| 1. |
- Fridén, Michael, et al.
(författare)
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Effects of a low-carbohydrate high polyunsaturated fat diet or a healthy Nordic diet versus usual care on liver fat content and cardiometabolic risk factors in people with type 2 diabetes and prediabetes: a randomized controlled trial (NAFLDiet)
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Background: Previous trials have shown that plant-derived polyunsaturated fatty acids (PUFA) in place of saturated fat reduces liver fat, a prerequisite for non-alcoholic fatty liver disease (NAFLD). The effect on liver fat from a novel “anti-lipogenic diet” replacing carbohydrates with PUFA or a healthy Nordic diet (HND) higher in whole-grains but lower in saturated fat has not yet been examined. Objectives: To investigate the effects on changes in liver fat (primary outcome) and other cardiometabolic risk factors after 12 months of follow-up in individuals with prediabetes or T2D from three different diet comparisons: a low carbohydrate high PUFA (LCPUFA) diet versus a HND, a LCPUFA diet versus usual care (UC) and a HND versus UC. Methods: A three-arm parallel ad libitum randomized trial was conducted. Adult men and women (n=148) were randomized to one of the three diet groups. Participants in all groups received key food items on a monthly/bimonthly basis. Liver fat and cardiometabolic risk factors were assessed at baseline and after 12 months. Dietary adherence was assessed using weighed food diaries and objective biomarkers. General linear models were employed to estimate the intention-to-treat (ITT) effect. Results: Dietary adherence was high for all diet groups. Liver fat was reduced to a similar extent in the LCPUFA and the HND group compared to UC (-1.46% (95% CI: -2.42, -0.51)) and -1.76 % (95% CI: -2.96, -0.57), respectively. No difference in liver fat between LCPUFA and HND was observed. Body weight and HbA1c decreased more in the HND compared to the other diet groups whereas no differences were observed between LCPUFA and UC. Similar reductions in LDL-cholesterol were observed for the HND and the LCPUFA group compared to UC, but only the HND reduced triglycerides and C-reactive protein (CRP) compared with UC. No differences were observed for any other secondary outcomes.Conclusions: A LCPUFA diet and a HND both reduced liver fat as compared with UC. Given the sustained weight loss after the HND compared to the other groups, together with improvements in other cardiometabolic markers, the HND in particular seems to be useful for the treatment of T2D and NAFLD.
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| 2. |
- Fridén, Michael, et al.
(författare)
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Hepatic Unsaturated Fatty Acids Are Linked to Lower Degree of Fibrosis in Non-alcoholic Fatty Liver Disease
- 2022
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Ingår i: Frontiers in Medicine. - : Frontiers Media SA. - 2296-858X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background: The hepatic lipidome of patients with early stages of non-alcoholic fatty liver disease (NAFLD) has been fairly well-explored. However, studies on more progressive forms of NAFLD, i.e., liver fibrosis, are limited. Materials and methods: Liver fatty acids were determined in cholesteryl esters (CE), phospholipids (PL), and triacylglycerols (TAG) by gas chromatography. Cross-sectional associations between fatty acids and biopsy-proven NAFLD fibrosis (n = 60) were assessed using multivariable logistic regression models. Stages of fibrosis were dichotomized into none-mild (F0–1) or significant fibrosis (F2–4). Models were adjusted for body-mass index (BMI), age and patatin-like phospholipase domain-containing protein 3 (PNPLA3 rs738409) (I148M) genotype. A secondary analysis examined whether associations from the primary analysis could be confirmed in the corresponding plasma lipid fractions. Results: PL behenic acid (22:0) was directly associated [OR (95% CI): 1.86 (1.00, 3.45)] whereas PL docosahexaenoic acid (22:6n-3) [OR (95% CI): 0.45 (0.23, 0.89)], TAG oleic acid (18:1n-9) [OR (95% CI): 0.52 (0.28, 0.95)] and 18:1n-9 and vaccenic acid (18:1n-7) (18:1) [OR (95% CI): 0.52 (0.28, 0.96)] were inversely associated with liver fibrosis. In plasma, TAG 18:1n-9 [OR (95% CI): 0.55 (0.31, 0.99)], TAG 18:1 [OR (95% CI): 0.54 (0.30, 0.97)] and PL 22:0 [OR (95% CI): 0.46 (0.25, 0.86)] were inversely associated with liver fibrosis. Conclusion: Higher TAG 18:1n-9 levels were linked to lower fibrosis in both liver and plasma, possibly reflecting an altered fatty acid metabolism. Whether PL 22:6n-3 has a protective role, together with a potentially adverse effect of hepatic 22:0, on liver fibrosis warrants large-scale studies.
