Effects of a DASH-like diet containing lean beef on vascular health

Healthy Dietary Patterns with and without Meat Improved Cardiometabolic Disease Risk Factors in Adults: A Randomized Crossover Controlled Feeding Trial

We assessed the effects of consuming a U.S.-style healthy dietary pattern (HDP) with lean, unprocessed beef (BEEF) compared to a U.S.-style HDP without meat (vegetarian, VEG) on short-term changes in cardiometabolic disease (CMD) risk factors in adults classified as overweight or obese. Forty-one adults (22 females, 19 males; age 39.9 ± 8.0 y; BMI 29.6 ± 3.3 kg/m2; mean ± SD) completed two 5-week controlled feeding periods (randomized, crossover, controlled trial). For the BEEF HDP, two 3-oz (168-g) servings/d of lean, unprocessed beef were predominately substituted for some starchy vegetables and refined grains in the VEG HDP. Baseline and post-intervention measurements were fasting CMD risk factors, with serum low-density lipoprotein (LDL), total cholesterol (TC), and total apolipoprotein B as primary outcomes. VEG reduced LDL, insulin, and glucose compared to BEEF. Reductions did not differ between VEG vs. BEEF for TC, high-density lipoprotein (HDL), apolipoprotein A1, small, dense LDL IV, buoyant HDL2b, TC-to-HDL ratio, and systolic blood pressure. Total apolipoprotein B and all other CMD risk factors measured were not influenced by HDP type nor changed over time. Adopting a U.S.-style HDP that is either vegetarian or omnivorous with beef improved multiple cardiometabolic disease risk factors among adults classified as overweight or obese.

Effects of the Chinese heart-healthy diet (Sichuan cuisine) on lowering blood pressure in adults with hypertension: a randomized controlled feeding trial

BACKGROUND AND OBJECTIVES

Sichuan cuisine is characterized by high salt and oil content. We aimed to evaluate the effects of the Sichuan cuisine version of Chinese heart-healthy diet (CHH diet-SC) on blood pressure reduction among hypertensive adults.

METHODS AND STUDY DESIGN

The Chinese heart-healthy diet (CHH) trial was a multicenter randomized controlled feeding trial among Chinese hypertensive people. We conducted a secondary analysis of the CHH trial using data from the Sichuan center in Southwest China. Fifty-three people aged 25 to 75 years with a mean systolic blood pressure (SBP) between 130 and 159 mmHg were enrolled. Eligible participants underwent a 1-week run-in period with the typical local diet and were randomized 1:1 to consume the CHH diet-SC (n=27) or typical local diet (n=26) for the next 4-week. The primary outcome was the net change in SBP, the secondary outcomes included diastolic blood pressure (DBP), mean arterial pressure (MAP), and the rate of BP control.

RESULTS

Compared with the control group, the CHH diet-SC decreased cooking salt, oil, and red meat content and increased inclusion of whole grains, fruits, seafood, low-fat dairy, soybean, and nuts; the SBP experienced reductions of 7.54, 8.60, 9.14, and 10.1 mmHg at the end of weeks 1 through 4; the DBP was reduced 4.01 mmHg at week 4; the MAP was significantly reduced 6.02 mmHg finally; and rate of BP control significantly increased (p<0.05).

CONCLUSIONS

Adoption of the CHH diet-SC for 4 weeks can significantly reduce BP and increase the rate of BP control in hypertensive adults.

High- and normal-protein diets improve body composition and glucose control in adults with type 2 diabetes: a randomized trial

OBJECTIVE

Weight loss of ≥10% improves glucose control and may remit type 2 diabetes (T2D). High-protein (HP) diets are commonly used for weight loss, but whether protein sources, especially red meat, impact weight loss-induced T2D management is unknown. This trial compared an HP diet including beef and a normal-protein (NP) diet without red meat for weight loss, body composition changes, and glucose control in individuals with T2D.

METHODS

A total of 106 adults (80 female) with T2D consumed an HP (40% protein) diet with ≥4 weekly servings of lean beef or an NP (21% protein) diet excluding red meat during a 52-week weight loss intervention. Body weight, body composition, and cardiometabolic parameters were measured before and after intervention.

RESULTS

Weight loss was not different between the HP (-10.2 ± 1.6 kg) and NP (-12.7 ± 4.8 kg, p = 0.336) groups. Both groups reduced fat mass and increased fat-free mass percent. Hemoglobin A1c, glucose, insulin, insulin resistance, blood pressure, and triglycerides improved, with no differences between groups.

CONCLUSIONS

The lack of observed effects of dietary protein and red meat consumption on weight loss and improved cardiometabolic health suggests that achieved weight loss, rather than diet composition, should be the principal target of dietary interventions for T2D management.

The whole food beef matrix is more than the sum of its parts

Foods are not simply a delivery vehicle for nutrients; they consist of a matrix in which nutrients and non-nutrient compounds are presented that induce physiologic effects different from isolated nutrients. Dietary guidance is often based on effects of single nutrients that are considered unhealthy, such as saturated fat in beef. The purpose of this paper is to propose a working definition of the whole food beef matrix whose consumption has health effects distinct from those of isolated nutrients. The beef matrix can be defined as: the collective nutritive and non-nutritive components of the beef food structure and their unique chemical and physical interactions that may be important for human health which are distinguishable from those of the single components in isolation. Background information supporting this approach is summarized on multiple components provided by beef, temporal changes in beef consumption, dietary guidance that restricts beef, and how the background diet determines healthfulness rather than a single food. Examples of research are provided on other whole foods that differ from their constitutive nutrients and lay the groundwork for studies of beef as part of a healthy dietary pattern.

Greater adherence to healthy dietary patterns is associated with lower diastolic blood pressure and augmentation index in healthy, young adults

More than two-thirds of cardiovascular disease (CVD) deaths worldwide are attributable to dietary factors. Blood pressure variability (BPV), endothelial dysfunction, and arterial stiffness are important CVD risk factors. Although studies show a link between consuming a healthy diet and lower BPV and stiffness and improved endothelial function, research in young, healthy adults is scarce. We hypothesized that, in young, healthy adults, diet quality would be inversely associated with BPV and arterial stiffness and positively associated with endothelial function. This cross-sectional study included 56 healthy young adults (34 women/22 men, age 26.7 ± 0.8 years, body mass index 23.4 ± 0.4 kg/m2, blood pressure [BP] 113/69 mmHg). Three-day diet records were used to calculate two Dietary Approaches to Stop Hypertension (DASH) diet scores, the alternative Mediterranean Diet (aMED) score, and the Healthy Eating Index-2015 (HEI-2015) based on the 2015-2020 Dietary Guidelines for Americans. Twenty-four-hour ambulatory BP data were used to calculate average real variability of systolic and diastolic BP. Endothelial function was assessed by flow-mediated dilation, and arterial stiffness was assessed by pulse wave velocity and augmentation index (AIx). Overall, the HEI-2015 was inversely associated with 24-hour diastolic BP (DBP) and daytime DBP, and the aMED score was inversely associated with AIx. In our exploratory analyses, the Fung DASH score was inversely associated with 24-hour DBP and daytime DBP in women, but not men. These findings suggest that consuming a diet that aligns with the DASH diet, the Mediterranean diet, and/or the 2015-2020 Dietary Guidelines for Americans is associated with cardiovascular benefits in healthy, young adults.

