High protein diet promotes body weight loss among Brazilian postpartum women

Quality of low-carbohydrate diets among Australian post-partum women: Cross-sectional analysis of a national population-based cohort study

Low-carbohydrate diets (LCDs) are popular among people attempting weight loss and recommended for pregnant women with gestational diabetes (GDM), but they may increase health risks if nutritionally inadequate. We aimed to describe the dietary intake of post-partum women according to their relative carbohydrate intake, overall, and among women attempting weight loss or diagnosed with GDM in their recent pregnancy. This cross-sectional population-based cohort study included 2093 post-partum women aged 25-36 years who participated in the Australian Longitudinal Study on Women's Health. Dietary intake was assessed using a validated food frequency questionnaire. Relative carbohydrate intake was determined using a previously developed LCD score. Data were weighted to account for oversampling of women from rural/remote areas. More than half of women (n[weighted] = 1362, 66.3%) were trying to lose weight, and 4.6% (n[weighted]=88) had GDM in their recent pregnancy. Women with the lowest relative carbohydrate intake (LCD score quartile 4) consumed 36.8% of total energy intake from carbohydrates, and had a lower intake of refined grains, whole grains, fruit and fruit juice, and a higher intake of red and processed meat, compared with women with the highest relative carbohydrate intake (quartile 1). Different food groups, both healthy and unhealthy, were restricted depending on whether women were attempting weight loss and had recent GDM. These findings may reflect a lack of knowledge among post-partum women on carbohydrates and dietary guidelines. Health professionals may have an important role in providing advice and support for post-partum women who wish to restrict their carbohydrate intake, to ensure optimal diet quality.

Weight Reduction and Changes in Body Circumferences in Lactating Women as a Function of Differences in Dietary Macronutrient Content

Objectives: Investigating waist circumference (WC) and abdominal circumference (AC) evolution in lactating women, based on macronutrient intake adequacy up to 6 months after childbirth. Materials and Methods: Prospective cohort comprising lactating women recruited at a maternity hospital in Minas Gerais State, Brazil, from June 2018 to June 2019. Selected individuals were healthy adult women who had given birth 72 hours before data collection. Sociodemographic, breastfeeding, and anthropometric data were collected. Food intake was determined through 24 hours dietary recalls. Adequate carbohydrate, protein, and lipid intake was herein defined as 45-65%, 10-35%, and 20-35% of the caloric value consumed by participants, respectively. Wilcoxon test and generalized estimating equations were carried out. This research was approved by the Research Ethics Committee, as well as by the National Research Ethics Committee. Results: There was decrease in weight (-4.45 kg), body mass index (-4.43 kg/m²), WC (-4.70 cm), and AC (-4.70 cm) values from the baseline (n = 260) up to 6 months after childbirth (p < 0.001). The evolution of these measurements has indicated that high carbohydrate and low protein intake were associated with the highest AC values. Low protein and high lipid intake have led to lower WC values (p < 0.05). Conclusions: Macronutrient intake adequacy by the investigated lactating women has influenced their WC and AC evolution. This outcome has evidenced the important role played by nutritional monitoring in puerperium to prevent abdominal fat retention after pregnancy.

Metabolomics analysis of urine from rats given long-term high-protein diet using ultra-high-performance liquid chromatography-mass spectrometry

Previous studies have indicated high-protein diet (HPD) promotes weight loss and improves metabolic parameters, but most of these studies have focused on the impact of short-term, long-term effects remain unclear. In this study, male Wistar rats were fed two diets for 88 weeks: normal control diet (NCD, 20.5% of energy as protein) or HPD (30.5% of energy as protein). At 88 weeks intervention, compared to NCD rats, HPD rats had lower fat tissue and higher skeletal muscle to body weight ratio, but there were no significantly differences in body weight and food intake. To explore the mechanism underlying metabolism and diet, we further collected rat urine samples at 16, 40, 64 and 88 weeks diet treatment and analyzed metabolomics profiles using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). Partial least squares-discriminant analysis (PLS-DA) scores plots from ESI- or ESI+ model revealed a perfect separation between two diets at four time points. We identified 11 dramatically different metabolites (with VIP cut-off value > 1) in HPD, including 3 up-regulated and 8 down-regulated. And these 11 metabolites were identified as effective biomarkers, which were significantly related to HPD-induced metabolism related outcomes (fat tissue and skeletal muscle to body weight ratio). Our results provided vital information regarding metabolism in long-term HPD and more importantly, a few potentially promising metabolites were firstly identified which may related to metabolic responses.

PET/CT Imaging and Physiology of Mice on High Protein Diet

Background: High protein (HP) diets have been proposed to reduce body weight in humans. The diets are known to alter energy metabolism, which can affect the quality of [¹⁸F]FDG PET heart images. In this preclinical study, we therefore explore the impact of a prolonged HP diet on myocardial [¹⁸F]FDG uptake. Methods: C57BL/6J (Black six (Bl6)) and apolipoprotein E-deficient (apoE^−/−) mice were fed chow, a HP diet, or a low protein (LP) diet for 12 weeks. At baseline and after treatment, the animals were injected with 33.0 MBq of [¹⁸F]FDG and a 30 min PET/CT scan was made. Myocardial volume and [¹⁸F]FDG uptake were quantified using PET and the % of body fat was calculated from CT. Results: Myocardial [¹⁸F]FDG uptake was similar for all diets at the follow-up scan but an increase between baseline and follow-up scans was noticed in the LP groups. Myocardial volume was significantly smaller in the C57BL HP group compared to the other Bl6 groups. Body weight increased less in the two HP groups compared to the chow and LP groups. Body fat percentage was significantly higher in the LP groups. This effect was stronger in C57BL mice (28.7%) compared to apoE^−/− mice (15.1%). Conclusions: Myocardial uptake of [¹⁸F]FDG in mice is not affected by increased protein intake but [¹⁸F]FDG uptake increases when the amount of protein is lowered. A lower body weight and percentage of body fat were noticed when applying a HP diet.

High protein diet promotes body weight loss among Brazilian postpartum women

There is evidence in the general population that adhering to a high protein and low carbohydrate diet may help in losing weight. However, there is little evidence among postpartum women. The aim of this study is to evaluate the effect of a high protein diet on weight loss among postpartum women. A parallel-randomized controlled trial with 94 postpartum women was conducted in a maternity ward in Mesquita county (recruitment from February 2009 to December 2010) and in a polyclinic in Rio de Janeiro city (recruitment from December 2010 to December 2011). Women were randomized to the intervention group (IG) or control group (CG), and both groups received an isocaloric diet (1,800 kcal). Additionally, the IG received approximately 25 g of protein obtained from 125 g per week of sardine to increase daily dietary protein content and was advised to restrict carbohydrate intake. The CG received nutritional counselling to follow the national nutrition guidelines (15% protein, 60% carbohydrates, and 25% lipids). A linear mixed-effects model was used to test the effect of high protein intake and macronutrient intake on weight loss during the postpartum period. Body weight decreased in the IG compared with the CG (ß = -0.325; p = 0.049) among overweight and obese postpartum women. The percentage of energy intake from lipid (ß = -0.023; p = 0.050) was negatively associated with body weight, and carbohydrate intake (ß = 0.020; p = 0.026) was positively associated with body weight over time among all women. Protein intake and lower carbohydrate intake may be used as a dietary strategy to improve body weight loss during the postpartum period.