Commercial weight-loss diets, greenhouse gas emissions and freshwater consumption.

BACKGROUND: Weight-loss attempts are widespread in the United States, with many using commercial weight-loss diet plans for guidance and support. Accordingly, dietary suggestions within these plans influence the nation's food-related environmental footprint. METHODS: We modelled United States (US) per capita greenhouse gas emissions (GHGe) and water footprints associated with seven commercial weight-loss diets, the US baseline, and selected other dietary patterns. We characterised consumption in commercial weight-loss diets both via modelling from provided guidelines and based on specific foods in 1-week meal plans. Cradle-to-farmgate GHGe and water footprints were assessed using a previously developed model. GHGe results were compared to the EAT-Lancet 2050 target. Water footprints were compared to the US baseline. RESULTS: Weight-loss diets had GHGe footprints on average 4.4 times the EAT-Lancet target recommended for planetary health (range: 2.4-8.5 times). Bovine meat was by far the largest contributor of GHGe in most diets that included it. Three commercial diets had water footprints above the US baseline. Low caloric intake in some diets compensated for the relative increases in GHGe- and water-intensive foods. CONCLUSIONS: Dietary patterns suggested by marketing materials and guidelines from commercial weight-loss diets can have high GHGe and water footprints, particularly if caloric limits are exceeded. Commercial diet plan guidance can be altered to support planetary and individual health, including describing what dietary patterns can jointly support environmental sustainability and weight loss.

Developing and Piloting a Novel Ranking System to Assess Popular Dietary Patterns and Healthy Eating Principles.

A multitude of weight loss diets exist. However, no one diet has been proven to be superior, despite their claims. Resultingly, this creates confusion amongst consumers and conflicting nutrition messages. The aim of the ranking system was to evaluate a range of dietary pattern's nutrition profile and financial costs, as well as their potential long-term sustainability and associated adverse effects. Nutrition profile is typically the focal point of weight loss diets with less attention focused towards other factors that may affect their suitability. Five popular diets (Keto, Paleo, Intermittent Fasting, Optifast, and 8 Weeks to Wow) and two energy restricted healthy eating principles (Australian Guide to Healthy Eating and the Mediterranean Diet) were compared for diet quality, cost, adverse effects, and support for behaviour change. In general, healthy eating principles scored more favourably compared to popular weight loss diets in all categories. Lower carbohydrate diets tended to score lower for diet quality due to restricting multiple food groups, had more associated adverse effects and did not encourage behaviour change compared to the other weight loss diets. Optifast was the only weight loss diet to receive a negative score for cost. There should be considerations when undertaking a change to dietary patterns beyond nutrition profile. Diets indeed vary in terms of diet quality, and in addition can be costly, incur adverse effects, and disregard behaviour change which is important for sustainable weight loss and maintenance. This ranking system could create a reference point for future comparisons of diets.

Effects of gut microbiota and fatty acid metabolism on dyslipidemia following weight-loss diets in women: Results from a randomized controlled trial.

BACKGROUND & AIMS: In our early feeding trial among overweight and obese Chinese women, both low-carbohydrate (LC) and calorie-restricted (CR) diets reduced weight and fat mass, but only the LC diet significantly improved dyslipidemia. We aimed to investigate the impacts of altered gut microbiota, fatty acid (FAs), and acylcarnitines, markers of mitochondrial function on blood lipids. METHODS: Fecal and blood samples from 48 participants at baseline and the end of a 12-week trial were used to perform metagenomics and targeted-metabolomics including erythrocyte FAs and plasma acylcarnitines, respectively. RESULTS: The two diets altered microbial structure and co-abundance gene clusters (CAGs) at different magnitudes. After a 12-week intervention, the Bacteroidetes/Firmicutes ratio increased significantly in the LC diet (P = 0.015) but not in the CR diet, which only showed an increased trend (P = 0.28). At the microbial function level, the LC group showed lower branched-chain amino acid biosynthesis and higher serine biosynthesis than the CR group. Moreover, the LC diet reduced levels of 14:0 and 16:1n-7 FAs in the de novo lipogenesis pathway, but increased 20:5n-3 compared with the CR diet. Both groups had increased plasma acylcarnitines except that the LC group had larger elevated short-chain acylcarnitines. After backward stepwise selection, a cluster of changed CAGs, FAs and acylcarnitines were found to be associated with improved lipid profile. However, changed CAGs showed higher contribution rates in elevating HDL-cholesterol (81.6%) and reducing triglycerides (89.3%) than changed FAs and acylcarnitines. CONCLUSIONS: The two weight-loss diets induced different changes of gut microbiota, plasma acylcarnitines, and erythrocyte FAs. Changes in gut microbiota rather than FA or acylcarnitine profiles showed greater contribution to improved lipid profile in these overweight and obese Chinese women. TRIAL REGISTRATION: The trial was registered at http://clinicaltrials.gov/show/NCT01358890.

