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Anti-Inflammatory Effects of a Vegan Diet Versus the American Heart Association-Recommended Diet in Coronary Artery Disease Trial.
Shah, B, Newman, JD, Woolf, K, Ganguzza, L, Guo, Y, Allen, N, Zhong, J, Fisher, EA, Slater, J
Journal of the American Heart Association. 2018;7(23):e011367
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Inflammation plays a central role in the progression of atherosclerosis and is associated with adverse cardiovascular events. The aim of this study was to determine the effects of a vegan versus American Heart Association (AHA)-recommended diet on high-sensitivity C-reactive protein (hsCRP) [a type of protein found in blood plasma], as well as other markers of inflammation, glucometabolic markers, and lipid profiles in patients with established coronary artery disease (CAD) on guideline-directed medical therapy. This study is a prospective, randomized, open-label, blinded end point study design. The active study duration was 8 weeks, with an interim visit at 4 weeks and a final visit at 8 weeks. Results show: - a significantly greater reduction in hsCRP with a vegan versus AHA-recommended diet in patients with established CAD on guideline-directed medical therapy. - that the degree of weight loss, as measured by both body mass index and waist circumference, did not significantly differ between the 2 diet groups. - that markers of glycaemic control and lipid profiles, overall, also did not significantly differ in the vegan diet group when compared with the AHA-recommended diet group. Authors conclude that in patients with CAD and an elevated hsCRP, despite guideline-directed medical therapy, a vegan diet may be considered to further lower the parameters of inflammation.
Abstract
Background Dietary interventions may play a role in secondary cardiovascular prevention. hsCRP (High-sensitivity C-reactive protein) is a marker of risk for major adverse cardiovascular outcomes in coronary artery disease. Methods and Results The open-label, blinded end-point, EVADE CAD (Effects of a Vegan Versus the American Heart Association-Recommended Diet in Coronary Artery Disease) trial randomized participants (n=100) with coronary artery disease to 8 weeks of a vegan or American Heart Association-recommended diet with provision of groceries, tools to measure dietary intake, and dietary counseling. The primary end point was high-sensitivity C-reactive protein. A linear regression model compared end points after 8 weeks of a vegan versus American Heart Association diet and adjusted for baseline concentration of the end point. Significance levels for the primary and secondary end points were set at 0.05 and 0.0015, respectively. A vegan diet resulted in a significant 32% lower high-sensitivity C-reactive protein (β, 0.68, 95% confidence interval [0.49-0.94]; P=0.02) when compared with the American Heart Association diet. Results were consistent after adjustment for age, race, baseline waist circumference, diabetes mellitus, and prior myocardial infarction (adjusted β, 0.67 [0.47-0.94], P=0.02). The degree of reduction in body mass index and waist circumference did not significantly differ between the 2 diet groups (adjusted β, 0.99 [0.97-1.00], P=0.10; and adjusted β, 1.00 [0.98-1.01], P=0.66, respectively). There were also no significant differences in markers of glycemic control between the 2 diet groups. There was a nonsignificant 13% reduction in low-density lipoprotein cholesterol with the vegan diet when compared with the American Heart Association diet (adjusted β, 0.87 [0.78-0.97], P=0.01). There were no significant differences in other lipid parameters. Conclusions In patients with coronary artery disease on guideline-directed medical therapy, a vegan diet may be considered to lower high-sensitivity C-reactive protein as a risk marker of adverse outcomes. Clinical Trial Registration URL http://www.clinicaltrials.gov . Unique identifier: NCT 02135939.
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Hypothesis and data-driven dietary patterns and colorectal Cancer survival: findings from Newfoundland and Labrador colorectal Cancer cohort.
