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. 2022 Aug 31;30(10):1963–1972. doi: 10.1002/oby.23535

Changes in hedonic hunger and food reward after a similar weight loss induced by a very low‐energy diet or bariatric surgery

Marthe Isaksen Aukan 1,2,✉, Ingrid Øfsti Brandsæter 1, Silje Skårvold 1, Graham Finlayson 3, Siren Nymo 1,2,4, Silvia Coutinho 1,5, Catia Martins 1,2,6
PMCID: PMC9804643  PMID: 36046953

Abstract

Objective

The aim of this study was to compare changes in hedonic hunger and food reward in individuals with severe obesity achieving 10% to 15% weight loss with a very low‐energy diet (VLED) alone or VLED and bariatric surgery.

Methods

Patients scheduled for sleeve gastrectomy (SG) or Roux‐en‐Y gastric bypass (RYGB) initiated a VLED 2 weeks prior to surgery and continued the diet for 8 weeks postoperatively. BMI‐matched controls underwent a VLED for 10 weeks. Hedonic hunger was assessed with the Power of Food Scale, and food reward with the Leeds Food Preference Questionnaire, pre and post intervention.

Results

A total of 44 participants completed the study: 15 SG, 14 RYGB, and 15 controls (61%, 79% and 69% females, respectively; BMI: 40.5 ± 0.5 kg/m2; age: 43.9 ± 1.4 years). Average weight loss was 18.3 ± 0.6 kg (16%), comprising 13.5 ± 0.5 kg fat mass, with no significant differences between groups. Similar reductions in hedonic hunger were observed in all groups. Overall, food reward was similarly reduced in SG and RYGB groups, whereas controls showed little or no change.

Conclusions

Independent of modality, weight loss seems to reduce hedonic hunger, but bariatric surgery leads to several additional favorable changes in food reward and preferences.

Study Importance.

What is already known?

  • Hedonic appetite can easily override homeostatic signals.

  • Individuals with obesity have a greater hedonic appetite compared with individuals without obesity.

  • Following bariatric surgery, patients experience decreased hedonic eating behavior and improved appetite control, but the effect of weight loss induced by dietary restriction alone is unclear.

What does this study add?

  • Hedonic hunger decreases regardless of weight loss modality when weight loss is matched.

  • However, bariatric surgery is superior compared with dietary restriction alone on the effect of food reward.

How might these results change the direction of research or the focus of clinical practice?

  • Comprehensive behavioral interventions might be needed to control hedonic hunger and food reward after weight loss with dietary restriction alone.

  • Future research should investigate potential relationships between hedonic hunger and food reward and long‐term weight loss maintenance after both lifestyle treatment and bariatric surgery.

INTRODUCTION

Lifestyle treatments of obesity have had limited success. Even though most individuals with obesity can achieve a clinically significant weight loss (5%–10% of initial body weight), the majority experience weight regain and some relapse to or above baseline weight [1]. To date, bariatric surgery is the most effective treatment, leading to sustained lower body weight in the long term, which is not yet achievable with conservative approaches [2]. The mechanisms behind the long‐term weight loss success after bariatric surgery are still not clearly understood, but beneficial changes in appetite behavior are seen [3].

Appetite behavior is highly complex, and the brain plays a key role controlling energy intake. Homeostatic brain regions, mainly the hypothalamus, receive information from the periphery regarding both acute and chronic nutritional status and adjust appetite accordingly in order to maintain homeostasis [4]. However, advances in research have led to the integration of hedonic brain regions in appetite control [5]. Hedonic hunger refers to appetite for palatable foods and is driven by external sensory information, feelings, and emotions [6]. Food reward can be characterized by “liking” (pleasurable response to food) and “wanting” (motivation to eat palatable foods that provided pleasure in the past) [7]. Exposure to palatable foods trigger dopamine release and is associated with wanting for food [8]. Thus, the hedonic system can operate independently of homeostatic signals when food is highly palatable and easily available [9]. Moreover, individuals with obesity have shown greater food reinforcement [10] and hedonic hunger [11], stronger liking for sweetness [12], and higher wanting for food [13], compared with individuals without obesity. Higher sensitivity to food reward and food reinforcement has also been associated with greater energy intake [14]. This might compromise adherence to dietary interventions.

Even though an increased drive to eat is commonly seen following diet‐induced weight loss [15, 16], food reward has been described to decrease following different lifestyle interventions [17]. Following sleeve gastrectomy (SG) and Roux‐en‐Y gastric bypass (RYGB), patients experience decreases in measures of hedonic eating, lower preference for energy dense foods [11, 18, 19, 20, 21, 22, 23, 24], development of an aversion to sweetness [25, 26], lower frequency of food cravings, and decreased influence of emotions and external food cues on food intake [22, 25]. However, knowledge on the effect of dietary restriction alone on hedonic hunger is limited, and no studies have compared diet alone with bariatric surgery. Moreover, it remains to be elucidated whether the beneficial effects of bariatric surgery on hedonic hunger and food reward are mediated by the bariatric procedure, weight loss, the inherent changes in the diet, or a combination of those.

Therefore, we aimed to compare how a similar weight loss achieved by a very low‐energy diet (VLED) alone or VLED in combination with one of the two most performed bariatric procedures (SG and RYGB) impacts hedonic hunger and food reward in individuals with severe obesity.

METHODS

The effect of DIet‐induced weight loss versus Sleeve gastrectomy and Gastric bypass on APpetite (DISGAP) study is a three‐armed prospective nonrandomized controlled trial, comparing how a similar weight loss induced by diet or bariatric surgery impacts homeostatic and hedonic appetite markers and gut microbiota, both in the short and long term. The present paper reports the initial changes in hedonic hunger and food reward after a similar weight loss induced by diet alone, diet plus SG, or diet + RYGB. An outline of the present study can be seen in Figure 1.