Psychopathological Risk Factors Associated with Body Image, Body Dissatisfaction and Weight-Loss Dieting in School-Age Adolescents.

Determining the comorbidity patterns leading to suffering behavioural eating disorders (BED) that are identifiable in the early stages of life, can help prevent their becoming chronic, as well as preventing the consequences deriving from the cost and effectiveness of intervention programs. The paper focuses mainly on analysing the association between behavioural/emotional risk factors and body image, body satisfaction and diet in school children, as well as confirming whether there are differences based on sex. Several questionnaires (Strengths and Difficulties Questionnaire and several items of Health Behaviour in School-age Children) including these variables were distributed and completed by the 647 adolescents (16 year olds on average) who took part in the research project. The findings confirmed a differentiated risk profile in adolescent girls in that they had greater prevalence of emotional symptoms as a general psychopathological trait, although this was offset with their prosocial behaviour. Additionally, the findings also allowed us to conclude that the factors that predict vulnerability to BEDs are sex, the presence of emotional symptoms and social and behavioural issues. At the end of this paper, we discuss some implications and consequences that should be taken into account for future work.

Defining the Optimal Dietary Approach for Safe, Effective and Sustainable Weight Loss in Overweight and Obese Adults.

Various dietary approaches with different caloric content and macronutrient composition have been recommended to treat obesity in adults. Although their safety and efficacy profile has been assessed in numerous randomized clinical trials, reviews and meta-analyses, the characteristics of the optimal dietary weight loss strategy remain controversial. This mini-review will provide general principles and practical recommendations for the dietary management of obesity and will further explore the components of the optimal dietary intervention. To this end, various dietary plans are critically discussed, including low-fat diets, low-carbohydrate diets, high-protein diets, very low-calorie diets with meal replacements, Mediterranean diet, and diets with intermittent energy restriction. As a general principle, the optimal diet to treat obesity should be safe, efficacious, healthy and nutritionally adequate, culturally acceptable and economically affordable, and should ensure long-term compliance and maintenance of weight loss. Setting realistic goals for weight loss and pursuing a balanced dietary plan tailored to individual needs, preferences, and medical conditions, are the key principles to facilitate weight loss in obese patients and most importantly reduce their overall cardiometabolic risk and other obesity-related comorbidities.

Micronutrient Gaps in Three Commercial Weight-Loss Diet Plans.

Weight-loss diets restrict intakes of energy and macronutrients but overlook micronutrient profiles. Commercial diet plans may provide insufficient micronutrients. We analyzed nutrient profiles of three plans and compared their micronutrient sufficiency to Dietary Reference Intakes (DRIs) for male U.S. adults. Hypocaloric vegan (Eat to Live-Vegan, Aggressive Weight Loss; ETL-VAWL), high-animal-protein low-carbohydrate (Fast Metabolism Diet; FMD) and weight maintenance (Eat, Drink and Be Healthy; EDH) diets were evaluated. Seven single-day menus were sampled per diet (n = 21 menus, 7 menus/diet) and analyzed for 20 micronutrients with the online nutrient tracker CRON-O-Meter. Without adjustment for energy intake, the ETL-VAWL diet failed to provide 90% of recommended amounts for B12, B3, D, E, calcium, selenium and zinc. The FMD diet was low (<90% DRI) in B1, D, E, calcium, magnesium and potassium. The EDH diet met >90% DRIs for all but vitamin D, calcium and potassium. Several micronutrients remained inadequate after adjustment to 2000 kcal/day: vitamin B12 in ETL-VAWL, calcium in FMD and EDH and vitamin D in all diets. Consistent with previous work, micronutrient deficits are prevalent in weight-loss diet plans. Special attention to micronutrient rich foods is required to reduce risk of micronutrient deficiency in design of commercial diets.

