Mixed Spices at Culinary Doses Have Prebiotic Effects in Healthy Adults: A Pilot Study.
Plain language summary
An increasing body of evidence suggests that the gut microbiota has a profound impact on human health. While the microbiome of a healthy individual is relatively stable, gut microbial dynamics can be influenced by host lifestyle and dietary choices. The aim of this study was to investigate the effects of mixed spices (cinnamon, oregano, ginger, black pepper, and cayenne pepper) at culinary doses consumed over 2 weeks in a standardized 5g capsule on the production of gut microbiota and short-chain fatty acids The study is a randomised, placebo-controlled, double-blind pilot study carried out with a total of 31 healthy women and men aged between 18 and 65. The subjects were randomly allocated to one of the two intervention groups. Results indicate that daily intake of 5g of mixed spices for 2 weeks in healthy subjects resulted in a significant reduction in the relative abundance of the phylum Firmicutes (bacteria), and a trend of increasing in phylum Bacteroidetes (bacteria) as compared with a matched control group. Authors conclude that a mixture of spices at culinary doses affects the composition of gut microbiota.
undefined: Spices were used as food preservatives prior to the advent of refrigeration, suggesting the possibility of effects on microbiota. Previous studies have shown prebiotic activities in animals and in vitro, but there has not been a demonstration of prebiotic or postbiotic effects at culinary doses in humans. In this randomized placebo-controlled study, we determined in twenty-nine healthy adults the effects on the gut microbiota of the consumption daily of capsules containing 5 g of mixed spices at culinary doses by comparison to a matched control group consuming a maltodextrin placebo capsule. The 16S ribosomal RNA sequencing data were used for microbial characterization. Spice consumption resulted in a significant reduction in Firmicutes abundance ( < 0.033) and a trend of enrichment in Bacteroidetes ( < 0.097) compared to placebo group. Twenty-six operational taxonomic units (OTUs) were different between the spice and placebo groups after intervention. Furthermore, there was a significant negative correlation between fecal short-chain fatty acid propionate concentration and Firmicutes abundance in spice intervention group ( < 0.04). The production of individual fecal short-chain fatty acid was not significantly changed by spice consumption in this study. Mixed spices consumption significantly modified gut microbiota, suggesting a prebiotic effect of spice consumption at culinary doses.
Protein-enriched meal replacements do not adversely affect liver, kidney or bone density: an outpatient randomized controlled trial.
Nutrition journal. 2010;:72
BACKGROUND There is concern that recommending protein-enriched meal replacements as part of a weight management program could lead to changes in biomarkers of liver or renal function and reductions in bone density. This study was designed as a placebo-controlled clinical trial utilizing two isocaloric meal plans utilizing either a high protein-enriched (HP) or a standard protein (SP) meal replacement in an outpatient weight loss program. SUBJECTS/METHODS 100 obese men and women over 30 years of age with a body mass index (BMI) between 27 to 40 kg/m2 were randomized to one of two isocaloric weight loss meal plans 1). HP group: providing 2.2 g protein/kg of lean body mass (LBM)/day or 2). SP group: providing 1.1 g protein/kg LBM/day. Meal replacement (MR) was used twice daily (one meal, one snack) for 3 months and then once a day for 9 months. Body weight, lipid profiles, liver function, renal function and bone density were measured at baseline and 12 months. RESULTS Seventy subjects completed the study. Both groups lost weight (HP -4.29 ± 5.90 kg vs. SP -4.66 ± 6.91 kg, p < 0.01) and there was no difference in weight loss observed between the groups at one year. There was no significant change noted in liver function [AST (HP -2.07 ± 10.32 U/L, p = 0.28; SP 0.27 ± 6.67 U/L, p = 0.820), ALT (HP -1.03 ± 10.08 U/L, p = 0.34; SP -2.6 ± 12.51 U/L, p = 0.24), bilirubin (HP 0.007 ± 0.33, U/L, p = 0.91; SP 0.07 ± 0.24 U/L, p = 0.120), alkaline phosphatase (HP 2.00 ± 9.07 U/L, p = 0.240; SP -2.12 ± 11.01 U/L, p = 0.280)], renal function [serum creatinine (HP 0.31 ± 1.89 mg/dL, p = 0.380; SP -0.05 ± 0.15 mg/dL, p = 0.060), urea nitrogen (HP 1.33 ± 4.68 mg/dL, p = 0.130; SP -0.24 ± 3.03 mg/dL, p = 0.650), 24 hour urine creatinine clearance (HP -0.02 ± 0.16 mL/min, p = 0.480; SP 1.18 ± 7.53 mL/min, p = 0.400), and calcium excretion (HP -0.41 ± 9.48 mg/24 hours, p = 0.830; SP -0.007 ± 6.76 mg/24 hours, p = 0.990)] or in bone mineral density by DEXA (HP 0.04 ± 0.19 g/cm2, p = 0.210; SP -0.03 ± 0.17 g/cm2, p = 0.320) in either group over one year. CONCLUSIONS These studies demonstrate that protein-enriched meals replacements as compared to standard meal replacements recommended for weight management do not have adverse effects on routine measures of liver function, renal function or bone density at one year.
