Abstract Purpose Many dietary factors have either proinflammatory or anti-inflammatory properties. We previously developed a dietary inflammatory index (DII) to assess the inflammatory potential of ...diet. In this study, we conducted a construct validation of the DII based on data from a food frequency questionnaire and three inflammatory biomarkers in a subsample of 2567 postmenopausal women in the Women's Health Initiative Observational Study. Methods We used multiple linear and logistic regression models, controlling for potential confounders, to test whether baseline DII predicted concentrations of interleukin-6, high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor alpha receptor 2, or an overall biomarker score combining all three inflammatory biomarkers. Results The DII was associated with the four biomarkers with beta estimates (95% confidence interval) comparing the highest with lowest DII quintiles as follows: interleukin-6: 1.26 (1.15–1.38), Ptrend < .0001; tumor necrosis factor alpha receptor 2: 81.43 (19.15–143.71), Ptrend = .004; dichotomized hs-CRP (odds ratio for higher vs. lower hs-CRP): 1.30 (0.97–1.67), Ptrend = .34; and the combined inflammatory biomarker score: 0.26 (0.12–0.40), Ptrend = .0001. Conclusions The DII was significantly associated with inflammatory biomarkers. Construct validity of the DII indicates its utility for assessing the inflammatory potential of diet and for expanding its use to include associations with common chronic diseases in future studies.
Direct assessment of skeletal muscle mass in older adults is clinically challenging. Relationships between lean mass and late-life outcomes have been inconsistent. The D3-creatine dilution method ...provides a direct assessment of muscle mass.
Muscle mass was assessed by D3-creatine (D3Cr) dilution in 1,382 men (mean age, 84.2 years). Participants completed the Short Physical Performance Battery (SPPB); usual walking speed (6 m); and dual x-ray absorptiometry (DXA) lean mass. Men self-reported mobility limitations (difficulty walking 2-3 blocks or climbing 10 steps); recurrent falls (2+); and serious injurious falls in the subsequent year. Across quartiles of D3Cr muscle mass/body mass, multivariate linear models calculated means for SPPB and gait speed; multivariate logistic models calculated odds ratios for incident mobility limitations or falls.
Compared to men in the highest quartile, those in the lowest quartile of D3Cr muscle mass/body mass had slower gait speed (Q1: 1.04 vs Q4: 1.17 m/s); lower SPPB (Q1: 8.4 vs Q4: 10.4 points); greater likelihood of incident serious injurious falls (odds ratio OR Q1 vs Q4: 2.49, 95% confidence interval CI: 1.37, 4.54); prevalent mobility limitation (OR Q1 vs Q4,: 6.1, 95% CI: 3.7, 10.3) and incident mobility limitation (OR Q1 vs Q4: 2.15 95% CI: 1.42, 3.26); p for trend < .001 for all. Results for incident recurrent falls were in the similar direction (p = .156). DXA lean mass had weaker associations with the outcomes.
Unlike DXA lean mass, low D3Cr muscle mass/body mass is strongly related to physical performance, mobility, and incident injurious falls in older men.
Sarcopenia is defined as an age-related decrease in muscle mass and performance. Several consensus definitions of sarcopenia exist, each providing different cut points and methodologies for assessing ...muscle mass and muscle strength. Thus, wide variation in the prevalence of sarcopenia has been reported, generally ranging up to 45% for men and 26% for women. Risk factors for sarcopenia include age, malnutrition, and physical inactivity. Additional evidence suggests a protective role for protein supplementation in older adults to preserve lean body mass and prevent frailty, accepted intervention targets for reducing the risk of sarcopenia. Protein supplements vary widely in their composition, and small trials of heterogeneous study designs have made it difficult to extrapolate findings to develop data-driven, evidence-based recommendations for protein supplementation in sarcopenia prevention. Short-term randomized controlled trials of muscle protein synthesis have demonstrated that whey protein increases synthesis more so than casein or soy isolates. Studies also suggest that essential amino acids stimulate muscle protein synthesis to a greater extent than nonessential amino acids. This review summarizes the epidemiological and clinical trial evidence establishing the current definitions for sarcopenia and provides an overview of the state of the evidence for protein supplementation to prevent and/or mitigate sarcopenia.