Sharma, I, Roebothan, B, Zhu, Y, Woodrow, J, Parfrey, PS, Mclaughlin, JR, Wang, PP
Nutrition journal. 2018;17(1):55
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Diet and lifestyle play a role in the risk and outcome of chronic diseases including colorectal cancer (CRC). This prospective follow-up study looked at the association between different dietary patterns and the risk of death and cancer recurrence in people with CRC. Over 500 CRC patients diagnosed between 1999 and 2003 were followed-up until 2010. Participants completed a food frequency questionnaire based on their diet a year prior to diagnosis, and this was used to identify several dietary patterns. Diets that were high in processed meats (HR 1.82), meat and dairy products (HR 2.19), and total grains, sugar and soft drinks (HR 1.95) were associated with a higher risk of mortality, cancer recurrence or metastasis. Poor adherence to a Mediterranean-style diet increased the risk of overall mortality (HR 1.62). Prudent vegetable, high sugar pattern, Recommended Food Scores and Dietary Inflammatory Index had no significant association with either mortality or combined mortality, recurrence or metastasis. The authors concluded that the risk of mortality, recurrence and metastasis in patients with colorectal cancer varies with different dietary patterns.
Abstract
BACKGROUND Dietary patterns are commonly used in epidemiological research, yet there have been few studies assessing if and how research results may vary across dietary patterns. This study aimed to estimate the risk of mortality/recurrence/metastasis using different dietary patterns and comparison amongst the patterns. METHODS Dietary patterns were identified by Cluster Analysis (CA), Principal Component Analysis (PCA), Alternate Mediterranean Diet score (altMED), Recommended Food Score (RFS) and Dietary Inflammatory Index (DII) scores using a 169-item food frequency questionnaire. Five hundred thirty-two colorectal cancer patients diagnosed between 1999 and 2003 in Newfoundland were followed-up until 2010. Overall Mortality (OM) and combined Mortality, Recurrence or Metastasis (cMRM) were identified. Comparisons were made with adjusted Cox proportional Hazards Ratios (HRs), correlation coefficients and the distributions of individuals in defined clusters by quartiles of factor and index scores. RESULTS One hundred and seventy cases died from all causes and 29 had a cancer recurrence/metastasis during follow-up. Processed meats as classified by PCA (HR 1.82; 95% confidence interval (CI) 1.07-3.09), clusters characterized by meat and dairy products (HR 2.19; 95% CI 1.03-4.67) and total grains, sugar, soft drinks (HR 1.95; 95% CI 1.13-3.37) were associated with a higher risk of cMRM. Poor adherence to AltMED increased the risk of all-cause OM (HR 1.62; 95% CI 1.04-2.56). Prudent vegetable, high sugar pattern, RFS and DII had no significant association with both OM and cMRM. CONCLUSION Estimation of OM and cMRM varied across dietary patterns which is attributed to the differences in the foundation of each pattern.
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Effect of intermittent vs. daily calorie restriction on changes in weight and patient-reported outcomes in people with multiple sclerosis.
Fitzgerald, KC, Vizthum, D, Henry-Barron, B, Schweitzer, A, Cassard, SD, Kossoff, E, Hartman, AL, Kapogiannis, D, Sullivan, P, Baer, DJ, et al
Multiple sclerosis and related disorders. 2018;23:33-39
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Multiple sclerosis (MS) is a disease of the central nervous system. Dietary modification is emerging as a safe intervention to potentially modify disease course. The main aim of this study was to assess the safety and feasibility of an intermittent fasting diet in people with MS. Secondary outcomes explored the effects of calorie restriction (CR) diets on body weight and anthropometric characteristics as well as on patient-reported outcomes including fatigue, sleep and mood. The study is a pilot randomised controlled feeding study of three different types of diets. Each participant (n=36) was randomized to 1 of 3 diets: a control diet (placebo), a daily CR diet and intermittent CR diet. Results indicate that daily CR diet was associated with marginally greater weight loss than the intermittent CR diet. Both CR diets were associated with trends toward improvements in cardiometabolic outcomes. Furthermore, CR diets were associated with in improvements in emotional well-being. Authors conclude that CR and weight loss represent interventions for clinically relevant symptoms due to MS, such as emotional well-being, without adding meaningful risks or adverse outcomes.
