Protein sparing therapies in acute illness and obesity: a review of George Blackburn's contributions to nutrition science

The Effectiveness of the Low-Glycemic and Insulinemic (LOGI) Regimen in Maintaining the Benefits of the VLCKD in Fibromyalgia Patients

Background: Fibromyalgia (FM) is a chronic disorder that causes damage to the neuro-muscular system and alterations in the intestinal microbiota and affects the psychological state of the patient. In our previous study, we showed that 22 women patients subjected to a specific very low-carbohydrate ketogenic therapy (VLCKD) showed an improvement in clinical scores as well as neurotransmission-related and psychological dysfunctions and intestinal dysbiosis. Furthermore, NMR metabolomic data showed that changes induced by VLCKD treatment were evident in all metabolic pathways related to fibromyalgia biomarkers. Methods: Based on this evidence, we extend our investigation into dietary interventions for fibromyalgia by evaluating the impact of transitioning from a VLCKD to a low-glycemic insulinemic (LOGI) diet over an additional 45-day period. Therefore, participants initially following a VLCKD were transitioned to the LOGI diet after 45 days to determine whether the improvements in FM symptoms and metabolic dysfunctions achieved through VLCKD could be sustained with LOGI. Results: Our findings suggested that while VLCKD serves as an effective initial intervention for correcting metabolic imbalances and alleviating FM symptoms, transitioning to a LOGI diet offers a practical and sustainable dietary strategy. This transition preserves clinical improvements and supports long-term adherence and quality of life, underscoring the importance of adaptable nutritional therapies in chronic disease management. Control patients who adhered only to the LOGI diet for 90 days showed only modest improvement in clinical and psychological conditions, but not elimination of fibromyalgia symptoms. Conclusions: In conclusion the LOGI diet is an excellent alternative to maintain the results obtained from the regime VLCKD.

Epigenome Modulation Induced by Ketogenic Diets

Ketogenic diets (KD) are dietary strategies low in carbohydrates, normal in protein, and high, normal, or reduced in fat with or without (Very Low-Calories Ketogenic Diet, VLCKD) a reduced caloric intake. KDs have been shown to be useful in the treatment of obesity, metabolic diseases and related disorders, neurological diseases, and various pathological conditions such as cancer, nonalcoholic liver disease, and chronic pain. Several studies have investigated the intracellular metabolic pathways that contribute to the beneficial effects of these diets. Although epigenetic changes are among the most important determinants of an organism’s ability to adapt to environmental changes, data on the epigenetic changes associated with these dietary pathways are still limited. This review provides an overview of the major epigenetic changes associated with KDs.

Effects of oral non-protein calorie supplements on nutritional status among maintenance hemodialysis patients with protein-energy wasting: a multi-center randomized controlled trial

Protein-energy wasting (PEW) is prevalent in maintenance hemodialysis (MHD) patients, and is one of the major risk factors for poor outcomes and death. This study aimed to investigate the effects of non-protein calorie supplements on the nutritional status of MHD patients with PEW. MHD patients with PEW were enrolled in this multi-center, open-label, randomized controlled trial. Then, they were randomly assigned to the intervention group to receive the non-protein calorie supplements containing 280 kcal of energy every day for 6 months or the control group to complete all aspects of the study without receiving supplements. Patients in both groups received dietary counselling from dietitians. Data on nutritional assessments, anthropometric measurements, blood analysis and dietary recall were collected at the baseline and at six months from both groups. Statistical analyses were performed using analysis of covariance (ANCOVA) adjusted for sex and baseline values. Ninety-two MHD patients completed the study. A significant increase in the subjective global assessment (SGA) score was found in the intervention group compared with the control group (4.88 ± 1.41 vs. 4.40 ± 1.16, p = 0.044). The ratio of PEW patients (diagnosed with SGA ≤5) in the intervention group (61.2%) was also significantly lower than that in the control group (83.7%) (p < 0.001). Moreover, significant improvements in body mass index (20.81 ± 2.46 kg m^-2vs. 19.51 ± 2.60 kg m^-2, p < 0.001), nutrition risk screening 2002 (2.45 ± 1.40 vs. 3.12 ± 1.37, p = 0.038), mid-upper arm circumference (23.30 ± 2.78 cm vs. 21.75 ± 2.87 cm, p = 0.001), and mid-arm muscle circumference (20.51 ± 2.32 cm vs. 19.06 ± 2.92 cm, p = 0.005) were observed in the intervention group compared with the control group. Patients in the intervention group took in more dietary energy than the control group (26.96 ± 4.75 kcal per kg body weight per day vs. 24.33 ± 2.68 kcal per kg body weight per day, p < 0.001). In conclusion, non-protein calorie supplements may improve the nutritional status of MHD patients with PEW.