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| 3. |
- Elmsjö, Albert, et al.
(författare)
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NMR-based metabolic profiling in healthy individuals overfed different types of fat : links to changes in liver fat accumulation and lean tissue mass.
- 2015
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Ingår i: Nutrition & Diabetes. - : Springer Science and Business Media LLC. - 2044-4052. ; 5:19, s. e182-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Overeating different dietary fatty acids influence the amount of liver fat stored during weight gain, however, the mechanisms responsible are unclear. We aimed to identify non-lipid metabolites that may differentiate between saturated (SFA) and polyunsaturated fatty acid (PUFA) overfeeding using a non-targeted metabolomic approach. We also investigated the possible relationships between plasma metabolites and body fat accumulation.METHODS: In a randomized study (LIPOGAIN study), n=39 healthy individuals were overfed with muffins containing SFA or PUFA. Plasma samples were precipitated with cold acetonitrile and analyzed by nuclear magnetic resonance (NMR) spectroscopy. Pattern recognition techniques were used to overview the data, identify variables contributing to group classification and to correlate metabolites with fat accumulation.RESULTS: We previously reported that SFA causes a greater accumulation of liver fat, visceral fat and total body fat, whereas lean tissue levels increases less compared with PUFA, despite comparable weight gain. In this study, lactate and acetate were identified as important contributors to group classification between SFA and PUFA (P<0.05). Furthermore, the fat depots (total body fat, visceral adipose tissue and liver fat) and lean tissue correlated (P(corr)>0.5) all with two or more metabolites (for example, branched amino acids, alanine, acetate and lactate). The metabolite composition differed in a manner that may indicate higher insulin sensitivity after a diet with PUFA compared with SFA, but this needs to be confirmed in future studies.CONCLUSION: A non-lipid metabolic profiling approach only identified a few metabolites that differentiated between SFA and PUFA overfeeding. Whether these metabolite changes are involved in depot-specific fat storage and increased lean tissue mass during overeating needs further investigation.
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| 4. |
- Fridén, Michael, et al.
(författare)
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Associations between fatty acid composition in serum cholesteryl esters and liver fat, basal fat oxidation, and resting energy expenditure : a population-based study
- 2021
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Ingår i: American Journal of Clinical Nutrition. - : Oxford University Press. - 0002-9165 .- 1938-3207. ; 114:5, s. 1743-1751
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We have repeatedly shown in short-term feeding trials that a high intake of dietary n-6 PUFAs, i.e. linoleic acid, prevents liver fat accumulation compared with saturated fat. However, population-based data is lacking and the mechanisms behind such effects are unclear.OBJECTIVE: To investigate associations between serum cholesteryl ester (CE) fatty acids and liver fat, basal fat oxidation [respiratory quotient (RQ)], and resting energy expenditure (REE). We hypothesized that PUFA in particular is inversely associated with liver fat and that such a relation is partly explained by a PUFA-induced increase in basal fat oxidation or REE.METHODS: