Archive

Research Area: Consumption

Trends in dietary carbohydrate, protein, and fat intake and diet quality among US adults, 1999-2016.

Shan, Z., C.D. Rehm, G. Rogers, M. Ruan, D.D.Wang, F.B. Hu, D. Mozaffarian, F.F. Zhang, S.N. Bhupathiraju, 2019. Trends in dietary carbohydrate, protein, and fat intake and diet quality among US adults, 1999-2016. JAMA. 322(12):1178-1187.

IMPORTANCE: Changes in the economy, nutrition policies, and food processing methods can affect dietary macronutrient intake and diet quality. It is essential to evaluate trends in dietary intake, food sources, and diet quality to inform policy makers. OBJECTIVE: To investigate trends in dietary macronutrient intake, food sources, and diet quality among US adults. DESIGN, SETTING, AND PARTICIPANTS: Serial cross-sectional analysis of the US nationally representative 24-hour dietary recall data from 9 National Health and Nutrition Examination Survey cycles (1999-2016) among adults aged 20 years or older. EXPOSURE: Survey cycle. MAIN OUTCOMES AND MEASURES: Dietary intake of macronutrients and their subtypes, food sources, and the Healthy Eating Index 2015 (range, 0-100; higher scores indicate better diet quality; a minimal clinically important difference has not been defined). RESULTS: There were 43,996 respondents (weighted mean age, 46.9 years; 51.9% women). From 1999 to 2016, the estimated energy from total carbohydrates declined from 52.5% to 50.5% (difference, −2.02%; 95% CI, −2.41% to −1.63%), whereas that of total protein and total fat increased from 15.5%to 16.4% (difference, 0.82%; 95% CI, 0.67%-0.97%) and from 32.0%to 33.2%(difference, 1.20%; 95% CI, 0.84%-1.55%), respectively (all P < .001 for trend). Estimated energy from low-quality carbohydrates decreased by 3.25% (95% CI, 2.74%-3.75%; P < .001 for trend) from 45.1%to 41.8%. Increases were observed in estimated energy from high-quality carbohydrates (by 1.23% [95% CI, 0.84%-1.61%] from 7.42% to 8.65%), plant protein (by 0.38% [95%CI, 0.28%-0.49%] from 5.38%to 5.76%), saturated fatty acids (by 0.36% [95% CI, 0.20%-0.51%] from 11.5% to 11.9%), and polyunsaturated fatty acids (by 0.65% [95% CI, 0.56%-0.74%] from 7.58%to 8.23%) (all P < .001 for trend). The estimated overall Healthy Eating Index 2015 increased from 55.7 to 57.7 (difference, 2.01; 95% CI, 0.86-3.16; P < .001 for trend). Trends in high- and low-quality carbohydrates primarily reflected higher estimated energy from whole grains (0.65%) and reduced estimated energy from added sugars (−2.00%), respectively. Trends in plant protein were predominantly due to higher estimated intake of whole grains (0.12%) and nuts (0.09%). CONCLUSIONS AND RELEVANCE: From 1999 to 2016, US adults experienced a significant decrease in percentage of energy intake from low-quality carbohydrates and significant increases in percentage of energy intake from high-quality carbohydrates, plant protein, and polyunsaturated fat. Despite improvements in macronutrient composition and diet quality, continued high intake of low-quality carbohydrates and saturated fat remained.

Health benefits of nut consumption in middle‐aged and elderly population.

Rusu, M.E., A. Mocan, I.C.F.R. Ferreira, D.-S. Popa, 2019. Health benefits of nut consumption in middle‐aged and elderly population. Antioxidants. 8, 302; doi:10.3390/antiox8080302.

Aging is considered the major risk factor for most chronic disorders. Oxidative stress and chronic inflammation are two major contributors for cellular senescence, downregulation of stress response pathways with a decrease of protective cellular activity and accumulation of cellular damage, leading in time to age‐related diseases. This review investigated the most recent clinical trials and cohort studies published in the last ten years, which presented the influence of tree nut and peanut antioxidant diets in preventing or delaying age‐related diseases in middle‐aged and elderly subjects (≥55 years old). Tree nut and peanut ingestion has the possibility to influence blood lipid count, biochemical and anthropometric parameters, endothelial function and inflammatory biomarkers, thereby positively affecting cardiometabolic morbidity and mortality, cancers, and cognitive disorders, mainly through the nuts’ healthy lipid profile and antioxidant and anti-inflammatory mechanisms of actions. Clinical evidence and scientific findings demonstrate the importance of diets characterized by a high intake of nuts and emphasize their potential in preventing age‐related diseases, validating the addition of tree nuts and peanuts in the diet of older adults. Therefore, increased consumption of bioactive antioxidant compounds from nuts clearly impacts many risk factors related to aging and can extend health span and lifespan.

Mechanisms underlying the cardiometabolic protective effect of walnut consumption in obese subjects: a cross‐over, randomized, double‐blinded, controlled inpatient physiology study.