Abstract
An intermittent fasting or calorie restriction diet has favorable effects in the mouse forms of multiple sclerosis (MS) and may provide additional anti-inflammatory and neuroprotective advantages beyond benefits obtained from weight loss alone. We conducted a pilot randomized controlled feeding study in 36 people with MS to assess safety and feasibility of different types of calorie restriction (CR) diets and assess their effects on weight and patient reported outcomes in people with MS. Patients were randomized to receive 1 of 3 diets for 8 weeks: daily CR diet (22% daily reduction in energy needs), intermittent CR diet (75% reduction in energy needs, 2 days/week; 0% reduction, 5 days/week), or a weight-stable diet (0% reduction in energy needs, 7 days/week). Of the 36 patients enrolled, 31 (86%) completed the trial; no significant adverse events occurred. Participants randomized to CR diets lost a median 3.4 kg (interquartile range [IQR]: -2.4, -4.0). Changes in weight did not differ significantly by type of CR diet, although participants randomized to daily CR tended to have greater weight loss (daily CR: -3.6 kg [IQR: -3.0, -4.1] vs. intermittent CR: -3.0 kg [IQR: -1.95, -4.1]; P = 0.15). Adherence to study diets differed significantly between intermittent CR vs. daily CR, with lesser adherence observed for intermittent CR (P = 0.002). Randomization to either CR diet was associated with significant improvements in emotional well-being/depression scores relative to control, with an average 8-week increase of 1.69 points (95% CI: 0.72, 2.66). CR diets are a safe/feasible way to achieve weight loss in people with MS and may be associated with improved emotional health.
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Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial.
Gardner, CD, Trepanowski, JF, Del Gobbo, LC, Hauser, ME, Rigdon, J, Ioannidis, JPA, Desai, M, King, AC
JAMA. 2018;319(7):667-679
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Obesity is a major public health challenge and different dietary strategies are employed to lose weight. This randomised clinical trial of 609 obese adults between the age of 18 and 50 aimed to determine the effects of a healthy low-fat diet in comparison to a healthy low-carbohydrate diet on weight change over a 12 month period. The study also assessed whether 3 genetic markers and blood sugar management affected weight loss in the 2 groups. Participants in the study were offered 22 group sessions of health coaching to support adherence to the programme. 481 participants completed the study. The low-carbohydrate group lost on average 6kg and the low-fat group lost on average 5.4kg. The difference between the 2 groups did not achieve significance for weight loss. There was also no significant genetic or blood sugar management effect in relation to dietary pattern and weight loss. The authors of this study conclude that the results of this study do not help in identifying which dietary type is better for whom in relation to 3 genetic markers and blood sugar management.
Abstract
Importance: Dietary modification remains key to successful weight loss. Yet, no one dietary strategy is consistently superior to others for the general population. Previous research suggests genotype or insulin-glucose dynamics may modify the effects of diets. Objective: To determine the effect of a healthy low-fat (HLF) diet vs a healthy low-carbohydrate (HLC) diet on weight change and if genotype pattern or insulin secretion are related to the dietary effects on weight loss. Design, Setting, and Participants: The Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) randomized clinical trial included 609 adults aged 18 to 50 years without diabetes with a body mass index between 28 and 40. The trial enrollment was from January 29, 2013, through April 14, 2015; the date of final follow-up was May 16, 2016. Participants were randomized to the 12-month HLF or HLC diet. The study also tested whether 3 single-nucleotide polymorphism multilocus genotype responsiveness patterns or insulin secretion (INS-30; blood concentration of insulin 30 minutes after a glucose challenge) were associated with weight loss. Interventions: Health educators delivered the behavior modification intervention to HLF (n = 305) and HLC (n = 304) participants via 22 diet-specific small group sessions administered over 12 months. The sessions focused on ways to achieve the lowest fat or carbohydrate intake that could be maintained long-term and emphasized diet quality. Main Outcomes and Measures: Primary outcome was 12-month weight change and determination of whether there were significant interactions among diet type and genotype pattern, diet and insulin secretion, and diet and weight loss. Results: Among 609 participants randomized (mean age, 40 [SD, 7] years; 57% women; mean body mass index, 33 [SD, 3]; 244 [40%] had a low-fat genotype; 180 [30%] had a low-carbohydrate genotype; mean baseline INS-30, 93 μIU/mL), 481 (79%) completed the trial. In the HLF vs HLC diets, respectively, the mean 12-month macronutrient distributions were 48% vs 30% for carbohydrates, 29% vs 45% for fat, and 21% vs 23% for protein. Weight change at 12 months was -5.3 kg for the HLF diet vs -6.0 kg for the HLC diet (mean between-group difference, 0.7 kg [95% CI, -0.2 to 1.6 kg]). There was no significant diet-genotype pattern interaction (P = .20) or diet-insulin secretion (INS-30) interaction (P = .47) with 12-month weight loss. There were 18 adverse events or serious adverse events that were evenly distributed across the 2 diet groups. Conclusions and Relevance: In this 12-month weight loss diet study, there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss. In the context of these 2 common weight loss diet approaches, neither of the 2 hypothesized predisposing factors was helpful in identifying which diet was better for whom. Trial Registration: clinicaltrials.gov Identifier: NCT01826591.
