antioxidants and dietary antioxidants. The consumption of dietary antioxidants has long been speculated to be important for the defense against cellular oxidation, inflammation, and other disease-related processes. In addition to the well-known dietary antioxidants, such as vitamin C, vitamin E, β-carotene, and selenium, whole plants and plant-products contain numerous compounds, called phytochemicals, with antioxidant properties. These phytochemicals are potentially important modulators of oxidative stress and have been linked to health beneficial effects. However, the mechanisms underlying these potential health beneficial effects are not well understood. Foods containing high levels of phytochemicals with antioxidant properties include berries, fruits, vegetables, whole grains, and nuts and seeds. The aim of this scoping review is to describe the evidence of the role of specific antioxidants and phytochemicals, but not foods rich in these substances, for health outcomes. Based on a literature search from 2011 to March 2022, we identified eight meta-analyses related to the current topic. These studies include evidence of the effect of resveratrol (present mainly in berries, grapes, and peanuts) on health outcomes related to cardiometabolic risk, blood pressure, obesity, oxidative stress, adipokines, inflammation, and bone quality. In summary, resveratrol did elicit several health beneficial effects. However, the magnitude of effects was low, and whether the effects are related to the redox properties of resveratrol is not known. Even though there is a large body of evidence linking a plant-based diet rich in antioxidants and phytochemicals to beneficial health effects, the role of specific antioxidants and phytochemicals is still unclear

Dietary Fiber, Gut Microbiota, and Metabolic Regulation—Current Status in Human Randomized Trials

New knowledge about the gut microbiota and its interaction with the host’s metabolic regulation has emerged during the last few decades. Several factors may affect the composition of the gut microbiota, including dietary fiber. Dietary fiber is not hydrolyzed by human digestive enzymes, but it is acted upon by gut microbes, and metabolites like short-chain fatty acids are produced. The short-chain fatty acids may be absorbed into the circulation and affect metabolic regulation in the host or be a substrate for other microbes. Some studies have shown improved insulin sensitivity, weight regulation, and reduced inflammation with increases in gut-derived short-chain fatty acids, all of which may reduce the risk of developing metabolic diseases. To what extent a dietary intervention with fiber may affect the human gut microbiota and hence metabolic regulation, is however, currently not well described. The aim of the present review is to summarize recent research on human randomized, controlled intervention studies investigating the effect of dietary fiber on gut microbiota and metabolic regulation. Metabolic regulation is discussed with respect to markers relating to glycemic regulation and lipid metabolism. Taken together, the papers on which the current review is based, suggest that dietary fiber has the potential to change the gut microbiota and alter metabolic regulation. However, due to the heterogeneity of the studies, a firm conclusion describing the causal relationship between gut microbiota and metabolic regulation remains elusive

Correction to: Plasma fatty acid levels and gene expression related to lipid metabolism in peripheral blood mononuclear cells: a cross-sectional study in healthy subjects

Unfortunately, after publication of this article [1], it was noticed that some corrections to Table 2 were not carried out. The corrected Table 2 can be seen below and the original article has also been updated to reflect this

Plasma fatty acid levels and gene expression related to lipid metabolism in peripheral blood mononuclear cells: a cross-sectional study in healthy subjects

Abstract Background Solid evidence indicates that intake of marine n-3 fatty acids lowers serum triglycerides and that replacing saturated fatty acids (SFA) with polyunsaturated fatty acids (PUFA) reduces plasma total cholesterol and LDL cholesterol. The molecular mechanisms underlying these health beneficial effects are however not completely elucidated. The aim of this study was therefore to investigate the expression of genes related to lipid metabolism in peripheral blood mononuclear cells (PBMC) depending on the plasma levels of n-6 and n-3 fatty acids and the SFA to PUFA ratio. Methods Fifty-four healthy subjects were grouped into tertiles (n = 18) based on plasma levels of n-6 and n-3 fatty acids and the SFA to PUFA ratio. The PBMC gene expression levels among subjects in the highest versus the lowest tertiles were compared. In total, 285 genes related to cholesterol and triglyceride metabolism were selected for this explorative study. Results Among the 285 selected genes, 161 were defined as expressed in the PBMCs. The plasma SFA to PUFA ratio was associated with the highest number of significantly different expressed genes (25 gene transcripts), followed by plasma n-6 fatty acid level (15 gene transcripts) and plasma n-3 fatty acid level (8 gene transcripts). In particular, genes involved in cholesterol homeostasis were significantly different expressed among subjects with high compared to low plasma SFA to PUFA ratio. Conclusion Genes involved in lipid metabolism were differentially expressed in PBMCs depending on the plasma fatty acid levels. This finding may increase our understanding of how fatty acids influence lipid metabolism at a molecular level in humans