A high glycemic index (GI) and glycemic load (GL) diet may stimulate acne proliferative pathways by influencing biochemical factors associated with acne. However, few randomized controlled trials ...have examined this relationship, and this process is not completely understood.
This study examined changes in biochemical factors associated with acne among adults with moderate to severe acne after following a low GI and GL diet or usual eating plan for 2 weeks.
This study utilized a parallel randomized controlled design to compare the effect of a low GI and GL diet to usual diet on biochemical factors associated with acne (glucose, insulin, insulin-like growth factor IGF-1, and insulin-like growth factor binding protein IGFBP-3) and insulin resistance after 2 weeks.
Sixty-six participants were randomly allocated to the low GI and GL diet (n=34) or usual eating plan (n=32) and included in the analyses.
The primary outcomes were biochemical factors of acne and insulin resistance with dietary intake as a secondary outcome.
Independent sample t tests assessed changes in biochemical factors associated with acne, dietary intake, and body composition pre- and postintervention, comparing the two dietary interventions.
IGF-1 concentrations decreased significantly among participants randomized to a low GI and GL diet between pre- and postintervention time points (preintervention=267.3±85.6 mg/mL, postintervention=244.5±78.7 ng/mL) (P=0.049). There were no differences in changes in glucose, insulin, or IGFBP-3 concentrations or insulin resistance between treatment groups after 2 weeks. Carbohydrate (P=0.019), available carbohydrate (P<0.001), percent energy from carbohydrate (P<0.001), GI (P<0.001), and GL (P<0.001) decreased significantly among participants following a low GI/GL diet between the pre- and postintervention time points. There were no differences in changes in body composition comparing groups.
In this study, a low GI and GL diet decreased IGF-1 concentrations, a well-established factor in acne pathogenesis. Further research of a longer duration should examine whether a low GI and GL diet would result in a clinically meaningful difference in IGF-1 concentrations leading to a reduction in acne. This trial was registered at clinicaltrials.gov as NCT02913001.
Animal models support a role for the gut microbiota in the development of hypertension. There has been a lack of epidemiological cohort studies to confirm these findings in human populations. We ...examined cross-sectional associations between measures of gut microbial diversity and taxonomic composition and blood pressure (BP) in 529 participants of the biracial (black and white) CARDIA study (Coronary Artery Risk Development in Young Adults). We sequenced V3-V4 regions of the 16S ribosomal RNA marker gene using DNA extracted from stool samples collected at CARDIA’s Year 30 follow-up examination (2015–2016; aged 48–60 years). We quantified associations between BP (hypertension defined as systolic BP ≥140 mm Hg or diastolic BP ≥90 mm Hg or antihypertension medication use and systolic BP) and within and between-person diversity measures. We conducted genera-specific multivariable-adjusted regression analysis, accounting for multiple comparisons using the false discovery rate. Hypertension and systolic BP were inversely associated with measures of α-diversity, including richness and the Shannon Diversity Index, and were distinguished with respect to principal coordinates based on a similarity matrix of genera abundance. Several specific genera were significantly associated with hypertension and systolic BP, though results were attenuated with adjustment for body mass index. Our findings support associations between within-person and between-person gut microbial community diversity and taxonomic composition and BP in a diverse population-based cohort of middle-aged adults. Future study is needed to define functional pathways that underlie observed associations and identify specific microbial targets for intervention.
This study aimed to shed light on contradictory associations of alcohol intake with waist circumference (WC) and body mass index (BMI) by examining 5-yr changes in alcohol intake in relation to 5-yr ...WC and BMI changes.