FIGURE 1.

FIGURE 1

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Study design. BL, baseline; PA, physical activity; RYGB, Roux‐en‐Y gastric bypass; SG, sleeve gastrectomy; VLED, very low‐energy diet; W11, week 11; WL, weight loss [Color figure can be viewed at wileyonlinelibrary.com]

Adults with severe obesity scheduled for SG or RYGB at two local hospitals in the Central Norway Health Region were recruited. The control group (VLED intervention alone) was composed of patients on a waiting list for bariatric surgery and patients who declined or were not eligible for surgery, as well as individuals from the local community (advertised at St. Olav's and the Norwegian University of Science and Technology [NTNU] intranet). The control group was matched for preoperative body mass index (BMI), age, and sex of the surgical groups. Recruitment and data collection took place between September 2019 and January 2022. A flowchart of the study can be seen in Figure 2. The study was approved by the regional ethics committee (REK 2019/252), registered in ClinicalTrials.gov (NCT04051190), and conducted according to the guidelines laid down in the Declaration of Helsinki. All participants provided written informed consent before enrollment in the study.

FIGURE 2.

FIGURE 2

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Flow diagram of the study. RYGB, Roux‐en‐Y gastric bypass; SG, sleeve gastrectomy [Color figure can be viewed at wileyonlinelibrary.com]

Participants had to be weight stable (self‐reported) (< 2‐kg body weight change over the last 3 months) and not enrolled in any other obesity treatment or behavioral program. Patients who had previously undergone bariatric surgery, who used medication known to affect energy metabolism or appetite, and who had a current cancer diagnosis or substance abuse, as well as those presenting with a psychiatric diagnosis that precluded bariatric surgery (such as eating disorders), were excluded from the study.

Bariatric surgeries were performed at St. Olav University Hospital in Trondheim and the Namsos Hospital, both in Norway, using standard laparoscopic procedures. The SG involved dividing the gastrocolic ligament, initiating the gastrectomy 4 cm proximal to the pylorus along the greater curvature, and creating the sleeve along the lesser curvature using a 36 French Bougie. The RYGB procedure involved creating a small (~20–30 mL) proximal gastric pouch and a stapled gastrojejunostomy. A 75– to 150‐cm Roux‐Y limb was constructed by transecting the jejunum 60 to 100 cm distal to the ligament of Treitz and performing a stapled jejunostomy at this site.

Participants from all groups were asked to follow a formula‐based VLED using a variety of commercial food packs (Lighter Life) composed of different soups, shakes, pasta dishes, bars, and porridge for 10 weeks under the guidance of a registered dietitian. The average daily nutritional composition of the VLED used in this study was 750 kcal; energy percentages (E%) were 26 E% fat, 36 E% carbohydrates, 5 E% fiber, and 33 E% protein. In addition, participants were encouraged to consume a maximum of 100 g of low‐starch vegetables per day, as well as 2.5 L of water daily. Alcohol consumption was not allowed during the 10‐week intervention. Noncaloric beverages were allowed, and a maximum of 500 mL of low‐energy drinks (<3 kcal/100 mL) and four sugar−/calorie‐free chewing gum, artificial sweeteners, or mints per day. Patients scheduled for bariatric surgery initiated the diet 2 weeks prior to surgery as standard procedure and continued the VLED for another 8 weeks postoperatively. The first weeks after surgery, SG and RYGB patients were instructed to consume only fluids (food packs in liquid form as soups and shakes) and then gradually increase the texture of the commercial food packs provided. All participants were asked to fill out a self‐reported food diary. At weekly follow‐ups, food diaries were discussed, side effects recorded, body weight monitored, and ketone bodies (acetoacetate) measured in urine with ketostix (Bayer Ketostix 2880 Urine Reagent Test Strip, Ascensia Diabetes Care), as a measure of dietary compliance. The plasma concentration of beta‐hydroxybutyric acid (ßHB), another ketone body, was also measured pre and post intervention as an additional measure of compliance (MAK134, Sigma‐Aldrich). Because of COVID‐19 restrictions, most participants were followed up by phone.

Participants were asked to maintain their physical activity (PA) level during the 10‐week intervention. Compliance with this recommendation was assessed by asking participants to wear SenseWear armbands (BodyMedia) for 7 days prior to baseline (BL) and at week 10. The data were considered valid if participants wore the device for ≥ 4 days, including at least one weekend day, for more than 95% (22.8 h/d) of the time [27]. The following variables were analyzed: average daily steps, PA level, metabolic equivalents (METs), and total PA duration.

After an overnight fast (at least 10 hours) at BL and week 11 (W11), air‐displacement plethysmography (BodPod, COSMED) was used to measure body weight, fat mass, and fat‐free mass. The test meal consisted of a 200‐mL commercial low‐glycemic drink (Diben Drink, Fresenius Kabi Norge AS) (300 kcal, 42 E% fat, 35 E% carbohydrates, 3 E% fiber, and 20 E% protein), which was consumed slowly over a 15‐minute period, to avoid dumping syndrome.

Hedonic hunger was assessed by the Power of Food Scale (PFS) [28]. This questionnaire consists of 15 questions, comprising an aggregated score and divided into three subcategories: “food available,” readily attainable food, but not physically present; “food present,” the food both available and physically present, but not tasted; and “food tasted,” food physically present and tasted or about to be tasted. A Likert scale with five levels was used (1 = “I don't agree at all” to 5 = “I strongly agree”). The higher the PFS score, the higher the hedonic hunger. The questionnaire was handed out 60 minutes after initiating the breakfast.

