Daily Energy Restriction Research Articles

A qualitative exploration of behaviour change and maintenance experience in people with overweight or obesity in a dietary intervention.

This qualitative study aimed to explore the experiences of participants who were enrolled in 6-month controlled weight loss interventions with 2-month follow-up to better understand the process of behaviour change and maintenance. Fifteen participants who completed or dropped out from either a daily energy restriction or intermittent fasting group were recruited using maximum variation purposive sampling. In-depth, semi-structured interviews were conducted at the 2-month follow-up phase. All interviews were transcribed and analysed using thematic analysis, guided by behaviour change models including transtheoretical model, social cognitive theory and integrated model of change. Participants following both diets showed similar behaviour change patterns. Their first motivations were mostly external and relied on 'accountability' to adhere to the diet when initiating the dietary changes. Participants highlighted the importance of frequent reviews and monitoring in assisting their adherence. This feedback system promoted the development of self-efficacy and internalised motivation to encourage an 'ownership'. Participants who transitioned successfully from relying on accountability to take 'ownership' of the intervention were more capable of tackling challenges and tailoring their diet to form a new routine for long-term maintenance. External motivations were key to initiate while internalised motivations were more important to sustain the behaviour change. Health professionals can assist this process through routine monitoring and feedback processes in clinical practice.

Dietary Patterns and Meal Timing to Achieve a Healthy Body Weight and Promote Cardiometabolic Health: What Is the Evidence?

Dietary Patterns and Meal Timing to Achieve a Healthy Body Weight and Promote Cardiometabolic Health: What Is the Evidence?

The effect of intermittent fasting diets on body weight and composition.

This study was carried out to determine and compare the effects on anthropometric measurements of the Mediterranean Diet (MD) with daily energy restriction and four different intermittent fasting diets (IFD), which were created as an alternative to MD and gained popularity. 360 people aged 18-65 years, with body mass index (BMI) between 27 and 35kg/m2 participated to the study. Demographic information, anthropometric measurements, physical activity and food consumption records were obtained by the researcher through weekly face-to-face interviews. The study lasted for 13 weeks, the first of which was a trial. Statistical significance level was accepted as 0.05. Participants were randomly assigned to 5 equal groups: Mediterranean Diet (MD), Week on Week off (WOWO), 6-Hour Time-Restricted Eating (TRE-6), 8-Hour Time-Restricted Eating (TRE-8), Alternative Day Diet (ADD). Of the 360 people who participated in the study, 32 (2 TRE-6, 7 WOWO, 1 MD, 16 ADD, 6 TRE-8) dropped out after the trial week. It was determined that throughout the study, body weights, BMI, arm circumferences and waist circumferences in all groups decreased significantly. However, trends in changes in body weights and BMIs did not differ between groups. While the energy, carbohydrate, protein and fat intakes of the participants did not change significantly during the study, fiber consumption increased considerably in the MD and WOWO groups. It was observed that IFD were not superior to MD in terms of anthropometric measurements. The health effects and long-term consequences are not clear for IFD, unlike MD. For these reasons, it is thought that the most effective nutritional therapy that can be preferred for healthy weight loss is the energy-restricted MD model.

A randomized controlled trial to isolate the effects of fasting and energy restriction on weight loss and metabolic health in lean adults.

Intermittent fasting may impart metabolic benefits independent of energy balance by initiating fasting-mediated mechanisms. This randomized controlled trial examined 24-hour fasting with 150% energy intake on alternate days for 3 weeks in lean, healthy individuals (0:150; n = 12). Control groups involved a matched degree of energy restriction applied continuously without fasting (75% energy intake daily; 75:75; n = 12) or a matched pattern of fasting without net energy restriction (200% energy intake on alternate days; 0:200; n = 12). Primary outcomes were body composition, components of energy balance, and postprandial metabolism. Daily energy restriction (75:75) reduced body mass (-1.91 ± 0.99 kilograms) almost entirely due to fat loss (-1.75 ± 0.79 kilograms). Restricting energy intake via fasting (0:150) also decreased body mass (-1.60 ± 1.06 kilograms; P = 0.46 versus 75:75) but with attenuated reductions in body fat (-0.74 ± 1.32 kilograms; P = 0.01 versus 75:75), whereas fasting without energy restriction (0:200) did not significantly reduce either body mass (-0.52 ± 1.09 kilograms; P ≤ 0.04 versus 75:75 and 0:150) or fat mass (-0.12 ± 0.68 kilograms; P ≤ 0.05 versus 75:75 and 0:150). Postprandial indices of cardiometabolic health and gut hormones, along with the expression of key genes in subcutaneous adipose tissue, were not statistically different between groups (P > 0.05). Alternate-day fasting less effectively reduces body fat mass than a matched degree of daily energy restriction and without evidence of fasting-specific effects on metabolic regulation or cardiovascular health.

