Cross-sectional measurement of adherence to a proposed sustainable and healthy dietary pattern among United States adults using the newly developed Planetary Health Diet Index for the United States
Background: Dietary choices are an important avenue for improving food system sustainability. The Planetary Health Diet was proposed by the EAT-Lancet Commission as a reference healthy and sustainable dietary pattern. Objectives: To assess adherence to the Planetary Health Diet among United States adults, this study developed and evaluated the Planetary Health Diet Index for the United States (PHDI-US), adapted from the original PHDI validated in the Brazilian population. Methods: The PHDI-US has 16 components with scores ranging between 0 and 150, and higher scores indicate better adherence to the Planetary Health Diet. Cross-sectional dietary data from 4741 participants of the National Health and Nutrition Examination Survey 2017-2018 were used to assess the validity and reliability of the PHDI-US. Results: Validity and reliability tests were acceptable overall: principal component analysis identified 6 components; total PHDI-US and Healthy Eating Index-2015 scores were positively associated (β = 0.67, standard error = 0.03, P <0.0001; R2 = 0.39); concurrent-criterion validity analyses identified significantly lower scores among males, everyday smokers, and younger adults; and the Cronbach's α value was 0.54. The average PHDI-US score was 46.7 out of 150, indicating that the diets of United States adults were far from meeting Planetary Health Diet recommendations. Based on component PHDI-US scores, many United States adults may be able to enhance the quality and sustainability of their diets by increasing intake of plant-based foods, including whole grains, nuts and peanuts, legumes, fruits, and vegetables, and reducing intake of animal-based foods, including red and processed meats. Conclusions: The PHDI-US is a new tool that can assess adherence to the Planetary Health Diet and identify key aspects of United States adults' diets that could be altered to potentially improve dietary sustainability and quality.
https://doi.org/10.1016/j.ajcnut.2023.09.009
A Dietary Model of Partial Meat Replacement with Walnuts Demonstrates Changes in the Nutrient Profile and Quality of the United States Population’s Diet.
The purpose of the study is to assess the impact of partial meat replacement with walnuts using a dose–escalation approach on nutrient intake and diet quality in the usual US diet. Food modeling was implemented using the nationally representative 2015–2018 National Health and Examination Survey (NHANES), with a focus on non-nut consumers, which included 2707 children and adolescents and 5190 adults. Walnuts replaced meat in a dose-escalating manner (0.5, 1, 1.5, and 2 oz walnuts per day replaced 1, 2, 3, and 4 oz meat, respectively). Diet quality was estimated using the population ratio method of the 2015 Healthy Eating Index. The usual intake of nutrients was estimated using the National Cancer Institute method. Significant differences were determined using non-overlapping 95% confidence intervals. The partial replacement of meat with walnuts demonstrated significant increases in the mean intake of fiber, magnesium, and omega-3 fatty acids and significant decreases in cholesterol and vitamin B12 in the modeled diets for children, adolescents, and adults. Additionally, the partial replacement of meat with walnuts improved overall diet quality. Walnut consumption at 1–2 oz as a replacement for some meat may improve nutrient intake and diet quality across age groups.