Food preferences and reward were assessed using the Leeds Food Preference Questionnaire (LFPQ) [29]. The LFPQ is a computerized behavioral task that provides measures of “explicit liking” and “explicit and implicit wanting” using images of food. The food pictures in the LFPQ are divided into four categories: high‐fat and sweet (HFSW), low‐fat and sweet (LFSW), high‐fat and savory (HFSA), and low‐fat and savory (LFSA). For this study, participants were presented with pictures of foods common in the Norwegian diet. Individual food images were randomly presented to the participants who were required to rate them according to “How pleasant would it be to taste some of this food now?” (explicit liking) and “How much do you want some of this food now?” (explicit wanting) with the scale ranging from “not at all” to “extremely.” Next, a forced choice task presented participants with a series of food image pairs and the instruction “Which food do you most want to eat now?” A score was calculated according to how often a food category was chosen over another category, how often it was not selected, and the reaction time of the trial (implicit wanting). The LFPQ was performed in the fasted state and immediately after breakfast.

This paper reports a secondary analysis of the main study powered to detect differences in postprandial plasma concentrations of glucagon‐like peptide‐1 (GLP‐1) between groups. Power calculation was performed assuming that bariatric surgery would induce a postprandial increase in GLP‐1 that was two (SG) and three times (RYGB) larger compared with diet‐induced weight loss. For a power of 80% and 0.05 significance level and assuming an SD of 1000 min*pmol/L and a within group variance of 640,000 min*pmol/L [30], 45 participants would be required (15 in each group).

Statistical analysis was carried out using SPSS Statistics version 27 (IBM Corp.). Data are presented as mean ± SEM, unless otherwise stated. Because of the large number of tests, the significance level was reduced to p < 0.01 to avoid type I errors. Residuals were checked and they did not deviate significantly from normality. All data were analyzed using a linear mixed‐effects model with restricted maximum likelihood estimation, including fixed effects for group, time, and their interaction. Bonferroni correction was used for post hoc pairwise comparisons.

RESULTS

Table 1 shows anthropometrics at BL and W11. Forty‐four participants completed BL and W11 assessments (n = 15 VLED, n = 15 SG, and n = 14 RYGB). There were no significant differences in any anthropometric variables between groups at either time point. Overall, participants lost 18.3 ± 0.6 kg (~16%) from BL to W11. BMI dropped by 6.3 ± 0.8 kg/m2, fat mass decreased by 13.5 ± 0.5 kg (24% change), and fat‐free mass decreased by 4.8 ± 0.3 kg (8% change) (p < 0.001, for all). Participants were not ketotic at baseline (ßHB plasma concentration: 0.1 ± 0.07 mM), but all were in nutritional‐induced ketosis at W11 (ßHB plasma concentration: 0.7 ± 0.07 mM), with no differences between groups. No significant differences between groups or changes over time were seen for any of the PA variables assessed (data not shown).

TABLE 1.

Mean characteristics of the participants at baseline and week 11

Baseline Week 11
Control SG RYGB Control SG RYGB
n 15 15 14
Age 45.5 ± 2.6 39.6 ± 2.4 46.7 ± 2.5
Females, % 69 79 61
Body weight (kg) 115.4 ± 3.9a 117.6 ± 3.6b 120.4 ± 3.7c 98.1 ± 3.9a 98.6 ± 3.6b 101.6 ± 3.7c
Weight loss (kg) −17.3 ± 1.0 −19.0 ± 1.0 −18.8 ± 1.0
BMI (kg/m2) 39.7 ± 0.9a 40.2 ± 0.7b 41.6 ± 1.1c 33.7 ± 0.9a 34.1 ± 0.8b 35.0 ± 1.3 c
FM (%) 46.6 ± 1.5a 47.9 ± 1.4b 47.0 ± 1.4c 41.0 ± 1.5a 43.0 ± 1.4b 42.7 ± 1.4c
FM (kg) 53.7 ± 2.6a 56.5 ± 2.4b 56.5 ± 2.4c 40.4 ± 2.6a 42.4 ± 2.4b 43.6 ± 2.4c
FFM (%) 53.0 ± 1.5a 52.1 ± 1.4b 53.0 ± 1.4c 59.1 ± 1.5a 57.0 ± 1.4b 57.3 ± 1.4c
FFM (kg) 61.7 ± 2.6a 61.1 ± 2.4b 63.8 ± 2.4c 57.8 ± 2.5a 56.2 ± 2.4b 58.1 ± 2.4c
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Note: Data presented as estimated marginal mean ± SEM. Mean values sharing the same superscript letter denote significant changes over time (p < 0.001 for all).

Abbreviations: FFM, fat‐free mass; FM, fat mass; RYGB, Roux‐en‐Y gastric bypass; SG, sleeve gastrectomy.

Hedonic hunger

Mean scores of the PFS can be seen in Figure 3A–D. At baseline, no differences were seen between groups, but there was a tendency for the control group to have a higher aggregated score compared with RYGB (p = 0.024). All groups experienced similar reductions in the aggregated score over time (p = 0.001, p < 0.001, and p = 0.003, for controls, SG, and RYGB, respectively). There was a decrease in the subcategory “food available” in controls and SG (p = 0.003 and p < 0.001, respectively) and a tendency toward a decrease in RYGB (p = 0.013). For the category “food present,” all groups experienced similar reductions from baseline to W11 (p = 0.002, p < 0.001, and p < 0.001, for controls, SG and RYGB, respectively). There was an overall reduction in the category “food tasted” from baseline to W11 but this was not significant at group level.

