Adherence to Hunger Training over 6 Months and the Effect on Weight and Eating Behaviour: Secondary Analysis of a Randomised Controlled Trial

A low-glucose eating pattern is associated with improvements in glycemic variability among women at risk for postmenopausal breast cancer: an exploratory analysis

Background

High glycemic variability (GV) is a biomarker of cancer risk, even in the absence of diabetes. The emerging concept of chrononutrition suggests that modifying meal timing can favorably impact metabolic risk factors linked to diet-related chronic disease, including breast cancer. Here, we examined the potential of eating when glucose levels are near personalized fasting thresholds (low-glucose eating, LGE), a novel form of timed-eating, to reduce GV in women without diabetes, who are at risk for postmenopausal breast cancer.

Methods

In this exploratory analysis of our 16-week weight loss randomized controlled trial, we included 17 non-Hispanic, white, postmenopausal women (average age = 60.7 ± 5.8 years, BMI = 34.5 ± 6.1 kg/m2, HbA1c = 5.7 ± 0.3%). Participants were those who, as part of the parent study, provided 3-7 days of blinded, continuous glucose monitoring data and image-assisted, timestamped food records at weeks 0 and 16. Pearson's correlation and multivariate regression were used to assess associations between LGE and GV, controlling for concurrent weight changes.

Results

Increases in LGE were associated with multiple unfavorable measures of GV including reductions in CGM glucose mean, CONGA, LI, J-Index, HBGI, ADDR, and time spent in a severe GV pattern (r = -0.81 to -0.49; ps < 0.044) and with increases in favorable measures of GV including M-value and LBGI (r = 0.59, 0.62; ps < 0.013). These associations remained significant after adjusting for weight changes.

Conclusion

Low-glucose eating is associated with improvements in glycemic variability, independent of concurrent weight reductions, suggesting it may be beneficial for GV-related disease prevention. Further research in a larger, more diverse sample with poor metabolic health is warranted.Clinical trial registration: ClinicalTrials.gov, NCT03546972.

Exploring the Impact of Dawn Phenomenon on Glucose-Guided Eating Thresholds in Individuals With Type 2 Diabetes Using Continuous Glucose Monitoring: Observational Study

BACKGROUND

Glucose-guided eating (GGE) improves metabolic markers of chronic disease risk, including insulin resistance, in adults without diabetes. GGE is a timed eating paradigm that relies on experiencing feelings of hunger and having a preprandial glucose level below a personalized threshold computed from 2 consecutive morning fasting glucose levels. The dawn phenomenon (DP), which results in elevated morning preprandial glucose levels, could cause typically derived GGE thresholds to be unacceptable or ineffective among people with type 2 diabetes (T2DM).

OBJECTIVE

The aim of this study is to quantify the incidence and day-to-day variability in the magnitude of DP and examine its effect on morning preprandial glucose levels as a preliminary test of the feasibility of GGE in adults with T2DM.

METHODS

Study participants wore a single-blinded Dexcom G6 Pro continuous glucose monitoring (CGM) system for up to 10 days. First and last eating times and any overnight eating were reported using daily surveys over the study duration. DP was expressed as a dichotomous variable at the day level (DP day vs non-DP day) and as a continuous variable reflecting the percent of days DP was experienced on a valid day. A valid day was defined as having no reported overnight eating (between midnight and 6 AM). ∂ Glucose was computed as the difference in nocturnal glucose nadir (between midnight and 6 AM) to morning preprandial glucose levels. ∂ Glucose ≥20 mg/dL constituted a DP day. Using multilevel modeling, we examined the between- and within-person effects of DP on morning preprandial glucose and the effect of evening eating times on DP.