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Micronutrient Gaps in Three Commercial Weight-Loss Diet Plans.
G Engel, M, J Kern, H, Brenna, JT, H Mitmesser, S
Nutrients. 2018;10(1)
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Globally, around 39% of adults are overweight and 13% obese, and more than one third of American adults are obese. Being overweight or obese is associated with many chronic conditions, such as heart disease, high blood pressure and type 2 diabetes. Weight loss, even at moderate level, can reduce the risk of these obesity-related chronic conditions. Commercial weight-loss diet plans can vary greatly, not only in energy content but also in macronutrient and micronutrient composition. Most plans restrict calories or certain macronutrients, particularly carbohydrate or fat, and in doing so, often overlook micronutrient, i.e. vitamin and mineral, content. Previous studies have shown that many weight-loss plans do not provide adequate amounts of all micronutrients, and in order to reach the reference daily intakes for various vitamins and minerals, dieters would need to increase their calorie intake significantly and often unrealistically. The authors of this paper analysed seven single-day menus of three select commercial diet plans to determine their micronutrient sufficiency. The diet plans included were Eat to Live-Vegan, Aggressive Weight Loss (ETL-VAWL), Fast Metabolism Diet (FMD), and Eat, Drink and Be Healthy (EDH). ETL-VAWL diet provided less than 90% of recommended amounts for B12, B3, D, E, calcium, selenium and zinc. The FMD diet was low in B1, D, E, calcium, magnesium and potassium, while EDH diet didn’t meet the recommended amounts for vitamin D, calcium and potassium. Even after adjusting all the plans to an intake of 2000 kcal/day, several micronutrients were found to remain inadequate (vitamin B12 in ETL-VAWL, calcium in FMD and EDH and vitamin D in all diets). The authors conclude that, in order to reduce the risk of micronutrient deficiencies, more attention needs to be paid to micronutrient rich foods when designing commercial diet plans. Alternatively, these nutrient gaps should be filled in other ways, e.g. using appropriate dietary supplements.
Abstract
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.
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Effects of Providing High-Fat versus High-Carbohydrate Meals on Daily and Postprandial Physical Activity and Glucose Patterns: a Randomised Controlled Trial.
Parr, EB, Devlin, BL, Callahan, MJ, Radford, BE, Blankenship, JM, Dunstan, DW, Hawley, JA
Nutrients. 2018;10(5)
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The timing of habitual meal consumption and composition is known to be an important factor in health status, particularly for blood glucose regulation. The aim of this randomised crossover study was to assess the effects of altering meal timing and diet composition on postprandial glucose and physical activity levels. Eight overweight or obese men with a sedentary lifestyle completed two 12-day measurement periods including a 7-day habitual period followed by a 5-day experimental period, with an 8-day washout period. The two conditions tested were a high-fat, low carbohydrate diet (HFD) and a high-carbohydrate, low-fat diet (HCD) and participants were instructed to consume meals at standardised times throughout both conditions. Body composition, oxygen consumption and blood glucose were measured at baseline and between each experimental condition. This trial found the provision of meals did not alter overall activity patterns or postprandial activity patterns. The authors observed increased sedentary activity across the day, and identify evening time as an important target for sedentary time to be minimised. Based on these results, the authors suggest that future dietary interventions consider habitual meal consumption and composition to best replicate real-world behaviours.