FIGURE 3.

FIGURE 3

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Power of Food Scale scores. Data presented as mean ± SE. Asterisks denote significant differences over time (***p < 0.001, **p < 0.01) BL, baseline; RYGB, Roux‐en Y gastric bypass; SG, sleeve gastrectomy; W11, week 11

Table 2 presents mean scores from the LFPQ.

TABLE 2.

Mean scores from the Leeds Food Preference Questionnaire

Baseline Week 11
Control SG RYGB Control SG RYGB
Explicit liking
Fasting HFSA 48.7 ± 5.7 39.4 ± 5.3 33.8 ± 5.4 43.9 ± 5.2 25.9 ± 5.2 28.1 ± 5.4
LFSA 52.9 ± 5.6 43.6 ± 5.1 43.5 ± 5.3 57.9 ± 5.2 36.1 ± 5.2 41.4 ± 5.4
HFSW 43.6 ± 5.8* 34.1 ± 5.3b 17.4 ± 5.5* 32.9 ± 4.3 16.8 ± 4.3b 12.7 ± 4.3
LFSW 52.3 ± 5.5 47.4 ± 5.1 47.5 ± 5.2 51.8 ± 4.8 39.9 ± 4.8 45.0 ± 4.9
Postprandial HFSA 43.5 ± 5.7 40.1 ± 5.3b 23.4 ± 5.4c 30.4 ± 5.2* 14.8 ± 5.2b 2.3 ± 5.4c*
LFSA 43.5 ± 5.6 31.5 ± 5.1 28.5 ± 5.3c 35.3 ± 5.2* 16.2 ± 5.2 5.7 ± 5.4c*
HFSW 35.9 ± 5.8 32.5 ± 5.3b 17.6 ± 5.5c 21.3 ± 4.3 7.7 ± 4.3b 1.8 ± 4.3c
LFSW 48.1 ± 5.5 43.8 ± 5.1b 38.2 ± 5.2c 37.8 ± 4.8* 22.3 ± 4.8b 7.2 ± 4.9c*
Implicit wanting
Fasting HFSA 12.1 ± 5.8 1.0 ± 5.3 −0.5 ± 5.4 5.8 ± 4.8 1.2 ± 4.8 −1.5 ± 4.9
LFSA −5.1 ± 7.9a −5.5 ± 7.3 4.9 ± 7.5 16.5 ± 7.3a 0.4 ± 7.2 15.7 ± 6.9
HFSW −11.0 ± 6.9a −11.4 ± 6.4 −23.9 ± 6.5 −34.0 ± 5.6a −24.5 ± 5.6 −38.6 ± 5.8
LFSW 4.1 ± 4.5 15.9 ± 4.1 19.4 ± 4.2 11.7 ± 4.6 23.1 ± 4.6 24.4 ± 4.7
Postprandial HFSA 9.6 ± 5.8 2.5 ± 5.3 0.7 ± 5.4 2.3 ± 4.8 7.2 ± 4.8 0.2 ± 4.9
LFSA −9.9 ± 7.9a −5.7 ± 7.3 −1.8 ± 7.5 8.2 ± 7.3a −2.8 ± 7.2 6.9 ± 7.5
HFSW −10.8 ± 6.9a −12.7 ± 6.3b −24.7 ± 6.5 −28.9 ± 5.6a −27.9 ± 5.6b −38.8 ± 5.8
LFSW 11.2 ± 4.5 16.0 ± 4.1 25.8 ± 4.2 18.5 ± 4.6 23.6 ± 4.6 31.8 ± 4.8
Explicit wanting
Fasting HFSA 49.2 ± 5.6 38.7 ± 5.1b 33.9 ± 5.3 44.8 ± 5.1 23.2 ± 5.1b 23.7 ± 5.3
LFSA 53.5 ± 5.4 42.4 ± 4.9 42.4 ± 5.1 56.4 ± 5.4 35.5 ± 5.4 40.7 ± 5.5
HFSW 44.6 ± 5.4* 33.4 ± 4.9b 17.4 ± 5.1* 32.0 ± 4.1 15.5 ± 4.1b 12.1 ± 4.3
LFSW 52.9 ± 5.4 47.9 ± 4.9 45.3 ± 5.1 52.6 ± 5.0 38.8 ± 5.0 44.1 ± 5.2
Postprandial HFSA 42.6 ± 5.6 36.1 ± 5.1b 22.7 ± 5.3c 26.4 ± 5.1* 14.3 ± 5.1b 2.7 ± 5.2c*
LFSA 44.2 ± 5.4 30.7 ± 4.9 30.6 ± 5.1c 38.2 ± 5.4*# 16.5 ± 5.4* 5.7 ± 5.4c#
HFSW 36.4 ± 5.4a* 28.6 ± 4.9b 15.5 ± 5.1c* 19.9 ± 4.1a 7.1 ± 4.1b 1.7 ± 4.2c
LFSW 46.6 ± 5.4 40.1 ± 4.9b 40.0 ± 5.1c 35.9 ± 5.0* 22.2 ± 5.0b 6.5 ± 5.2c*
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Note: Data presented as estimated marginal mean ± SEM. Averages sharing the same superscript letter denote a significant change over time (p < 0.01). Averages sharing the same superscript symbol denote significant differences between groups (*#, p < 0.01).

Abbreviations: HFSA, high‐fat savory; HFSW, high‐fat sweet; LFSA, low‐fat savory; LFSW, low‐fat sweet; RYGB, Roux‐en Y gastric bypass; SG, sleeve gastrectomy.