Pistachio nuts reduce triglycerides and body weight by comparison to refined carbohydrate snack in obese subjects on a 12-week weight loss program.
Journal of the American College of Nutrition. 2010;(3):198-203
OBJECTIVE There is a widely held view that, due to high fat content, snacking on nuts will lead to weight gain, ultimately causing unhealthy changes in lipid profiles. This study is designed to study the effects of pistachio snack consumption on body weight and lipid levels in obese participants under real-world conditions. METHODS Participants were randomly assigned to consume 1 of 2 isocaloric weight reduction diets for 12 weeks, with each providing 500 cal per day less than resting metabolic rate. Each diet included an afternoon snack of either 53 g (240 cal) of salted pistachios (n = 31) or 56 g of salted pretzels (220 cal; n = 28). RESULTS Both groups lost weight during the 12-week study (time trend, p < 0.001), but there were significant differences in the changes in body mass index between the pretzel and pistachio groups (pistachio, 30.1 ± 0.4 to 28.8 ± 0.4 vs. pretzel, 30.9 ± 0.4 to 30.3 ± 0.5). At 6 and 12 weeks, triglycerides were significantly lower in the pistachio group compared with the pretzel group (88.04 ± 9.80 mg/dL vs. 144.56 ± 18.86 mg/dL, p = 0.01 at 6 weeks and 88.10 ± 6.78 mg/dL vs. 132.15 ± 16.76 mg/dL, p = 0.02 at 12 weeks), and there was a time trend difference between the 2 groups over the 12 weeks (p < 0.01). There were no significant differences in total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, insulin, or glucose between the 2 groups. CONCLUSION Pistachios can be consumed as a portion-controlled snack for individuals restricting calories to lose weight without concern that pistachios will cause weight gain. By comparison to refined carbohydrate snacks such as pretzels, pistachios may have beneficial effects on triglycerides as well.
A controlled trial of protein enrichment of meal replacements for weight reduction with retention of lean body mass.
Nutrition journal. 2008;:23
BACKGROUND While high protein diets have been shown to improve satiety and retention of lean body mass (LBM), this study was designed to determine effects of a protein-enriched meal replacement (MR) on weight loss and LBM retention by comparison to an isocaloric carbohydrate-enriched MR within customized diet plans utilizing MR to achieve high protein or standard protein intakes. METHODS Single blind, placebo-controlled, randomized outpatient weight loss trial in 100 obese men and women comparing two isocaloric meal plans utilizing a standard MR to which was added supplementary protein or carbohydrate powder. MR was used twice daily (one meal, one snack). One additional meal was included in the meal plan designed to achieve individualized protein intakes of either 1) 2.2 g protein/kg of LBM per day [high protein diet (HP)] or 2) 1.1 g protein/kg LBM/day standard protein diet (SP). LBM was determined using bioelectrical impedance analysis (BIA). Body weight, body composition, and lipid profiles were measured at baseline and 12 weeks. RESULTS Eighty-five subjects completed the study. Both HP and SP MR were well tolerated, with no adverse effects. There were no differences in weight loss at 12 weeks (-4.19 +/- 0.5 kg for HP group and -3.72 +/- 0.7 kg for SP group, p > 0.1). Subjects in the HP group lost significantly more fat weight than the SP group (HP = -1.65 +/- 0.63 kg; SP = -0.64 +/- 0.79 kg, P = 0.05) as estimated by BIA. There were no significant differences in lipids nor fasting blood glucose between groups, but within the HP group a significant decrease in cholesterol and LDL cholesterol was noted at 12 weeks. This was not seen in the SP group. CONCLUSION Higher protein MR within a higher protein diet resulted in similar overall weight loss as the standard protein MR plan over 12 weeks. However, there was significantly more fat loss in the HP group but no significant difference in lean body mass. In this trial, subject compliance with both the standard and protein-enriched MR strategy for weight loss may have obscured any effect of increased protein on weight loss demonstrated in prior weight loss studies using whole food diets.