Healthy U.S.-style dietary patterns can be modified to provide increased energy from protein

Background

Dietary patterns developed by the USDA provide modest levels of protein (14–18% energy) within the Acceptable Macronutrient Distribution Range (AMDR) of 10–35% for adults, though diets providing a higher percentage of energy may be beneficial for some individuals. The purpose of this study was to determine if it is feasible to modify the Healthy U.S.-Style Eating Pattern (“HEP”) to provide a higher percentage of energy from protein.

Methods

Using the framework implemented by the USDA in developing the HEP, energy from protein was set at 20%, 25%, and 30%. Amounts of protein foods were proportionally increased while amounts of other foods were adjusted iteratively within specified parameters. The models also disaggregated total meat/poultry into fresh and processed forms to develop patterns maintaining current proportions, current levels, reduced, or no processed meat/poultry. Nutrient intakes were compared with nutrient goals for representative U.S. populations with 2,000 kcal needs (females 19–30 years, males 51–70 years), with 90% of the Recommended Dietary Allowance or Adequate Intake regarded as sufficient.

Results

Dietary patterns with 20% energy from protein were constructed with minor deviations from the current 2,000 kcal HEP. Dietary patterns with 25% energy from protein were constructed for all levels of processed meat/poultry excluding the current proportion model, though relative to the current HEP the constructed patterns reflect substantial reductions in amounts of refined grains and starchy vegetables, and substantial increases in protein foods consumed as beans and peas, seafood, and soy products. It was not possible to develop a pattern with 30% energy from protein without reducing the percentage of energy from carbohydrate below the AMDR or non-compliance with other modeling constraints. Stepwise reductions in processed meat/poultry reduced sodium intake.

Conclusions

It is feasible to develop dietary patterns in a 2,000 kcal diet while mirroring the HEP that meet recommended intakes of nutrients with 20% or 25% energy from protein, though the pattern with 25% energy from protein may be more idealistic than realistic. Reduced levels of processed meat/poultry may translate to lower sodium intake.

Food as medicine? Exploring the impact of providing healthy foods on adherence and clinical and economic outcomes

Background

Methods

Results

Conclusion

Baseline Insulin Resistance Is a Determinant of the Small, Dense Low-Density Lipoprotein Response to Diets Differing in Saturated Fat, Protein, and Carbohydrate Contents

Individual responses to diet vary but causes other than genetics are poorly understood. This study sought to determine whether baseline values of homeostasis model assessment (HOMA-IR) was related to changes in small, dense low-density lipoprotein (sdLDL, i.e., LDL4, d = 1.044-1.063 g/mL) amounts quantified by isopycnic density profiling, in mildly hypercholesterolemic subjects (n = 27) consuming one of three low saturated fatty acid (SFA) diets: Dietary Approaches to Stop Hypertension (DASH), Beef in an Optimal Lean Diet (BOLD) and BOLD plus extra protein (BOLD+) when compared to a higher-SFA healthy American diet (HAD). The diets were consumed in random order for 5 wk, with 1 wk between diets. BOLD+ reduced fractional abundance (%) LDL4 (p < 0.05) relative to HAD, DASH and BOLD, and reductions in % LDL4 correlated with reductions in triglycerides (p = 0.044), total cholesterol (p = 0.014), LDL cholesterol (p = 0.004) and apolipoprotein B (p < 0.001). Responses to the four diets were similar (~12% decrease in % LDL4, p = 0.890) in the lower (<2.73 median) HOMA-IR subgroup but differed across diet conditions in the higher HOMA-IR subgroup (p = 0.013), in which % LDL4 was reduced with BOLD+ (-11%), was unchanged in BOLD and increased with the HAD (8%) and DASH (6%) diets (p < 0.05 for BOLD+ vs. HAD). Individual responses to diet interventions are influenced by presence and degree of insulin resistance as measured by HOMA-IR.

Effect of varying quantities of lean beef as part of a Mediterranean-style dietary pattern on lipids and lipoproteins: a randomized crossover controlled feeding trial

BACKGROUND

It remains unclear whether red meat consumption is causatively associated with cardiovascular disease (CVD) risk, and few randomized controlled studies have examined the effect of incorporating lean beef into a healthy dietary pattern.

OBJECTIVES

To evaluate the effects of a Mediterranean (MED) diet (carbohydrate 42%, protein 17%, fat 41%, SFAs 8%, MUFAs 26%, PUFAs 8%) with 14 (MED0.5; 0.5 oz), 71 (MED2.5; 2.5 oz), and 156 (MED5.5; 5.5 oz) g/d/2000 kcal lean beef compared with an average American diet (AAD; carbohydrate 52%, protein 15%, fat 33%, SFAs 12%, MUFAs 13%, PUFAs 8%) on lipid and lipoprotein concentrations, particle number, and size.

METHODS

This was a multicenter, 4-period controlled feeding, randomized crossover study. Fifty-nine generally healthy males and females (BMI 20-38 kg/m2; age 30-65 y) consumed each diet for 4 wk with a ≥1-wk washout between the diets. Fasting blood samples were collected at baseline and at the end of each 4-wk period. Lipid subfractions were measured by NMR.

RESULTS

Compared with the AAD, all 3 MED diets decreased LDL cholesterol (MED0.5: -10.3 mg/dL; 95% CI: -5.4, -15.7 mg/dL; MED2.5: -9.1 mg/dL; 95% CI: -3.9, -14.3 mg/dL; MED5.5: -6.9 mg/dL; 95% CI: -1.7, -12.1 mg/dL; P < 0.0001). All MED diets elicited similar reductions in total LDL particle number compared with baseline (P < 0.005); however, significant decreases only occurred with MED0.5 (-91.2 nmol/L; 95% CI: -31.4, -151.0 nmol/L) and MED2.5 (-85.3 nmol/L; 95% CI: -25.4, -145.2 nmol/L) compared with AAD (P < 0.003). Compared with the AAD, non-HDL cholesterol (P < 0.01) and apoB (P < 0.01) were lower following the 3 MED diets; there were no differences between the MED diets. All diets reduced HDL-cholesterol and HDL particle number from baseline (P < 0.01).

CONCLUSIONS

Lipid and lipoprotein lowering was not attenuated with the inclusion of lean beef in amounts ≤71 g (2.5 oz)/d as part of a healthy low-saturated-fat Mediterranean-style diet.This study is registered at clinicaltrials.gov as NCT02723617.

