This study aimed to investigate whether psychological distress, whole-grain consumption and tryptophan metabolism are associated with participants undergoing weight management intervention. Seventy-nine women and men (mean age 49·7 (sd 9·0) years; BMI 34·2(sd 2·5) kg/m2) participated in a 7-week weight-loss (WL) period and in a 24-week weight maintenance (WM) intervention period. Whole-grain consumption was measured using 4 d food diaries. Psychological distress was assessed with the General Health Questionnaire-12 (GHQ), and participants were divided into three GHQ groups based on the GHQ scores before WL. Tryptophan metabolites were determined from the participants’ fasting plasma using liquid chromatography-MS. GHQ scores were not associated with the whole-grain consumption. A positive association was observed between the whole-grain consumption and indole propionic acid (IPA) during the WM (P = 0·033). Serotonin levels were higher after the WL in the lowest GHQ tertile (P = 0·033), while the level at the end of the WM was higher compared with other timepoints in the highest GHQ tertile (P = 0·015 and P = 0·001). This difference between groups was not statistically significant. Furthermore, levels of several tryptophan metabolites changed within the groups during the study. Tryptophan metabolism changed during the study in the whole study group, independently from the level of psychological distress. The association between whole-grain consumption and IPA is possibly explained by the effects of dietary fibre on gut microbiota. This broadens the understanding of the pathways behind the health benefits associated with the intake of whole grains.

The purpose of this study was to assess impact of different volumes of exercise as well as cumulative moderate to vigorous physical activity (MVPA) on energy intake (EI) and diet quality, as assessed by the Healthy Eating Index-2010(HEI-2010), across a 12-month weight maintenance intervention. Participants were asked to attend group behavioural sessions, eat a diet designed for weight maintenance and exercise either 150, 225 or 300 min/week. Dietary intake was assessed by 3-d food records, and MVPA was assessed by accelerometry. Two hundred and twenty-four participants (42·5 years of age, 82 % female) provided valid dietary data for at least one time point. There was no evidence of group differences in EI, total HEI-2010 score or any of the HEI-2010 component scores (all P > 0·05). After adjusting for age, sex, time, group and group-by-time interactions, there was an effect of cumulative MVPA on EI (1·08, P = 0·04), total HEI-2010 scores (–0·02, P = 0·003), Na (–0·006, P = 0·002) and empty energy scores (–0·007, P = 0·004. There was evidence of a small relationship between cumulative daily EI and weight (β: 0·00187, 95 % CI 0·001, P = 0·003). However, there was no evidence for a relationship between HEI total score (β: −0·006, 95 % CI 0·07, 0·06) or component scores (all P > 0·05) and change in weight across time. The results of this study suggest that increased cumulative MVPA is associated with clinically insignificant increases in EI and decreases in HEI.

New dietary-based concepts are needed for treatment and effective prevention of overweight and obesity. The primary objective was to investigate if reduction in appetite is associated with improved weight loss maintenance. This cohort study was nested within the European Commission project Satiety Innovation (SATIN). Participants achieving ≥8% weight loss during an initial 8-week low-energy formula diet were included in a 12-week randomised double-blind parallel weight loss maintenance intervention. The intervention included food products designed to reduce appetite or matching controls along with instructions to follow national dietary guidelines. Appetite was assessed by ad libitum energy intake and self-reported appetite evaluations using visual analogue scales during standardised appetite probe days. These were evaluated at the first day of the maintenance period compared with baseline (acute effects after a single exposure of intervention products) and post-maintenance compared with baseline (sustained effects after repeated exposures of intervention products) regardless of randomisation. A total of 181 participants (forty-seven men and 134 women) completed the study. Sustained reduction in 24-h energy intake was associated with improved weight loss maintenance (R 0·37; P = 0·001), whereas the association was not found acutely (P = 0·91). Suppression in self-reported appetite was associated with improved weight loss maintenance both acutely (R −0·32; P = 0·033) and sustained (R −0·33; P = 0·042). Reduction in appetite seems to be associated with improved body weight management, making appetite-reducing food products an interesting strategy for dietary-based concepts.