Avaliação do protocolo de Jejum Intermitente no tratamento de sobrepeso e obesidade: uma revisão integrativa

A obesidade, é o acúmulo excessivo de gordura corporal, que acarreta prejuízos à saúde dos indivíduos, tais como dificuldade respiratória, problemas dermatológicos e distúrbios do aparelho locomotor e favorece o surgimento de doenças crônicas não transmissíveis potencialmente letais. São várias as estratégias e ferramentas ao qual o profissional nutricionista dispõe para realização do tratamento de sobrepeso e obesidade, dentre elas, o jejum intermitente, que é um protocolo de dieta que visa alternar períodos de ingestão alimentar e jejum. O objetivo é fazer com que o corpo utilize os estoques de gordura e com isso haja uma perda de massa gorda, os períodos em que a alimentação é permitida são chamados de janelas de alimentação. O estudo é uma revisão integrativa da literatura em Nutrição, com o objetivo de revisar os estudos que avaliaram a aplicabilidade do protocolo de jejum intermitente no tratamento de sobrepeso e obesidade em indivíduos adultos, com ênfase aos aspectos de perda de peso e melhora dos marcadores biológicos de saúde. Foram pesquisados e examinados 10 artigos científicos com maior número de produção no ano de 2018. Os artigos analisados apontaram que a Restrição Energética Intermitente (IER) é uma alternativa dietética eficaz para promover a perda de peso em adultos com sobrepeso / obesidade no curto prazo, desta forma, pode ser utilizado no tratamento de forma segura. Os resultados mostram que o IER pode resultar em perda de peso em adultos com sobrepeso e obesidade comparável a Restrição Energética Diária (DER) tradicional.

The role of intermittent fasting and meal timing in weight management and metabolic health.

Obesity remains a major public health concern and intermittent fasting is a popular strategy for weight loss, which may present independent health benefits. However, the number of diet books advising how fasting can be incorporated into our daily lives is several orders of magnitude greater than the number of trials examining whether fasting should be encouraged at all. This review will consider the state of current understanding regarding various forms of intermittent fasting (e.g. 5:2, time-restricted feeding and alternate-day fasting). The efficacy of these temporally defined approaches appears broadly equivalent to that of standard daily energy restriction, although many of these models of intermittent fasting do not involve fed-fasted cycles every other 24 h sleep-wake cycle and/or permit some limited energy intake outside of prescribed feeding times. Accordingly, the intervention period therefore may not regularly alternate, may not span all or even most of any given day, and may not even involve absolute fasting. This is important because potentially advantageous physiological mechanisms may only be initiated if a post-absorptive state is sustained by uninterrupted fasting for a more prolonged duration than applied in many trials. Indeed, promising effects on fat mass and insulin sensitivity have been reported when fasting duration is routinely extended beyond sixteen consecutive hours. Further progress will require such models to be tested with appropriate controls to isolate whether any possible health effects of intermittent fasting are primarily attributable to regularly protracted post-absorptive periods, or simply to the net negative energy balance indirectly elicited by any form of dietary restriction.