Association between diet quality indices and arterial stiffness in youth with type 1 diabetes: SEARCH for Diabetes in Youth Nutrition Ancillary Study

AIMS

We studied the association of three distinct diet quality indices and two measures of arterial stiffness in youth and young adults (YYA) aged 10 to 30 with T1D.

METHODS

Cross-sectional (n = 1421) and longitudinal (n = 520) analyses were conducted in T1D YYA participating in the SEARCH for Diabetes in Youth Study. The diet quality indices included the Dietary Approaches to Stop Hypertension (DASH) index, the Healthy Eating Index 2015 (HEI-2015), and a modified Mediterranean Diet Quality Index (mKIDMED). Arterial stiffness was measured with pulse wave velocity (PWV) and augmentation index (AIx) obtained using a SphygmoCor-Vx device and tonometer.

RESULTS

Average diet quality was moderate to poor, with mean scores of 41 (DASH, range 0-80), 55 (HEI-2015, range 0-100), 3.7 (mKIDMED, range - 3-12). None of the diet quality scores was associated with the central PWV or Aix, independent of demographic, clinical and lifestyle factors, body mass index and HbA1c. Longitudinal data yielded consistent findings with cross-sectional results.

CONCLUSIONS

This study suggests that diet quality may not function as an independent risk factor for arterial stiffening in YYA with T1D. These findings do not diminish the importance of consuming a quality diet for the management of diabetes, as demonstrated in previous work.

Dietary Approaches to Stop Hypertension (DASH) Diet and Blood Pressure Reduction in Adults with and without Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The Dietary Approaches to Stop Hypertension (DASH) diet is recognized as an effective dietary intervention to reduce blood pressure (BP). However, among randomized controlled trials (RCTs) investigating the DASH diet-mediated BP reduction, there are significant methodological and clinical differences. The purpose of this study was to comprehensively assess the DASH diet effect on BP in adults with and without hypertension, accounting for underlying methodological and clinical confounders. We systematically searched Medline and the Cochrane Collaboration Library databases and identified 30 RCTs (n = 5545 participants) that investigated the BP effects of the DASH diet compared with a control diet in hypertensive and nonhypertensive adults. Both random-effects and fixed-effect models were used to calculate the mean attained systolic BP (SBP) and diastolic BP (DBP) differences during follow-up. Subgroup and meta-regression analyses were also conducted. Compared with a control diet, the DASH diet reduced both SBP and DBP (difference in means: -3.2 mm Hg; 95% CI: -4.2, -2.3 mm Hg; P < 0.001, and -2.5 mm Hg; 95% CI: -3.5, -1.5 mm Hg; P < 0.001, respectively). Hypertension status did not modify the effect on BP reduction. The DASH diet compared with a control diet reduced SBP levels to a higher extent in trials with sodium intake >2400 mg/d than in trials with sodium intake ≤2400 mg/d, whereas both SBP and DBP were reduced more in trials with mean age <50 y than in trials of older participants. The quality of evidence was rated as moderate for both outcomes according to the Grading of Recommendations, Assessment, Development, and Evaluation approach. The adoption of the DASH diet was accompanied by significant BP reduction in adults with and without hypertension, although higher daily sodium intake and younger age enhanced the BP-lowering effect of the intervention. This meta-analysis was registered at www.crd.york.ac.uk/prospero as CRD42019128120.

Dietary Meat Categories and Descriptions in Chronic Disease Research Are Substantively Different within and between Experimental and Observational Studies: A Systematic Review and Landscape Analysis

This systematic review and landscape analysis describes patterns in dietary meat (skeletal muscle and associated tissues from mammalian, avian, and aquatic species; i.e., muscle foods) categories (CAT) and descriptions (DESCR) used throughout nutrition-related chronic disease literature, as there is anecdotally noted variation. A total of 1020 CAT and 776 DESCR were identified from 369 articles that assessed muscle food consumption and primary prevention of cardiovascular disease, obesity, type 2 diabetes, or cancer in adults ≥19 y from PubMed, Cochrane, and CINAHL up to March 2018. Specificity of CAT was analyzed on an empirical 1-7 ordinal scale as: 1) broad/undescriptive, "fish"; 2) muscle food type, "red meat"; 3) species, "poultry"; 4) broad + 1 descriptor, "processed meat"; 5) type/species + 1 descriptor, "fresh red meat"; 6) broad/type + 2 descriptors, "poached lean fish"; and 7) specific product, "luncheon meat." Median CAT specificity for randomized controlled trials (RCTs) and observational studies (OBSs) was 3 and 2 points out of 7, respectively, with no differences between chronic disease types. Specificity of OBS CAT was higher in recent articles but RCT CAT became less specific starting in the 2000s. RCT CAT were 400% more likely to include species, 500% more likely to include leanness, but 400% less likely to include processing degree compared with OBS CAT. A DESCR was included for 76% and 82% of OBS and RCT CAT, respectively. Researchers described processed meat, red meat, and total meat CAT more commonly than poultry or fish CAT. Among processed meat DESCR, 31% included a common term used in public regulatory definitions. In conclusion, muscle food categories and descriptions are substantively different within and between experimental and observational studies and do not match regulatory definitions. A practical muscle food classification system is warranted to improve interpretation of evidence regarding muscle food consumption and chronic disease.

A Calorie-Restricted DASH Diet Reduces Body Fat and Maintains Muscle Strength in Obese Older Adults

This study examined the effect of the Dietary Approaches to Stop Hypertension (DASH) diet containing lean red meat on measures of body composition and muscle strength in a cohort of obese adults 65 and older; 36 males (n = 15) and females (n = 21) consumed 1800 kcal/day for 12 weeks under controlled feeding conditions. The study diet included daily intakes of 126 g of meat. Measures of body composition and muscle strength were obtained at weeks 0, 3, 6, 9, and 12. Breakfast, lunch, and dinner were provided every day for 12 weeks, and equal portions of meat were distributed at each meal. Significant effects of the study diet were detected across time for total body weight, body mass index (BMI), waist circumference, hip circumference, body fat percentage, absolute fat mass (AFM), and blood pressure such that a decrease (p < 0.001) was observed over 12 weeks. Significant effects of the study diet were detected across time for sit/stand (p < 0.001) such that an increase was observed. From baseline to study end, total body weight decreased by 6.3% (p < 0.001), body fat percentage decreased by 2.5% (p < 0.001), and absolute fat mass (AFM) decreased by 4.4 kg (p < 0.001). By the study end, skeletal muscle mass (SMM) was positively correlated with handgrip strength (R2 = 0.75; p = 0.001) and resting energy expenditure (REE) (R2 = 0.29; p = 0.001). Handgrip strength, gait, balance, and resting energy expenditure (REE) were well maintained (p > 0.05) throughout the study. These findings suggest that the DASH diet has the potential to be a tool to preserve muscle strength while reducing fat mass in obese older adults.