http://dx.doi.org/10.3390/nu15214518
Effect of a Mediterranean Diet or Mindfulness-Based Stress Reduction During Pregnancy on Child Neurodevelopment: A Prespecified Analysis of the IMPACT BCN Randomized Clinical Trial
Importance: Maternal suboptimal nutrition and high stress levels are associated with adverse fetal and childhood neurodevelopment. Objective: To test the hypothesis that structured interventions based on a Mediterranean diet or mindfulness-based stress reduction (MBSR) during pregnancy improve child neurodevelopment at age 2 years. Design, Setting, and Participants: This was a prespecified analysis of the parallel-group Improving Mothers for a Better Prenatal Care Trial Barcelona (IMPACT BCN) randomized clinical trial, which was conducted at a university hospital in Barcelona, Spain, from February 2017 to March 2020. A total of 1221 singleton pregnancies (19 to 23 weeks’ gestation) with high risk of delivering newborns who were small for gestational age were randomly allocated into 3 groups: a Mediterranean diet intervention, an MBSR program, or usual care. A postnatal evaluation with the Bayley Scales of Infant and Toddler Development, 3rd Edition (Bayley-III), was performed. Data were analyzed from July to November 2022. Interventions: Participants in the Mediterranean diet group received monthly individual and group educational sessions and free provision of extra virgin olive oil and walnuts. Those in the stress reduction group underwent an 8-week MBSR program adapted for pregnancy. Individuals in the usual care group received pregnancy care per institutional protocols. Main Outcomes and Measures: Neurodevelopment in children was assessed by Bayley-III at 24 months of corrected postnatal age. Results: A total of 626 children (293 [46.8%] female and 333 [53.2%] male) participated at a mean (SD) age of 24.8 (2.9) months. No differences were observed in the baseline characteristics between intervention groups. Compared with children from the usual care group, children in the Mediterranean diet group had higher scores in the cognitive domain (β, 5.02; 95% CI, 1.52-8.53; P = .005) and social-emotional domain (β, 5.15; 95% CI, 1.18-9.12; P = .01), whereas children from the stress reduction group had higher scores in the social-emotional domain (β, 4.75; 95% CI, 0.54-8.85; P = .02). Conclusions and Relevance : In this prespecified analysis of a randomized clinical trial, maternal structured lifestyle interventions during pregnancy based on a Mediterranean diet or MBSR significantly improved child neurodevelopmental outcomes at age 2 years. Trial Registration: ClinicalTrials.gov Identifier: NCT03166332
https://doi.org/10.1001/jamanetworkopen.2023.30255
Adding Walnuts to the Usual Diet Can Improve Diet Quality in the United States: Diet Modeling Study Based on NHANES 2015–2018.
Background: The under-consumption of calcium, potassium, fiber, and vitamin D is considered a U.S. public health concern. Shifts in eating patterns that increase the consumption of vegetables, fruits, whole grains, nuts/seeds, and dairy products can help achieve the recommended intakes of these nutrients, leading to healthier diets. Objective: We assessed the impact of adding 1 ounce (28.35 g) of walnuts to usual diets on diet quality and nutrients of concern, including magnesium, fiber, and potassium. Methods: We utilized 24 h dietary recalls obtained from the What We Eat in America, National Health and Nutrition Examination Survey (NHANES) and modeled the addition of 1 ounce (28.35 g) of walnuts to the usual diets of no-nut consumers. No-nut consumers aged ≥4 years (n = 7757) from the 2015–2018 NHANES study were included. Population percentages with intakes below the estimated average requirement (EAR) values for calcium, magnesium, folate, and vitamin E and above the adequate intake (AI) values for potassium and fiber were examined. Diet quality was assessed using the Healthy Eating Index-2015 (HEI-2015). The National Cancer Institute method was used to estimate the usual and modeled intakes. Significant differences between usual (current) and modeled intakes were determined using non-overlapping 95% confidence intervals. All analyses included sample weights to account for the NHANES survey design. Results: Adding 1 ounce (28.35 g) of walnuts to the usual diet resulted in significant reductions in the percentages of adults with intakes below the EAR for magnesium and folate (69.6% vs. 52.0%; 49.2% vs. 40.6%, respectively), and increased the percentage of adults above the AI for potassium (22.8% vs. 26.5%). A similar trend was observed among children (4–18 years). HEI scores improved significantly from 49.1 (95% CI: 48.0–50.4) to 58.5 (95% CI: 57.5–59.6) in children and from 52.4 (95% CI: 51.0–53.8) to 59.2 (95% CI: 58.0–60.5) in adults. Conclusions: Adding 1 ounce (28.35 g) of walnuts to the usual diet of no-nut consumers improved the diet quality and adequacy of some under-consumed nutrients. https://doi.org/10.3390/nu15020258
Is a Handful an Effective Way to Guide Nut Recommendations?
Dietary guidelines recommend consuming 30 g of nuts per day to reduce the risk of chronic disease. A 'handful' is commonly used to guide consumers. Research is lacking on how this translates into actual gram amounts. This study quantified the grams of nuts represented by different portion size measures, including a 'handful' and '30 g serving' among 120 participants. Each participant was randomised to a sequence where they received three of six different nut types (from almonds, cashews, hazelnuts, macadamias, peanuts, and walnuts) and were instructed to take a: 'usual serving', 'handful', 'small handful', 'large handful', and '30 g serving' of each. Combining all nut types, the median 'handful' was 36.3 g, compared to 28.7 g for the estimated '30 g serving' and 24.8 for the 'usual serving'. The 'large handful' was approximately double the 'handful' (61.3 g), whereas the 'small handful' was about half (16.7 g). Eighty-three percent of portions chosen were at least 80% of the recommended 30 g intake when participants were asked to take a 'handful', compared to 63% for the '30 g serving'. It appears a 'handful' can be used as a practical tool to guide recommended nut intakes, and increases the amount selected compared to instructions to take a '30 g serving'. https://doi.org/10.3390/ijerph18157812
The nutritional impact of replacing dietary meat with meat alternatives in the UK: A modelling analysis using nationally representative data.
