1. |
- Adamsson, Viola
(author)
-
A Healthy Nordic Diet and Cardiometabolic Risk Factors : Intervention Studies with Special Emphasis on Plasma Lipoproteins
- 2013
-
Doctoral thesis (other academic/artistic)abstract
- A healthy diet is important in the prevention of cardiovascular disease (CVD). Several risk factors, modifiable by diet, are involved in the development of CVD, e.g. hyperlipidaemia, hyperglycaemia, insulin resistance, obesity and hypertension. Little data however exist on diets composed of foods originating from the Nordic countries, and their potential to reduce CVD risk.This thesis aimed to investigate whether an ad libitum healthy Nordic diet (ND), either provided as a whole diet, or as a prudent breakfast (PB) alone, could influence CVD risk factors in healthy, mildly hypercholesterolemic men and women. Another aim was to describe the nutrient and food composition of the ND, both by using self-reported data and serum biomarkers of dietary fat quality.The primary clinical outcome measure was LDL-cholesterol, and other cardiometabolic risk factors were secondary outcomes.Two parallel, randomised, controlled intervention studies were conducted in free-living subjects. Clinical and dietary assessments were performed at baseline and at the end of dietary interventions. All foods were provided to subjects randomised to ND, whereas only breakfast items were supplied to subjects randomised to PB. Control groups followed their habitual diet/breakfast.Compared with controls, ND reduced body weight and improved several CVD risk factors including LDL-cholesterol, insulin sensitivity and blood pressure. Several, but not all effects were probably partly mediated by diet-induced weight loss. ND accorded with Nordic nutrition recommendations and was defined as “a plant-based diet, where animal products are used sparingly as side dishes”. Compared with average Swedish diet, ND was high in dietary fibre, but low in sodium, meat, high-fat dairy products, sweets and alcohol. A decreased intake of saturated fat and increased intake of n-3 PUFA during ND was partly reflected in serum lipids. Eating a PB without other dietary changes did not improve lipid or glucose metabolism, but decreased markers of visceral fat and inflammation, without influencing body weight.This thesis suggests that a whole ND, but not PB alone, promotes weight loss and improves multiple CVD risk factors in healthy subjects after 6 weeks. These results suggest that ND could have a potential role in the prevention of cardiometabolic diseases.
|
|
2. |
- Nerpin, Elisabet, 1962-
(author)
-
The Kidney in Different Stages of the Cardiovascular Continuum
- 2013
-
Doctoral thesis (other academic/artistic)abstract
- Patients with chronic kidney disease are at higher risk of developing cardiovascular disease. The complex, interaction between the kidney and the cardiovascular system is incompletely understood, particularly at the early stages of the cardiovascular continuum.The overall aim of this thesis was to clarify novel aspects of the interplay between the kidney and the cardiovascular system at different stages of the cardiovascular continuum; from risk factors such as insulin resistance, inflammation and oxidative stress, via sub-clinical cardiovascular damage such as endothelial dysfunction and left ventricular dysfunction, to overt cardiovascular death.This thesis is based on two community-based cohorts of elderly, Uppsala Longitudinal Study of Adult Men (ULSAM) and Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS).The first study, show that higher insulin sensitivity, measured with euglycemic-hyperinsulinemic clamp technique was associated to improve estimated glomerular filtration rate (eGFR) in participants with normal fasting plasma glucose, normal glucose tolerance and normal eGFR. In longitudinal analyses, higher insulin sensitivity at baseline was associated with lower risk of impaired renal function during follow-up. In the second study, eGFR was inversely associated with different inflammatory markers (C-reactive protein, interleukin-6, serum amyloid A) and positively associated with a marker of oxidative stress (urinary F2-isoprostanes). In line with this, the urinary albumin/creatinine ratio was positively associated with these inflammatory markers, and negatively associated with oxidative stress.In study three, higher eGFR was associated with better endothelial function as assessed by the invasive forearm model. Further, in study four, higher eGFR was significantly associated with higher left ventricular systolic function (ejection fraction). The 5th study of the thesis shows that higher urinary albumin excretion rate (UAER) and lower eGFR was independently associated with an increased risk for cardiovascular mortality. Analyses of global model fit, discrimination, calibration, and reclassification suggest that UAER and eGFR add relevant prognostic information beyond established cardiovascular risk factors in participants without prevalent cardiovascular disease.Conclusion: this thesis show that the interaction between the kidney and the cardiovascular system plays an important role in the development of cardiovascular disease and that this interplay begins at an early asymptomatic stage of the disease process.