Explicit liking

At BL, controls had greater fasting HFSW compared with RYGB (p = 0.003) (Table 2). SG experienced reductions in fasting for HFSW from BL to W11 (p = 0.004). Overall, there was a reduction over time for postprandial liking for all food categories but not at the group level. HFSA was reduced for SG and RYGB (p < 0.001 for both). At W11, controls had greater postprandial liking for HFSA compared with RYGB (p = 0.001). Postprandial LFSA decreased only for RYGB (p = 0.001), and scores were lower compared with controls (p < 0.001). Postprandial HFSW and LFSW were reduced for SG and RYGB (p = 0.001 and p < 0.001, respectively). At W11, RYGB had lower liking for LFSW compared with controls (p < 0.001).

Implicit wanting

For LFSA, there was an overall increase, but this was significant only for the control group (p < 0.001, both fasting and postprandially). Overall, implicit wanting for HFSW was reduced at W11 but this was significant only for controls (p < 0.001, both the fasted and fed state) and postprandially in SG (p = 0.001).

Explicit wanting

Controls had greater explicit wanting for HFSW in the fasting state compared with RYGB at BL (p = 0.001). At W11, SG showed reduced explicit wanting for HFSA and HFSW in the fasted state (p = 0.008 and p = 0.001, respectively). At BL, controls had higher postprandial explicit wanting for HFSW (p = 0.002) and for LFSA and LFSW at W11 compared with RYGB (p = 0.001 and p = 0.004, respectively). At W11, SG showed a postprandial reduction in explicit wanting for HFSA (p = 0.001), HFSW (p = 0.001), and LFSW (p = 0.007) and RYGB for HFSA (p = 0.001), LFSA (p < 0.001), HFSW (p = 0.01), and LFSW (p < 0.001), whereas the control group showed reductions only for HFSW (p = 0.002).

DISCUSSION

The aim of this study was to compare how a similar weight loss achieved by a VLED alone or VLED in combination with the two most common bariatric procedures (SG and RYGB) impacted hedonic hunger and food reward in individuals with severe obesity. Baseline characteristics and changes in body weight and composition were matched among groups and paralleled by similar reductions in hedonic hunger. However, weight loss induced by SG and RYGB yielded several additional and favorable changes in food reward.

Few studies have investigated the impact of diet‐induced weight loss on hedonic hunger in individuals with obesity. Cameron and colleagues [31] reported that a 5% weight loss induced by a low‐energy diet did not change the reinforcing value of palatable snacks, but food “liking” increased by 10%, independently of the magnitude of weight loss. However, this was a small study (n = 15), and liking was measured as a global evaluation of a meal. A much larger study (n = 111) by O'Neil et al. [32] found that a 4% weight loss induced by a 12‐week commercial weight loss program, consisting of caloric restriction, encouragement of physical activity, and regular meetings, led to decreases in hedonic hunger. Similarly, a study by Ross et al. [33] reported that a 3‐month behavioral weight loss program resulted in reduced food reward sensitivity and impulsivity after an average 6‐kg (7%) weight loss. The two latter studies measured hedonic hunger with the PFS, and as such, results are similar and comparable with ours.

Ross et al. [33] reported that a greater food reward sensitivity (from PFS) was associated with greater body weight but not with weight loss. Contrarily, O'Neil and colleagues [32] showed that a decrease in the aggregated PFS score was associated with a greater percentage of weight loss and with improvements in reported weight control behaviors determined by the Eating Behavior Inventory.

To our knowledge, no studies have addressed the impact of SG on hedonic hunger. But several studies [11, 18, 34, 35], including the present one, suggest that bariatric surgery in general leads to reductions in hedonic hunger. Moreover, significantly reduced hedonic hunger post RYGB was shown to be parallel with more favorable changes in dietary habits, such as increased intake of protein‐rich foods and vegetables, as well as reduced consumption of sugary foods, snacks, and beverages [35]. Patients with severe obesity were shown to have higher hedonic hunger (aggregated score) compared with controls without obesity [11]. Furthermore, this difference was not seen between controls and patients who had already undergone RYGB ≥1 year ago [11]. Similarly, another study showed that hedonic hunger (“food available” and “food present”) was not different in patients who had undergone gastric banding 7 years ago (with BMI between 25 and 52 kg/m2) compared with individuals with a normal weight, and their scores were lower compared with individuals with severe obesity [18]. These two last studies suggest a “normalization” of hedonic hunger post bariatric surgery.

An overall improvement in food reward after weight loss was seen in the present analysis, but the results are not completely in line with previous findings. A 5% weight loss, induced by continuous or intermittent energy restriction, was reported to improve dietary restraint, craving control, and susceptibility to hunger and binge eating in women with overweight or obesity, despite no changes in liking and wanting for high‐fat foods relative to low‐fat foods, as measured by the LFPQ [36]. However, a recent study from the same group comparing absolute changes for each food category showed that weight loss decreased liking across all foods [37]. In the present study, only the surgical groups experienced reductions in both liking and wanting for all food categories, whereas the control group showed an increase in wanting for LFSA and a decrease in wanting for HFSW. Even though the changes in controls were overall favorable, food reward was still greater in several food categories post weight loss compared with the surgical groups, especially RYGB. Several aspects may account for the inconsistencies seen among the previously discussed studies. In the present study, weight loss (%) was larger and energy intake significantly lower (almost half) compared with the Oustric et al. study [36].

