Reductions in food cravings are similar with low-fat weight loss diets differing in protein and carbohydrate in overweight and obese adults with type 2 diabetes: A randomized clinical trial

Management of a Dual Low Sodium and Diabetic Diet by Patient-Caregiver Dyads: A Qualitative Descriptive Study

PURPOSE

The purpose of the study was to explore factors surrounding management of simultaneous dietary recommendations for heart failure and type 2 diabetes among patient-caregiver dyads.

METHODS

Qualitative description was used to explore dyad experiences managing a dual diet. Semi-structured interviews were conducted with patients with a concurrent diagnosis of type 2 diabetes and heart failure and their family caregiver. Each 60-minute interview was conducted virtually. Interviews were audio recorded and transcribed verbatim. Thematic analysis was conducted with coding used for themes at dyadic-and individual levels.

RESULTS

Twelve patient-caregiver dyads (N = 24) were interviewed. The mean age was 57 years (±15 years). Most participants were white (75%); patients were predominantly male, and caregivers were predominantly female (83.3% for both). Dyadic-level themes that emerged included factors that influence simultaneous management of dual diet recommendations. Themes included shared barriers, facilitators, motivators, and strategies for dual diet management. Individual-level themes discussed by patients were barriers and motivators to dual diet management, and caregivers discussed barriers to supporting dual diet management.

CONCLUSIONS

Findings from the study highlight that patients and caregivers often work together and share similar barriers, facilitators, motivators, and strategies for adhering to a dual diet. The results provide insight into chronic disease management at the family level and can guide health care providers' efforts to promote family involvement with dietary recommendations for patients with multiple comorbidities.

Practical strategies to manage obesity in type 2 diabetes

The rising phenomenon of obesity, a major risk factor for the development and progression of type 2 diabetes, is a complex and multifaceted issue that requires a comprehensive and coordinated approach to be prevented and managed. Although novel pharmacological measures to combat obesity have achieved unprecedented efficacy, a healthy lifestyle remains essential for the long-term success of any therapeutic intervention. However, this requires a high level of intrinsic motivation and continued behavioural changes in the face of multiple metabolic, psychological and environmental factors promoting weight gain, particularly in the context of type 2 diabetes. This review is intended to provide practical recommendations in the context of a holistic, person-centred approach to weight management, including evidence-based and expert recommendations addressing supportive communication, shared decision-making, as well as nutritional and pharmacological therapeutic approaches to achieve sustained weight loss.

Food Cravings and Obesity in Women with Polycystic Ovary Syndrome: Pathophysiological and Therapeutic Considerations

Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, constitutes a metabolic disorder frequently associated with obesity and insulin resistance (IR). Furthermore, women with PCOS often suffer from excessive anxiety and depression, elicited by low self-esteem due to obesity, acne, and hirsutism. These mood disorders are commonly associated with food cravings and binge eating. Hypothalamic signaling regulates appetite and satiety, deteriorating excessive food consumption. However, the hypothalamic function is incapable of compensating for surplus food in women with PCOS, leading to the aggravation of obesity and a vicious circle. Hyperandrogenism, IR, the reduced secretion of cholecystokinin postprandially, and leptin resistance defined by leptin receptors' knockout in the hypothalamus have been implicated in the pathogenesis of hypothalamic dysfunction and appetite dysregulation. Diet modifications, exercise, and psychological and medical interventions have been applied to alleviate food disorders, interrupting the vicious circle. Cognitive-behavioral intervention seems to be the mainstay of treatment, while the role of medical agents, such as GLP-1 analogs and naltrexone/bupropion, has emerged.

Low-carbohydrate versus balanced-carbohydrate diets for reducing weight and cardiovascular risk

BACKGROUND

Debates on effective and safe diets for managing obesity in adults are ongoing. Low-carbohydrate weight-reducing diets (also known as 'low-carb diets') continue to be widely promoted, marketed and commercialised as being more effective for weight loss, and healthier, than 'balanced'-carbohydrate weight-reducing diets.