RESULTS

In total, 21 adults (59% female; 13/21, 62%) with non-insulin-treated T2DM wore a CGM for an average of 10.5 (SD 1.1) days. Twenty out of 21 participants (95%) experienced DP for at least 1 day, with an average of 51% of days (SD 27.2; range 0%-100%). The mean ∂ glucose was 23.7 (SD 13.2) mg/dL. People who experience DP more frequently had a morning preprandial glucose level that was 54.1 (95% CI 17.0-83.9; P<.001) mg/dL higher than those who experienced DP less frequently. For within-person effect, morning preprandial glucose levels were 12.1 (95% CI 6.3-17.8; P=.008) mg/dL higher on a DP day than on a non-DP day. The association between ∂ glucose and preprandial glucose levels was 0.50 (95% CI 0.37-0.60; P<.001). There was no effect of the last eating time on DP.

CONCLUSIONS

DP was experienced by most study participants regardless of last eating times. The magnitude of the within-person effect of DP on morning preprandial glucose levels was meaningful in the context of GGE. Alternative approaches for determining acceptable and effective GGE thresholds for people with T2DM should be explored and evaluated.

Eating behaviour traits mediate the association between satiety responsiveness and energy intake among individuals with overweight and obesity

Whether eating behaviour traits represent factors that could explain the susceptibility to overeating in individuals with low satiety responsiveness remain to be extensively examined. This study aimed to assess if eating behaviours mediate the association between satiety responsiveness and energy intake. Baseline data from individuals with overweight or obesity (n = 303; age = 38.7 ± 8.4 years; BMI = 33.2 ± 3.4 kg/m², 56% women) who participated in four weight-loss studies were included in this cross-sectional study. Satiety responsiveness was determined by the satiety quotient (SQ) based on fullness sensations in response to a standardized breakfast. Energy intake was self-reported in a three-day food record and measured by an ad libitum buffet meal. Eating behaviours were assessed with questionnaires. Mediation analyses adjusted for age and sex, and for underreporting for the food record, were performed using a regression-based and bootstrapping approach. The association between SQ and self-reported total energy intake was mediated by susceptibility to hunger (β = -2.51 ± 1.26, 95% CI, -5.38 to -0.52) and its subscales, internal and external locus of hunger (β = -2.00 ± 1.10, 95% CI, -4.50 to -0.28 and β = -2.42 ± 1.29, 95% CI, -5.30 to -0.30, respectively). Susceptibility to hunger (β = -2.71 ± 1.13, 95% CI, -5.29 to -0.84), internal and external locus of hunger (β = -1.84 ± 0.95, 95% CI -4.00 to -0.30 and β = -3.42 ± 1.31, 95% CI, -6.39 to -1.24, respectively), cues that may trigger food cravings (β = -5.43 ± 2.91, 95% CI, -11.83 to -0.44) and state-craving as a physiological state (β = -4.31 ± 2.51, 95%CI, -10.14 to -0.44) also mediated the association between SQ and measured energy intake. These results suggest that susceptibility to hunger and food cravings partly explained the susceptibility to overeating among individuals with low satiety responsiveness. Interventions targeting susceptibility to hunger and food cravings may thus be helpful to prevent overeating among these individuals.

A Low-Glucose Eating Pattern Improves Biomarkers of Postmenopausal Breast Cancer Risk: An Exploratory Secondary Analysis of a Randomized Feasibility Trial

Postmenopausal breast cancer is the most common obesity-related cancer death among women in the U.S. Insulin resistance, which worsens in the setting of obesity, is associated with higher breast cancer incidence and mortality. Maladaptive eating patterns driving insulin resistance represent a key modifiable risk factor for breast cancer. Emerging evidence suggests that time-restricted feeding paradigms (TRF) improve cancer-related metabolic risk factors; however, more flexible approaches could be more feasible and effective. In this exploratory, secondary analysis, we identified participants following a low-glucose eating pattern (LGEP), defined as consuming energy when glucose levels are at or below average fasting levels, as an alternative to TRF. Results show that following an LGEP regimen for at least 40% of reported eating events improves insulin resistance (HOMA-IR) and other cancer-related serum biomarkers. The magnitude of serum biomarkers changes observed here has previously been shown to favorably modulate benign breast tissue in women with overweight and obesity who are at risk for postmenopausal breast cancer. By comparison, the observed effects of LGEP were similar to results from previously published TRF studies in similar populations. These preliminary findings support further testing of LGEP as an alternative to TRF and a postmenopausal breast cancer prevention strategy. However, results should be interpreted with caution, given the exploratory nature of analyses.