The safety and efficacy of weight loss via intermittent fasting or standard daily energy restriction in adults with type 1 diabetes and overweight or obesity: A pilot study

ObjectiveA pilot study to examine the safety and efficacy of weight loss via intermittent fasting or continuous energy restriction in adults with type 1 diabetes and overweight or obesity. Research design and methodsTen participants with type 1diabetes and overweight or obesity (8 women, 2 men) were randomised to either severe energy restriction (2510 kilojoules per day) on two 24-hour periods per week with 5 days per week of eating to appetite, or continuous moderate energy restriction (30% relative to weight maintenance energy needs) for 12 weeks. Participants were followed to 12 months. ResultsThere were no adverse events during the study, and rates of hypoglycaemia were unchanged. Body weight was reduced from baseline (P < 0.05) by both intermittent fasting (−7.0%, range −5.2% to −8.0%) and continuous energy restriction (−3.9%, range −1.0% to −11.1%). Trunk fat was also reduced by these two interventions (P < 0.05) (−12.2%, range −1.0% to −15.3% and −10.1%, range 2.3% to −10.7%, respectively). Blood pressure and circulating concentrations of HbA1c and lipids remained unchanged from baseline. There were no between group differences in these outcomes. ConclusionThese findings suggest that both intermittent fasting or continuous energy restriction are safe and effective weight loss approaches for people with type 1 diabetes and overweight or obesity.

Randomized Trial of a High Protein, Partial Meal Replacement Program with or without Alternate Day Fasting: Similar Effects on Weight Loss, Retention Status, Nutritional, Metabolic, and Behavioral Outcomes.

Higher-protein diets, meal replacements, and greater early weight loss have separately been associated with greater weight loss. We compared a high-protein, meal replacement program with daily energy restriction (DER) to one which provided greater energy restriction adding alternate day fasting (ADF + DER; alternating days of modified-fasting and DER plus 1 ad libitum day/week) on retention, weight loss, physiological, nutritional, and behavioral markers. Participants were randomized to ADF + DER or DER for 16 weeks (n = 162, age 40 ± 8 years BMI 36 ± 6 kg/m2 (Mean ± SD)) plus 8 weeks weight maintenance. At week 16 weight change was −10.7 ± 0.5 kg and −11.2 ± 0.6 kg in ADF + DER and DER groups (treatment NS). Fat mass, visceral adipose tissue, and lean mass (p < 0.05) were similarly reduced between treatments. Weight loss was sustained to 24 weeks (treatment NS). Fasting LDL-cholesterol, triglycerides, insulin, hsCRP, glucose, and blood pressure all improved (p < 0.05; treatment NS). Transferrin saturation, ferritin, serum zinc, folate, and B12 improved (p < 0.05; treatment NS). Plasma thiamine and vitamin D levels decreased, reflecting lower carbohydrate intakes and seasonal changes, respectively. Food cravings, quality of life, and mood improved (treatment NS). Energy, fatigue, and pain improved slightly more in DER (p < 0.05). This study supports the use of higher protein, meal replacement programs with or without ADF in weight management.

Effect of a high-egg diet on cardiometabolic risk factors in people with type 2 diabetes: the Diabetes and Egg (DIABEGG) Study—randomized weight-loss and follow-up phase

Some country guidelines recommend that people with type 2 diabetes (T2D) limit their consumption of eggs and cholesterol. Our previously published 3-mo weight-maintenance study showed that a high-egg (≥12 eggs/wk) diet compared with a low-egg diet (<2 eggs/wk) did not have adverse effects on cardiometabolic risk factors in adults with T2D. The current study follows the previously published 3-mo weight-maintenance study and assessed the effects of the high-egg compared with the low-egg diets as part of a 3-mo weight-loss period, followed by a 6-mo follow-up period for a total duration of 12 mo. Participants with prediabetes or T2D (n=128) were prescribed a 3-mo daily energy restriction of 2.1 MJ and a macronutrient-matched diet and instructed on specific types and quantities of foods to be consumed, with an emphasis on replacing saturated fats with monounsaturated and polyunsaturated fats. Participants were followed up at the 9- and 12-mo visits. From 3 to 12 mo, the weight loss was similar (high-egg compared with low-egg diets: -3.1±6.3 compared with -3.1±5.2 kg; P=0.48). There were no differences between groups in glycemia (plasma glucose, glycated hemoglobin, 1,5-anhydroglucitol), traditional serum lipids, markers of inflammation (high-sensitivity C-reactive protein, interleukin 6, soluble E-selectin), oxidative stress (F2-isoprostanes), or adiponectin from 3 to 12 mo or from 0 to 12 mo. People with prediabetes or T2D who consumed a 3-mo high-egg weight-loss diet with a 6-mo follow-up exhibited no adverse changes in cardiometabolic markers compared with those who consumed a low-egg weight-loss diet. A healthy diet based on population guidelines and including more eggs than currently recommended by some countries may be safely consumed. This trial is registered at http://www.anzctr.org.au/ as ACTRN12612001266853.