OBJECTIVES

To compare the effects of low-carbohydrate weight-reducing diets to weight-reducing diets with balanced ranges of carbohydrates, in relation to changes in weight and cardiovascular risk, in overweight and obese adults without and with type 2 diabetes mellitus (T2DM).

SEARCH METHODS

We searched MEDLINE (PubMed), Embase (Ovid), the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science Core Collection (Clarivate Analytics), ClinicalTrials.gov and WHO International Clinical Trials Registry Platform (ICTRP) up to 25 June 2021, and screened reference lists of included trials and relevant systematic reviews. Language or publication restrictions were not applied.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in adults (18 years+) who were overweight or living with obesity, without or with T2DM, and without or with cardiovascular conditions or risk factors. Trials had to compare low-carbohydrate weight-reducing diets to balanced-carbohydrate (45% to 65% of total energy (TE)) weight-reducing diets, have a weight-reducing phase of 2 weeks or longer and be explicitly implemented for the primary purpose of reducing weight, with or without advice to restrict energy intake.  DATA COLLECTION AND ANALYSIS: Two review authors independently screened titles and abstracts and full-text articles to determine eligibility; and independently extracted data, assessed risk of bias using RoB 2 and assessed the certainty of the evidence using GRADE. We stratified analyses by participants without and with T2DM, and by diets with weight-reducing phases only and those with weight-reducing phases followed by weight-maintenance phases. Primary outcomes were change in body weight (kg) and the number of participants per group with weight loss of at least 5%, assessed at short- (three months to < 12 months) and long-term (≥ 12 months) follow-up.

MAIN RESULTS

We included 61 parallel-arm RCTs that randomised 6925 participants to either low-carbohydrate or balanced-carbohydrate weight-reducing diets. All trials were conducted in high-income countries except for one in China. Most participants (n = 5118 randomised) did not have T2DM. Mean baseline weight across trials was 95 kg (range 66 to 132 kg). Participants with T2DM were older (mean 57 years, range 50 to 65) than those without T2DM (mean 45 years, range 22 to 62). Most trials included men and women (42/61; 3/19 men only; 16/19 women only), and people without baseline cardiovascular conditions, risk factors or events (36/61). Mean baseline diastolic blood pressure (DBP) and low-density lipoprotein (LDL) cholesterol across trials were within normal ranges. The longest weight-reducing phase of diets was two years in participants without and with T2DM. Evidence from studies with weight-reducing phases followed by weight-maintenance phases was limited. Most trials investigated low-carbohydrate diets (> 50 g to 150 g per day or < 45% of TE; n = 42), followed by very low (≤ 50 g per day or < 10% of TE; n = 14), and then incremental increases from very low to low (n = 5). The most common diets compared were low-carbohydrate, balanced-fat (20 to 35% of TE) and high-protein (> 20% of TE) treatment diets versus control diets balanced for the three macronutrients (24/61). In most trials (45/61) the energy prescription or approach used to restrict energy intake was similar in both groups. We assessed the overall risk of bias of outcomes across trials as predominantly high, mostly from bias due to missing outcome data. Using GRADE, we assessed the certainty of evidence as moderate to very low across outcomes.  Participants without and with T2DM lost weight when following weight-reducing phases of both diets at the short (range: 12.2 to 0.33 kg) and long term (range: 13.1 to 1.7 kg).  In overweight and obese participants without T2DM: low-carbohydrate weight-reducing diets compared to balanced-carbohydrate weight-reducing diets (weight-reducing phases only) probably result in little to no difference in change in body weight over three to 8.5 months (mean difference (MD) -1.07 kg, (95% confidence interval (CI) -1.55 to -0.59, I2 = 51%, 3286 participants, 37 RCTs, moderate-certainty evidence) and over one to two years (MD -0.93 kg, 95% CI -1.81 to -0.04, I2 = 40%, 1805 participants, 14 RCTs, moderate-certainty evidence); as well as change in DBP and LDL cholesterol over one to two years. The evidence is very uncertain about whether there is a difference in the number of participants per group with weight loss of at least 5% at one year (risk ratio (RR) 1.11, 95% CI 0.94 to 1.31, I2 = 17%, 137 participants, 2 RCTs, very low-certainty evidence).  In overweight and obese participants with T2DM: low-carbohydrate weight-reducing diets compared to balanced-carbohydrate weight-reducing diets (weight-reducing phases only) probably result in little to no difference in change in body weight over three to six months (MD -1.26 kg, 95% CI -2.44 to -0.09, I2 = 47%, 1114 participants, 14 RCTs, moderate-certainty evidence) and over one to two years (MD -0.33 kg, 95% CI -2.13 to 1.46, I2 = 10%, 813 participants, 7 RCTs, moderate-certainty evidence); as well in change in DBP, HbA1c and LDL cholesterol over 1 to 2 years. The evidence is very uncertain about whether there is a difference in the number of participants per group with weight loss of at least 5% at one to two years (RR 0.90, 95% CI 0.68 to 1.20, I2 = 0%, 106 participants, 2 RCTs, very low-certainty evidence).  Evidence on participant-reported adverse effects was limited, and we could not draw any conclusions about these.  AUTHORS' CONCLUSIONS: There is probably little to no difference in weight reduction and changes in cardiovascular risk factors up to two years' follow-up, when overweight and obese participants without and with T2DM are randomised to either low-carbohydrate or balanced-carbohydrate weight-reducing diets.