Martin and colleagues showed in a long‐term follow‐up study that a low‐carbohydrate diet decreased preferences for high‐carbohydrate/sugary foods, whereas a low‐fat diet decreased cravings for high‐fat foods, despite no differences in weight loss at 24 months between diets [38]. In this study, participants from both groups received a comprehensive treatment program to foster daily adherence [38]. This is in contrast to the study by Oustric et al. [37], in which no contact was made until the 1‐year follow‐up, wherein participants regained half of the weight initially lost, and food reward was no longer different from baseline. Martin et al. (2011) also reported that greater weight loss was associated with larger reductions in cravings for sweets and high‐fat foods, at 3 and 24 months, respectively, but in line with the present analysis, changes in food preferences did not correlate with weight loss [38].

Both SG [20, 21] and RYGB [21] patients have shown positive alterations in food reward and appetite behaviors post bariatric surgery. Comparing the two procedures, one study [21] showed that SG led to more favorable changes, with decreased preference for high‐sugar foods, whereas RYGB did not. Contrarily, we found RYGB to induce additional changes in liking and wanting for the different food categories but with no overall differences between the two. In line with this, a similar weight loss induced by either SG or RYGB was shown to lead to comparable changes on key factors involved in the regulation of eating behavior and hedonic components, such as frequency of food cravings, influence of emotions and external food cues, and favorable shifts in the pleasantness of sweets [25]. Dumping syndrome is a common side effect after bariatric surgery, especially post RYGB, and it was suggested to alter the pleasantness of foods, especially carbohydrate‐ and fat‐rich foods [39]. This might explain some of the differences seen between bariatric surgery and diet‐induced weight loss in the present and previously discussed studies. Moreover, individuals with obesity were reported to have decreased dopamine receptor availability [40], but bariatric surgery seemed to reverse this [41]. This could also serve as a possible mechanism for the additional improvements in food reward seen after bariatric surgery, compared with the control group.

Together with the current literature, the present findings have clinical implications for weight management. Overall, bariatric surgery seems to induce favorable (and sustained) changes in hedonic hunger, food reward, and weight control behavior toward a “normalization.” To some extent, this appears to be possible to manipulate, which is especially important for those receiving conservative treatment, as comprehensive behavioral interventions seem to play a key role in ameliorating hedonic hunger and food reward after weight loss with dietary restriction. Moreover, adding pharmacotherapy, namely the recently approved GLP‐1 receptor agonist [42], to lifestyle interventions might provide benefits on appetite behaviors and body weight, without the risks associated with bariatric surgery.

This study has several strengths. First, weight loss and diet were matched across groups, as well as sex distribution, age, and anthropometric variables, allowing for identification of the impact of SG and RYGB alone. Second, the significance level was adjusted for multicomparisons (Bonferroni) and for the large number of variables tested. This study also has some limitations. First, as the intervention period was 10 weeks, we could not ensure that measurements were taken in the same phase of the menstrual cycle, which is known to have an impact on appetite [43]. However, the distribution was likely to occur at random, so there is no strong indication that this constitutes an issue. Secondly, this was a secondary analysis of a trial powered to detect differences in postprandial GLP‐1 secretion between groups, and therefore, this study might be underpowered to look at hedonic appetite and food reward. Additionally, the small number of participants in each group might have increased the possibility of type II error and prevented the detection of true differences among groups. Third, even though validated questionnaires were used to measure hedonic eating and food reward, only one instrument was used to measure each construct, and other instruments measuring different constructs, which might be differently impacted by bariatric surgery, might provide different results. Fourth, the strict significance level imposed might have affected the results and prevented the identification of significant findings. Fifth, even though the standardization of the diet across groups is a strength, we cannot rule out that some of the differences found among groups, especially bariatric groups versus controls, is due to transitory changes in postoperative physiology, including fluid shifts and changes in absorption and metabolism. Finally, stress is a potential mediator for appetite and food cravings [44], and given that this study was carried out under unusual circumstances (COVID‐19 pandemic), stress could have affected our outcome variables.

CONCLUSION

Initial weight loss seems to reduce hedonic hunger, independent of modality. However, SG and RYGB led to several additional favorable changes in food reward. These preliminary findings need to be confirmed, and future research should also investigate the long‐term impact of both diet‐induced weight loss and bariatric surgery on hedonic hunger and food reward and how initial changes in these constructs might modulate long‐term weight loss outcomes.

AUTHOR CONTRIBUTIONS

CM and MIA formulated the research questions and designed the study. MIA, IØB, and SS carried out the study. GF analyzed data from the LFPQ. MIA analyzed the data. All authors were involved in the writing of the manuscript.

CONFLICT OF INTEREST

The authors declared no conflict of interest.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04051190.

ACKNOWLEDGMENTS

The authors thank all the participants for their time and commitment, Hege Bjøru and Sissel Salater (Centre of Obesity and Innovation [ObeCe], Clinic of Surgery, St. Olav University Hospital) for support with screening, Turid Follestad (NTNU) for guidance on statistical analysis, and the Clinic of Surgery at St. Olav University Hospital, Trondheim, and Namsos Hospital, both in Norway. The authors also thank Lighter Life, Harlow, Essex, UK, for providing food packs (no commercial interest).