|
|
3. |
- Ahmad, Shafqat, et al.
(author)
-
Effect of General Adiposity and Central Body Fat Distribution on the Circulating Metabolome : A Multi-Cohort Nontargeted Metabolomics Observational and Mendelian Randomization Study
- 2022
-
In: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 71:2, s. 329-339
-
Journal article (peer-reviewed)abstract
- Obesity is associated with adverse health outcomes, but the metabolic effects have not yet been fully elucidated. We aimed to investigate the association between adiposity with circulating metabolites and to address causality with Mendelian randomization (MR). Metabolomics data was generated by non-targeted ultra-performance liquid-chromatography coupled to time-of-flight mass-spectrometry in plasma and serum from three population-based Swedish cohorts: ULSAM (N=1,135), PIVUS (N=970), and TwinGene (N=2,059). We assessed associations between general adiposity measured as body mass index (BMI) and central body fat distribution measured as waist-to-hip ratio adjusted for BMI (WHRadjBMI) with 210 annotated metabolites. We employed MR analysis to assess causal effects. Lastly, we attempted to replicate the MR findings in the KORA and TwinsUK cohorts (N=7,373), the CHARGE consortium (N=8,631), the Framingham Heart Study (N=2,076) and the DIRECT consortium (N=3,029). BMI was associated with 77 metabolites, while WHRadjBMI was associated with 11 and 3 metabolites in women and men, respectively. The MR analyses in the Swedish cohorts suggested a causal association (p-value <0.05) of increased general adiposity and reduced levels of arachidonic acid, dodecanedioic acid and lysophosphatidylcholine (P-16:0) as well as with increased creatine levels. The replication effort provided support for a causal association of adiposity on reduced levels of arachidonic acid (p-value 0.03). Adiposity is associated with variation of large parts of the circulating metabolome, however causality needs further investigation in well-powered cohorts.
|
|
4. |
- Alsharari, Zayed
(author)
-
Dietary Intake, Fatty Acid Biomarkers, and Abdominal Obesity : Population-Based Observational Studies
- 2017
-
Doctoral thesis (other academic/artistic)abstract
- The aim of this thesis was to investigate the associations between fatty acid (FA) biomarkers, carbohydrate intake, and abdominal obesity (AO) and related anthropometric measures in a population-based cohort of men and women in Stockholm County. The overall hypothesis was that dietary fat quality assessed by serum and adipose tissue FA composition, and dietary intake of especially carbohydrates is associated with AO. FA composition was assessed by liquid gas chromatography, and AO was measured as waist circumference (WC), waist hip ratio (WHR) and sagittal abdominal diameter (SAD). Dietary intake was assessed by 7-day food records.Papers I, II, III, and IV were all observational studies based on a Swedish population in Stockholm County (n=5460). A sub-cohort of only men (n=301) was included in Papers II, III, and IV.In Paper I, serum proportions of the polyunsaturated FA (PUFA), linoleic acid (LA) (18:2n6), was inversely associated with AO in both men and women, whereas a positive association was observed between the saturated FA (SFA), palmitic acid (PA) (16:0) and AO measures. These findings support recent interventional studies suggesting that a higher relative intake of PUFA (LA) from vegetable oils as compared with 16:0 is associated with decreased abdominal adiposity.In Paper II, we investigated whether biomarkers of dietary fat quality were related to the corresponding FA intake from fat-rich foods reported in a short food frequency questionnaire (FFQ). Serum proportions of the long-chain n-3 PUFAs eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA) were higher among men with higher total fish intake. Serum LA was higher among men who reported a consumption of more than 5 g/d of margarine. Absolute agreement between intakes assessed with FFQ of 60YO and 7-day food record of "Kost