Cross-sectional analyses using linear regression models in a population-based cohort with data on serum CE fatty acid composition and liver fat (n = 308).RESULTS: Linoleic acid (18:2n-6) (β = -0.03, 95% CI: -0.06, -0.001) and Δ5 desaturase index were inversely associated, whereas, γ-linolenic acid (18:3n-6) (β = 0.59, 95% CI: 0.28, 0.90), dihomo-γ-linolenic acid (20:3n-6) (β = 1.20, 95% CI: 0.65, 1.75), arachidonic acid (20:4n-6) (β = 0.08, 95% CI: 0.002, 0.16), palmitoleic acid (16:1n-7) (β = 0.37, 95% CI: 0.04, 0.70), Δ6 desaturase, and stearoyl CoA desaturase-1 (SCD-1) index were directly associated with liver fat after adjustment for confounders. Several serum CE fatty acids were correlated with both liver fat and REE, but only the association between DHA (22:6n-3) and liver fat was clearly attenuated after adjustment for REE (from β = -0.63 95% CI: -1.24, -0.02 to β = -0.34, 95% CI: -0.95, 0.27). Palmitoleic acid and SCD-1 were weakly inversely correlated with RQ but could not explain a lower liver fat content.CONCLUSIONS: Several serum CE fatty acids are associated with liver fat, among them linoleic acid. Although we identified novel associations between individual fatty acids and RQ and REE, our findings imply that PUFAs might prevent liver fat accumulation through mechanisms other than enhanced whole-body energy metabolism.
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| 5. |
- Fridén, Michael, et al.
(författare)
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Intake of Ultra-Processed Food and Ectopic-, Visceral- and Other Fat Depots : A Cross-Sectional Study.
- 2022
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Ingår i: Frontiers in nutrition. - : Frontiers Media S.A.. - 2296-861X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: The purpose of this study was to investigate associations between intake of ultra-processed food (UPF) and liver fat, pancreas fat and visceral adipose tissue (VAT) but also subcutaneous adipose tissue (SAT), VAT/SAT ratio and total fat mass.Materials and Methods: Cross-sectional analysis of n = 286 50-year old men and women. Energy percentage (%E) from UPF was calculated from a semi-quantitative food frequency questionnaire. Food items were categorized according to the NOVA-classification system and fat depots were assessed using magnetic resonance imaging (MRI) and bioelectrical impedance analysis (BIA). Associations were analyzed using linear regression, adjusted for sex, education, physical activity, smoking, dietary factors and BMI.Results: Mean intake of UPF was 37.8 ± 10.2 %E and the three largest contributors to this were crisp- and wholegrain breads and spreads, indicating overall healthy food choices. Consumption of UPF was associated with higher intake of energy, carbohydrates and fiber and lower intake of protein and polyunsaturated fat but no differences were observed for total fat, saturated fat (SFA), monounsaturated fat, sugar or alcohol between tertiles of UPF. Intake of UPF was positively associated with liver- and pancreas fat, VAT, VAT/SAT and inversely associated with total fat mass in crude models. The association for VAT remained after full adjustment (β = 0.01 (95% CI: 0.002, 0.02), P = 0.02) and was driven by women.Conclusion: Energy intake from UPF is not associated with ectopic fat, SAT or total fat after adjustment for multiple confounders in this population having overall healthy food habits. However, a positive association between UPF and VAT was observed which was driven by women.
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| 6. |
- Johansson, Hans-Erik, 1960-, et al.