Abstract
We determined the effects of altering meal timing and diet composition on temporal glucose homeostasis and physical activity measures. Eight sedentary, overweight/obese men (mean ± SD, age: 36 ± 4 years; BMI: 29.8 ± 1.8 kg/m²) completed two × 12-day (12-d) measurement periods, including a 7-d habitual period, and then 5 d of each diet (high-fat diet [HFD]: 67:15:18% fat:carbohydrate:protein versus high-carbohydrate diet [HCD]: 67:15:18% carbohydrate:fat:protein) of three meals/d at ±30 min of 0800 h, 1230 h, and 1800 h, in a randomised order with an 8-d washout. Energy intake (EI), the timing of meal consumption, blood glucose regulation (continuous glucose monitor system (CGMS)), and activity patterns (accelerometer and inclinometer) were assessed across each 12-d period. Meal provision did not alter the patterns of reduced physical activity, and increased sedentary behaviour following dinner, compared with following breakfast and lunch. The HCD increased peak (+1.6 mmol/L, p < 0.001), mean (+0.5 mmol/L, p = 0.001), and total area under the curve (+670 mmol/L/min, p = 0.001), as well as 3-h postprandial meal glucose concentrations (all p < 0.001) compared with the HFD. In overweight/obese males, the provision of meals did not alter physical activity patterns, but did affect glycaemic control. Greater emphasis on meal timing and composition is required in diet and/or behaviour intervention studies to ensure relevance to real-world behaviours.
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Randomised trial of coconut oil, olive oil or butter on blood lipids and other cardiovascular risk factors in healthy men and women.
Khaw, KT, Sharp, SJ, Finikarides, L, Afzal, I, Lentjes, M, Luben, R, Forouhi, NG
BMJ open. 2018;8(3):e020167
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Blood lipids is a term used for fatty substances found in the blood such as cholesterol and triglycerides. When these fatty substances are above a normal level it may increase an individual’s risk factors for coronary heart diseases. A diet high in saturated fats is linked to an increased amount of these fats in the blood. Recent renewed interest in the health effects of saturated fats based on their composition (long chain, medium chain, and short chain) brought about this randomised control trial. The aim of the study was to compare the effects of butter, extra virgin coconut oil and olive oil on blood lipids. The study population were men and women aged between 50 and 70 years who did not have any known medical history of heart disease or were on any medication related to heart disease. At the end of the four week trial period, significant changes in the blood lipids were observed within the three intervention groups. The concentration of LDL cholesterol in the butter group when compared with coconut oil and olive oil showed a significant increase, whilst no difference was observed in the LDL cholesterol concentration between the olive oil and coconut oil group. The concentration of HDL cholesterol in the coconut oil group increased significantly in comparison to the butter or olive oil group. However, the authors concluded that as further trials between different fatty acids and health are required, the current recommendation of the American Heart Association - to reduce saturated fat in general - is strongly recommended.
Abstract
INTRODUCTION High dietary saturated fat intake is associated with higher blood concentrations of low-density lipoprotein cholesterol (LDL-C), an established risk factor for coronary heart disease. However, there is increasing interest in whether various dietary oils or fats with different fatty acid profiles such as extra virgin coconut oil may have different metabolic effects but trials have reported inconsistent results. We aimed to compare changes in blood lipid profile, weight, fat distribution and metabolic markers after four weeks consumption of 50 g daily of one of three different dietary fats, extra virgin coconut oil, butter or extra virgin olive oil, in healthy men and women in the general population. DESIGN Randomised clinical trial conducted over June and July 2017. SETTING General community in Cambridgeshire, UK. PARTICIPANTS Volunteer adults were recruited by the British Broadcasting Corporation through their websites. Eligibility criteria were men and women aged 50-75 years, with no known history of cancer, cardiovascular disease or diabetes, not on lipid