Intermittent fasting for obesity and related disorders: unveiling myths, facts, and presumptions

Intermittent fasting (IF) is an increasingly popular method of weight loss, as an alternative to daily caloric restriction (DCR). Several forms of IF exist, such as alternate-day fasting or time-restricted feeding regimens. Some of its proponents claim several health benefits unrelated to caloric restriction or weight loss, which rely mainly on animal models. Although several studies published in the last few years confirm that IF can be a useful and safe therapeutical option for obesity and related disorders, no superiority to conventional caloric restriction diets have emerged. There are still several questions left answered. In this Review, we discuss some of the claims, unveiling myths, facts, and presumptions about several models of IF. The focus of this article is obesity, but there is a brief discussion of the potential benefits of IF on overall human health.

Ketogenic diets as treatment of obesity and type 2 diabetes mellitus

During the last decades, several interventions for the management of overweight and obesity have been proposed. Among diets, the first studies focused on the effect of water only and total fasting diets with or without proteins. Unfortunately, they were found to be associated with adverse events which lead to the abandon of these strategies. Interestingly, despite the radical approach, total fasting was effective and generally well tolerated. A strict connection between protein-calorie malnutrition and increased in morbidity and mortality in hospitalized patients was found at that time. Then, the seminal works of Blackburn and his collaborators lead to the introduction of the protein-sparing modified fast. Encouraged by the early results using this intervention, diets evolved to the current very-low-calorie ketogenic diets (VLCKD). In the present review, results of studies on the VLCKDs are presented and discussed, with a particular reference to the protocolled VLCKD. Also, a recent proposal on the nomenclature on the ketogenic diets is reported. Available evidence suggests VLCKDs to be effective in achieving a rapid and significant weight loss by means of an easily reversible intervention which could be repeated, if needed. Muscle mass and strength are preserved, resting metabolic rate is not impaired, hunger, appetite and mood are not worsened. Symptoms and abnormal laboratory findings can be there, but they have generally been reported as of mild intensity and transient. Preliminary studies suggest VLCKDs to be a potential game-changer in the management of type 2 diabetes too. Therefore, VLCKDs should be considered as an excellent initial step in properly selected and motivated patients with obesity or type 2 diabetes, to be delivered as a part of a multicomponent strategy and under strict medical supervision.

Confusion in the nomenclature of ketogenic diets blurs evidence

Ketogenic diets have been proposed as a non-pharmacological strategy for the management of several chronic conditions. Their efficacy and safety have been evaluated in the field of neurology, oncology and endocrinology for disorders including cancer, dementia, drug-resistant epilepsy, migraines, obesity, polycystic ovary syndrome and type 2 diabetes mellitus. The nutritional requirements of these subjects are expected to differ significantly. Indeed, although all ketogenic diets restrict carbohydrates, each intervention is characterized by a specific daily calorie intake, macronutrient composition and duration. However, the adopted nomenclature was often unclear to the general reader; also, the same abbreviations for different protocols were used. This possibly resulted in mistakes in the interpretation of the available evidence and limited the impact of studies on the topic in the clinical practice. Adopting a clear and consistent vocabulary is key in any context. Here, we present a practical and clinically-based proposal for the classification and abbreviation of ketogenic diets.

The Effect of Starting the Protein-Sparing Modified Fast on Weight Change over 5 years

BACKGROUND

Ketogenic diets have been highlighted as a way to lose weight while experiencing reduced hunger. The protein-sparing modified fast (PSMF) induces ketosis but may be difficult to maintain.

OBJECTIVE

To track weight loss for individuals initiating PSMF versus all other diets (e.g., balanced, high protein) for up to 5 years.

DESIGN

Retrospective cohort study PARTICIPANTS: Adults who discussed the PSMF with a clinician between 2007 and 2014 INTERVENTION: Initiating the PSMF diet versus other diets MEASURES: The main outcome was percent weight change up to 5 years. Demographic and health data were collected using electronic health records. We fit regression models including age, sex, race, insurance, new medication prescriptions, and specialist visit to identify the effect of PSMF diet on percent weight change. We grouped patients by percent weight change at each year (≥ 5% loss, 4% loss to 4% gain, ≥ 5% gain) and used Pearson χ² tests to compare proportions.

RESULTS

Of 1,403 eligible patients, 879 (63%) started the PSMF. The PSMF group was slightly younger (52 vs. 54 years, p < 0.01) and had a higher body mass index (41.9 kg/m² vs. 40.4 kg/m², p < 0.001). In the adjusted analysis, the PSMF group averaged 3% more weight loss than the other group over the 5-year follow-up (95% CI - 3.5, - 2.0, p < 0.001). PSMF patients lost more weight initially, but by year 4, there was no difference between diets (1.6% versus 1.3%, PSMF versus other diets, p = 0.12). Patients starting the PSMF were more likely to experience ≥ 5% weight loss at 1 year (55% vs 20%, p < 0.001) and 3 years (33% vs. 23% p < 0.05), but not 5 years (34% vs 29%, p = 0.16, PSMF versus other diets, respectively).