Mediterranean-Style Diet Improves Systolic Blood Pressure and Arterial Stiffness in Older Adults

Supplemental Digital Content is available in the text.

We aimed to determine the effect of a Mediterranean-style diet, tailored to meet dietary recommendations for older adults, on blood pressure and arterial stiffness. In 12 months, randomized controlled trial (NU-AGE [New Dietary Strategies Addressing the Specific Needs of Elderly Population for Healthy Aging in Europe]), blood pressure was measured in 1294 healthy participants, aged 65 to 79 years, recruited from 5 European centers, and arterial stiffness in a subset of 225 participants. The intervention group received individually tailored standardized dietary advice and commercially available foods to increase adherence to a Mediterranean diet. The control group continued on their habitual diet and was provided with current national dietary guidance. In the 1142 participants who completed the trial (88.2%), after 1 year the intervention resulted in a significant reduction in systolic blood pressure (−5.5 mm Hg; 95% CI, −10.7 to −0.4; P=0.03), which was evident in males (−9.2 mm Hg, P=0.02) but not females (−3.1 mm Hg, P=0.37). The −1.7 mm Hg (95% CI, −4.3 to 0.9) decrease in diastolic pressure after intervention did not reach statistical significance. In a subset (n=225), augmentation index, a measure of arterial stiffness, was improved following intervention (−12.4; 95% CI, −24.4 to −0.5; P=0.04) with no change in pulse wave velocity. The intervention also resulted in an increase in 24-hour urinary potassium (8.8 mmol/L; 95% CI, 0.7–16.9; P=0.03) and in male participants (52%) a reduction in pulse pressure (−6.1 mm Hg; 95% CI, −12.0 to −0.2; P=0.04) and 24-hour urinary sodium (−27.1 mmol/L; 95% CI, −53.3 to −1.0; P=0.04). In conclusion, a Mediterranean-style diet is effective in improving cardiovascular health with clinically relevant reductions in blood pressure and arterial stiffness.

Red meat and dietary iron intakes are associated with some components of metabolic syndrome: Tehran Lipid and Glucose Study

BACKGROUND

This study was conducted to investigate whether the daily consumption of haem, non-haem, total iron and red meat can affect the occurrence of metabolic syndrome (MetS) and its components.

METHODS

Eligible adults (n = 4654) were selected from among participants of the Tehran Lipid and Glucose Study with an average follow-up of 3.8 years. Dietary intakes were assessed using a valid and reliable semi-quantitative food frequency questionnaire. Anthropometrics and biochemical variables were evaluated at baseline and follow-up examinations. The occurrence of MetS and its components were assessed in relation to haem, non-haem, total iron and red meat intakes.

RESULTS

There was no relationship between different types of dietary iron and red meat intakes and the incidence of MetS in the Tehranian population. Risk of hypertension decreased from quartiles 1 to 4 for haem iron (HR: 1.00, 0.92, 0.81, 0.80, P_trend < 0.01) and red meat intake (HR: 1.00, 0.89, 0.84, 0.77, P_trend < 0.01). The association between hyperglycemia and the fourth quartile of total iron intake was significant (HR = 1.98, 95% CI 1.08-3.63); and the risk of high triglyceride appeared to increase in higher quartiles of total iron intake (HR: 1.00, 1.17, 1.49, 1.75, P_trend = 0.01) compared to lower quartiles.

CONCLUSION

Our study suggests a potentially protective relationship of haem and moderate red meat intake against development of high blood pressure; and higher intake of total iron is related to hyperglycemia and high triglyceride.

Adopting a Mediterranean-Style Eating Pattern with Different Amounts of Lean Unprocessed Red Meat Does Not Influence Short-Term Subjective Personal Well-Being in Adults with Overweight or Obesity

Background

Reducing red meat intake is commonly recommended. Limited observational studies suggest that healthy eating patterns with red meat are associated with improved quality of life.

Objective

The secondary objectives of this randomized crossover controlled-feeding trial were to assess the effects of following a Mediterranean-style eating pattern (Med-Pattern) with different amounts of red meat on indexes of personal well-being (i.e., perceived quality of life, mood, and sleep) in overweight or obese adults. We hypothesized that following a Med-Pattern would improve these outcomes, independent of red meat intake amount.

Methods

Forty-one participants [aged 46 ± 2 y; body mass index (kg/m2): 30.5 ± 0.6; n = 28 women, n = 13 men) were provided Med-Pattern foods for two 5-wk periods separated by 4 wk of self-selected eating. The Med-Red Pattern contained ∼500 g/wk (typical US intake), and the Med-Control Pattern contained ∼200 g/wk (commonly recommended intake in heart-healthy eating patterns) of lean, unprocessed beef or pork compensated with mainly poultry and dairy. Baseline and postintervention outcomes measured were perceived quality of life via the MOS 36-Item Short-Form Health Survey, version 2 (SF-36v2), daily mood states via the Profile of Mood States (POMS), sleep perceptions via the Pittsburgh Sleep Quality Index, and sleep patterns via actigraphy. Data were analyzed via a doubly repeated-measures ANOVA adjusted for age, sex, and body mass at each time point.

Results

Following a Med-Pattern did not change domains of physical health, mental health, total mood disturbances, sleep perceptions, and sleep patterns but improved subdomains of physical health role limitations (SF-36v2: 93.6-96.7%; P = 0.038), vitality (SF-36v2: 57.9-63.0%; P = 0.020), and fatigue (POMS: 2.9-2.5 arbitrary units; P = 0.039). There were no differences between the Med-Red and Med-Control Patterns (time × pattern, P-interaction > 0.05).

Conclusion

Following a Med-Pattern, independent of lean, unprocessed red meat intake, may not be an effective short-term strategy to meaningfully improve indexes of personal well-being in adults who are overweight or obese. This trial was registered at clinicaltrials.gov as NCT02573129.

Short-Term Effects of Healthy Eating Pattern Cycling on Cardiovascular Disease Risk Factors: Pooled Results from Two Randomized Controlled Trials

Adherence to healthy eating patterns (HEPs) is often short-lived and can lead to repetitive attempts of adopting—but not maintaining—HEPs. We assessed effects of adopting, abandoning, and readopting HEPs (HEP cycling) on cardiovascular disease risk factors (CVD-RF). We hypothesized that HEP cycling would improve, worsen, and again improve CVD-RF. Data were retrospectively pooled for secondary analyses from two randomized, crossover, controlled feeding trials (n = 60, 52 ± 2 years, 30.6 ± 0.6 kg/m²) which included two 5–6 week HEP interventions (Dietary Approaches to Stop Hypertension-style or Mediterranean-style) separated by a four-week unrestricted eating period. Ambulatory and fasting blood pressures (BP), fasting serum lipids, lipoproteins, glucose, and insulin were measured before and during the last week of HEP interventions. Fasting systolic BP and total cholesterol decreased (−6 ± 1 mm Hg and −19 ± 3 mg/dL, respectively, p < 0.05), returned to baseline, then decreased again (−5 ± 1 mm Hg and −13 ± 3 mg/dL, respectively, p < 0.05) when adopting, abandoning, and readopting a HEP; magnitude of changes did not differ. Ambulatory and fasting diastolic BP and high-density lipoprotein cholesterol concentrations followed similar patterns; glucose and insulin remained unchanged. Low-density lipoprotein cholesterol concentrations decreased with initial adoption but not readoption (−13 ± 3 and −6 ± 3, respectively, interaction p = 0.020). Healthcare professionals should encourage individuals to consistently consume a HEP for cardiovascular health but also encourage them to try again if a first attempt is unsuccessful or short-lived.