Dietary patterns high in meat compromise both planetary and human health. Meat-alternatives may help facilitate meat reduction, however the nutritional implications of displacing meat with meat-alternatives does not appear to have been evaluated. Here, data from the 9th cycle of the National Diet and Nutrition Survey was used as the basis of models to assess the effect of meat substitution on nutritional intake. We implemented three models; model 1 progressively replaced 25%, 50%, 75%, or 100% of the current meat intake with a weighted mean of meat-alternatives available in the UK market. Model 2 compared different ingredient categories of meat-alternative; vegetable, mycoprotein, a combination of bean and pea, tofu, nut and soy. Model 3 compared fortified versus unfortified meat-alternatives. The models elicited significant shifts in nutrients. Overall, there were increases in carbohydrate, fibre, sugars and sodium, whereas reductions were found for protein, total and saturated fat, iron and B12. The greatest effects were seen for; vegetable-based (+24.63g/day carbohydrates), mycoprotein-based (−6.12g/day total fat), nut-based (−19.79g/day protein, +10.23g/day fibre; −4.80g/day saturated fat, +7.44g/day sugars), soy-based (+495.98mg/day sodium), and tofu-based (+7.63mg/day iron, −2.02μg/day B12). Our results suggest meat-alternatives can be a healthful replacement for meat if chosen correctly. Consumers should seek out meat-alternatives which are low in sodium and sugar, high in fibre, protein and with high micronutrient density, to avoid compromising nutritional intake if reducing their meat intake. Manufacturers and policy makers should consider fortification of meat-alternatives with nutrients such as iron and B12 and focus on reducing sodium and sugar content. https://doi.org/10.1017/S0007114521002750
Diet quality and risk and severity of COVID-19: a prospective cohort study.
Objective Poor metabolic health and certain lifestyle factors have been associated with risk and severity of coronavirus disease 2019 (COVID-19), but data for diet are lacking. We aimed to investigate the association of diet quality with risk and severity of COVID-19 and its intersection with socioeconomic deprivation. Design We used data from 592,571 participants of the smartphone-based COVID Symptom Study. Diet quality was assessed using a healthful plant-based diet score, which emphasizes healthy plant foods such as fruits or vegetables. Multivariable Cox models were fitted to calculate hazard ratios (HR) and 95% confidence intervals (95% CI) for COVID-19 risk and severity defined using a validated symptom-based algorithm or hospitalization with oxygen support, respectively. Results Over 3,886,274 person-months of follow-up, 31,815 COVID-19 cases were documented. Compared with individuals in the lowest quartile of the diet score, high diet quality was associated with lower risk of COVID-19 (HR, 0.91; 95% CI, 0.88-0.94) and severe COVID-19 (HR, 0.59; 95% CI, 0.47-0.74). The joint association of low diet quality and increased deprivation on COVID-19 risk was higher than the sum of the risk associated with each factor alone (Pinteraction=0.005). The corresponding absolute excess rate for lowest vs highest quartile of diet score was 22.5 (95% CI, 18.8-26.3) and 40.8 (95% CI, 31.7-49.8; 10,000 person-months) among persons living in areas with low and high deprivation, respectively. Conclusions A dietary pattern characterized by healthy plant-based foods was associated with lower risk and severity of COVID-19. These association may be particularly evident among individuals living in areas with higher socioeconomic deprivation. https://doi.org/10.1101/2021.06.24.21259283
The Relationship of Tree Nuts and Peanuts with Adiposity Parameters: A Systematic Review and Network Meta-Analysis.