Pros & cons of some popular extreme weight-loss diets.

Obesity has now become a huge public health issue not only in the developed world but also in developing countries. In view of the health hazards associated with obesity and more importantly for cosmetic reasons, many people, particularly the youth, have started resorting to 'extreme' weight-loss diets to achieve a rapid reduction in weight. These extreme diets are either very low in carbohydrate or very low in fat. Such extreme diets not only make the diet unbalanced but also have safety issues. Moreover, these are not sustainable in the long run. The weight that is lost is regained within a short period of time when people go off these extreme diets. This explains why the popularity of most extreme diets peaks as well as wanes rapidly. Instead of resorting to such extreme diets, correction of obesity is best achieved with balanced, healthy, nutritious diets which are low in calories, combined with adequate physical activity (exercise). Motivational counselling can also help people to initiate weight loss and sustain this weight loss over longer periods of time.

Genetic variation of habitual coffee consumption and glycemic changes in response to weight-loss diet intervention: the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial.

Background: Coffee consumption has been associated with glucose metabolism and risk of type 2 diabetes.Objective: We examined whether the genetic variation determining habitual coffee consumption affected glycemic changes in response to weight-loss dietary intervention.Design: A genetic risk score (GRS) was calculated based on 8 habitual coffee consumption-associated single nucleotide polymorphisms. We used general linear models to test changes in glycemic traits in groups randomly assigned to high- and low-fat diets according to tertiles of the GRS.Results: We observed significant interactions between the GRS and low compared with high dietary fat intake on 6-mo changes in fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) (P-interaction = 0.023 and 0.022, respectively), adjusting for age, sex, race, physical activity, smoking, alcohol, seasonal variation, and baseline values of the respective outcomes. Participants with a higher GRS of habitual coffee consumption showed a greater reduction in fasting insulin and a marginally greater decrease in HOMA-IR in the low-fat diet intervention group.Conclusions: Our data suggest that participants with genetically determined high coffee consumption may benefit more by eating a low-fat diet in improving fasting insulin and HOMA-IR in a short term. This trial was registered at clinicaltrials.gov as NCT00072995 and NCT03258203.

Genetic susceptibility to diabetes and long-term improvement of insulin resistance and ß cell function during weight loss: the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial.

BACKGROUND: Diet interventions have shown effectiveness in improving diabetes risk factors; however, little is known about whether the effects of diet intervention are different according to genetic susceptibility. OBJECTIVE: We examined interactions between weight-loss diets and the genetic risk score (GRS) for diabetes on 2-y changes in markers of insulin resistance and ß cell function in a randomized controlled trial. DESIGN: Data from the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial were analyzed. A GRS was calculated on the basis of 31 diabetes-associated variants in 744 overweight or obese nondiabetic adults (80% white Americans). We assessed the changes in insulin resistance and ß cell function over the 2-y intervention. RESULTS: Dietary protein significantly interacted with the diabetes GRS on fasting insulin, glycated hemoglobin (HbA1c), the homeostasis model assessment of ß cell function (HOMA-B), and the homeostasis model assessment of insulin resistance (HOMA-IR) at 2 y in white Americans (P-interaction = 0.02, 0.04, 0.01, and 0.05, respectively). The lower GRS was associated with a greater decrease in fasting insulin (P = 0.04), HbA1c (P = 0.0001), and HOMA-IR (P = 0.02), and a lesser increase in HOMA-B (P = 0.004) in participants consuming a low-protein diet. Participants with a higher GRS might have a greater reduction in fasting insulin when consuming a high-protein diet (P = 0.03). CONCLUSIONS: Our data suggest that individuals with a lower genetic risk of diabetes may benefit more from consuming a low-protein weight-loss diet in improving insulin resistance and ß cell function, whereas a high-protein diet may be more beneficial for white patients with a higher genetic risk. This trial was registered at clinicaltrials.gov as NCT00072995.