A Mediterranean-style eating pattern with lean, unprocessed red meat has cardiometabolic benefits for adults who are overweight or obese in a randomized, crossover, controlled feeding trial

Background

A Mediterranean-style eating pattern (Mediterranean Pattern) is often described as being low in red meat. Research shows that lean, unprocessed red meat can be incorporated into healthy eating patterns to improve cardiometabolic disease (CMD) risk factors.

Objective

We assessed the effects of consuming different amounts of lean, unprocessed red meat in a Mediterranean Pattern on CMD risk factors. We hypothesized that consuming a Mediterranean Pattern would improve CMD risk factors and that red meat intake would not influence these improvements.

Design

In an investigator-blinded, randomized, crossover, controlled feeding trial, 41 subjects [mean ± SD age: 46 ± 2 y; mean ± SD body mass index (kg/m2): 30.5 ± 0.6] were provided with a Mediterranean Pattern for two 5-wk interventions separated by 4 wk of self-selected eating. The Mediterranean Patterns contained ∼500 g [typical US intake (Med-Red)] and ∼200 g [commonly recommended intake in heart-healthy eating patterns (Med-Control)] of lean, unprocessed beef or pork per week. Red meat intake was compensated by poultry and other protein-rich foods. Baseline and postintervention outcomes included fasting blood pressure, serum lipids, lipoproteins, glucose, insulin, and ambulatory blood pressure. The presented results were adjusted for age, sex, and body mass at each time point (P < 0.05).

Results

Total cholesterol decreased, but greater reductions occurred with Med-Red than with Med-Control (-0.4 ± 0.1 and -0.2 ±0.1 mmol/L, respectively, intervention × time = 0.045]. Low-density lipoprotein decreased with Med-Red but was unchanged with Med-Control [-0.3 ± 0.1 and -0.1 ± 0.1 mmol/L, respectively, intervention × time = 0.038], whereas high-density lipoprotein (HDL) concentrations decreased nondifferentially [-0.1 ± 0.0 mmol/L]. Triglycerides, total cholesterol:HDL, glucose, and insulin did not change with either Med-Red or Med-Control. All blood pressure parameters improved, except during sleep, independent of the red meat intake amount.

Conclusions

Adults who are overweight or moderately obese may improve multiple cardiometabolic disease risk factors by adopting a Mediterranean-style eating pattern with or without reductions in red meat intake when red meats are lean and unprocessed. This trial was registered at clinicaltrials.gov as NCT02573129.

Recent Science and Clinical Application of Nutrition to Coronary Heart Disease

One of the greatest threats to mortality in industrialized societies continues to be coronary heart disease (CHD). Moreover, the ability to decrease the incidence of CHD has reached a limit utilizing traditional diagnostic evaluations and prevention and treatment strategies for the top five cardiovascular risk factors (hypertension, diabetes mellitus, dyslipidemia, obesity, and smoking). It is well known that about 80% of CHD can be prevented with optimal nutrition, coupled with exercise, weight management, mild alcohol intake, and smoking cessation. Among all of these factors, optimal nutrition provides the basic foundation for prevention and treatment of CHD. Numerous prospective nutrition clinical trials have shown dramatic reductions in the incidence of CHD. As nutritional science and nutrigenomics research continues, our ability to adjust the best nutrition with an individualized approach is emerging. This article reviews the role of nutrition in the prevention and treatment of CHD and myocardial infarction (MI).

Healthy Dietary Patterns for Preventing Cardiometabolic Disease: The Role of Plant-Based Foods and Animal Products

Diets rich in plant foods are increasingly recommended to lower the risk of cardiometabolic diseases because of strong evidence that fruit, vegetables, legumes, whole grains, nuts, and seeds are protective. Although some animal products, such as unprocessed lean red meat, poultry, eggs, and dairy products, are recommended in dietary patterns to prevent cardiometabolic diseases, many health professionals advocate for exclusively plant-based dietary patterns. The aim of this article was to review recent evidence on the relative contributions of plant-based foods and animal products to a healthy dietary pattern. Secondary aims were to discuss current consumption patterns and adherence to dietary recommendations. Epidemiologic evidence suggests that a higher intake of plant-based foods is associated with a lower risk of cardiometabolic disease, whereas a higher meat intake increases the risk of cardiometabolic disease and the replacement of small quantities of animal protein with plant protein is associated with lower risk. Randomized controlled studies show that nutrient-dense diets containing animal protein, including some unprocessed lean meats, improve cardiovascular disease risk factors. Therefore, it is likely that the consumption of animal products, at recommended amounts, in the context of a dietary pattern that meets recommendations for fruit, vegetables, whole grains, nuts, seeds, and legumes, and does not exceed recommendations for added sugar, sodium, and saturated fat, may not increase cardiometabolic risk. Currently, adherence to these recommendations is suboptimal. Therefore, rather than debating the merits of healthy dietary patterns that are exclusively plant-based or that include animal sources in recommended amounts, the focus should be on improving overall eating patterns to align with dietary guidelines. Registered Dietitian/Nutritionists (RDNs) have the requisite nutrition expertise to facilitate change at the individual and population levels to promote adherence to healthy dietary patterns. Importantly, advocacy activities are urgently needed to create a healthier food environment, and all health professionals, including RDNs, must play a role.

Dietary poultry intake and the risk of stroke: A dose-response meta-analysis of prospective cohort studies

BACKGROUND & AIMS

We performed a meta-analysis to illuminate and quantify the potential relationship between poultry intake and risk of stroke through summarizing available evidence using a dose-response meta-analysis of prospective cohort studies.

METHODS

Pertinent prospective cohort studies attained using electronic searches through PubMed, and Scopus up to September 25th, 2017. Relative risks (RR) s with corresponding 95% confidence intervals (CIs) of the highest versus the lowest for cohort studies were evaluated using DerSimonian and Laird random-effects models to find combined RRs. We also assessed the dose-response effect of this relationship.