Aukan MI, Brandsæter IØ, Skårvold S, et al. Changes in hedonic hunger and food reward after a similar weight loss induced by a very low‐energy diet or bariatric surgery. Obesity (Silver Spring). 2022;30(10):1963‐1972. doi: 10.1002/oby.23535

Funding information Liaison Committee between the Central Norway Regional Health Authority (RHA) and the Norwegian University of Science and Technology (NTNU)

REFERENCES

  • 1. Wing RR, Phelan S. Long‐term weight loss maintenance. Am J Clin Nutr. 2005;82(suppl 1):222S‐225S. [DOI] [PubMed] [Google Scholar]
  • 2. Sundström J, Bruze G, Ottosson J, Marcus C, Näslund I, Neovius M. Weight loss and heart failure: a nationwide study of gastric bypass surgery versus intensive lifestyle treatment. Circulation. 2017;135:1577‐1585. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 3. Al‐Najim W, Docherty NG, le Roux CW. Food intake and eating behavior after bariatric surgery. Physiol Rev. 2018;98:1113‐1141. [DOI] [PubMed] [Google Scholar]
  • 4. Murphy KG, Dhillo WS, Bloom SR. Gut peptides in the regulation of food intake and energy homeostasis. Endocr Rev. 2006;27:719‐727. [DOI] [PubMed] [Google Scholar]
  • 5. Berthoud HR, Münzberg H, Morrison CD. Blaming the brain for obesity: integration of hedonic and homeostatic mechanisms. Gastroenterology. 2017;152:1728‐1738. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6. Berthoud HR. Homeostatic and non‐homeostatic pathways involved in the control of food intake and energy balance. Obesity (Silver Spring). 2006;14(suppl 5):197S‐200S. [DOI] [PubMed] [Google Scholar]
  • 7. Berridge KC. ‘Liking’ and ‘wanting’ food rewards: brain substrates and roles in eating disorders. Physiol Behav. 2009;97:537‐550. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 8. Volkow ND, Wang GJ, Fowler JS, et al. "Nonhedonic" food motivation in humans involves dopamine in the dorsal striatum and methylphenidate amplifies this effect. Synapse. 2002;44:175‐180. [DOI] [PubMed] [Google Scholar]
  • 9. Lutter M, Nestler EJ. Homeostatic and hedonic signals interact in the regulation of food intake. J Nutr. 2009;139:629‐632. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10. Giesen JCAH, Havermans RC, Douven A, Tekelenburg M, Jansen A. Will work for snack food: the association of BMI and snack reinforcement. Obesity (Silver Spring). 2010;18:966‐970. [DOI] [PubMed] [Google Scholar]
  • 11. Schultes B, Ernst B, Wilms B, Thurnheer M, Hallschmid M. Hedonic hunger is increased in severely obese patients and is reduced after gastric bypass surgery. Am J Clin Nutr. 2010;92:277‐283. [DOI] [PubMed] [Google Scholar]
  • 12. Bartoshuk LM, Duffy VB, Hayes JE, Moskowitz HR, Snyder DJ. Psychophysics of sweet and fat perception in obesity: problems, solutions and new perspectives. Philos Trans R Soc Lond B Biol Sci. 2006;361:1137‐1148. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 13. Carvalho‐Ferreira JP, Finlayson G, da Cunha DT, Caldas G, Bandoni D, de Rosso VV. Adiposity and binge eating are related to liking and wanting for food in Brazil: a cultural adaptation of the Leeds food preference questionnaire. Appetite. 2019;133:174‐183. [DOI] [PubMed] [Google Scholar]
  • 14. Epstein LH, Carr KA, Lin H, Fletcher KD, Roemmich JN. Usual energy intake mediates the relationship between food reinforcement and BMI. Obesity (Silver Spring). 2012;20:1815‐1819. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15. Nymo S, Coutinho SR, Jørgensen J, et al. Timeline of changes in appetite during weight loss with a ketogenic diet. Int J Obes (Lond). 2017;41:1224‐1231. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16. Sumithran P, Prendergast LA, Delbridge E, et al. Long‐term persistence of hormonal adaptations to weight loss. N Engl J Med 2011;365:1597‐1604. [DOI] [PubMed] [Google Scholar]
  • 17. Oustric P, Gibbons C, Beaulieu K, Blundell J, Finlayson G. Changes in food reward during weight management interventions ‐ a systematic review. Obes Rev. 2018;19:1642‐1658. [DOI] [PubMed] [Google Scholar]
  • 18. Ullrich J, Ernst B, Wilms B, Thurnheer M, Hallschmid M, Schultes B. The hedonic drive to consume palatable foods appears to be lower in gastric band carriers than in severely obese patients who have not undergone a bariatric surgery. Obes Surg. 2013;23:474‐479. [DOI] [PubMed] [Google Scholar]
  • 19. Deloose E, Janssen P, Lannoo M, Van der Schueren B, Depoortere I, Tack J. Higher plasma motilin levels in obese patients decrease after Roux‐en‐Y gastric bypass surgery and regulate hunger. Gut. 2016;65:1110‐1118. [DOI] [PubMed] [Google Scholar]
  • 20. Ammon BS, Bellanger DE, Geiselman PJ, Primeaux SD, Yu Y, Greenway FL. Short‐term pilot study of the effect of sleeve gastrectomy on food preference. Obes Surg. 2015;25:1094‐1097. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21. Primeaux SD, Tzeng TH, Allerton TD, et al. Differences in short‐term food preferences following vertical sleeve gastrectomy and Roux‐en‐Y gastric bypass surgery. Obes Res Clin Pract. 2015;9:628‐632. [DOI] [PubMed] [Google Scholar]