Food Liking but Not Wanting Decreases after Controlled Intermittent or Continuous Energy Restriction to ≥5% Weight Loss in Women with Overweight/Obesity

Food reward (i.e., liking and wanting) has been shown to decrease after different types of weight management interventions. However, it is unknown whether specific dietary modalities (continuous (CER) vs. intermittent (IER) energy restriction) have differing effects on liking and implicit wanting after weight loss (WL) and whether these changes are sustained after 1-year of no-contact. Women with overweight or obesity (age 18–55 years) were randomly allocated to controlled-feeding CER (25% daily energy restriction) or IER (alternating ad libitum and 75% energy restriction days). Study visits were conducted at baseline, post-WL (to ≥5% WL within 12 weeks) and 1-year post-WL. The main outcomes were liking and implicit wanting for 4 categories of common food varying in fat and taste assessed by the Leeds Food Preference Questionnaire. Linear mixed models were conducted on the 30 participants achieving ≥5% WL and 15 returners. After an initial WL of −5.1 ± 0.2 kg, after 1-year 2.6 ± 0.5 kg were regained. Liking but not wanting decreased after WL. Food reward after 1-year did not differ from baseline, but the high loss to follow-up prevents generalization. IER and CER did not differ in their effects on food reward during WL or at 1-year follow-up.

The Psychology of Food Cravings: the Role of Food Deprivation

PURPOSE OF REVIEW

Dieting is often blamed for causing food cravings. Such diet-induced cravings may be mediated by physiological (e.g., nutritional deprivation) or psychological (e.g., ironic effects of food thought suppression) mechanisms. However, this notion is often based on cross-sectional findings and, thus, the causal role of food deprivation on food cravings is unclear.

RECENT FINDINGS

Experimental studies suggest that a short-term, selective food deprivation seems to indeed increase cravings for the avoided foods. However, experimental studies also show that food craving can be understood as a conditioned response that, therefore, can also be unlearned. This is supported by intervention studies which indicate that long-term energy restriction results in a reduction of food cravings in overweight adults. Dieting's bad reputation for increasing food cravings is only partially true as the relationship between food restriction and craving is more complex. While short-term, selective food deprivation may indeed increase food cravings, long-term energy restriction seems to decrease food cravings, suggesting that food deprivation can also facilitate extinction of conditioned food craving responses.