Hunger Training as a self-regulation strategy in a comprehensive weight loss program for breast cancer prevention: a randomized feasibility study

Weight losses >10% favorably modulate biomarkers of breast cancer risk but are not typically achieved by comprehensive weight loss programs, including the Diabetes Prevention Program (DPP). Combining the DPP with Hunger Training (HT), an evidence-based self-regulation strategy that uses self-monitored glucose levels to guide meal timing, has potential to enhance weight losses and cancer-related biomarkers, if proven feasible. This 2-arm RCT examined the feasibility of adding HT to the DPP and explored effects on weight and metabolic and breast cancer risk biomarkers. Fifty postmenopausal women (BMI > 27 kg/m2) at risk of breast cancer were randomized to the DPP+HT or DPP-only arm. Both arms followed a 16-week version of the DPP delivered weekly by a trained registered dietitian. Those in the DPP+HT also wore a continuous glucose monitor during weeks 4-6 of the program. Feasibility criteria were accrual rates > 50%, retention rates > 80%, and adherence to the HT protocol >75%. All a priori feasibility criteria were achieved. The accrual rate was 67%; retention rate was 81%; and adherence to HT was 90%. Weight losses and BMI reductions were significant over time as were changes in metabolic and breast cancer risk biomarkers but did not vary by group. This trial demonstrated that HT was feasible to add to comprehensive weight management program targeted towards postmenopausal women at high risk of breast cancer, though upon preliminary examination it does not appear to enhance weight loss or metabolic changes.

Teaching people to eat according to appetite - Does the method of glucose measurement matter?

BACKGROUND

Hunger training teaches people to eat according to their appetite using pre-prandial glucose measurement. Previous hunger training interventions used fingerprick blood glucose, however continuous glucose monitoring (CGM) offers a painless and convenient form of glucose monitoring. The aim of this randomised feasibility trial was to compare hunger training using CGM with fingerprick glucose monitoring in terms of adherence to the protocol, acceptability, weight, body composition, HbA1c, psychosocial variables, and the relationship between adherence measures and weight loss.

METHODS

40 adults with obesity were randomised to either fingerpricking or scanning with a CGM and followed identical interventions for 6 months, which included 1 month of only eating when glucose was under their individualised glucose cut-off. For months 2-6 participants relied on their sensations of hunger to guide their eating and filled in a booklet.

RESULTS

90% of the fingerpricking group and 85% of the scanning group completed the study. Those using the scanner measured their glucose an extra 1.9 times per day (95% CI 0.9, 2.8, p < 0.001) compared with those testing by fingerprick. Both groups lost similar amounts of weight over 6 months (on average 4 kg), were satisfied with the hunger training program and wanted to measure their glucose again within the next year. There were no differences between groups in terms of intervention acceptability, weight, body composition, HbA1c, eating behaviours, or psychological health. Frequency of glucose testing and booklet entry both predicted a clinically meaningful amount of weight loss.

CONCLUSIONS

Either method of measuring glucose is effective for learning to eat according to hunger using the hunger training program. As scanning with a CGM encouraged better adherence to the protocol without sacrificing outcome results, future interventions should consider using this new technology in hunger training programs.