The network meta-analysis and systematic review conducted aim to comparatively assess the effects of tree nuts and peanuts on body weight (BW), body mass index (BMI), waist circumference (WC), and body fat percentage (BF%). A systematic search up to 31 December 2020 was performed. A random-effects network meta-analysis was conducted following the PRISMA-NMA statement. A total of 105 randomized controlled trials (RCTs) with measures of BW (n = 6768 participants), BMI (n = 2918), WC (n = 5045), and BF% (n = 1226) were included. The transitivity assumption was met based on baseline characteristics. In the comparisons of nut consumption versus a control diet, there was no significant increase observed in any of the adiposity-related measures examined except for hazelnut-enriched diets, which raised WC. Moreover, almond-enriched diets significantly reduced WC compared to the control diet and to the pistachio-, mixed nuts-, and hazelnut-enriched diets. In subgroup analyses with only RCTs, designed to assess whether nut consumption affected weight loss, almonds were associated with reduced BMI and walnuts with reduced %BF. The evidence supports that: (1) tree nut and peanut consumption do not influence adiposity, and (2) compared to a control diet, the consumption of almond-enriched diets was associated with a reduced waist circumference. https://doi.org/10.3390/nu13072251
Minimal changes in telomere length after a 12-week dietary intervention with almonds in mid-age to older, overweight, and obese Australians: Results of a randomised clinical trial.
Diet is a modifiable risk factor for chronic disease and a potential modulator of telomere length (TL). The study aim was to investigate associations between diet quality and TL in Australian adults after a 12-week dietary intervention with an almond-enriched diet (AED). Participants (overweight/obese, 50–80 years) were randomised to an AED (n 62) or isoenergetic nut-free diet (NFD, n 62) for 12 weeks. Diet quality was assessed using a Dietary Guideline Index (DGI), applied to weighed food records, that consists of ten components reflecting adequacy, variety and quality of core food components and discretionary choices within the diet. TL was measured by quantitative PCR in samples of lymphocytes, neutrophils, and whole blood. There were no significant associations between DGI scores and TL at baseline. Diet quality improved with AED and decreased with NFD after 12 weeks (change from baseline AED + 9·8 %, NFD − 14·3 %; P < 0·001). TL increased in neutrophils (+9·6 bp, P = 0·009) and decreased in whole blood, to a trivial extent (–12·1 bp, P = 0·001), and was unchanged in lymphocytes. Changes did not differ between intervention groups. There were no significant relationships between changes in diet quality scores and changes in lymphocyte, neutrophil or whole blood TL. The inclusion of almonds in the diet improved diet quality scores but had no impact on TL mid-age to older Australian adults. Future studies should investigate the impact of more substantial dietary changes over longer periods of time.
https://doi.org/10.1017/S0007114521001549
Associations between nut intake, cognitive function and non-alcoholic fatty liver disease (NAFLD) in older adults in the United States: NHANES 2011-14
Background: Nuts are nutrient-rich and reported to provide some cognitive and cardiometabolic health benefits, but limited studies have focused on older adults. This study investigated the cross-sectional relationship between habitual nut intake, dietary pattern and quality, cognition and non-alcoholic fatty liver disease (NAFLD) in older adults.
Methods: Older adults (≥ 60 years) from the NHANES 2011-12 and 2013-14 cohorts, who had complete data on cognitive function (as CERAD total, delayed recall, animal fluency and digit-symbol substitution test) and variables to calculate the Fatty Liver Index (FLI), an indicator of NAFLD, were included (n = 1848). Nut intake and diet quality (Healthy Eating Index 2015) were determined using two 24-hour diet recalls. Participants were categorised into one of four groups based on their habitual nut intake: non-consumers (0 g/d), low intake (0.1-15.0 g/d), moderate intake (15.1-30.0 g/d) or met recommendation (> 30 g/d), with all outcomes compared between these nut intake groups.
Results: Cognitive scores of older adults were the lowest in non-consumers and significantly highest in the moderate intake group, with no further increase in those who consumed nuts more than 30 g/d (p < 0.007). FLI was the lowest among older adults with moderate nut intake but the associations disappeared after adjusting for covariates (p = 0.329). Moderate nut intake was also associated with better immediate and delayed memory in older adults with high risk of NAFLD (FLI ≥ 60) (B = 1.84 and 1.11, p < 0.05 respectively). Higher nutrient intake and better diet quality (p < 0.001) were seen with higher nut intake but did not influence energy from saturated fat intake. Factor analysis revealed 'Nuts and oils' as one of the four major dietary patterns associated with better cognition and lower FLI scores.
Conclusions: Moderate nut intake (15.1-30.0 g/d) may be sufficient for better cognitive performance, but not NAFLD risk of older adults in the US.
https://doi.org/10.1186/s12877-021-02239-1