Greater Scores for Dietary Fat and Grain Quality Components Underlie Higher Total Healthy Eating Index-2015 Scores, While Whole Fruits, Seafood, and Plant Proteins Are Most Favorably Associated with Cardiometabolic Health in US Adults.

BACKGROUND: High-quality diets reduce the risk of cardiometabolic and other chronic diseases. The dietary components that distinguish higher from lower quality diets, and their associations with health, have not been fully investigated. OBJECTIVES: This study aimed to assess the component scores that underlie differences in total Healthy Eating Index (HEI)-2015 scores, quantify fatty acid (saturated, monounsaturated, polyunsaturated) intakes that comprise Fatty Acids component scores, and assess associations between component scores and cardiometabolic risk factors. METHODS: A cross-sectional analysis of data from the NHANES (2001-2016) was conducted. Total and component HEI-2015 scores were assessed in adult (≥19 y) participants who provided one 24-h dietary recall (n = 39,799). Survey-weighted mean component scores by quartile of total HEI-2015 score were determined. Regression analyses were conducted to assess fatty acid intakes across quartiles of Fatty Acids component scores. Separate regression analyses were conducted to assess associations between component scores and cardiometabolic risk factors, after adjusting for demographic characteristics and health behaviors. RESULTS: Scores for components related to dietary fat (Fatty Acids, Saturated Fats) and grain quality (Whole Grains, Refined Grains) accounted for the greatest differences in HEI-2015 scores. Higher Fatty Acids scores were primarily composed of lower saturated and greater polyunsaturated fat intakes. Whole Fruits, and Seafood and Plant Proteins, were most favorably associated with cardiometabolic risk factors including anthropometric measures (P < 0.001), systolic blood pressure (P < 0.01), glycemic markers (Whole Fruits only, P < 0.01), and HDL cholesterol and triglycerides (Seafood and Plant Proteins only, P < 0.001). CONCLUSIONS: Average diet quality in US adults is suboptimal. Higher quality diets are primarily distinguished by the types of fats and grain-based foods that are consumed. Interventions targeting dietary components that are most favorably associated with cardiometabolic risk factors-whole fruits, seafood, and plant proteins-may have the greatest impact on disease risk.

Circulating Concentrations of Essential Fatty Acids, Linoleic and α-Linolenic Acid, in US Adults in 2003-2004 and 2011-2012 and the Relation with Risk Factors for Cardiometabolic Disease: An NHANES Analysis.

BACKGROUND: The increased use of high-oleic oils to replace trans fat has led to concern about declining intake of PUFA and the potential for essential fatty acid insufficiency or even deficiency. OBJECTIVES: The aim of this study was to examine circulating concentrations of essential and poorly biosynthesized fatty acids, as biomarkers of dietary intake, in the NHANES data sets prior to (2003-2004 cycle) and following (2011-2012 cycle) legislation to reduce trans fat in the food supply and also to explore the associations between these fatty acids and markers of cardiometabolic health. METHODS: Fasting circulating concentrations of fatty acids from adults (aged ≥20 y) in the 2003-2004 and 2011-2012 NHANES cycles were used for analysis. Dietary data from one day of both the 2003-2004 and 2011-2012 cycles were used to examine differences in dietary fatty acid intake between these cycles. Regression analyses were used to assess relations between circulating concentrations of fatty acids and cardiometabolic health. RESULTS: Between 2003-2004 and 2011-2012, circulating concentrations of linoleic acid (LA) increased (1.38%, P = 0.002); no difference in dietary intake was observed. α-Linolenic acid (ALA), measured by dietary intake (0.14 g, P < 0.001) and circulating concentrations (0.23%, P < 0.01), increased from 2003-2004 to 2011-2012. Circulating LA was inversely associated with BMI (in kg/m2; regression coefficient per percentage point change in LA ± SE: -0.22 ± 0.04), waist circumference (-0.62 ± 0.09 cm), systolic blood pressure (-0.38 ± 0.09 mm Hg), triglycerides (-9.92 ± 0.63 mg/dL), glucose (-3.34 ± 0.13 mg/dL), insulin (-0.18 ± 0.05 µU/mL), and HOMA-IR (-0.29 ± 0.05). CONCLUSIONS: In a nationally representative sample of US adults, no declines in circulating concentrations of essential fatty acids, LA and ALA, were observed between 2003-2004 and 2011-2012, a time when high-oleic oils were increasingly used in the food supply. Higher amounts of circulating LA were correlated with lower risk of cardiometabolic dysfunction, which underscores the importance of monitoring consumption in the United States.