(författare)
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Energy restriction in obese women suggest linear reduction of hepatic fat content and time-dependent metabolic improvements
- 2019
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Ingår i: Nutrition & Diabetes. - : Springer Science and Business Media LLC. - 2044-4052. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Energy restriction reduces liver fat, improves hepatic insulin resistance and lipid metabolism. However, temporal data in which these metabolic improvements occur and their interplay is incomplete. By performing repeated MRI scans and blood analysis at day 0, 3, 7, 14 and 28 the temporal changes in liver fat and related metabolic factors were assessed at five times during a low-calorie diet (LCD, 800-1100 kcal/day) in ten obese non-diabetic women (BMI 41.7 ± 2.6 kg/m2) whereof 6 had NAFLD. Mean weight loss was 7.4 ± 1.2 kg (0.7 kg/day) and liver fat decreased by 51 ± 16%, resulting in only three subjects having NAFLD at day 28. Marked alteration of insulin, NEFA, ALT and 3-hydroxybuturate was evident 3 days after commencing LCD, whereas liver fat showed a moderate but a linear reduction across the 28 days. Other circulating-liver fat markers (e.g. triglycerides, adiponectin, stearoyl-CoA desaturase-1 index, fibroblast growth factor 21) demonstrated modest and variable changes. Marked elevations of NEFA, 3-hydroxybuturate and ALT concentrations occurred until day 14, likely reflecting increased tissue lipolysis, fat oxidation and upregulated hepatic fatty acid oxidation. In summary, these results suggest linear reduction in liver fat, time-specific changes in metabolic markers and insulin resistance in response to energy restriction.
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| 7. |
- Rosqvist, Fredrik, 1985-, et al.
(författare)
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Abdominal Fat and Metabolic Health Markers but Not PNPLA3 Genotype Predicts Liver Fat Accumulation in Response to Excess Intake of Energy and Saturated Fat in Healthy Individuals
- 2020
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Ingår i: Frontiers in Nutrition. - : Frontiers Media SA. - 2296-861X. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Background: Saturated fat (SFA) has consistently been shown to increase liver fat, but the response appears variable at the individual level. Phenotypic and genotypic characteristics have been demonstrated to modify the hypercholesterolemic effect of SFA but it is unclear which characteristics that predict liver fat accumulation in response to a hypercaloric diet high in SFA.Objective: To identify predictors of liver fat accumulation in response to an increased intake of SFA.Design: We pooled our two previously conducted double-blind randomized trials (LIPOGAIN and LIPOGAIN-2, clinicaltrials.gov NCT01427140 and NCT02211612) and used data from the n = 49 metabolically healthy men (n = 32) and women (n = 17) randomized to a hypercaloric diet through addition of SFA-rich muffins for 7-8 weeks. Associations between clinical and metabolic variables at baseline and changes in liver fat during the intervention were analyzed using Spearman rank correlation. Linear regression was used to generate a prediction model.Results: Liver fat increased by 33% (IQR 5.4-82.7%; P < 0.0001) in response to excess energy intake and this was not associated (r = 0.17, P = 0.23) with the increase in body weight (1.9 kg; IQR 1.1-2.9 kg). Liver fat accumulation was similar (P = 0.28) in carriers (33%, IQR 14-79%) and non-carriers (33%, IQR -11 to +87%) of the PNPLA3-I148M variant. Baseline visceral and liver fat content, as well as levels of the liver enzyme gamma-glutamyl transferase (GT), were the strongest positive predictors of liver fat accumulation-in contrast, adiponectin and the fatty acid 17:0 in adipose tissue were the only negative predictors in univariate analyses. A regression model based on eight clinical and metabolic variables could explain 81% of the variation in liver fat accumulation.Conclusion: Our results suggest there exists a highly inter-individual variation in the accumulation of liver fat in metabolically healthy men and women, in response to an increased energy intake from SFA and carbohydrates that occurs over circa 2 months. This marked variability in liver fat accumulation could largely be predicted by a set of clinical (e.g., GT and BMI) and metabolic (e.g., fatty acids, HOMA-IR, and adiponectin) variables assessed at baseline.
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| 8. |
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| 9. |
- Rosqvist, Fredrik, 1985-, et al.