Long-term efficacy of soy-based meal replacements vs an individualized diet plan in obese type II DM patients: relative effects on weight loss, metabolic parameters, and C-reactive protein.
European journal of clinical nutrition. 2005;(3):411-8
BACKGROUND Achieving significant weight loss and glycemic control in diabetic patients remains a challenging task. OBJECTIVE This study compared the effects of a soy-based meal replacement (MR) plan vs an individualized diet plan (IDP; as recommended by the American Diabetes Association) on weight loss and metabolic profile. DESIGN/SUBJECTS A total of 104 subjects were randomized prospectively to the two treatments for a total of 12 months. RESULTS In all, 77 of the 104 subjects completed the study. Percentage weight loss in MR group (4.57+/-0.81%) was significantly greater (P<0.05) than in IDP group (2.25+/-0.72%). Fasting plasma glucose was significantly reduced in MR group (126.4+/-4.9 mg/dl) compared with IDP group (152.5+/-6.6 mg/dl, P<0.0001) at 6 months but not at 12 months. Controlling for baseline levels, hemoglobin Alc level improved by 0.49+/-0.22% for those receiving MR when compared to IDP group (P<0.05). A greater number of subjects in MR group reduced their use of sulfonylureas (P<0.0001) and metformin (P<0.05) as compared to IDP group. High-sensitivity C-reactive protein (hs-CRP) decreased -26.3% (P = 0.019) in MR group compared to -7.06% (P = 0.338) in IDP group at 6 months. Similar changes were observed at 12 months with MR groups, with hs-CRP decreasing by -25.0% (P = 0.019) compared to -18.7% (P = 0.179) in IDP group. CONCLUSION This study demonstrates that MR is a viable strategy for weight reduction in diabetic patients, resulting in beneficial changes in measures of glycemic control and reduction of medications.
Liquid meal replacements and glycemic control in obese type 2 diabetes patients.
Obesity research. 2001;:341S-347S
OBJECTIVE Although weight management is an important component in the treatment of type 2 diabetes, there has been concern about the use of liquid meal replacements (MRs) in treating obese patients with type 2 diabetes because of the sugar content of the MRs. The goal of this study was to evaluate the safety and feasibility of using MRs for weight loss in obese patients with type 2 diabetes. RESEARCH METHODS AND PROCEDURES Seventy-five subjects with type 2 diabetes, treated only with oral agents, were recruited for this 12-week clinical study. Subjects were randomized into three groups using either a MR containing lactose, fructose, and sucrose, a MR in which fructose and sucrose were replaced with oligosaccharides (sugar-free Slim-Fast), or an exchange diet plan (EDP) using the proportion of macronutrients recommended by the American Diabetes Association. RESULTS Fifty-seven patients (41 MR and 16 EDP) finished the study. None developed serious adverse effects, including major hypoglycemic reactions. Weight losses in the MR 1 and MR 2 groups were comparable (6.4% and 6.7%, respectively) and greater than the weight loss in the EDP group (4.9%). Fasting glucose level was significantly reduced in the MR group compared with the EDP group (p = 0.012). There was a significant reduction in the MR group in total cholesterol and low-density lipoprotein cholesterol that was not seen in the EDP group. DISCUSSION We have shown that liquid MRs are a safe and effective weight loss tool for obese subjects with type 2 diabetes, and can result in improvements in body weight, glucose, insulin, hemoglobin A1c and lipid levels.