Effect of diet with carbohydrate but without daily energy restriction on serum glucose, lactate, and selected mineral and lipid levels in streptozotocin-induced experimental diabetic rats

Objective: Type I diabetes is a disease characterised by an extreme reduction in serum insulin levels. Diet and exercise have gained considerable attention in the treatment of diabetes. Therefore, this study was carried out to investigate the effect of diet with carbohydrate but without daily energy restriction on various metabolites (glucose, triglycerides, cholesterol, lactate), some electrolytes (Ca, Mg, Na, K, P, Cl) and essential metals (Mn, Co, Cu, Se, Zn, Fe) in the blood of rats with streptozotocin-induced diabetes.Materials and methods: Thirty-three male rats were divided into four groups of standard rat diet (SR)-fed control, SR-diet fed diabetics, low carbohydrate-standard protein-high fat (LCSPHF) diet-fed diabetics, and very low carbohydrate-high protein-high fat (VLCHPHF) diet-fed diabetics. Diabetes was induced by an i.p. injection of 50 mg/kg streptozotocin. The rats were fed with the specially prepared diets for 28 days.Results: The decreased-serum Cl and the increased-serum glucose levels were only the difference between the controls and SR diet-fed diabetic rats regarding to measured parameters. Lowering carbohydrate and increasing fat ratio in diet caused an increase in serum cholesterol and triglyceride levels leading to an increased-serum Fe and Ca, and decreased-serum Na and Cu levels in diabetic rats.Conclusion: The serum mineral changes should be taken into consideration together with the changes in serum glucose, cholesterol, and triglyceride levels for the secondary complications of diabetes mellitus.

Assessing the evidence for weight loss strategies in people with and without type 2 diabetes.

This review will examine topical issues in weight loss and weight maintenance in people with and without diabetes. A high protein, low glycemic index diet would appear to be best for 12-mo weight maintenance in people without type 2 diabetes. This dietary pattern is currently being explored in a large prevention of diabetes intervention. Intermittent energy restriction is useful but no better than daily energy restriction but there needs to be larger and longer term trials performed. There appears to be no evidence that intermittent fasting or intermittent severe energy restriction has a metabolic benefit beyond the weight loss produced and does not spare lean mass compared with daily energy restriction. Meal replacements are useful and can produce weight loss similar to or better than food restriction alone. Very low calorie diets can produce weight loss of 11-16 kg at 12 mo with persistent weight loss of 1-2 kg at 4-6 years with a very wide variation in long term results. Long term medication or meal replacement support can produce more sustained weight loss. In type 2 diabetes very low carbohydrate diets are strongly recommended by some groups but the long term evidence is very limited and no published trial is longer than 12 mo. Although obesity is strongly genetically based the microbiome may play a small role but human evidence is currently very limited.

Alternate-day fasting protects the livers of mice against high-fat diet–induced inflammation associated with the suppression of Toll-like receptor 4/nuclear factor κB signaling