  • 22. Leahey TM, Bond DS, Raynor H, et al. Effects of bariatric surgery on food cravings: do food cravings and the consumption of craved foods "normalize" after surgery? Surg Obes Relat Dis. 2012;8:84‐91. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 23. Olbers T, Björkman S, Lindroos A, et al. Body composition, dietary intake, and energy expenditure after laparoscopic Roux‐en‐Y gastric bypass and laparoscopic vertical banded gastroplasty: a randomized clinical trial. Ann Surg. 2006;244:715‐722. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 24. Bueter M, Miras AD, Chichger H, et al. Alterations of sucrose preference after Roux‐en‐Y gastric bypass. Physiol Behav. 2011;104:709‐721. [DOI] [PubMed] [Google Scholar]
  • 25. Nance K, Eagon JC, Klein S, Pepino MY. Effects of sleeve gastrectomy vs. Roux‐en‐Y gastric bypass on eating behavior and sweet taste perception in subjects with obesity. Nutrients. 2017;10:18. doi: 10.3390/nu10010018 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 26. Holinski F, Menenakos C, Haber G, Olze H, Ordemann J. Olfactory and gustatory function after bariatric surgery. Obes Surg. 2015;25:2314‐2320. [DOI] [PubMed] [Google Scholar]
  • 27. Jakicic JM, Marcus M, Gallagher KI, et al. Evaluation of the SenseWear Pro Armband to assess energy expenditure during exercise. Med Sci Sports Exerc. 2004;36:897‐904. [DOI] [PubMed] [Google Scholar]
  • 28. Lowe MR, Butryn ML, Didie ER, et al. The Power of Food Scale. A new measure of the psychological influence of the food environment. Appetite. 2009;53:114‐118. [DOI] [PubMed] [Google Scholar]
  • 29. Oustric P, Thivel D, Dalton M, et al. Measuring food preference and reward: application and cross‐cultural adaptation of the Leeds Food Preference Questionnaire in human experimental research. Food Qual Prefer. 2020;80:103824. doi: 10.1016/j.foodqual.2019.103824 [DOI] [Google Scholar]
  • 30. Iepsen EW, Lundgren J, Holst JJ, Madsbad S, Torekov SS. Successful weight loss maintenance includes long‐term increased meal responses of GLP‐1 and PYY3‐36. Eur J Endocrinol. 2016;174:775‐784. [DOI] [PubMed] [Google Scholar]
  • 31. Cameron JD, Goldfield GS, Cyr MJ, Doucet E. The effects of prolonged caloric restriction leading to weight‐loss on food hedonics and reinforcement. Physiol Behav. 2008;94:474‐480. [DOI] [PubMed] [Google Scholar]
  • 32. O'Neil PM, Theim KR, Boeka A, Johnson G, Miller‐Kovach K. Changes in weight control behaviors and hedonic hunger during a 12‐week commercial weight loss program. Eat Behav. 2012;13:354‐360. [DOI] [PubMed] [Google Scholar]
  • 33. Ross KM, Eastman A, Ugwoaba UA, Demos KE, Lillis J, Wing RR. Food reward sensitivity, impulsivity, and weight change during and after a 3‐month weight loss program. PLoS One. 2020;15:e0243530. doi: 10.1371/journal.pone.0243530 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 34. Cushing CC, Benoit SC, Peugh JL, Reiter‐Purtill J, Inge TH, Zeller MH. Longitudinal trends in hedonic hunger after Roux‐en‐Y gastric bypass in adolescents. Surg Obes Relat Dis. 2014;10:125‐130. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 35. Ullrich J, Ernst B, Wilms B, Thurnheer M, Schultes B. Roux‐en Y gastric bypass surgery reduces hedonic hunger and improves dietary habits in severely obese subjects. Obes Surg. 2013;23:50‐55. [DOI] [PubMed] [Google Scholar]
  • 36. Beaulieu K, Casanova N, Oustric P, et al. Matched weight loss through intermittent or continuous energy restriction does not lead to compensatory increases in appetite and eating behavior in a randomized controlled trial in women with overweight and obesity. J Nutr. 2020;150:623‐633. [DOI] [PubMed] [Google Scholar]
  • 37. Oustric P, Beaulieu K, Casanova N, et al. Food liking but not wanting decreases after controlled intermittent or continuous energy restriction to ≥5% weight loss in women with overweight/obesity. Nutrients. 2021;13:182. doi: 10.3390/nu13010182 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 38. Martin CK, Rosenbaum D, Han H, et al. Change in food cravings, food preferences, and appetite during a low‐carbohydrate and low‐fat diet. Obesity (Silver Spring). 2011;19:1963‐1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 39. Laurenius A, Werling M, le Roux CW, Fandriks L, Olbers T. Dumping symptoms is triggered by fat as well as carbohydrates in patients operated with Roux‐en‐Y gastric bypass. Surg Obes Relat Dis. 2017;13:1159‐1164. [DOI] [PubMed] [Google Scholar]
  • 40. Wang GJ, Volkow ND, Logan J , et al. Brain dopamine and obesity. Lancet. 2001;357(9253):354‐357. [DOI] [PubMed] [Google Scholar]
  • 41. Karlsson HK, Tuominen L, Helin S, Salminen P, Nuutila P, Nummenmaa L . Mesolimbic opioid‐dopamine interaction is disrupted in obesity but recovered by weight loss following bariatric surgery. Transl Psychiatry. 2021;11(1):259. doi: 10.1038/s41398-021-01370-2 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 42. Gibbons C, Blundell J, Tetens Hoff S, Dahl K, Bauer R, Baekdal T. Effects of oral semaglutide on energy intake, food preference, appetite, control of eating and body weight in subjects with type 2 diabetes. Diabetes Obes Metab. 2021;23:581‐588. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 43. Dye L, Blundell JE. Menstrual cycle and appetite control: implications for weight regulation. Hum Reprod. 1997;12:1142‐1151. [DOI] [PubMed] [Google Scholar]
  • 44. Chao A, Grilo CM, White MA, Sinha R. Food cravings mediate the relationship between chronic stress and body mass index. J Health Psychol. 2015;20:721‐729. [DOI] [PMC free article] [PubMed] [Google Scholar]

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