RESULTS

A total of 7 studies involving 354 718 participants were met inclusion criteria. The pooled RR of total stroke risk was [RR = 0.92 95% CI, 0.82, 1.03, I² = 19.8%, P_{heterogeneity} = 0.28] for the highest versus lowest categories of poultry intake. Subgroup analysis showed an inverse associations for the US people [RR = 0.86 95% CI, 0.77, 0.95, I² = 0.0%, P_{heterogeneity} = 0.38] and women [RR = 0.83, 95% CI, 0.72, 0.93, I² = 0.0%, P_{heterogeneity} = 0.63]. We did not obtain any significant association in the subtypes of strokes with highest versus lowest poultry intake [Ischemic stroke (RR = 0.91; 95% CI: 0.79, 1.02, I² = 0.0%, p = 0.93), Hemorrhagic (RR = 0.82; 95% CI: 0.59, 1.04, I² = 20.5%, P_{heterogeneity} = 0.28)]. One serving per week increment in poultry intake was not associated with the risk of stroke (RR: 1.00, 95% CI: 0.96, 1.03, I² = 69.0%, P_{heterogeneity} = 0.004). Nonlinear dose-response meta-analysis showed lower risk of stroke at consumption ∼1 serving/week.

CONCLUSION

Our meta-analysis revealed that poultry intake is not associated with total stroke risk; furthermore, an inverse relationship in US population and females must be interpreted with caution.

Food Groups and Risk of Hypertension: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies

The aim of this systematic review and meta-analysis was to summarize the evidence on the relation of the intakes of 12 major food groups, including whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages (SSBs) with the risk of hypertension. PubMed, Scopus, and Web of Science were searched systematically until June 2017 for prospective studies having quantitatively investigated the above-mentioned foods. We conducted meta-analysis on the highest compared with the lowest intake categories and linear and nonlinear dose-response meta-analyses to analyze the association. Summary RRs and 95% CIs were estimated by using a random-effects model. Overall, 28 reports were included in the meta-analysis. An inverse association for the risk of hypertension was observed for 30 g whole grains/d (RR: 0.92; 95% CI: 0.87, 0.98), 100 g fruits/d (RR: 0.97; 95% CI: 0.96, 0.99), 28 g nuts/d (RR: 0.70; 95% CI: 0.45, 1.08), and 200 g dairy/d (RR: 0.95; 95% CI: 0.94, 0.97), whereas a positive association for 100 g red meat/d (RR: 1.14; 95% CI: 1.02, 1.28), 50 g processed meat/d (RR: 1.12; 95% CI: 1.00, 1.26), and 250 mL SSB/d (RR: 1.07; 95% CI: 1.04, 1.10) was seen in the linear dose-response meta-analysis. Indication for nonlinear relations of the intakes of whole grains, fruits, fish, and processed meats with the risk of hypertension was detected. In summary, this comprehensive dose-response meta-analysis of 28 reports identified optimal intakes of whole grains, fruits, nuts, legumes, dairy, red and processed meats, and SSBs related to the risk of hypertension. These findings need to be seen under the light of very-low to low quality of meta-evidence. However, the findings support the current dietary guidelines in the prevention of hypertension.

Equivalent reductions in body weight during the Beef WISE Study: beef's role in weight improvement, satisfaction and energy

Objective

The objective of this randomized equivalence trial was to determine the impact of consuming lean beef as part of a high protein (HP) weight‐reducing diet on changes in body weight, body composition and cardiometabolic health.

Methods

A total of 120 adults (99 female) with overweight or obesity (BMI: 35.7 ± 7.0 kg m⁻²) were randomly assigned to consume either a HP diet with ≥4 weekly servings of lean beef (B; n = 60) or a HP diet restricted in all red meats (NB; n = 60) during a 16‐week weight loss intervention.

Results

Body weight was reduced by 7.8 ± 5.9% in B and 7.7 ± 5.5% in NB (p < 0.01 for both). Changes in percent body weight were equivalent between B and NB (mean difference: 0.06%, 90% confidence interval: (−1.7, 1.8)). Fat mass was reduced in both groups (p < 0.01; B: 8.0 ± 0.6 kg, NB: 8.6 ± 0.6 kg), while lean mass was not reduced in either group. Improvements in markers of cardiometabolic health (total cholesterol, low‐density lipoprotein cholesterol, triglycerides and blood pressure) were not different between B and NB.

Conclusion

Results of this study demonstrate that HP diets – either rich or restricted in red meat intakes – are effective for decreasing body weight and improving body composition and cardiometabolic health.

Red meat and chicken consumption and its association with high blood pressure and obesity in South Korean children and adolescents: a cross-sectional analysis of KSHES, 2011-2015

Background

The impact of meat consumption on high blood pressure (HBP) and obesity in children and adolescents is a subject of debate. The aim of this study was thus to evaluate the association between meat consumption and both HBP and obesity in this group.

Methods

We performed a cross-sectional analysis using nationally representative samples of children and adolescents aged 9, 12, and 15 years old (n = 136,739) who were included in the Korea School Health Examination Survey (KSHES) for the 2011–2015 period. Multiple linear and logistic regression analysis was used to determine the factors influencing systolic blood pressure (SBP), diastolic blood pressure (DBP), and body mass index (BMI, kg/m²) levels, and to test the strength of these relationships.

Results

Adjusted for covariates, 6.3% of those subjects who consumed >5 servings of meat (including beef, pork, and chicken) per week were obese, compared with 9.1% of the subjects who consumed <1 serving of meat/wk (obesity adjusted odds ratio [OR]: 1.44; 95% confidence interval [CI]: 1.21–1.70; P ≤0.001). Those who consumed <1 serving of meat/wk had an HBP prevalence of 8.2%, compared with 7.2% for subjects who consumed >5 servings of meat/wk (systolic HBP adjusted OR: 1.30; 95% CI: 1.05–1.62; P ≤0.01, diastolic HBP adjusted OR: 1.25; 95% CI: 1.02–1.54; P <0.05). Obese subjects were estimated to have a higher SBP (β = 7.497, P < 0.001) and DBP (β = 4.123, P <0.001) than subjects who had no excess weight. Compared to subjects who consumed >5 servings of meat/wk, those who consumed <3 servings of meat/wk had a higher SBP (β = 0.574, P <0.001) and DBP (β = 0.376, P = 0.003) after adjusting for BMI. The intake of milk, fruit, and vegetables was not associated with either SBP or DBP (P >0.05). In contrast, BMI was significantly associated with milk, fruits, and vegetables (P <0.01).

Conclusions

Among children and adolescents, a higher level of meat consumption was associated with lower SBP, DBP, and BMI, and greater height, suggesting that consuming an appropriate amount of meat is important for healthy growth at a young age.

Total red meat intake of ≥0.5 servings/d does not negatively influence cardiovascular disease risk factors: a systemically searched meta-analysis of randomized controlled trials

BACKGROUND

Observational associations between red meat intake and cardiovascular disease (CVD) are inconsistent. There are limited comprehensive analyses of randomized controlled trials (RCTs) that investigate the effects of red meat consumption on CVD risk factors.

