Petter Fagerberg

Mr. Petter Fagerberg

Karolinska Institutet, Stockholm, Sweden
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2018 in International Journal of Sport Nutrition and Exercise Metabolism
Verified
Journal Article
Closed access
Petter FagerbergPetter Fagerberg
Petter Fagerberg
Energy availability (EA) is a scientific concept describing how much energy is available for basic metabolic functions such as reproduction, immunity, and skeletal homeostasis. Carefully controlled studies on women have shown pathological effects of EA < 30 kcal/kg fat-free mass (FFM), and this state has been labeled low EA (LEA). Bodybuilding is a sport in which athletes compete to show muscular definition, symmetry, and low body fat (BF). The process of contest preparation in bodybuilding includes months of underfeeding, thus increasing the risk of LEA and its negative health consequences. As no well-controlled studies have been conducted in natural male bodybuilders on effects of LEA, the aim of this review was to summarize what can be extrapolated from previous relevant research findings in which EA can be calculated. The reviewed literature indicates that a prolonged EA < 25 kcal/kg FFM results in muscle loss, hormonal imbalances, psychological problems, and negatively affects the cardiovascular system when approaching the lower limits of BF (∼4%–5%) among males. Case studies on natural male bodybuilders who prepare for contest show muscle loss (>40% of total weight loss) with EA < 20 kcal/kg FFM, and in the study with the lowest observed BF (∼4 kg), major mood disturbance and hormonal imbalances co-occurred. Studies also underline the problem of BF overshoot during refeeding after extremes of LEA among males. A more tempered approach (EA > 25 kcal/kg FFM) might result in less muscle loss among natural male bodybuilders who prepare for contest, but more research is needed.

21 December 2019 in BMC Public Health
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Journal Article
Open access
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Petter FagerbergPetter Fagerberg
Petter Fagerberg
BLBilly Langlet§
Billy Langlet§
AOAleksandra Oravsky
Aleksandra Oravsky
JSJohanna Sandborg
Johanna Sandborg
MLMarie Löf
Marie Löf
IIIoannis Ioakimidis
Ioannis Ioakimidis
Background: Ultra-processed food consumption is a risk factor for obesity and has a negative environmental impact. Food companies spend billions of dollars on advertisements each year to increase the consumption of ultra-processed food. In Australia, USA, and New Zealand, most food advertisements around schools and in train stations promote ultra-processed food, but no similar studies have been conducted in Sweden. The aim of this study was to explore the proportion of ultra-processed food advertisements in two districts of Stockholm, Sweden with low vs. high socioeconomic status (SES). Methods: Two independent researchers (per area) mapped all advertisements, including storefronts, in two Stockholm districts. During consecutive days, all advertisements were photographed in Skärholmen (low SES district), and Östermalmstorg (high SES district), on the streets inside and outside the subway stations, as well as inside and outside of local shopping malls. Advertisements promoting food products were identified and a trained dietician categorized whether they promoted ultra-processed foods. Chi-Square test was conducted to test for differences in the proportion of ultra-processed food advertisements between the two study areas. Results: In total, 4092 advertisements were photographed in Skärholmen (n = 1935) and Östermalm (n = 2157). 32.8% of all advertisements promoted food, while 65.4% of food advertisements promoted ultra-processed foods. A significantly higher proportion of ultra-processed food advertisements out of total food advertisements was identified in the low SES area, irrespective of the researcher taking the pictures (74.6% vs. 61.8%, p < 0.001 and 70.4% vs. 54.8%, p = 0.001). There was no significant difference in the proportion of food advertisements out of total advertisements between the two areas. Conclusions: This study provides initial evidence about the scale and the differences in exposure to food advertisements across areas in Stockholm. The observed high proportion of ultra-processed food advertisements is concerning and is in sharp contrast to the Swedish dietary guidelines that recommend reduced consumption of such foods. Based on our results, residents in low SES areas might be more exposed to ultra-processed food advertisements than those in high SES areas in Stockholm. If such findings are confirmed in additional areas, they should be considered during the deployment of food advertisement regulatory actions.