lowering medication, no contraindications to a high-fat diet and willingness to be randomised to consume one of the three dietary fats for 4 weeks. Of 160 individuals initially expressing an interest and assessed for eligibility, 96 were randomised to one of three interventions; 2 individuals subsequently withdrew and 94 men and women attended a baseline assessment. Their mean age was 60 years, 67% were women and 98% were European Caucasian. Of these, 91 men and women attended a follow-up assessment 4 weeks later. INTERVENTION Participants were randomised to extra virgin coconut oil, extra virgin olive oil or unsalted butter and asked to consume 50 g daily of one of these fats for 4 weeks, which they could incorporate into their usual diet or consume as a supplement. MAIN OUTCOMES AND MEASURES The primary outcome was change in serum LDL-C; secondary outcomes were change in total and high-density lipoprotein cholesterol (TC and HDL-C), TC/HDL-C ratio and non-HDL-C; change in weight, body mass index (BMI), waist circumference, per cent body fat, systolic and diastolic blood pressure, fasting plasma glucose and C reactive protein. RESULTS LDL-C concentrations were significantly increased on butter compared with coconut oil (+0.42, 95% CI 0.19 to 0.65 mmol/L, P<0.0001) and with olive oil (+0.38, 95% CI 0.16 to 0.60 mmol/L, P<0.0001), with no differences in change of LDL-C in coconut oil compared with olive oil (-0.04, 95% CI -0.27 to 0.19 mmol/L, P=0.74). Coconut oil significantly increased HDL-C compared with butter (+0.18, 95% CI 0.06 to 0.30 mmol/L) or olive oil (+0.16, 95% CI 0.03 to 0.28 mmol/L). Butter significantly increased TC/HDL-C ratio and non-HDL-C compared with coconut oil but coconut oil did not significantly differ from olive oil for TC/HDL-C and non-HDL-C. There were no significant differences in changes in weight, BMI, central adiposity, fasting blood glucose, systolic or diastolic blood pressure among any of the three intervention groups. CONCLUSIONS AND RELEVANCE Two different dietary fats (butter and coconut oil) which are predominantly saturated fats, appear to have different effects on blood lipids compared with olive oil, a predominantly monounsaturated fat with coconut oil more comparable to olive oil with respect to LDL-C. The effects of different dietary fats on lipid profiles, metabolic markers and health outcomes may vary not just according to the general classification of their main component fatty acids as saturated or unsaturated but possibly according to different profiles in individual fatty acids, processing methods as well as the foods in which they are consumed or dietary patterns. These findings do not alter current dietary recommendations to reduce saturated fat intake in general but highlight the need for further elucidation of the more nuanced relationships between different dietary fats and health. TRIAL REGISTRATION NUMBER NCT03105947; Results.
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Role of whole grains versus fruits and vegetables in reducing subclinical inflammation and promoting gastrointestinal health in individuals affected by overweight and obesity: a randomized controlled trial.
Kopf, JC, Suhr, MJ, Clarke, J, Eyun, SI, Riethoven, JM, Ramer-Tait, AE, Rose, DJ
Nutrition journal. 2018;17(1):72
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Poor diet is the leading risk factor for premature death and disability in the United States. Poor diets lead to metabolic syndrome and its associated diseases such as heart disease and diabetes. The purpose of this study was to determine the impact of increasing intake of wholegrains or fruit and vegetables against a typical Western diet on inflammatory makers and gut microbiota composition. The study was a randomized, parallel arm feeding trial which enrolled fifty-two participants. The subjects were randomized into three groups (control, wholegrains, and fruit and vegetables). Results indicate that the wholegrain and fruit and vegetable diets had significant positive impacts on inflammatory markers. Interestingly, while both treatment groups decreased inflammatory markers, each decreased a different biomarker. The treatments induced individualised changes in microbiota composition such that treatment group differences were not identified. Authors conclude that wholegrain and fruit and vegetable diets have a positive impact on metabolic health in individuals affected by overweight or obesity.