Obesity is associated with elevated levels of inflammation and metabolic abnormalities which are linked to CVD. The aim of the present study was to investigate whether long-chain n-3 PUFA (LCn-3PUFA), combined with a very-low-energy diet (VLED), facilitated weight loss and weight maintenance, and improvements in blood lipids and inflammatory mediators. This was a double-blind, randomised, controlled trial with two parallel groups. For 14 weeks, one group consumed 6 × 1 g capsules/d of monounsaturated oil (placebo group, PB), and the other group consumed 6 × 1 g capsules/d of LCn-3PUFA (fish oil group, FO), each comprising 70 mg EPA and 270 mg DHA. Both groups were on VLED for 4 weeks (n 14 PB, n 18 FO), which was then followed by 10 weeks of weight maintenance (n 12 PB, n 17 FO). Fasting blood samples, anthropometric measurements and 3 d food diaries were collected at baseline, at 4 and 14 weeks. A greater-than-2-fold increase occurred in plasma levels of EPA and DHA in the FO group (P < 0·001). At 4 weeks, the mean weight loss was − 6·54 (sd 2·08) kg ( − 6·9 %) for PB and − 6·87 (sd 1·83) kg ( − 7·7 %) for FO. At week 14, after the maintenance phase, there was a further mean decrease in weight, − 1·57 (sd 3·7) kg (1·85 %) for PB and − 1·69 (sd 2·32) kg ( − 1·9 %) for FO. Both groups experienced improved metabolic profiles and there was a significant reduction in fat mass for the FO group at week 14 but not for PB. However, it would appear that supplementation with LCn-3PUFA had no significant effect on weight loss or weight maintenance over the 14 weeks.

Glucagon-like peptide 1 (GLP-1) is a peptide hormone that is released in response to nutrient ingestion. Postprandial GLP-1 release has been reported to be attenuated in obese subjects, but reports on the effect of weight loss on GLP-1 are conflicting. The aim of the present study was to clarify the effect of a weight-loss period and a consecutive weight-maintenance period on nutrient-stimulated GLP-1 release in obese subjects. Nutrient-stimulated (standard breakfast; 1·9MJ) GLP-1 release was investigated in thirty-two obese subjects on three occasions: before weight loss (T1) (BMI 30·0 (sd 2·5) kg/m2); after a 6-week very-low-energy diet (VLED) (T2) (BMI 27·6 (sd 2·3) kg/m2); after a 3-month weight-maintenance period (T3) (BMI 27·9 (sd 2·3) kg/m2). At each occasion, following a fasting blood sample the test meal was fed and blood was drawn every 30min for 2h relative to ingestion in order to determine plasma GLP-1, insulin, glucose and NEFA concentrations. Subjects lost 7 (sd 3·4) kg during the VLED (P<0·0001) and regained 1 (sd 3·2) kg during the weight-maintenance period (NS). The area under the curve for nutrient-stimulated plasma GLP-1 (pmol/l×h) was significantly decreased (P=0·01) at T2 (6·8 (sd 1)) compared with T1 (12·8 (sd 2·9)) and T3 (11·1 (sd 1·5)). Since we found a rebound of concentrations after a weight-maintenance period, decrease after weight loss seems to be transient and possibly due to a negative energy balance.

Since long-term weight maintenance (WM) is a major problem, interventions to improve WM are needed. The aim of the study was to investigate whether the addition of protein to the diet might limit weight regain after a weight loss of 5–10 % in overweight subjects. In a randomised parallel study design, 113 overweight subjects (BMI 29·3 (SD 2·5) kg/m2); age 45·1 (SD 10·4) years) followed a very-low-energy diet for 4 weeks, after which there was a 6-month period of WM. During WM, subjects were randomised into either a protein group or a control group. The protein group received 30 g/d protein in addition to their own usual diet. During the very-low-energy diet, no differences were observed between the groups. During WM, the protein group showed a higher protein intake (18 % v. 15 %; P<0·05), a lower weight regain (0·8 v. 3·0 kg; P<0·05), a decreased waist circumference (−1·2 (SD 0·7) v. 0·5 (SD 0·5 ) cm; P<0·05) and a smaller increase in respiratory quotient (0·03 (SD 0·01) v. 0·07 0·01; (SD/)P <0·05) compared with the control group. Weight regain in the protein group consisted of only fat-free mass, whereas the control group gained fat mass as well. Satiety in the fasted state before breakfast increased significantly more in the protein group than in the control group. After 6 months follow-up, body weight showed a significant group × time interaction. A protein intake of 18 % compared with 15 % resulted in improved WM in overweight subjects after a weight loss of 7·5 %. This improved WM implied several factors, i.e. improved body composition, fat distribution, substrate oxidation and satiety.