och Metabola syndromet"/"Diet and the Metabolic syndrome" (KOMET) was highest for alcohol, total fish, and eggs. Weighted Kappa statistics revealed the strongest agreement for alcohol, margarine, and fruits.In Paper III, carbohydrate intake was inversely associated with 16:0 in serum phospholipids (PL). Disaccharide and alcohol intake was positively and non-linearly associated with palmitoleic acid (16:1) and stearoyl-CoA-desaturase (SCD) activity in PL. Alcohol was consistently associated with higher SFA and monounsaturated FA (MUFA).Results of Paper IV indicated that total carbohydrate intake was inversely associated with measures of AO and central fat distribution, WHR and SAD, respectively. Likewise, monosaccharide intake was associated with lower AO. In contrast, alcohol intake was associated with AO prevalence and all anthropometric measurements.In conclusion, serum SFA (palmitic acid) was positively associated with AO, whereas n-6 PUFA (linoleic acid) was associated with lower AO. High intake of total carbohydrate and monosaccharides were associated with lower AO. Overall, these results support a beneficial role on adiposity of diets that are higher in polyunsaturated fat (vegetable oils) and total carbohydrates compared with saturated fat.
|
|
5. |
- Bajahzer, Mohammed F., 1983-
(author)
-
Influence of dietary carbohydrates on plasma fatty acid composition : Results from interventional and observational studies
- 2024
-
Doctoral thesis (other academic/artistic)abstract
- Given reporting bias in dietary questionnaires, biomarkers offer objective assessments. Measuring circulating fatty acid (FA) composition is an established method for evaluating dietary fat quality. However, the influence of carbohydrates and sugars on plasma FA composition is less clear. This thesis investigates how carbohydrates impact circulating FAs synthesized through de novo lipogenesis (DNL). We assessed palmitate and other FAs in circulating lipids. The hypothesis was that increased dietary carbohydrate intake elevates plasma palmitate levels. In Paper I, a randomized crossover study (with all meals provided) investigated the impact of three diets varying in carbohydrate amount and type on plasma palmitate levels in healthy adults. Results showed no influence of either carbohydrate quantity or quality on plasma palmitate. However, palmitoleate increased in higher-carbohydrate diets, and carbohydrate quality affected myristate levels. In Paper II, a parallel-groups study explored the impact of high intake of sugar-sweetened soda (SS) and semi-skimmed milk (milk) on plasma palmitate among Danish adults. Both SS and milk increased palmitate in phospholipids (PL) compared with water. Excessive SS, but not milk, increased palmitoleate in all lipid fractions. In Paper III, a prospective study in Swedish children found no association between plasma palmitate in PL and incident overweight. Palmitate did not correlate with carbohydrate or sugar intake. Only stearate was associated with overweight incidence. Again, stearate was not associated with carbohydrate or sugar intake. In Paper IV, a cross-sectional study in older men found no association between serum palmitate and carbohydrate or sucrose intake, even after considering BMI or insulin sensitivity. Instead, stearate was positively associated with carbohydrate and sucrose intake, while oleate was inversely associated with sucrose and fiber intake. In conclusion, this thesis suggests that moderate changes in carbohydrate quantity or quality do not alter plasma palmitate, although overfeeding with liquid sugar causes higher palmitate in plasma PL. Stearate, but not palmitate, was linked to incident overweight in children, but none of these FAs reflected higher carbohydrate or sugar intake. Overall, palmitoleate seems to be more responsive to increased carbohydrate intake than palmitate, whereas the latter does not appear as a useful biomarker of high carbohydrate intake in Nordic populations.
|
|
6. |
- Fridén, Michael, et al.