OBJECTIVE

The purpose of this systematically searched meta-analysis was to assess the effects of consuming ≥0.5 or <0.5 servings of total red meat/d on CVD risk factors [blood total cholesterol (TC), LDL cholesterol, HDL cholesterol, triglycerides, ratio of TC to HDL cholesterol (TC:HDL), and systolic and diastolic blood pressures (SBP and DBP, respectively)]. We hypothesized that the consumption of ≥0.5 servings of total red meat/d would have a negative effect on these CVD risk factors.

DESIGN

Two researchers independently screened 945 studies from PubMed, Cochrane Library, and Scopus databases and extracted data from 24 qualified RCTs. Inclusion criteria were 1) RCT, 2) subjects aged ≥19 y, 3) consumption of ≥0.5 or <0.5 total red meat servings/d [35 g (1.25 ounces)], and 4) reporting ≥1 CVD risk factor. We performed an adjusted 2-factor nested ANOVA mixed-effects model procedure on the postintervention values of TC, LDL cholesterol, HDL cholesterol, TC:HDL cholesterol, triglycerides, SBP, and DBP; calculated overall effect sizes of change values; and used a repeated-measures ANOVA to assess pre- to postintervention changes.

RESULTS

Red meat intake did not affect lipid-lipoprotein profiles or blood pressure values postintervention (P > 0.05) or changes over time [weighted mean difference (95% CI): -0.01 mmol/L (-0.08, 0.06 mmol/L), 0.02 mmol/L (-0.05, 0.08 mmol/L), 0.03 mmol/L (-0.01, 0.07 mmol/L), and 0.04 mmol/L (-0.02, 0.10 mmol/L); -0.08 mm Hg (-0.26, 0.11 mm Hg); and -1.0 mm Hg (-2.4, 0.78 mm Hg) and 0.1 mm Hg (-1.2, 1.5 mm Hg) for TC, LDL cholesterol, HDL cholesterol, triglycerides, TC:HDL cholesterol, SBP, and DBP, respectively]. Among all subjects, TC, LDL cholesterol, HDL cholesterol, TC:HDL cholesterol, triglycerides, and DBP, but not SBP, decreased over time (P < 0.05).

CONCLUSIONS

The results from this systematically searched meta-analysis of RCTs support the idea that the consumption of ≥0.5 servings of total red meat/d does not influence blood lipids and lipoproteins or blood pressures.

The effect of dietary approaches to stop hypertension (DASH) diet on weight and body composition in adults: a systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND

Dietary approaches to stop hypertension (DASH) diet is rich in foods that are proposed to be inversely associated with obesity. Therefore, DASH might better affect body weight; however, published data are conflicting.

OBJECTIVE

To assess the effect of DASH on body weight and composition in adults.

METHODS

PubMed, EMBASE, Scopus and Google scholar were searched up to December 2015, for relevant randomized controlled clinical trials. Mean changes in body weight, body mass index (BMI) and waist circumference (WC) were extracted.

RESULTS

Thirteen articles (ten for body weight, six for BMI and two for WC) were eligible. Meta-analysis revealed that adults on DASH diet lose more weight (weighted mean difference [WMD] = -1.42 kg, 95% confidence interval [95%CI]: -2.03, -0.82) in 8-24 weeks, BMI (WMD = -0.42 kg m(-2) , 95%CI: -0.64, -0.20) in 8-52 weeks and WC (WMD = -1.05 cm, 95%CI: -1.61, -0.49) in 24 weeks compared with controls. Low caloric DASH led to even more weight reduction when compared with other low-energy diets. In addition, the effect was greater in overweight/obese participants and when compared with typical (Western or population's usual) diets.

CONCLUSION

DASH diet is a good choice for weight management particularly for weight reduction in overweight and obese participants.

Chemical Components and Meat Quality Traits Related to Palatability of Ten Primal Cuts from Hanwoo Carcasses

To determine chemical components and meat quality traits related to palatability of 10 primal cuts, 25 Hanwoo carcasses were selected from 5 carcasses × 5 quality grades and used to obtain proximate data and meat quality characteristics. Significant differences (p<0.05) in chemical component and meat quality were found among the 10 primal cuts. The highest fat content was found in the kalbi, followed by dungsim, yangjee, chaekeut, ansim, abdari, suldo, moksim, udun, and satae. Protein and moisture contents in the 10 primal cuts were in reverse order of fat content. Moksim had the highest drip loss % and cooking loss % than all other primal cuts while kalbi showed the lowest (p<0.05) percentage of drip and cooking loss. Ansim had the longest sarcomere length but the lowest shear force values than all other cuts (p<0.05). The highest (p<0.05) score for overall acceptability was observed in ansim. Moksim, udun, abdari, and satae were rated the lowest (p<0.05) in overall acceptability among the 10 primal cuts from Hanwoo carcasses. In conclusion, ansim, dungsim, chaekeut, and kalbi had the highest overall acceptability due to their higher fat contents and lower shear force values.

Plant protein and animal proteins: do they differentially affect cardiovascular disease risk?

Proteins from plant-based compared with animal-based food sources may have different effects on cardiovascular disease (CVD) risk factors. Numerous epidemiologic and intervention studies have evaluated their respective health benefits; however, it is difficult to isolate the role of plant or animal protein on CVD risk. This review evaluates the current evidence from observational and intervention studies, focusing on the specific protein-providing foods and populations studied. Dietary protein is derived from many food sources, and each provides a different composite of nonprotein compounds that can also affect CVD risk factors. Increasing the consumption of protein-rich foods also typically results in lower intakes of other nutrients, which may simultaneously influence outcomes. Given these complexities, blanket statements about plant or animal protein may be too general, and greater consideration of the specific protein food sources and the background diet is required. The potential mechanisms responsible for any specific effects of plant and animal protein are similarly multifaceted and include the amino acid content of particular foods, contributions from other nonprotein compounds provided concomitantly by the whole food, and interactions with the gut microbiome. Evidence to date is inconclusive, and additional studies are needed to further advance our understanding of the complexity of plant protein vs. animal protein comparisons. Nonetheless, current evidence supports the idea that CVD risk can be reduced by a dietary pattern that provides more plant sources of protein compared with the typical American diet and also includes animal-based protein foods that are unprocessed and low in saturated fat.

Type and amount of dietary protein in the treatment of metabolic syndrome: a randomized controlled trial

BACKGROUND

Food-based dietary patterns emphasizing plant protein that were evaluated in the Dietary Approaches to Stop Hypertension (DASH) and OmniHeart trials are recommended for the treatment of metabolic syndrome (MetS). However, the contribution of plant protein to total protein in these diets is proportionally less than that of animal protein.

OBJECTIVE

This study compared 3 diets varying in type (animal compared with plant) and amount of protein on MetS criteria.