Translating hunger training research to primary health: a qualitative study of nurse attitudes towards a novel weight management intervention

INTRODUCTION Practice nurses in general practice are ideally placed to deliver weight management treatments. Teaching people to eat according to their appetite, based on measurements of blood glucose ('hunger training'), is known to lead to weight loss and improved eating behaviour. To effectively translate this research to primary care requires understanding of key stakeholder perspectives. AIM The aim of this study was to explore the perspectives of practice nurses on the suitability of using hunger training as a weight management intervention in general practice. METHODS Ten nurses trialled hunger training for 1 week, followed by a semi-structured interview where they were asked about their experience; perceived patient interest; enablers and barriers; and suggested changes to hunger training. RESULTS All nurses were positive about hunger training and wanted to use it with their patients. They thought it was a useful method for teaching patients about eating according to their appetite, and the impact of food choices on glucose. Motivation was seen to be both an important potential barrier and enabler for patients. Other anticipated patient enablers included the educational value of hunger training and ease of the programme. Other barriers included lack of time and cost of equipment and appointments. For most nurses, 1 week of following hunger training was sufficient training to deliver the intervention. Suggested refinements included adding nutrition advice to the booklet, incorporating other health goals and enabling social support. DISCUSSION These findings suggest that hunger training could be translated to primary care with minor modifications.

'Am I really hungry?' A qualitative exploration of patients' experience, adherence and behaviour change during hunger training: a pilot study

OBJECTIVES

Hunger training (HT) is an intervention designed to teach people to eat according to their hunger by connecting physical symptoms of appetite with glucose levels. HT is most effective for weight loss, and improving eating behaviours when adherence is high. However, adherence is a challenge that should be explored prior to wider dissemination. The aim of this study was to explore participants' experience and self-reported adherence and behaviour change related to HT.

DESIGN

A qualitative study, nested within a randomised controlled pilot study of two different methods of monitoring glucose during HT. Semistructured interviews were audio-recorded, transcribed verbatim and analysed thematically using a phenomenological approach.

SETTING

Single-centre study with participants recruited from the local area.

PARTICIPANTS

40 participants began the pilot study and 38 participants (52.6% women) remained at 1 month and completed interviews.

RESULTS

Most participants felt they were able to match their hunger to their glucose levels by the end of the intervention. The main adherence barriers were the social pressure to eat, lack of time and lack of flexibility in participants' meal schedules. Common adherence enablers were having a set routine, social support and accountability. Participants described increased awareness of hungry versus non-hungry eating and better cognition of feelings of hunger and satiety as a result of the intervention, which in turn led to changes of food choice, portion size and adjusted meal timing and frequency.

CONCLUSIONS

Findings show that HT is acceptable from a patient perspective, and results can be used to inform the translation of HT programme to healthcare settings.

TRIAL REGISTRATION NUMBER

ACTRN12618001257257.

Effect of Energy Restriction on Eating Behavior Traits and Psychobehavioral Factors in the Low Satiety Phenotype

Studies have shown that individuals with low satiety efficiency may be more susceptible to weight gain, but little is known about the effect of weight loss intervention outcomes in these individuals. This study aimed to evaluate the impact of an energy-restricted weight loss intervention on eating behavior traits and psychobehavioral factors in individuals differing in their satiety responsiveness. A pooled cohort of individuals who were overweight or obese (n = 100; aged 39 ± 9 years) participating in a 12- to 15-week weight loss program targeting an energy deficit of 500–700 kcal/day were included in this study. Satiety responsiveness was determined by a median split of the mean satiety quotient based on appetite sensations measured in response to a test meal at baseline (low satiety responsiveness (LSR) vs. high satiety responsiveness (HSR)). Anthropometric variables, eating behavior traits, psychobehavioral factors, and ad libitum energy intake were assessed before and after the intervention. Although similar weight loss was observed between the LSR and HSR groups (−3.5 ± 3.2 vs. −3.8 ± 2.8 kg, p = 0.64) in response to an energy-restricted weight loss intervention, changes in eating behavior traits were different between groups. Individuals with LSR had a higher increase in cognitive restraint (+5.5 ± 4.1 vs. +3.5 ± 3.5, p = 0.02) and some of its subscales and a lower decrease in situational susceptibility to disinhibition (−0.6 ± 1.1 vs. −1.2 ± 1.3, p = 0.02) in response to the intervention compared to the HSR group. In conclusion, energy-restricted weight loss intervention seems to trigger undesirable changes in some eating behavior traits in individuals more vulnerable to overeating, which could increase their susceptibility to weight regain.