CONCLUSIONS

In clinical practice, the PSMF achieves rapid weight loss in the first 6 months, but only a small percentage of patients maintained significant weight loss long term.

A word of caution against excessive protein intake

Dietary protein is crucial for human health because it provides essential amino acids for protein synthesis. In addition, dietary protein is more satiating than carbohydrate and fat. Accordingly, many people consider the protein content when purchasing food and beverages and report 'trying to eat more protein'. The global market for protein ingredients is projected to reach approximately US$90 billion by 2021, largely driven by the growing demand for protein-fortified food products. This Perspective serves as a caution against the trend of protein-enriched diets and provides an evidence-based counterpoint that underscores the potential adverse public health consequences of high protein intake.

Using a Revised Protein-Sparing Modified Fast (rPSMF) for Children and Adolescents with Severe Obesity: A Pilot Study

Treatment options are limited for children and adolescents with severe obesity. One alternative treatment is the protein-sparing modified fast (PSMF), a low-carbohydrate, high-protein diet that can result in substantial weight loss. The aim of the study is to evaluate the adherence and efficacy of a revised PSMF (rPSMF) for severe obesity in a pediatric tertiary care weight-management program. The rPSMF with 1200-1800 calories, 40-60 g of carbohydrate/day and 1.2-1.5 g protein/kg of ideal bodyweight was implemented over 12 months. Twenty-one participants enrolled in the study. Mean age 16.2 ± 1.4 years, females (76.2%) and mean weight at baseline was 119 ± 19.9 kg. Regardless of adherence to the rPSMF, the mean weight change at 1 month was -3.7 ± 3.5 kg, (range -13.5 kg to 0.9 kg); at 3 months was -5.5 ± 5.1 kg, (range -19.3 kg to 1.8 kg) and at 6 months was -4.7 ± 6.6 kg, (range -18.3 kg to 8.6 kg). At 12 months, the mean weight change was -1.3 ± 10.6 kg (range -17.7 kg to 14.8 kg). Parent and child-reported physical and psychosocial quality of life (HRQOL) improved. Despite limited adherence, the rPSMF diet resulted in clinically significant weight loss and improved HRQOL for children and adolescents with severe obesity.

A Randomized Double-Blind, Cross-Over Trial of very Low-Calorie Diet in Overweight Migraine Patients: A Possible Role for Ketones?

Here we aimed at determining the therapeutic effect of a very low-calorie diet in overweight episodic migraine patients during a weight-loss intervention in which subjects alternated randomly between a very low-calorie ketogenic diet (VLCKD) and a very low-calorie non-ketogenic diet (VLCnKD) each for one month. In a nutritional program, 35 overweight obese migraine sufferers were allocated blindly to 1-month successive VLCKD or VLCnKD in random order (VLCKD-VLCnKD or VLCnKD-VLCD). The primary outcome measure was the reduction of migraine days each month compared to a 1-month pre-diet baseline. Secondary outcome measures were 50% responder rate for migraine days, reduction of monthly migraine attacks, abortive drug intake and body mass index (BMI) change. Only data from the intention-to-treat cohort (n = 35) will be presented. Patients who dropped out (n = 6) were considered as treatment failures. Regarding the primary outcome, during the VLCKD patients experienced -3.73 (95% CI: -5.31, -2.15) migraine days respect to VLCnKD (p < 0.0001). The 50% responder rate for migraine days was 74.28% (26/35 patients) during the VLCKD period, but only 8.57% (3/35 patients) during VLCnKD. Migraine attacks decreased by -3.02 (95% CI: -4.15, -1.88) during VLCKD respect to VLCnKD (p < 0.00001). There were no differences in the change of acute anti-migraine drug consumption (p = 0.112) and BMI (p = 0.354) between the 2 diets. A VLCKD has a preventive effect in overweight episodic migraine patients that appears within 1 month, suggesting that ketogenesis may be a useful therapeutic strategy for migraines.

High-Protein Hypocaloric Nutrition for Non-Obese Critically Ill Patients

High-protein hypocaloric nutrition, tailored to each patient's muscle mass, protein-catabolic severity, and exogenous energy tolerance, is the most plausible nutrition therapy in protein-catabolic critical illness. Sufficient protein provision could mitigate the rapid muscle atrophy characteristic of this disease while providing urgently needed amino acids to the central protein compartment and sites of tissue injury. The protein dose may range from 1.5 to 2.5 g protein (1.8-3.0 g free amino acids)/kg dry body weight per day. Nutrition should be low in energy (≈70% of energy expenditure or ≈15 kcal/kg dry body weight per day) because efforts to match energy provision to energy expenditure are physiologically irrational, risk toxic energy overfeeding, and have repeatedly failed in large clinical trials to demonstrate clinical benefit. The American Society for Parenteral and Enteral Nutrition currently suggests high-protein hypocaloric nutrition for obese critically ill patients. Short-term high-protein hypocaloric nutrition is physiologically and clinically sensible for most protein-catabolic critically ill patients, whether obese or not.