Experiences of managing a gluten-free diet on multiple levels of society: a qualitative study

Background Coeliac disease (CD) is an immune-mediated enteropathy against dietary gluten. The treatment for CD is a strict life-long gluten-free (GF) diet, which has a profound effect on a person’s life. In recent years, there has been an increase in the availability of gluten-free products. This study investigates how people with CD experience and manage a GF diet. Methods Semi-structured, individual interviews were conducted in different areas of Norway. The analysis was guided by Interpretative Phenomenological Analysis. Participants with CD (n = 12) varied in terms of gender, age, family composition and time since diagnosed. Results The analysis revealed challenges for a GF diet at the individual, interpersonal, community and policy levels. At the individual level, the participants explained that it took time to gain knowledge about a GF diet, and they expressed uncertainty about the healthiness of a GF diet. At the interpersonal level, the feeling of being different and the fear of gluten contamination were barriers to the enjoyment of social meals. At the community level, the participants asked for a wider selection of tastier GF products to purchase and increased knowledge about CD among those who prepare and sell GF foods. At the policy level, the participants asked for political action to make GF products more affordable. Conclusions This study indicates that people with CD should be given information about how to manage a GF diet right after being diagnosed with CD. The food industry should be encouraged to produce healthy and tasty GF products

Replacing saturated fatty acids with polyunsaturated fatty acids increases the abundance of Lachnospiraceae and is associated with reduced total cholesterol levels—a randomized controlled trial in healthy individuals

Background Improving dietary fat quality strongly affects serum cholesterol levels and hence the risk of cardiovascular diseases (CVDs). Recent studies have identified dietary fat as a potential modulator of the gut microbiota, a central regulator of host metabolism including lipid metabolism. We have previously shown a significant reduction in total cholesterol levels after replacing saturated fatty acids (SFAs) with polyunsaturated fatty acids (PUFAs). The aim of the present study was to investigate the effect of dietary fat quality on gut microbiota, short-chain fatty acids (SCFAs), and bile acids in healthy individuals. In addition, to investigate how changes in gut microbiota correlate with blood lipids, bile acids, and fatty acids. Methods Seventeen participants completed a randomized, controlled dietary crossover study. The participants received products with SFAs (control) or PUFAs in random order for three days. Fecal samples for gut microbiota analyses and fasting blood samples (lipids, fatty acids, and bile acids) were measured before and after the three-day intervention. Results Of a panel of 40 bacteria, Lachnospiraceae and Bifidobacterium spp. were significantly increased after intervention with PUFAs compared with SFAs. Interestingly, changes in Lachnospiraceae, as well as Phascolarlactobacterium sp. and Eubacterium hallii, was also found to be negatively correlated with changes in total cholesterol levels after replacing the intake of SFAs with PUFAs for three days. No significant differences in SCFAs or bile acids were found after the intervention. Conclusion Replacing SFAs with PUFAs increased the abundance of the gut microbiota family of Lachnospiraceae and Bifidobacterium spp. Furthermore, the reduction in total cholesterol after improving dietary fat quality correlated with changes in the gut microbiota family Lachnospiraceae. Future studies are needed to reveal whether Lachnospiraceae may be targeted to reduce total cholesterol levels. Trial registration The study was registered at Clinical Trials ( https://clinicaltrials.gov/ , registration identification number: NCT03658681)