Fredrik Bertz
University of Gothenburg
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Fredrik Bertz.
The American Journal of Clinical Nutrition | 2016
Ena Huseinovic; Fredrik Bertz; Monica Leu Agelii; Else Hellebö Johansson; Anna Winkvist; Hilde Kristin Brekke
BACKGROUND Reproduction has been identified as an important factor for long-term weight gain among women. A previous efficacy trial has successfully produced postpartum weight loss; however, the effectiveness of this intervention needs to be established. OBJECTIVE This study was designed to evaluate the short- and long-term effectiveness of a diet behavior modification treatment to produce weight loss in postpartum women within the primary health care setting in Sweden. DESIGN During 2011-2014, 110 women with a self-reported body mass index (BMI; in kg/m(2)) of ≥27 at 6-15 wk postpartum were randomly assigned to the diet behavior modification group (D group) or the control group (C group). Women randomly assigned to the D group (n = 54) received a structured 12-wk diet behavior modification treatment by a dietitian and were instructed to gradually implement a diet plan based on the Nordic Nutrition Recommendations and to self-weigh ≥3 times/wk. Women randomly assigned to the C group (n = 56) were given a brochure on healthy eating. The primary outcome was change in body weight after 12 wk and 1 y. The retention rate was 91% and 85% at 12 wk and 1 y, respectively. RESULTS At baseline, women had a median (1st, 3rd quartile) BMI of 31.0 (28.8, 33.6), and 84% were breastfeeding. After 12 wk, median weight change in the D group was -6.1 kg (-8.4, -3.2 kg) compared with -1.6 kg (-3.5, -0.4 kg) in the C group (P < 0.001). The difference was maintained at the 1-y follow-up for the D group, -10.0 kg (-11.7, -5.9 kg) compared with -4.3 kg (-10.2, -1.0 kg) in the C group (P = 0.004). In addition, the D group reduced BMI, waist circumference, hip circumference, and body fat percentage more than did the C group at both 12 wk and 1 y (all P < 0.05). CONCLUSION A low-intensity diet treatment delivered by a dietitian within the primary health care setting can produce clinically relevant and sustainable weight loss in postpartum women with overweight and obesity. This trial was registered at clinicaltrials.gov as NCT01949558.
Journal of the Academy of Nutrition and Dietetics | 2015
Fredrik Bertz; Anna Winkvist; Hilde Kristin Brekke
The aim of this study was to evaluate dietary changes during and after a dietary treatment shown to result in significant and sustained weight loss among lactating overweight and obese women. This is crucial before clinical implementation. Data were collected from the LEVA (in Swedish: Livsstil för Effektiv Viktminskning under Amning [Lifestyle for Effective Weight Loss During Lactation]) randomized controlled factorial trial with a 12-week intervention and a 1-year follow up. At 10 to 14 weeks postpartum, 68 lactating Swedish women with a prepregnancy body mass index (calculated as kg/m(2)) of 25 to 35 were randomized to structured dietary treatment, physical exercise treatment, combined treatment, or usual care (controls) for a 12-week intervention, with a 1-year follow-up. Dietary intake was assessed with 4-day weighed dietary records. Recruitment took place between 2007 and 2010. The main outcome measures were changes in macro- and micronutrient intake from baseline to 12 weeks and 1 year. Main and interaction effects of the treatments were analyzed by a 2×2 factorial approach using a General Linear Model adjusted for relevant covariates (baseline intake and estimated underreporting). It was found that at baseline, the women had an intake of fat and sucrose above, and an intake of total carbohydrates and fiber below, recommended levels. At 12 weeks and 1 year, the dietary treatment led to reduced intake of energy (P<0.001 and P=0.005, respectively), fat (both P values <0.001), and sucrose (P<0.001 and P=0.050). At 12 weeks, total carbohydrates were reduced (P<0.001). A majority of women in all groups reported low intakes of vitamin D, folate, and/or iron. In conclusion, a novel dietary treatment led to reduced intake of fat and carbohydrates. Diet composition changed to decreased proportions of fat and sucrose, and increased proportions of complex carbohydrates, protein and fiber. Weight loss through dietary treatment was achieved with a diet in line with macronutrient recommendations.