DESIGN

Sixty-two overweight adults with MetS consumed a healthy American diet for 2 wk before being randomly allocated to either a modified DASH diet rich in plant protein (18% protein, two-thirds plant sources, n = 9 males, 12 females), a modified DASH diet rich in animal protein (Beef in an Optimal Lean Diet: 18.4% protein, two-thirds animal sources, n = 9 males, 11 females), or a moderate-protein diet (Beef in an Optimal Lean Diet Plus Protein: 27% protein, two-thirds animal sources, n = 10 males, 11 females). Diets were compared across 3 phases of energy balance: 5 wk of controlled (all foods provided) weight maintenance (WM), 6 wk of controlled weight loss (minimum 500-kcal/d deficit) including exercise (WL), and 12 wk of prescribed, free-living weight loss (FL). The primary endpoint was change in MetS criteria.

RESULTS

All groups achieved ∼5% weight loss at the end of the WL phase and maintained it through FL, with no between-diet differences (WM compared with WL, FL, P < 0.0001; between diets, P = NS). All MetS criteria decreased independent of diet composition (main effect of phase, P < 0.01; between diets, P = NS). After WM, all groups had a MetS prevalence of 80-90% [healthy American diet (HAD) compared with WM, P = NS], which decreased to 50-60% after WL and was maintained through FL (HAD, WM vs WL, FL, P < 0.01).

CONCLUSIONS

Weight loss was the primary modifier of MetS resolution in our study population regardless of protein source or amount. Our findings demonstrate that heart-healthy weight-loss dietary patterns that emphasize either animal or plant protein improve MetS criteria similarly. This study was registered at clinicaltrials.gov as NCT00937638.

Dietary Approaches to Stop Hypertension diet retains effectiveness to reduce blood pressure when lean pork is substituted for chicken and fish as the predominant source of protein

BACKGROUND

Hypertension is a major, modifiable risk factor for cardiovascular and kidney disease and premature mortality that is improved by the DASH (Dietary Approaches to Stop Hypertension) diet. The DASH diet emphasizes increased consumption of fruit and vegetables, whole grains, low-fat dairy, nuts, and poultry and fish and reduced intakes of fats, red meats (including pork), sodium, and added sugars.

OBJECTIVE

We sought to evaluate whether the consumption of lean pork compared with the consumption of chicken and fish as the predominant protein source in a DASH-style diet affected blood pressure (BP) control in men and women with elevated BP.

DESIGN

In a randomized crossover study, 13 women and 6 men [mean ± SEM age: 61 ± 2 y; BMI (in kg/m²): 31.2 ± 1.4] with elevated BP [systolic blood pressure (SBP)/diastolic blood pressure (DBP): 130 ± 2/85 ± 2 mm Hg] consumed a DASH-style diet for two 6-wk controlled dietary interventions (with a 4-wk diet washout between interventions) with either lean pork [DASH diet with pork (DASH-P)] or chicken and fish [DASH diet with chicken and fish (DASH-CF), the control diet] as the major protein source (55% of total protein intake). SBP and DBP were measured manually and with a 24-h BP monitoring system on 3 d before and 3 d at the end of each diet intervention.

RESULTS

Preintervention manual BP (DASH-P: 130/84 ± 2/1 mm Hg; DASH-CF: 129/84 ± 2/1 mg Hg) and postintervention manual BP (DASH-P: 122/79 ± 2/1 mm Hg; DASH-CF: 123/78 ± 3/1) were not different between the DASH-P and DASH-CF. Consumption of these DASH-style diets for 6 wk reduced all measures of BP (P < 0.05) with no differences in responses between the DASH-CF and DASH-P.

CONCLUSION

The results indicate that adults with elevated BP may effectively incorporate lean pork into a DASH-style diet for BP reduction.

Research gaps in evaluating the relationship of meat and health

Humans evolved as omnivores and it has been proposed that cooking meat allowed for evolution of larger brains that has led to our success as a species. Meat is one of the most nutrient dense foods, providing high-quality protein, heme iron, zinc, and vitamins B6 and B12. Despite these advantages, epidemiologic studies have linked consumption of red or processed meat with obesity, type 2 diabetes, cardiovascular diseases, and cancers of multiple organs. Most observational studies report small, increased relative risks. However, there are many limitations of such studies including inability to accurately estimate intake, lack of prespecified hypotheses, multiple comparisons, and confounding from many factors - including body weight, fruit/vegetable intake, physical activity, smoking, and alcohol - that correlate significantly either positively or negatively with meat intake and limit the reliability of conclusions from these studies. The observational studies are heterogeneous and do not fulfill many of the points proposed by AB Hill in 1965 for inferring causality; his most important factor was strength of the association which in dietary studies is usually <1.5 but is not considered adequate in virtually all other areas of epidemiology outside nutrition. Accepting small, statistically significant risks as "real" from observational associations, the field of nutrition has a long list of failures including beta-carotene and lung cancer, low-fat diets and breast cancer or heart disease that have not been confirmed in randomized trials. Moderate intake of a variety of foods that are enjoyed by people remains the best dietary advice.

Dietary protein intake and coronary heart disease in a large community based cohort: results from the Atherosclerosis Risk in Communities (ARIC) study [corrected]

Background

Prospective data examining the relationship between dietary protein intake and incident coronary heart disease (CHD) are inconclusive. Most evidence is derived from homogenous populations such as health professionals. Large community-based analyses in more diverse samples are lacking.

Methods

We studied the association of protein type and major dietary protein sources and risk for incident CHD in 12,066 middle-aged adults (aged 45–64 at baseline, 1987–1989) from four U.S. communities enrolled in the Atherosclerosis Risk in Communities (ARIC) Study who were free of diabetes mellitus and cardiovascular disease at baseline. Dietary protein intake was assessed at baseline and after 6 years of follow-up by food frequency questionnaire. Our primary outcome was adjudicated coronary heart disease events or deaths with following up through December 31, 2010. Cox proportional hazard models with multivariable adjustment were used for statistical analyses.

Results

During a median follow-up of 22 years, there were 1,147 CHD events. In multivariable analyses total, animal and vegetable protein were not associated with an increased risk for CHD before or after adjustment. In food group analyses of major dietary protein sources, protein intake from red and processed meat, dairy products, fish, nuts, eggs, and legumes were not significantly associated with CHD risk. The hazard ratios [with 95% confidence intervals] for risk of CHD across quintiles of protein from poultry were 1.00 [ref], 0.83 [0.70–0.99], 0.93 [0.75–1.15], 0.88 [0.73–1.06], 0.79 [0.64–0.98], P for trend  = 0.16). Replacement analyses evaluating the association of substituting one source of dietary protein for another or of decreasing protein intake at the expense of carbohydrates or total fats did not show any statistically significant association with CHD risk.

Conclusion

Based on a large community cohort we found no overall relationship between protein type and major dietary protein sources and risk for CHD.