(författare)
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Fatty acid composition in serum cholesterol esters and phospholipids is linked to visceral and subcutaneous adipose tissue content in elderly individuals : a cross-sectional study
- 2017
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Ingår i: Lipids in Health and Disease. - : Springer Science and Business Media LLC. - 1476-511X. ; 16, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Visceral adipose tissue (VAT) and truncal fat predict cardiometabolic disease. Intervention trials suggest that saturated fatty acids (SFA), e. g. palmitic acid, promote abdominal and liver fat storage whereas polyunsaturated fatty acids (PUFA), e. g. linoleic acid, prevent fat accumulation. Such findings require investigation in population-based studies of older individuals. We aimed to investigate the relationships of serum biomarkers of PUFA intake as well as serum levels of palmitic acid, with abdominal and total adipose tissue content.Methods: In a population-based sample of 287 elderly subjects in the PIVUS cohort, we assessed fatty acid composition in serum cholesterol esters (CE) and phospholipids (PL) by gas chromatography and the amount of VAT and abdominal subcutaneous (SAT) adipose tissue by magnetic resonance imaging (MRI), liver fat by MR spectroscopy (MRS), and total body fat, trunk fat and leg fat by dual-energy X-ray absorptiometry (DXA). Insulin resistance was estimated by HOMA-IR.Results: VAT and trunk fat showed the strongest correlation with insulin resistance (r = 0.49, P < 0.001). Linoleic acid in both CE and PL was inversely related to all body fat depots (r = -0.24 to -0.33, P < 0.001) including liver fat measured in a sub-group (r = -0.26, P < 0.05, n = 73), whereas n-3 PUFA showed weak inverse (18: 3n-3) or positive (20: 5n-3) associations. Palmitic acid in CE, but not in PL, was directly correlated with VAT (r = 0.19, P < 0.001) and trunk fat (r = 0.18, P = 0.003). Overall, the significant associations remained after adjusting for energy intake, height, alcohol, sex, smoking, education and physical activity. The inverse correlation between linoleic acid and VAT remained significant after further adjustment for total body fat.Conclusions: Serum linoleic acid is inversely related to body fat storage including VAT and trunk fat whereas palmitic acid was less consistently but directly associated, in line with recent feeding studies. Considering the close link between VAT and insulin resistance, a potential preventive role of plant-based PUFA in VAT accumulation warrants further study.
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| 10. |
- Rosqvist, Fredrik, 1985-, et al.
(författare)
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Overeating saturated fat promotes fatty liver and ceramides compared to polyunsaturated fat : a randomized trial
- 2019
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : Oxford University Press. - 0021-972X .- 1945-7197. ; 104:12, s. 6207-6219
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Saturated fat (SFA) versus polyunsaturated fat (PUFA) may promote non-alcoholic fatty liver disease (NAFLD) by yet unclear mechanisms.OBJECTIVE: To investigate if overeating SFA- and PUFA-enriched diets lead to differential liver fat accumulation in overweight and obese humans.DESIGN: Double-blind randomized trial (LIPOGAIN-2). Overfeeding SFA vs PUFA for 8 weeks, followed by 4 weeks of caloric restriction.SETTING: General community.Participants: n=61 overweight or obese men and women.INTERVENTION: Muffins high in either palm (SFA)- or sunflower oil (PUFA) were added to the habitual diet.MAIN OUTCOME MEASURE: Lean tissue mass (not reported here). Secondary and exploratory outcomes included liver and ectopic fat depots.RESULTS: By design, body weight gain was similar in SFA (2.31±1.38 kg) and PUFA (2.01±1.90 kg) groups, P=0.50. SFA markedly induced liver fat content (50% relative increase) along with liver enzymes and atherogenic serum lipids. In contrast, despite similar weight gain, PUFA did not increase liver fat or liver enzymes or cause any adverse effects on blood lipids. SFA had no differential effect on the accumulation of visceral fat, pancreas fat or total body fat compared with PUFA. SFA consistently increased, while PUFA reduced circulating ceramides; changes that were moderately associated with liver fat changes and proposed markers of hepatic lipogenesis. The adverse metabolic effects of SFA were reversed by calorie restriction.CONCLUSIONS: Saturated fat markedly induces liver fat and serum ceramides whereas dietary polyunsaturated fat prevent liver fat accumulation, reduce ceramides and hyperlipidemia during excess energy intake and weight gain in overweight individuals.
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