Because of unhealthy lifestyles, a large number of people are suffering from hepatic lipid accumulation and nonalcoholic steatohepatitis. Energy restriction (ER) is an effective nutritional intervention for preventing chronic disease. However, poor compliance with continuous ER limits its effectiveness. As an alternative to daily ER, alternate-day fasting (ADF) may be more effective. We hypothesized that ADF would improve obesity, hyperglycemia, and insulin resistance and protect the liver against high-fat diet (HFD)–induced steatosis and inflammation. In this study, we used C57BL/6 mice to test the beneficial effects of ADF. Thirty male 6-week-old C57BL/6 mice were divided into 3 groups (10 per group, total N = 30): 1 group was fed chow diet, the second was fed HFD ad libitum, and the third group was submitted to ADF. The mice in the third group were fed the HFD ad libitum every other day and fasted the following day. After 12 months, the mice submitted to ADF exhibited reduced body weights and fasting glucose levels and improved insulin resistance and hepatic steatosis compared with continuous HFD-fed mice. In addition, the serum transaminase levels in the mice of the ADF group were lower than those of the HFD group. Moreover, the ADF regimen suppressed the expression levels of Toll-like receptor 4 and nuclear factor κB protein in the liver and suppressed the inflammatory pathway genes interleukin 1β, tumor necrosis factor α, and serum amyloid A. These finding indicate that long-term ADF protects mouse livers against HFD-induced hepatic steatosis and hepatocellular damage associated with the suppression of Toll-like receptor 4/nuclear factor κB signaling.

Intermittent energy restriction and weight loss: a systematic review.

Intermittent energy restriction (IER) is an eating pattern of regular daily periods of restricted energy intake followed by periods of unrestricted energy intake. This is gaining prominence as an alternative weight-loss strategy to daily energy restriction (DER). The aim of this systematic review was to determine the effectiveness of IER on weight loss in overweight and obese adults and compare this with DER. A systematic literature search was conducted using the CINAHL, Embase, Medline, PsycINFO, Cochrane and Scopus databases. Eight studies that assigned overweight or obese adults to IER or to a DER 'control' were deemed eligible for inclusion. All studies reported significant weight loss for IER groups. Average weight loss was approximately 0.2-0.8 kg per week. IER resulted in comparable weight loss to DER when overall energy restriction remained similar between diets. The majority of studies that reported body composition outcomes have shown equal efficacy for fat mass, fat-free mass and waist circumference. Weight loss was achieved in overweight and obese adults following IER and this loss was comparable to a DER diet. IER may be an effective alternative strategy for health practitioners to promote weight loss for selected overweight and obese people.

Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review protocol.

Are intermittent fasting interventions an effective treatment for overweight and obesity in adults, when compared to usual care treatment (continuous daily energy restriction - reduced calorie diet) or no treatment (ad libitum diet)? Overweight and obesity (classified as Body Mass Index [BMI] of greater than or equal to 25 and 30 respectively) is a global public health concern, with more than 1.9 billion adults worldwide being overweight in 2014 (over 600 million of whom are obese), and resulting in more deaths than underweight. A raised BMI in adulthood is associated with an increased risk of developing a number of chronic diseases which include diabetes, cardiovascular disease, muscular skeletal disorders and some cancers. In addition to this substantial impact on individual health and well being, there are also significant wider costs, for example, in England the annual direct cost to the national health service for treating overweight, obesity and associated morbidity is estimated at over £5 billion pounds, with costs to the wider economy estimated at £27 billion. Therefore effective weight management is essential.As overweight and obesity results from an accumulation of excess body fat arising from an energy imbalance - consuming more energy (kcal) than is expended - the majority of weight management approaches center around behaviors to address this imbalance, i.e. reducing energy intake through caloric restriction and increasing energy expenditure through physical activity. However, the aetiology of overweight and obesity is highly complex, involving an interplay of biological, psychological, societal and environmental drivers. Consequently, effective weight management is challenging, and whilst there exists a plethora of available weight loss programs, not all are comprehensively evaluated and compared, and many weight loss attempts result in weight regain and poor long term results. It is therefore vitally important to review the effectiveness of all new approaches to support an evidence-based approach to weight management.Intermittent fasting (IF), also known as alternate day fasting (ADF), periodic fasting or intermittent energy restriction (IER) is a relatively new dietary approach to weight management that involves interspersing normal daily caloric intake with a short period of severe calorie restriction/fasting. In terms of the possible underlying biological benefits of intermittent fasting, there is some evidence, predominantly from animal studies, to demonstrate beneficial effects on weight loss and cardio-metabolic risk factors. Whilst the underpinning mechanistic evidence is limited, there is some evidence to suggest that the benefits may be explained mechanistically through fat utilization and nutritional stress. However current National Institute for Health and Care Excellence (NICE) guidance on the treatment of adult obesity does not recommend the routine use of very low calorie diets (VLCD) (defined as a hypocaloric diet of 800 or less kcal/day) for the treatment of adult obesity. The National Institute for Health and Care Excellence states that this approach should only be recommended if there is a clinical rationale for rapid weight loss and must be nutritionally complete, part of a multi-component weight management strategy, including ongoing support, and should be undertaken for a maximum of 12 weeks (followed continuously or intermittently). Furthermore, the British Dietetic Association raises concerns that rapid weight loss associated with fasting may largely be due to loss of water and glycogen rather than fat, and may result in fatigue, dizziness and low energy levels. Essentially IF involves the intermittent use of a VLCD, and there remain questions about the side effects of this approach, whether there is an optimal fasting pattern or calorie limit, and how sustainable it is for long term weight management.Intermittent fasting has recently gained much popularity following significant media attention. In the UK this dietary approach reached mainstream after a BBC Horizon documentary aired in August 2012, featured an IF approach called the 5:2 diet, which involves five days of regular eating patterns interchanged with two days of fasting (max 500kcal for women and 600kcal for men). However other IF patterns are used such as alternate day fasting. Despite the recent popularity of intermittent fasting and associated weight loss claims, the supporting evidence base in humans remains small and there is only one published systematic review examining the health benefits of this approach. However the aim of this review was to examine the impact of this intervention on wider health benefits (not specifically as a treatment approach for overweight and obesity), and did not provide a comprehensive methodology or meta-analysis of RCT data. This proposed review will hence address these gaps in the evidence base.