Obesity | 2014
Ena Huseinovic; Anna Winkvist; Fredrik Bertz; Hilde Kristin Brekke
To examine changes in intake across food groups during a weight loss trial that produced significant and sustainable weight loss in lactating women receiving dietary treatment.
PLOS ONE | 2014
Hilde Kristin Brekke; Fredrik Bertz; Kathleen M. Rasmussen; Ingvar Bosaeus; Lars Ellegård; Anna Winkvist
Objective To examine the effects of Diet (D) and Exercise (E) interventions on cardiovascular fitness, waist circumference, blood lipids, glucose metabolism, inflammation markers, insulin-like growth factor 1 (IGF-1) and blood pressure in overweight and obese lactating women. Methods At 10–14 wk postpartum, 68 Swedish women with a self-reported pre-pregnancy BMI of 25–35 kg/m2 were randomized to a 12-wk behavior modification treatment with D, E, both or control using a 2×2 factorial design. The goal of D treatment was to reduce body weight by 0.5 kg/wk, accomplished by decreasing energy intake by 500 kcal/d and monitoring weight loss through self-weighing. The goal of E treatment was to perform 4 45-min walks per wk at 60–70% of max heart-rate using a heart-rate monitor. Effects were measured 12 wk and 1 y after randomization. General Linear Modeling was used to study main and interaction effects adjusted for baseline values of dependent variable. Results There was a significant main effect of the D treatment, decreasing waist circumference (P = 0.001), total cholesterol (P = 0.007), LDL-cholesterol (P = 0.003) and fasting insulin (P = 0.042), at the end of the 12-wk treatment. The decreased waist circumference (P<0.001) and insulin (P = 0.024) was sustained and HDL-cholesterol increased (P = 0.005) at the 1-y follow-up. No effects from the E treatment or any interaction effects were observed. Conclusions Dietary behavior modification that produced sustained weight loss among overweight and obese lactating women also improved risk factors for cardiovascular disease and type 2 diabetes. This intervention may not only reduce weight-related risks with future pregnancies but also long-term risk for metabolic disease. Trial registration ClinicalTrials.gov NCT01343238
European Journal of Clinical Nutrition | 2014
Ena Huseinovic; Anna Winkvist; Fredrik Bertz; H Bertéus Forslund; Hilde Kristin Brekke
BACKGROUND/OBJECTIVES:To examine associations among eating frequency, energy intake and body weight at baseline, as well as associations among change in eating frequency and change in energy intake and weight during a 12-week successful weight loss intervention in overweight and obese postpartum women.SUBJECTS/METHODS:Sixty-one Swedish women with pre-pregnancy body mass index of 25–35 kg/m2 completed a 4-day diet record at 10–14 weeks postpartum (baseline) and 12 weeks later (post-intervention), which were used to calculate energy intake and eating frequency, that is, the mean number of intake occasions per day.RESULTS:The women had a mean eating frequency of 5.9±1.2 intake occasions at baseline. A positive association was found between eating frequency and energy intake at baseline (β: 307±46 kcal, P<0.001), whereas no significant association between eating frequency and weight was observed (β: 2.3±1.2 kg, P=0.063). During the intervention period, reduced eating frequency was positively associated with energy intake reduction (β: 169±69 kcal, P=0.017) whereas no significant association was found with weight loss (β: 0.9±0.7 kg, P=0.179). Women receiving dietary intervention reduced their eating frequency more during the intervention period than did women not receiving dietary intervention (−1.0±0.7 vs −0.5±1.1, P=0.001).CONCLUSIONS:A positive association was found between eating frequency and energy intake at baseline and between reduced eating frequency and reduced energy intake during a 12-week weight loss intervention in overweight and obese postpartum women. Intervention studies on eating frequency are warranted to elucidate its effect on energy intake and weight among postpartum women.