Sarcopenic obesity and complex interventions with nutrition and exercise in community-dwelling older persons--a narrative review.

One of the many threats to independent life is the age-related loss of muscle mass and muscle function commonly referred to as sarcopenia. Another important health risk in old age leading to functional decline is obesity. Obesity prevalence in older persons is increasing, and like sarcopenia, severe obesity has been consistently associated with several negative health outcomes, disabilities, falls, and mobility limitations. Both sarcopenia and obesity pose a health risk for older persons per se, but in combination, they synergistically increase the risk for negative health outcomes and an earlier onset of disability. This combination of sarcopenia and obesity is commonly referred to as sarcopenic obesity. The present narrative review reports the current knowledge on the effects of complex interventions containing nutrition and exercise interventions in community-dwelling older persons with sarcopenic obesity. To date, several complex interventions with different outcomes have been conducted and have shown promise in counteracting either sarcopenia or obesity, but only a few studies have addressed the complex syndrome of sarcopenic obesity. Strong evidence exists on exercise interventions in sarcopenia, especially on strength training, and for obese older persons, strength exercise in combination with a dietary weight loss intervention demonstrated positive effects on muscle function and body fat. The differences in study protocols and target populations make it impossible at the moment to extract data for a meta-analysis or give state-of-the-art recommendations based on reliable evidence. A conclusion that can be drawn from this narrative review is that more exercise programs containing strength and aerobic exercise in combination with dietary interventions including a supervised weight loss program and/or protein supplements should be conducted in order to investigate possible positive effects on sarcopenic obesity.

Análise da composição nutricional de dietas da moda divulgadas por revistas não científicas / Analysis of the nutritional composition of fad diets in nonscientific magazines

Objetivo: Analisar a composi��o nutricional das dietas da moda divulgadas por revistas n�o cient�ficas. M�todos: Foi realizado estudo transversal descritivo de dietas da moda selecionadas em revistas n�o cient�ficas. A composi��o nutricional das dietas foi calculada pelo software AVANUTRI� e comparada com a recomenda��o proposta pelas DRIS (Dietary Reference Intakes) para macronutrientes e fibras alimentares de acordo com valores propostos pela IV Diretriz Brasileira sobre Dislipidemias e Preven��o da Aterosclerose. Para o c�lculo das dietas, foram adotadas como padr�o as recomenda��es para mulheres com 160cm e 61,8kg. Resultados: Foram analisadas 12 dietas publicadas em quatro revistas distintas. O aporte energ�tico oscilou de 720 a 1720kcal/dia. Ao comparar com os macronutrientes, 5 (41,6%) card�pios apresentaram quantidade excessiva de prote�nas; 6 (50%), insufici�ncia de carboidratos; 9 (45%), insufici�ncia de lip�deos; e apenas 2 (10%), quantidade suficiente de fibras. Conclus�o: Os resultados apontam que a maioria das dietas publicadas em revistas n�o cient�ficas apresenta inadequa��es na distribui��o de macronutrientes, o que pode comprometer o estado nutricional dos indiv�duos. Esses dados refor�am a import�ncia de que as dietas sejam individualizadas e acompanhadas por profissional habilitado, um nutricionista.