The effect of intermittent energy and carbohydrate restrictionv. daily energy restriction on weight loss and metabolic disease risk markers in overweight women

Intermittent energy restriction may result in greater improvements in insulin sensitivity and weight control than daily energy restriction (DER). We tested two intermittent energy and carbohydrate restriction (IECR) regimens, including one which allowed ad libitum protein and fat (IECR+PF). Overweight women (n 115) aged 20 and 69 years with a family history of breast cancer were randomised to an overall 25 % energy restriction, either as an IECR (2500-2717 kJ/d, < 40 g carbohydrate/d for 2 d/week) or a 25 % DER (approximately 6000 kJ/d for 7 d/week) or an IECR+PF for a 3-month weight-loss period and 1 month of weight maintenance (IECR or IECR+PF for 1 d/week). Insulin resistance reduced with the IECR diets (mean - 0·34 (95% CI - 0·66, - 0·02) units) and the IECR+PF diet (mean - 0·38 (95% CI - 0·75, - 0·01) units). Reductions with the IECR diets were significantly greater compared with the DER diet (mean 0·2 (95% CI - 0·19, 0·66) μU/unit, P= 0·02). Both IECR groups had greater reductions in body fat compared with the DER group (IECR: mean - 3·7 (95% CI - 2·5, - 4·9) kg, P= 0·007; IECR+PF: mean - 3·7 (95% CI - 2·8, - 4·7) kg, P= 0·019; DER: mean - 2·0 (95% CI - 1·0, 3·0) kg). During the weight maintenance phase, 1 d of IECR or IECR+PF per week maintained the reductions in insulin resistance and weight. In the short term, IECR is superior to DER with respect to improved insulin sensitivity and body fat reduction. Longer-term studies into the safety and effectiveness of IECR diets are warranted.

P3-09-02: Intermittent Dietary Carbohydrate Restriction Enables Weight Loss and Reduces Breast Cancer Risk Biomarkers.