European Journal of Clinical Nutrition | 2016
Lars Ellegård; Fredrik Bertz; Anna Winkvist; Ingvar Bosaeus; Hilde Kristin Brekke
Background/Objectives:Obesity, pregnancy and lactation all affect body composition. Simple methods to estimate body composition are useful in clinical practice and to evaluate interventions. In overweight and obese lactating women, such methods are not fully validated. The objective of this study was to validate the accuracy and precision of bioimpedance spectroscopy (BIS) by Xitron 4200 and 8-electrode multifrequency impedance (multifrequency bioimpedance analysis, MFBIA) by Tanita MC180MA with the reference methods dual energy X-ray absorptiometry (DXA) and doubly labeled water (DLW) for the assessment of body composition in 70 overweight and obese women postpartum.Subjects/Methods:The LEVA-study (Lifestyle for Effective Weight loss during lactation) consisted of an intervention and follow-up with three assessments at 3, 6 and 15 months postpartum, which made possible the validation of both accuracy and precision. Mean differences between methods were tested by a paired t-test and Bland–Altman plots for systematic bias.Results:At baseline, BIS and MFBIA underestimated fat mass (FM) by 2.6±2.8 and 8.0±4.2 kg compared with DXA (P<0.001) but without systematic bias. BIS and MFBIA overestimated total body water (TBW) by 2.4±2.2 and 4.4±3.2 kg (P<0.001) compared with DLW, with slight systematic bias by BIS. BIS correctly estimated muscle mass without systematic bias (P>0.05). BIS overestimated changes in TBW (P=0.01) without systematic bias, whereas MFBIA varied greatly and with systematic bias.Conclusions:BIS underestimates mean FM compared with DXA but can detect mean changes in body composition, although with large limits of agreement. BIS both accurately and precisely estimates muscle mass in overweight and obese women postpartum. MFBIA underestimates FM and overestimates TBW by proprietary equations compared with DXA and DLW.
Obesity | 2013
F. Slinde; Fredrik Bertz; Anna Winkvist; Lars Ellegård; H. Olausson; Hilde Kristin Brekke
To validate total energy expenditure (TEE) and activity energy expenditure (AEE) from the portable SenseWear armband (SWA) Pro 2 (TEESWA and AEESWA; InnerView software versions SWA 5.1 and SWA 6.1) against TEE from doubly labeled water (DLW) and AEE from DLW and indirect calorimetry (TEEDLW and AEEDLW) in overweight/obese lactating women at 10 weeks postpartum.
PLOS ONE | 2013
Anna Winkvist; Fredrik Bertz; Lars Ellegård; Ingvar Bosaeus; Hilde Kristin Brekke
Background Obesity and cardiovascular diseases are increasing globally and any association between reproduction and these conditions is of concern. Unfortunately, little is known about normal levels of metabolic risk factors in women of different body mass index throughout the reproductive cycle. This study is one of the first to describe the metabolic risk profile of lactating overweight or obese women at 8–12 weeks postpartum. Methods During 2007–2009, 66 overweight or obese Swedish lactating women without known diseases underwent detailed measurements of their metabolic profiles, dietary intake and general health before entering a lifestyle intervention trial. Baseline measurements took place between 8–12 wk postpartum. Almost all women were exclusively breastfeeding their term infants. Results The women were regarded as healthy, as reflected in the absence of diagnosed diseases, their own perceptions and in normal hemoglobin, albumin and fasting plasma glucose values. Four women were diagnosed with metabolic syndrome. In these cases, underlying conditions included large waist circumference, low HDL cholesterol values, high triglyceride values and relatively high blood pressure. The metabolic profile differed between overweight and obese women; obese women had significantly higher levels of fasting insulin (p = 0.017), borderline higher HOMA values (p = 0.057) and significantly higher triglyceride values (p = 0.029), as well as larger waist and hip circumferences (p<0.001 and p<0.001). However, no significant differences between overweight and obese women were detected for LDL or total cholesterol levels. Overweight and obese women reported similar total energy and macronutrient intakes, but obese women tended to be less physically active (p = 0.081). Conclusions Among generally healthy lactating women, obesity as compared to overweight is associated with increased metabolic risk. This cut-off is thus important also in the early postpartum period, and obesity among these women should warrant proper health investigation. Macronutrient intake did not differ between the groups and, hence, cannot explain these differences. Trial registration ClinicalTrials.gov Identifier: NCT01343238