COVID-19 Lockdown and Changes of the Dietary Pattern and Physical Activity Habits in a Cohort of Patients with Type 2 Diabetes Mellitus

The COVID-19 lockdown clearly affected the lifestyle of the population and entailed changes in their daily habits, which involved potential health consequences, especially on patients with Type 2 Diabetes Mellitus (T2DM). We aimed to examine the impact of the lockdown caused by COVID-19 pandemic on both nutrition and exercise habits, as well as the psychological effects in patients with T2DM, compared to their usual diet and physical activity level previous to the complete home confinement. We also intended to analyse any potential variables that may have influenced these lifestyle modifications. A Food Frequency Questionnaire (FFQ), Physical Activity Questionnaire (IPAQ), Food Craving Questionnaire-State (FCQ-S) and Food Craving Questionnaire-Trait (FCQ-T) were used. Our results showed an increase in vegetable, sugary food and snack consumption. An association between levels of foods cravings and snack consumption was also found. Data also showed a high percentage of physical inactivity before the COVID-19 lockdown, which was exacerbated during the home confinement. These findings emphasise the great importance to do further research with larger study samples to analyse and explore dietary habits and to develop public health policies to promote a healthy lifestyle in terms of diet and physical activity in these patients, especially after this strict period of lockdown.

Dietary protein and appetite sensations in individuals with overweight and obesity: a systematic review

PURPOSE

This systematic review aimed to synthesize the available evidence on the effects of a high-protein diet on appetite sensations in individuals with overweight and obesity.

METHODS

Two authors independently conducted literature searches, study selection, design of the method, and quality appraisal. The main inclusion criteria were studies involving protocols that present a protein intake greater than 1.2 g/kg/day or 25% of the total daily energy content compared to a normal protein diet, i.e., 0.8-1.2 g/kg/day or 15%-20% of the total energy content. Studies that evaluated test meals or diet within a period of less than 7 days and participants with diabetes, cancer, or other specific conditions were excluded from this review. The literature search was updated until November 2019 using the main databases available.

RESULTS

Of a total of 4191 records, ten articles met the inclusion criteria and included a total of 1079 subjects. In six studies, participants experienced enhanced fullness or satiety in response to a high-dietary protein intake, of which four studies had an intervention period of 10-12 weeks.

CONCLUSION

Our results suggest that among individuals with overweight or obesity, higher dietary protein intake may influence appetite sensations by enhancing fullness or satiety. The low level of evidence, due to the heterogeneity of the protocols and the high risk of bias, highlights the need for further studies to confirm these results.

Twenty Years of the Food Cravings Questionnaires: a Comprehensive Review

Purpose of Review

The Food Cravings Questionnaires (FCQs; Cepeda-Benito, Gleaves, Williams, & Erath, 2000) are among the most widely used instruments for measuring food cravings. In addition to the Food Cravings Questionnaire–Trait (FCQ–T) and the Food Cravings Questionnaire–State (FCQ–S), several modified versions have been developed as well. For their 20th anniversary, this article provides a comprehensive description of the FCQs and reviews studies on their psychometric properties and correlates.

Recent Findings

The FCQs and their modified versions have excellent internal reliability. Expectedly, the FCQ–T (and its derivatives) has higher retest-reliability than the FCQ–S as the FCQ–S is sensitive to situational changes such as food deprivation and food intake. However, while the FCQ–T is largely unaffected by such momentary states, it is also sensitive to change during weight-loss treatments and other interventions. Factor structure of the FCQ–T and FCQ–S has only partially been replicated. Construct validity of the FCQs is supported by experimental and longitudinal studies that measured food craving and food consumption in the laboratory and with ecological momentary assessment.

Summary

Numerous studies support reliability and validity of the FCQs and their modified versions, yet findings about their factor structures are inconsistent. Thus, using total scores or the short versions of the FCQs may be preferable.