Abstract Background: Energy restriction is a potential strategy for breast cancer prevention but is difficult to achieve and maintain. We found that intermittent energy restriction (2 days strict dieting week) is comparable to the standard approach of moderate daily restriction for weight loss and marginally better for improving insulin sensitivity, but no easier to follow1. In this follow on study we wished to test whether 2 novel intermittent low carbohydrate/low energy diets were feasible and easier to follow than a standard daily energy restriction. Design: Randomised comparison of 3 dietary types over 4 months in 115 overweight or obese (mean body mass index 31.0 [±5.3 SD] kg/m2) women at increased risk of breast cancer (lifetime risk &amp;gt; 1 in 6). Diets: 1. A restricted low carbohydrate diet (RLCD): 650 kcal and &amp;lt;50g carbohydrate / day for 2 days per week 2. Ad lib low carbohydrate diet (ALCD): &amp;lt;50g / day for 2 days per week with other food types (e.g. protein) ad lib 3. A standard daily restricted Mediterranean diet (DRMD): ∼ 1500kcal/day for 7 days per week Methods: Weight, anthropometrics, blood markers for breast cancer; insulin resistance, oxidative stress markers, leptin, adiponectin, lipids, inflammatory markers IGF-1 were assessed at baseline, 1, 3 and 4 months. Results: 88/114 completed the study (77%, drop outs 6 RLCD, 8 ALCD 12 DRMD). Last observation carried forward analyses show both intermittent low carbohydrate diets were superior to standard daily restriction for reducing weight and body fat: mean (95% confidence interval [CI]) change in body fat for RLCD was −4.3 (−5.6 to −3.0) kg, for ALCD −4.1 (−5.2 to −3.1) kg vs. −2.4 (−3.4 to −1.2) kg for DRMD (P value for difference between groups = 0.02). The intermittent groups had greater improvement in insulin resistance: mean (95% CI) change for RLCD was −22 (−35 to −11) %, ALCD −14 (−27 to −5%) % vs. −4 (−16 to 9) % for DRMD (P = 0.02). Other biomarkers are being assayed currently. Conclusion: Greater weight loss, fewer drop outs and greater reductions in insulin resistance with the novel intermittent low carbohydrate diets indicate that these are alternative approaches for energy restriction for potentially reducing risk of breast cancer and other diseases. Reference: 1Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G et al. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int.J Obes (Lond) 35; 714–27, 2011. This study is funded by the Genesis Breast Cancer Prevention Appeal: www.genesisuk.org Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-09-02.

Dietary and physical activity adaptations to alternate day modified fasting: implications for optimal weight loss.

BackgroundAlternate day modified fasting (ADMF) is an effective strategy for weight loss in obese adults.ObjectiveThe objective of this study was to examine the dietary and physical activity adaptations that occur during short-term ADMF, and to determine how these modulations affect rate of weight loss.MethodsSixteen obese subjects (12 women/4 men) completed a 10-week trial consisting of 3 phases: 1) 2-week control phase, 2) 4-week ADMF controlled feeding phase, and 3) 4-week ADMF self-selected feeding phase.ResultsBody weight decreased (P < 0.001) by 5.6 ± 1.0 kg post-treatment. Energy intake on the fast day was 26 ± 3% of baseline needs (501 ± 28 kcal/d). No hyperphagic response occurred on the feed day (95 ± 6% of baseline needs consumed, 1801 ± 226 kcal/d). Daily energy restriction (37 ± 7%) was correlated to rate of weight loss (r = 0.42, P = 0.01). Dietary fat intake decreased (36% to 33% of kcal, P < 0.05) with dietary counseling, and was related to rate of weight loss (r = 0.38, P = 0.03). Hunger on the fast day decreased (P < 0.05) by week 2, and remained low. Habitual physical activity was maintained throughout the study (fast day: 6416 ± 851 steps/d; feed day: 6569 ± 910 steps/d).ConclusionThese findings indicate that obese subjects quickly adapt to ADMF, and that changes in energy/macronutrient intake, hunger, and maintenance of physical activity play a role in influencing rate of weight loss by ADMF.

Effects of moderate energy restriction on light and medium hybrid laying hens

1. Two light and two medium hybrid strains were fed, from 32 to 48 and from 56 to 68 weeks of age, ad libitum or approximately 89%, 85% and 80% of the ad libitum intake; from 48 to 56 weeks all the birds were fed ad libitum. 2. A daily energy restriction of 11 to 13% in the first period, resulted in the rate of lay being depressed by nearly 11% points for one light hybrid strain and by more than 5% points for the medium hybrids while the corresponding depressions in egg weight were 4% and 2%. 3. During rehabilitation egg output was similar for controls and restriction treatments, though that of the most severely restricted groups remained slightly depressed. 4. Energy restriction of about 8% during the second period depressed rate of lay by about 3% points and egg weight by about 2%.