Tuccinardi, D., O.M. Farr, J. Upadhyay, S.M. Oussaada, M.I. Klapa, M. Candela, S. Rampelli, S. Lehoux, I. Lázaro, A. Sala‐Vila, P. Brigidi, R.D. Cummings, C.S. Mantzoros, 2019. Mechanisms underlying the cardiometabolic protective effect of walnut consumption in obese subjects: a cross‐over, randomized, double‐blinded, controlled inpatient physiology study. Diabetes Obes Metab. 21(9):2086-2095.

Aims: To assess the effects of walnuts on cardiometabolic outcomes in obese subjects and to explore underlying mechanisms using novel methods including metabolomic, lipidomic, glycomic, and microbiome analysis integrated with lipid particle fractionation, appetite-regulating hormones and hemodynamic measurements. Materials and Methods: 10 obese subjects were enrolled in this cross-over, randomized, double-blind, placebo-controlled clinical trial. Patients participated in two 5-day inpatient stays during which they consumed a smoothie containing 48g walnuts or a macronutrient-matched placebo smoothie without nuts, with a one-month washout period between the two visits. Results: Walnut consumption improved aspects of the lipid profile, i.e. reduced fasting small and dense LDL particles (p<.02) and increased postprandial large HDL particles (p<.01). Lipoprotein Insulin Resistance Score, glucose and insulin AUC decreased significantly after walnut consumption (p<.01, p<.02, p<.04, respectively). Consuming walnuts significantly increased 10 N-glycans, with 8 of them carrying a fucose core. Lipidomic analysis showed a robust reduction in harmful ceramides, hexosylceramides and sphingomyelins, which have been shown to mediate effects on cardiometabolic risk. Peptide YY AUC significantly increased after walnut consumption (p<.03). No major significant changes in hemodynamic, metabolomic analysis or in host health-promoting bacteria such as Faecalibacterium were found. Conclusions: These data provide a more comprehensive mechanistic perspective of the effect of dietary walnut consumption on cardiometabolic parameters. Lipidomic and lipid nuclear magnetic resonance spectroscopy analysis showed an early but significant reduction in ceramides and other atherogenic lipids with walnut consumption that may explain the longer-term benefits of walnuts on insulin resistance, cardiovascular risk and mortality.

The resulting variation in nutrient intake with the inclusion of walnuts in the diets of adults at risk for type 2 diabetes: A randomized, controlled, crossover trial.

Njike, V.Y., V.C. Costales, P. Petraro, A. Annam, N. Yarandi, D.L. Katz, 2019. The resulting variation in nutrient intake with the inclusion of walnuts in the diets of adults at risk for type 2 diabetes: A randomized, controlled, crossover trial. Am J Health Promot. 33(3):430-438.

Purpose: We previously demonstrated that including walnuts in the diets of adults at risk for type 2 diabetes mellitus (T2DM) led to improved overall diet quality. This report examines the specific changes in their nutrient intake. Design: This was a randomized, controlled, modified Latin square parallel design trial with 2 treatment arms. Participants were randomized to walnut intake with, or without, dietary advice to regulate caloric intake. Within each treatment arm, they were further randomized to one of 2 sequence permutations (walnut-included/walnut-excluded or walnut-excluded/walnut-included diet), with a 3-month washout between treatment phases. Setting: Community hospital in Lower Naugatuck Valley in Connecticut. Participants: Cohort of 112 participants (31 men and 81 women) at risk for T2DM. Intervention: Participants included 56 g (366 kcal) of walnuts in their daily diets for 6 months. Measures: Nutrient intake was assessed using web-based Automated Self-Administered 24-Hour Dietary Assessment. Analysis: Data were analyzed using generalized linear models. Results: Walnut inclusion led to increased intake of total fat, calcium, magnesium, thiamin, total saturated fatty acids, and monounsaturated and polyunsaturated fatty acids (379.0 ± 90.3 g vs -136.5 ± 92.7 g, P < .01; 230.7 ± 114.2 mg vs -95.2 ± 117.4 mg, P = .05; 111.0 ± 33.9 mg vs -32.3 ± 34.9 mg, P < .01; 0.28 ± 0.2 mg vs -0.47 ± 0.2 mg, P = .02; 8.6 ± 3.4 g vs -1.1 ± 3.5 g, P =.05; 6.3 ± 3.9 g vs -6.3 ± 4.0 g, P = .03; and 25.4 ± 4.0 vs -6.6 ± 4.2 g, P < .01, respectively). Vitamin C intake decreased (-65.3 ± 55.3 mg vs 98.9 ± 56.8 mg, P = .04). Protein intake increased from baseline with the inclusion of walnuts (20.0 ± 8.8 g, P < .05). Walnut inclusion led to an increase in total calories consumed when caloric intake is not regulated. Conclusion: Including walnuts in the diets of these adults led to increased dietary intake of some nutrients associated with lower risk of developing T2DM and other cardiometabolic risk factors.