Corn Oil Lowers Plasma Cholesterol Compared with Coconut Oil in Adults with Above-Desirable Levels of Cholesterol in a Randomized Crossover Trial.

Background: Few trials have examined the effects of coconut oil consumption in comparison with polyunsaturated fatty acid-rich oils such as corn oil. Objective: This trial assessed the effects of consuming foods made with corn oil compared with coconut oil on lipids, glucose homeostasis, and inflammation. Methods: This was a preliminary randomized crossover study of men (n = 12) and women (n = 13) with a mean age of 45.2 y, mean body mass index (in kg/m2) of 27.7, fasting LDL cholesterol ≥115 mg/dL and <190 mg/dL, and triglycerides (TGs) ≤375 mg/dL. Subjects consumed muffins and rolls providing 4 tablespoons (∼54 g) per day of corn oil or coconut oil as part of their habitual diets for 4 wk, with a 3-wk washout between conditions. Fasting plasma lipids and high-sensitivity C-reactive protein (hs-CRP) and glucose metabolism were assessed via an intravenous glucose tolerance test at baseline and 15 and 29 d of treatment. Responses were compared between treatments by ANCOVA. Results: Median baseline concentrations of LDL cholesterol, non-HDL cholesterol, total cholesterol (total-C), HDL cholesterol, total-C:HDL cholesterol, and TGs were 123, 144, 188, 46.0, 4.21, and 92.5 mg/dL, respectively. Changes from baseline for corn oil and coconut oil conditions, respectively, were: LDL cholesterol (primary outcome; -2.7% compared with +4.6%), non-HDL cholesterol (-3.0% compared with +5.8%), total-C (-0.5% compared with +7.1%), HDL cholesterol (+5.4% compared with +6.5%), total-C:HDL cholesterol (-4.3% compared with -3.3%), and TGs (-2.1% compared with +6.0%). Non-HDL cholesterol responses were significantly different between corn and coconut oil conditions (P = 0.034); differences between conditions in total-C and LDL cholesterol approached significance (both P = 0.06). Responses for hs-CRP and carbohydrate homeostasis parameters did not differ significantly between diet conditions. Conclusions: When incorporated into the habitual diet, consumption of foods providing ∼54 g of corn oil/d produced a more favorable plasma lipid profile than did coconut oil in adults with elevated cholesterol. This trial was registered at clinicaltrials.gov as NCT03202654.

ω-6 Polyunsaturated Fatty Acids and Cardiometabolic Health: Current Evidence, Controversies, and Research Gaps.

The 2015 Dietary Guidelines for Americans recommend limiting the intake of saturated fatty acids (SFAs) to <10% of energy/d and replacing dietary SFAs with unsaturated fatty acids. A Presidential Advisory from the American Heart Association recently released its evaluation of the relation between dietary fats and cardiovascular disease (CVD), and also recommended a shift from SFAs to unsaturated fatty acids, especially polyunsaturated fatty acids (PUFAs), in conjunction with a healthy dietary pattern. However, the suggestion to increase the intake of PUFAs in general, and omega-6 (n-6) PUFAs in particular, continues to be controversial. This review was undertaken to provide an overview of the evidence and controversies regarding the effects of ω-6 PUFAs on cardiometabolic health, with emphasis on risks and risk factors for CVD (coronary heart disease and stroke) and type 2 diabetes mellitus (T2D). Results from observational studies show that higher intake of ω-6 PUFAs, when compared with SFAs or carbohydrate, is associated with lower risks for CVD events (10-30%), CVD and total mortality (10-40%), and T2D (20-50%). Findings from intervention studies on cardiometabolic risk factors suggest that ω-6 PUFAs reduce concentrations of LDL cholesterol and non-HDL cholesterol in a dose-dependent manner compared with dietary carbohydrate, and have a neutral effect on blood pressure. Despite the concern that ω-6 fatty acids increase inflammation, current evidence from studies in humans does not support this view. In conclusion, these findings support current recommendations to emphasize consumption of ω-6 PUFAs as a replacement of SFAs; additional randomized controlled trials with cardiometabolic disease outcomes will help to more clearly define the benefits and risks of this policy.