Abstract
BACKGROUND Whole grains (WG) and fruits and vegetables (FV) have been shown to reduce the risk of metabolic disease, possibly via modulation of the gut microbiota. The purpose of this study was to determine the impact of increasing intake of either WG or FV on inflammatory markers and gut microbiota composition. METHODS A randomized parallel arm feeding trial was completed on forty-nine subjects with overweight or obesity and low intakes of FV and WG. Individuals were randomized into three groups (3 servings/d provided): WG, FV, and a control (refined grains). Stool and blood samples were collected at the beginning of the study and after 6 weeks. Inflammatory markers [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), lipopolysaccharide binding protein (LBP), and high sensitivity C-reactive protein (hs-CRP)] were measured. Stool sample analysis included short/branched chain fatty acids (S/BCFA) and microbiota composition. RESULTS There was a significant decrease in LBP for participants on the WG (- 0.2 μg/mL, p = 0.02) and FV (- 0.2 μg/mL, p = 0.005) diets, with no change in those on the control diet (0.1 μg/mL, p = 0.08). The FV diet induced a significant change in IL-6 (- 1.5 pg/mL, p = 0.006), but no significant change was observed for the other treatments (control, - 0.009 pg/mL, p = 0.99; WG, - 0.29, p = 0.68). The WG diet resulted in a significant decrease in TNF-α (- 3.7 pg/mL; p < 0.001), whereas no significant effects were found for those on the other diets (control, - 0.6 pg/mL, p = 0.6; FV, - 1.4 pg/mL, p = 0.2). The treatments induced individualized changes in microbiota composition such that treatment group differences were not identified, except for a significant increase in α-diversity in the FV group. The proportions of Clostridiales (Firmicutes phylum) at baseline were correlated with the magnitude of change in LBP during the study. CONCLUSIONS These data demonstrate that WG and FV intake can have positive effects on metabolic health; however, different markers of inflammation were reduced on each diet suggesting that the anti-inflammatory effects were facilitated via different mechanisms. The anti-inflammatory effects were not related to changes in gut microbiota composition during the intervention, but were correlated with microbiota composition at baseline. TRIAL REGISTRATION ClinicalTrials.gov , NCT02602496 , Nov 4, 2017.
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Substituting whole grains for refined grains in a 6-wk randomized trial has a modest effect on gut microbiota and immune and inflammatory markers of healthy adults.
Vanegas, SM, Meydani, M, Barnett, JB, Goldin, B, Kane, A, Rasmussen, H, Brown, C, Vangay, P, Knights, D, Jonnalagadda, S, et al
The American journal of clinical nutrition. 2017;105(3):635-650
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Increased whole grain consumption has been associated with reduced levels of inflammation. This randomised, controlled trial aimed to assess the effects of a whole grain diet in comparison with a refined grain diet on the immune system, levels of inflammation and gut bacteria. 81 men and women aged between 40 and 60 were randomly assigned to either a whole grain or a refined grain diet for a period of 6 weeks. All other dietary components were kept the same and calorie levels were controlled to maintain weight levels. The study findings showed a positive effect on stool frequency and stool weight with the whole grain diet in comparison to the refined grain diet. The whole grain diet also showed modest positive effects on gut bacteria profiles and aspects of immunity. The whole grain diet showed no effects on markers of inflammation.
Abstract
Background: Observational studies suggest an inverse association between whole-grain (WG) consumption and inflammation. However, evidence from interventional studies is limited, and few studies have included measurements of cell-mediated immunity.Objective: We assessed the effects of diets rich in WGs compared with refined grains (RGs) on immune and inflammatory responses, gut microbiota, and microbial products in healthy adults while maintaining subject body weights.Design: After a 2-wk provided-food run-in period of consuming a Western-style diet, 49 men and 32 postmenopausal women [age range: 40-65 y, body mass index (in kg/m2) <35] were assigned to consume 1 of 2 provided-food weight-maintenance diets for 6 wk.Results: Compared with the RG group, the WG group had increased plasma total alkyresorcinols (a measure of WG intake) (P < 0.0001), stool weight (P < 0.0001), stool frequency (P = 0.02), and short-chain fatty acid (SCFA) producer Lachnospira [false-discovery rate (FDR)-corrected P = 0.25] but decreased pro-inflammatory Enterobacteriaceae (FDR-corrected P = 0.25). Changes in stool acetate (P = 0.02) and total SCFAs (P = 0.05) were higher in the WG group than in the RG group. A positive association was shown between Lachnospira and acetate (FDR-corrected P = 0.002) or butyrate (FDR-corrected P = 0.005). We also showed that there was a higher percentage of terminal effector memory T cells (P = 0.03) and LPS-stimulated ex vivo production of tumor necrosis factor-α (P = 0.04) in the WG group than in the RG group, which were positively associated with plasma alkylresorcinol concentrations.Conclusion: The short-term consumption of WGs in a weight-maintenance diet increases stool weight and frequency and has modest positive effects on gut microbiota, SCFAs, effector memory T cells, and the acute innate immune response and no effect on other markers of cell-mediated immunity or systemic and gut inflammation. This trial was registered at clinicaltrials.gov as NCT01902394.