9 March 2021 in Nutrients
Verified
Journal Article
Open access
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Petter FagerbergPetter Fagerberg
Petter Fagerberg
Evangelia CharmandariEvangelia Charmandari
Evangelia Charmandari
Christos DiouChristos Diou
Christos Diou
RHRachel Heimeier
Rachel Heimeier
YKYoula Karavidopoulou
Youla Karavidopoulou
IIIoannis Ioakimidis
Ioannis Ioakimidis
Fast self-reported eating rate (SRER) has been associated with increased adiposity in children and adults. No studies have been conducted among high-school students, and SRER has not been validated vs. objective eating rate (OBER) in such populations. The objectives were to investigate (among high-school student populations) the association between OBER and BMI z-scores (BMIz), the validity of SRER vs. OBER, and potential differences in BMIz between SRER categories. Three studies were conducted. Study 1 included 116 Swedish students (mean ± SD age: 16.5 ± 0.8, 59% females) who were eating school lunch. Food intake and meal duration were objectively recorded, and OBER was calculated. Additionally, students provided SRER. Study 2 included students (n = 50, mean ± SD age: 16.7 ± 0.6, 58% females) from Study 1 who ate another objectively recorded school lunch. Study 3 included 1832 high-school students (mean ± SD age: 15.8 ± 0.9, 51% females) from Sweden (n = 748) and Greece (n = 1084) who provided SRER. In Study 1, students with BMIz ≥ 0 had faster OBER vs. students with BMIz < 0 (mean difference: +7.7 g/min or +27%, p = 0.012), while students with fast SRER had higher OBER vs. students with slow SRER (mean difference: +13.7 g/min or +56%, p = 0.001). However, there was “minimal” agreement between SRER and OBER categories (κ = 0.31, p < 0.001). In Study 2, OBER during lunch 1 had a “large” correlation with OBER during lunch 2 (r = 0.75, p < 0.001). In Study 3, fast SRER students had higher BMIz vs. slow SRER students (mean difference: 0.37, p < 0.001). Similar observations were found among both Swedish and Greek students. For the first time in high-school students, we confirm the association between fast eating and increased adiposity. Our validation analysis suggests that SRER could be used as a proxy for OBER in studies with large sample sizes on a group level. With smaller samples, OBER should be used instead. To assess eating rate on an individual level, OBER can be used while SRER should be avoided.

21 July 2020 in JMIR mHealth and uHealth
Verified
Journal Article
Open access
BLBilly Langlet§
Billy Langlet§
CMChristos Maramis
Christos Maramis
Christos DiouChristos Diou
Christos Diou
Nicos MaglaverasNicos Maglaveras
Nicos Maglaveras
Petter FagerbergPetter Fagerberg
Petter Fagerberg
IIIoannis Ioakimidis
Ioannis Ioakimidis
Background: Obesity interventions face the problem of weight regain after treatment as a result of low compliance. Mobile health (mHealth) technologies could potentially increase compliance and aid both health care providers and patients. Objective: This study aimed to evaluate the acceptability and usability and define system constraints of an mHealth system used to monitor dietary habits of adolescents in real life, as a first step in the development of a self-monitoring and lifestyle management system against adolescent obesity. Methods: We recruited 26 students from a high school in Stockholm, Sweden. After a 30-minute information meeting and 5-minute individual instruction on how to use an mHealth system (smartphone with app and two external sensors), participants used it for 2-3 weeks to objectively collect dietary habits. The app and sensors were used by the participants, without supervision, to record as many main meals and snacks as possible in real life. Feasibility was assessed following the “mHealth evidence reporting and assessment checklist,” and usability was assessed by questionnaires. Compliance was estimated based on system use, where a registration frequency of 3 main meals (breakfast, lunch, and dinner) per day for the period of the experiment, constituted 100% compliance. Results: Participants included in the analysis had a mean age of 16.8 years (SD 0.7 years) and BMI of 21.9 kg/m2 (SD 4.1 kg/m2). Due to deviations from study instructions, 2 participants were excluded from the analysis. During the study, 6 participants required additional information on system use. The system received a ‘Good’ grade (77.1 of 100 points) on the System Usability Scale, with most participants reporting that they were comfortable using the smartphone app. Participants expressed a willingness to use the app mostly at home, but also at school; most of their improvement suggestions concerned design choices for the app. Of all main meals, the registration frequency increased from 70% the first week to 76% the second week. Participants reported that 40% of the registered meals were home-prepared, while 34% of the reported drinks contained sugar. On average, breakfasts took place at 8:30 AM (from 5:00 AM to 2:00 PM), lunches took place at 12:15 PM (from 10:15 AM to 6:15 PM), and dinners took place at 7:30 PM (from 3:00 PM to 11:45 PM). When comparing meal occurrence during weekdays vs weekends, breakfasts and lunches were eaten 3 hours later during weekends, while dinner timing was unaffected. Conclusions: From an infrastructural and functional perspective, system use was feasible in the current context. The smartphone app appears to have high acceptability and usability in high school students, which are the intended end-users. The system appears promising as a relatively low-effort method to provide real-life dietary habit measurements associated with overweight and obesity risk.