Objective: To evaluate the nutritional composition of fad diets in non-scientific magazines. Methods: This is a descriptive cross-sectional study of fad diets selected from non-scientific magazines. The nutritional composition of diets was calculated by AVANUTRI� software and compared with DRIS (Dietary Reference Intakes) for macronutrients and fibers according to the values proposed by the IV Brazilian Guidelines on Dyslipidemia and Prevention of Atherosclerosis. Standard recommendations for women of 160cm in height and 61.8kg in weight were adopted to perform the calculation of diets. Results: We analyzed 12 diets published in four different magazines. The energy intake ranged from 720 to 1720kcal/day. Regarding macronutrients, 05 (41.6%) menus presented excessive amount of protein, 06 (50%) showed carbohydrate insufficiency, 09 (45%) presented lipid insufficiency, and only 02 (10%) showed sufficient amount of fibers. Conclusion: The results indicate that most diets published in non-scientific magazines present inadequacies of nutrients, which may compromise the nutritional status of individuals. It is indispensable that diets be individualized and monitored by professional nutritionists.

Management of obesity in cats.

Obesity is a common nutritional disorder in cats, especially when they are neutered and middle-aged. Obesity predisposes cats to several metabolic and clinical disorders, including insulin resistance, diabetes mellitus, lameness, and skin disease. Prevention and treatment of obesity is therefore of great importance in veterinary practice. Correct assessment of body composition is important for recognizing early states of obesity and for monitoring success of weight-loss programs. Various methods for assessing body composition have been proposed, of which a 9-point body-condition score has been validated in cats, and is possibly the most simple to use in the clinic; however, for extremely obese individuals, it is less useful. When calculating the appropriate daily caloric intake for a weight-loss plan, the aim is to maintain a safe weight-loss rate, increasing the chance of preserving lean body mass and decreasing the risk of developing hepatic lipidosis, while also producing a sufficient weight-loss rate to keep owners motivated. A weight-loss rate of 0.5%-2% per week is recommended, which for a cat that needs to lose 3 kg body weight results in an anticipated time for reaching the target weight of 24-60 weeks. There are several purpose-made weight-loss diets available. The optimal composition of a weight-loss diet for cats is unknown, but most of the available products have lower caloric density, an increased nutrient:energy ratio, and higher protein and fiber content. Regular follow-up visits allow the caloric intake to be adjusted based on progress, and possibly increase the chance of success. This review discusses the risk factors for and consequences of obesity, and gives directions for formulating a weight-loss plan, including daily caloric intake, choice of diet, and common problems based on the current literature. This review further provides a nutritional comparison of the current composition of selected commercial veterinary-specific weight-loss diets.

Tailoring dietary approaches for weight loss.

Although the 'Low-Fat' diet was the predominant public health recommendation for weight loss and weight control for the past several decades, the obesity epidemic continued to grow during this time period. An alternative 'low-carbohydrate' (Low-Carb) approach, although originally dismissed and even vilified, was comparatively tested in a series of studies over the past decade, and has been found in general to be as effective, if not more, as the Low-Fat approach for weight loss and for several related metabolic health measures. From a glass half full perspective, this suggests that there is more than one choice for a dietary approach to lose weight, and that Low-Fat and Low-Carb diets may be equally effective. From a glass half empty perspective, the average amount of weight lost on either of these two dietary approaches under the conditions studied, particularly when followed beyond 1 year, has been modest at best and negligible at worst, suggesting that the two approaches may be equally ineffective. One could resign themselves at this point to focusing on calories and energy intake restriction, regardless of macronutrient distributions. However, before throwing out the half-glass of water, it is worthwhile to consider that focusing on average results may mask important subgroup successes and failures. In all weight-loss studies, without exception, the range of individual differences in weight change within any particular diet groups is orders of magnitude greater than the average group differences between diet groups. Several studies have now reported that adults with greater insulin resistance are more successful with weight loss on a lower-carbohydrate diet compared with a lower-fat diet, whereas adults with greater insulin sensitivity are equally or more successful with weight loss on a lower-fat diet compared with a lower-carbohydrate diet. Other preliminary findings suggest that there may be some promise with matching individuals with certain genotypes to one type of diet over another for increasing weight-loss success. Future research to address the macronutrient intake component of the obesity epidemic should build on these recent insights and be directed toward effectively classifying individuals who can be differentially matched to alternate types of weight-loss diets that maximize weight-loss and weight-control success.