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Vitamin D3 repletion versus placebo as adjunctive treatment of heart failure patient quality of life and hormonal indices: a randomized, double-blind, placebo-controlled trial.
Moretti, HD, Colucci, VJ, Berry, BD
BMC cardiovascular disorders. 2017;17(1):274
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A vitamin D deficiency in patients with heart failure (HF) seems to be associated with less favourable outcomes. Vitamin D status may influence several of the hormones that are important to keep the heart working normally. The objective of this study was to determine if vitamin D3 supplementation would replete vitamin D stores, improve the hormones b-type natriuretic peptide (BNP) and parathyroid hormone (PTH), improve heart and lung function, reduce inflammation, and improve quality of life (QOL) in HF patients. This was a 6 month randomised controlled trial, using a dose of 10,000 IU of vitamin D3 daily or a placebo, in 40 vitamin D deficient or insufficient (≤ 32 ng/ml) patients with stable HF. All variables were measured at baseline and 6 months. The change in BNP from baseline was +30pg/ml in the vitamin D group vs. +400pg/ml in the placebo group (p = 0.003). Vitamin D blood levels rose by 49ng/ml in the treatment group vs 4ng/ml in the placebo group (p < 0.001). Other measures of heart function were unchanged. The inflammatory marker high sensitivity C-reactive protein (hsCRP) remained unchanged for women, but modestly improved for men in the group given vitamin D. QOL scores significantly improved in the vitamin D group compared to placebo. The authors concluded that repletion of vitamin D may improve quality of life in heart failure patients and may help to normalise b-type natriuretic peptide, parathyroid hormone and high sensitivity C-reactive protein.
Abstract
BACKGROUND Vitamin D status may influence heart failure (HF) patient outcomes by affecting b-type natriuretic peptide (BNP), parathyroid hormone (PTH), and enhancing cardiac contractility. Vitamin D deficiency is associated with morbidity and mortality in HF patients. The objective of this study was to determine if vitamin D3 at a comparatively high dose would replete 25-hydroxyvitamin D (25(OH)D) stores, improve BNP, PTH, cardiopulmonary function, reduce inflammatory markers, and improve quality of life (QOL) in HF patients. METHODS This was a 6 month, parallel group, double-blind, placebo-controlled, single clinic center, randomized trial of supplemental vitamin D3 using a dose of 10,000 IU daily or placebo in 40 vitamin D deficient or insufficient (25(OH)D level ≤ 32 ng/ml) patients with stable New York Heart Association Class II-III HF in a specialty cardiology clinic. All variables were measured at baseline and 6 months. Values between the two treatment groups were assessed using Student's t-test or Mann-Whitney Test. Univariate analysis of covariance was conducted to adjust for variance in baseline 25(OH)D. RESULTS All results were adjusted for baseline 25(OH)D. The change in BNP from baseline was ∆ +30 ± 950 pg/ml for treatment vs. placebo ∆ +400 ± 1900 pg/ml, p = 0.003. 25(OH)D serum levels rose by 49 ± 32 ng/ml in the treatment group vs 4 ± 10 ng/ml in the placebo group, p < 0.001. PTH and exercise chronotropic response index improved in the treatment group vs placebo group, respectively, but both were attenuated by adjustment ((∆-20 ± 20 pg/ml vs ∆ + 7 ± 53 pg/ml respectively (p = 0.01, adjusted p = 0.07)) and (∆ + 0.13 ± 0.26 vs. ∆-0.03 ± 02.9 respectively, p < 0.01, adjusted p = 0.17)). Other measured cardiopulmonary parameters remained unchanged. High sensitivity C-reactive protein (hsCRP) remained unchanged for women, but improved for men (∆-2 ± 4 treatment versus ∆2 ± 5 mg/L placebo, p = 0.05). QOL scores, including composite overall and clinical summary scores significantly improved in treatment compared to placebo (∆ + 10 ± 15 versus -6 ± 15, p < 0.01 and ∆ + 8 ± 14 versus -8 ± 18, p = 0.01, respectively). CONCLUSIONS Repletion of 25(OH)D may improve QOL in HF patients and may help to normalize BNP, PTH, and hsCRP. TRIAL REGISTRATION Clinicaltrials.gov, Trial Registration Number: NCT01636570 , First registered 3 July 2012.