16 July 2020 in Nutrients
Verified
Journal Article
Open access
PDF file
Petter FagerbergPetter Fagerberg
Petter Fagerberg
LKLisa Klingelhoefer
Lisa Klingelhoefer
MBMatteo Bottai
Matteo Bottai
BLBilly Langlet§
Billy Langlet§
KKKonstantinos Kyritsis
Konstantinos Kyritsis
IIIoannis Ioakimidis
Ioannis Ioakimidis
Unintentional weight loss has been observed among Parkinson’s disease (PD) patients. Changes in energy intake (EI) and eating behavior, potentially caused by fine motor dysfunction and eating-related symptoms, might contribute to this. The primary aim of this study was to investigate differences in objectively measured EI between groups of healthy controls (HC), early (ESPD) and advanced stage PD patients (ASPD) during a standardized lunch in a clinical setting. The secondary aim was to identify clinical features and eating behavior abnormalities that explain EI differences. All participants (n = 23 HC, n = 20 ESPD, and n = 21 ASPD) went through clinical evaluations and were eating a standardized meal (200 g sausages, 400 g potato salad, 200 g apple purée and 500 mL water) in front of two video cameras. Participants ate freely, and the food was weighed pre- and post-meal to calculate EI (kcal). Multiple linear regression was used to explain group differences in EI. ASPD had a significantly lower EI vs. HC (−162 kcal, p < 0.05) and vs. ESPD (−203 kcal, p < 0.01) when controlling for sex. The number of spoonfuls, eating problems, dysphagia and upper extremity tremor could explain most (86%) of the lower EI vs. HC, while the first three could explain ~50% vs. ESPD. Food component intake analysis revealed significantly lower potato salad and sausage intakes among ASPD vs. both HC and ESPD, while water intake was lower vs. HC. EI is an important clinical target for PD patients with an increased risk of weight loss. Our results suggest that interventions targeting upper extremity tremor, spoonfuls, dysphagia and eating problems might be clinically useful in the prevention of unintentional weight loss in PD. Since EI was lower in ASPD, EI might be a useful marker of disease progression in PD.

8 July 2018 in Nutrients
Verified
Journal Article
Open access
PDF file
BLBilly Langlet§
Billy Langlet§
MBMona Tang Bach
Mona Tang Bach
DODorothy Odegi
Dorothy Odegi
Petter FagerbergPetter Fagerberg
Petter Fagerberg
IIIoannis Ioakimidis
Ioannis Ioakimidis
Manipulating food properties and serving environment during a meal can significantly change food intake at group level. However, the evaluation of the usefulness of such manipulations requires an understanding of individual behavioural changes. Three studies were conducted to explore the effect of unit size and meal occasion on eating behaviour characteristics (food intake, meal duration, number of bites and chews). All studies used a randomised crossover design, with a one-week wash-out period, starting with a familiarisation meal, with the participation of healthy, normal weight females between the ages of 18–35 years. In Study 1 (n = 19) three cube sizes (0.5, 1.0 and 1.5 cm3) of vegetable hash and chicken were compared. In Study 2 (n = 18) mashed potatoes and mincemeat were compared to whole potatoes and meatballs. In Study 3 (n = 29) meals served at lunch time (11:00–13:00) were compared to identical meals served at dinner time (17:00–19:00). The largest food unit size lead to significantly increased meal duration in Study 2 (mean difference 0.9 min, 95% confidence interval (CI) 0.0–1.8), but not in Study 1 (mean difference 1 min, 95% CI 0.1–2.0). There was a significant increase in number of chews in the large unit size condition of both Study 1 (mean difference 88, 95% CI 12–158) and Study 2 (mean difference 95, 95% CI 12–179). Different serving occasions did not significantly change any of the eating behaviours measured. Except for number of bites in Study 2 (R2 = 0.60), most individuals maintained their eating behaviour relative to the group across unit sizes and serving occasions conditions (R2 > 0.75), which suggests single meal testing can provide information about the behavioural characteristics of individual eating styles under different conditions.