(author)
-
Substitutions of saturated fat intakes with other macronutrients and foods and risk of NAFLD cirrhosis and all-cause hepatocellular carcinoma : a prospective cohort study
- 2024
-
In: American Journal of Clinical Nutrition. - : Elsevier. - 0002-9165 .- 1938-3207. ; 120:1, s. 187-195
-
Journal article (peer-reviewed)abstract
- BackgroundShort-term trials have shown a reduction in liver fat when saturated fatty acids (SFAs) are substituted with polyunsaturated fatty acids (PUFA), or with low-glycemic carbohydrates. However, few cohort studies have been conducted to investigate the associations of replacing SFA and SFA-rich foods with different macronutrients and foods in more severe stages of liver disease; nonalcoholic fatty liver disease (NAFLD) cirrhosis and hepatocellular carcinoma (HCC).ObjectivesTo investigate associations between the substitution of SFA and SFA-rich foods with other macronutrients and foods and NAFLD cirrhosis and HCC in a middle-aged to elderly Swedish population of n = 77,059 males and females.MethodsTime-to-event analyses were performed to investigate associations between the food and macronutrient substitutions and NAFLD cirrhosis and HCC. Multivariable Cox regression models were constructed to estimate hazard ratios (HRs) with corresponding 95% confidence intervals (CIs). Statistical isocaloric and equal-mass substitutions were performed using the leave-one-out method. Prespecified nutrient and food substitutions of interest were SFA with carbohydrates, SFA with fiber, SFA with PUFA, butter with margarine and vegetable oils, unprocessed red meat with fish, and milk with fermented milk.ResultsOver a median follow-up of 24 y, 566 cases of NAFLD cirrhosis and 205 cases of HCC were registered. Overall, dietary substitutions showed no clear associations with either NAFLD cirrhosis or HCC. Substituting SFA with carbohydrates showed an HR of 0.87 (95% CI: 0.74, 1.02) for HCC and 1.00 (95% CI: 0.89, 1.11) for NAFLD cirrhosis. Substituting milk with fermented milk showed an HR of 0.93 (95% CI: 0.85, 1.01) for HCC and 0.97 (95% CI: 0.92, 1.03) for NAFLD cirrhosis.ConclusionsNo clear associations were observed between diet and NAFLD cirrhosis or HCC. Although accompanied by low precision, possible lowered risks of HCC by substituting SFA with carbohydrates or milk with fermented milk might be of interest, but needs replication in other cohorts.
|
|
7. |
- Sabet, Julia A., 1986-, et al.
(author)
-
Feasibility and Acceptability of a Healthy Nordic Diet Intervention for the Treatment of Depression: A Randomized Controlled Pilot Trial
- 2021
-
In: Nutrients. - Basel : MDPI. - 2072-6643. ; 13
-
Journal article (peer-reviewed)abstract
- Healthy diet interventions have been shown to improve depressive symptoms, but thereis a need for randomized controlled trials (RCTs) that are double blind and investigate biologicalmechanisms. The primary objectives of this randomized controlled pilot trial were to test thepalatability of the meals and the acceptability of the intervention in preparation for an 8-week RCTin the future, which will investigate whether a healthy Nordic diet improves depressive symptomsin individuals with major depressive disorder, and associated biological mechanisms. Depressed(n = 10) and non-depressed (n = 6) women and men were randomized to receive either a healthyNordic diet (ND) or a control diet (CD) for 8 days. Participants were blinded to their diet allocationand the study hypotheses. Health questionnaires were completed before and after the interventionand, throughout the study, questionnaires assessed participants’ liking for the meals, their sensoryproperties, adherence, and open-ended feedback. In the ND group, 75% of participants consumedonly the provided foods, as instructed, compared to 50% of CD participants. The meals of both diets,on average, received good ratings for liking and sensory properties, though the ND ratings weresomewhat higher. Overall, results were positive and informative, indicating that the planned RCTwill be feasible and well-accepted, with some proposed modifications.
|
|