Changes in Food Cravings and Eating Behavior after a Dietary Carbohydrate Restriction Intervention Trial

Compared to low-fat diets, low-carbohydrate (CHO) diets cause weight loss (WL) over a faster time frame; however, it is unknown how changes in food cravings and eating behavior contribute to this more rapid WL in the early phases of dieting. We hypothesized that reductions in food cravings and improved eating behaviors would be evident even after a relatively short (4-week) duration of CHO-restriction, and that these changes would be associated with WL. Adult participants (n = 19, 53% males, mean ± SD: BMI = 34.1 ± 0.8 kg/m²; age 40.6 ± 1.9 years) consumed a CHO-restricted diet (14% CHO, 58% fat, 28% protein) for 4 weeks. Before and after the intervention, specific and total cravings were measured with the Food Craving Inventory (FCI) and eating behaviors assessed with the Three-Factor Eating questionnaire. Food cravings were significantly reduced at week 4, while women had significantly greater reductions in sweet cravings than men. Dietary restraint was significantly increased by 102%, while disinhibiton and hunger scores were reduced (17% and 22%, respectively, p < 0.05). Changes in cravings were unrelated to changes in body weight except for the change in high-fat cravings where those who lost the most weight experienced the least reductions in fat cravings (r = −0.458, p = 0.049). Changes in dietary restraint were inversely related to several FCI subscales. A short-term, low-CHO diet was effective in reducing food cravings. These data suggest that in subjects that have successfully lost weight on a low-CHO diet, those who craved high-fat foods at the onset were able to satisfy their cravings—potentially due to the high-fat nature of this restricted diet.

Dietary modifications for weight loss and weight loss maintenance

Worldwide obesity rates remain at a rise, and to treat obesity is at the top of the global public health agenda. In 2013, the AHA/ACC/TOS obesity management guidelines were published, in essence suggesting that any dietary scheme seems to be effective for weight loss, as long as it can induce a sustainable energy deficit. In the present review, we update and critically discuss available information regarding dietary modifications for weight loss and weight loss maintenance, published after the 2013 guidelines. Regarding weight loss, we found no proof to support that a single dietary scheme, be it nutrient-, food group- or dietary pattern- based, is more efficacious of the other for achieving weight loss. For weight loss maintenance, published interventions point towards the same direction, although inconclusively. Most research explores the effect of weight loss regimes on weight loss maintenance and not the effect of the diet during weight loss maintenance, and this literature gap should be more thoroughly investigated.

Examining the Effects of Mindful Eating Training on Adherence to a Carbohydrate-Restricted Diet in Patients With Type 2 Diabetes (the DELISH Study): Protocol for a Randomized Controlled Trial

Background

Diet patterns have a profound influence on glycemic control for individuals with type 2 diabetes mellitus (T2DM), and craving-related eating is an important obstacle to dietary adherence. A growing body of research suggests that carbohydrate-restricted (CR) diets can improve glycemic control and reduce medication dependence in T2DM. However, limited data speak to the effects of long-term adherence to CR diets. Mindful eating training has been shown to reduce craving-related eating in overweight populations but has yet to be examined as a behavioral support for dietary adherence in T2DM. This trial examines behavioral mechanisms, particularly craving-related eating, through which mindful eating training might improve adherence to CR dietary recommendations in T2DM. This will clarify the importance of focusing on craving-related eating in the optimization of dietary adherence interventions.

Objective

The aim of this trial is to determine whether providing training in mindful eating increases adherence to a CR dietary recommendation in T2DM.

Methods

We are randomizing 60 participants to receive a CR diet with or without mindful eating training (12-week group intervention) and are following participants for 12 weeks after intervention completion. We hypothesize that participants who receive mindful eating training (relative to those who do not) will demonstrate greater adherence to the CR diet.

Results

Our primary outcome is change in craving-related eating, as assessed using an ecological momentary assessment mobile phone–based platform. Secondary behavioral pathway outcomes include changes in stress-related eating, impulsivity, glycemic control, weight change, dietary adherence, and resumption of dietary adherence after dietary nonadherence.

Conclusions

This theory-driven trial will shed light on the impact of mindfulness training on mechanisms that may impact dietary adherence in T2DM.

Trial Registration

ClinicalTrials.gov NCT03207711; https://clinicaltrials.gov/ct2/show/NCT03207711 (Archived by WebCite at http://www.webcitation.org/73pXscwaU)