Journal of Human Nutrition and Dietetics | 2016
Ena Huseinovic; Anna Winkvist; Fredrik Bertz; E. Hellebö Johansson; Hilde Kristin Brekke
BACKGROUND The present study aimed to assess dietary intake and evaluate the degree of agreement of group-level dietary intake as measured by 24-h recall against a 4-day diet record among postpartum women with overweight and obesity. METHODS A cross-sectional study was conducted of 110 Swedish women with a body mass index of ≥27 kg m(-2) at 6-15 weeks postpartum who were recruited to a weight loss trial and randomised to diet intervention or control. One 24-h recall was conducted among all women prior to randomisation. In addition, women subsequently randomised to diet intervention also conducted a 4-day diet record before receiving dietary treatment (n = 54). Paired tests were used to evaluate agreement of group-level dietary intake as measured by 24-h recall against 4-day diet record among women randomised to diet intervention. RESULTS Women reported a median (25th and 75th percentiles) energy intake of 9.1 (6.9, 11.7) MJ day(-1) and an intake of fibre, vitamin D, folate and iron below the recommended intake as assessed by 24-h recall prior to randomisation (n = 110). Group-level median intakes of energy (9.9 versus 10.0 MJ day(-1) ), fibre (21.9 versus 21.3 g day(-1) ), vitamin D (4.8 versus 6.5 μg day(-1) ), folate (296 versus 287 μg day(-1) ), iron (11.0 versus 11.3 mg day(-1) ) and calcium (915 versus 968 mg day(-1) ) did not differ significantly between the methods; however, the record captured a higher energy-adjusted intake of fat, saturated fat and alcohol, as well as a lower intake of carbohydrates, compared to the recall (n = 54). CONCLUSIONS We found no difference in group-level estimates of energy or micronutrients between the recall and the record; however, there were some differences for macronutrients.
European Journal of Clinical Nutrition | 2017
Ena Huseinovic; M Ohlin; Anna Winkvist; Fredrik Bertz; U Sonesson; Hilde Kristin Brekke
Background/Objectives:Results from studies evaluating the sustainability of diets combining environmental and nutritional aspects have been diverse; thus, greenhouse gas emissions (that is, carbon footprint (CF)) of diets in line with dietary recommendations in free-living individuals warrants further examination. Here, changes in dietary CF related to changes in food choice during a weight loss trial among lactating women who received a 12-week diet intervention based on the Nordic Nutrition Recommendations (NNR) 2004 were analyzed. The objective of this study was to examine if a diet intervention based on NNR 2004 results in reduced dietary CF.Subjects/Methods:Changes in dietary CF were analyzed among 61 lactating women participating in a weight loss trial. Food intake data from 4-day weighed diet records and results from life cycle analyses were used to examine changes in dietary CF across eight food groups during the intervention, specified in the unit carbon dioxide equivalent (CO2eq/day). Differences in changes in dietary CF between women receiving diet treatment (D-group) and women not receiving it (ND-group) were compared.Results:There was no difference in change in dietary CF of the overall diet between D- and ND-group (P>0.05). As for the eight food groups, D-group increased their dietary CF from fruit and vegetables (+0.06±0.13 kg CO2eq/day) compared with a decrease in ND-group (−0.01±0.01 kg CO2eq/day) during the intervention, P=0.01.Conclusions:A diet intervention in line with NNR 2004 produced clinically relevant weight loss, but did not reduce dietary CF among lactating women with overweight and obesity. Dietary interventions especially designed to decrease dietary CF and their coherence with dietary recommendations need further exploration.