This prospective study included 4,355 participants (1,974 men and 2,381 women) enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study at baseline (1985-1986) and followed over 25 years (2010-2011). Longitudinal random effects linear regression models were used to test whether changes in drinking (defined categorically) as starting to drink, increasing, decreasing, stable drinking or stopping drinking (versus stable non-drinking) over a series of 5-yr periods were associated with corresponding 5-yr WC and BMI changes. Associations with 5-yr changes (defined categorically as starting, stable or stopping) in drinking level (i.e., light/moderate and excessive) and 5-yr changes (defined categorically as increasing, no change, or decreasing) by beverage type (i.e., beer, wine and liquor/mixed drinks) were also examined.
In men, compared to stable non-drinking, decreasing total alcohol intake was associated with lower 5-yr WC (β:-0.62 cm; 95% CI: -1.09, -0.14 cm) and BMI gains (β:-0.20 kg/m2; 95% CI: -0.30, -0.03 kg/m2) and stopping excessive drinking was associated with lower 5-yr WC gains (β:-0.77 cm; 95% CI: -1.51, -0.03 cm). In women, compared to those with stable non-drinking habits, starting light/moderate drinking was associated with lower 5-yr WC (β: -0.78 cm; 95% CI: -1.29, -0.26 cm) and BMI gains (β:-0.42 kg/m2; 95% CI: -0.64, -0.20 kg/m2). Increasing wine intake was associated with a lower 5-yr BMI gain (β:-0.27 kg/m2; 95% CI: -0.51, -0.03 kg/m2). Decreasing liquor/mixed drink (β:-0.33 kg/m2; 95% CI: -0.56, -0.09 kg/m2) intake was associated with lower 5-yr WC (β:-0.88 cm; 95% CI: -1.43, -0.34 cm) and BMI (β:-0.33 kg/m2; 95% CI: -0.56, -0.09 kg/m2) gains.
Associations of alcohol intake with obesity measures are complex. In women, wine and liquor/mixed drink intakes had contrasting associations with WC and BMI change. In men, decreasing weekly alcoholic beverage intake with an emphasis on stopping excessive consumption may be beneficial in managing WC and BMI gains.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background: Breakfast is associated with lower body weight in observational studies. Public health authorities commonly recommend breakfast consumption to reduce obesity, but the effectiveness of ...adopting these recommendations for reducing body weight is unknown.Objective: We tested the relative effectiveness of a recommendation to eat or skip breakfast on weight loss in adults trying to lose weight in a free-living setting. Design: We conducted a multisite, 16-wk, 3-parallel-arm randomized controlled trial in otherwise healthy overweight and obese adults body mass index (in kg/m2) between 25 and 40 aged 20–65 y. Our primary outcome was weight change. We compared weight change in a control group with weight loss in experimental groups told to eat breakfast or to skip breakfast no breakfast (NB). Randomization was stratified by prerandomization breakfast eating habits. A total of 309 participants were randomly assigned.Results: A total of 283 of the 309 participants who were randomly assigned completed the intervention. Treatment assignment did not have a significant effect on weight loss, and there was no interaction between initial breakfast eating status and treatment. Among skippers, mean (±SD) baseline weight-, age-, sex-, site-, and race-adjusted weight changes were −0.71 ± 1.16, −0.76 ± 1.26, and −0.61 ± 1.18 kg for the control, breakfast, and NB groups, respectively. Among breakfast consumers, mean (±SD) baseline weight-, age-, sex-, site-, and race-adjusted weight changes were −0.53 ± 1.16, −0.59 ± 1.06, and −0.71 ± 1.17 kg for the control, breakfast, and NB groups, respectively. Self-reported compliance with the recommendation was 93.6% for the breakfast group and 92.4% for the NB group.Conclusions: A recommendation to eat or skip breakfast for weight loss was effective at changing self-reported breakfast eating habits, but contrary to widely espoused views this had no discernable effect on weight loss in free-living adults who were attempting to lose weight. This trial was registered at clinicaltrails.gov as NCT01781780.
Previous studies have shown mixed results on the association between carbohydrate intake and insomnia. However, any influence that refined carbohydrates have on risk of insomnia is likely ...commensurate with their relative contribution to the overall diet, so studies are needed that measure overall dietary glycemic index (GI), glycemic load, and intakes of specific types of carbohydrates.
We hypothesized that higher GI and glycemic load would be associated with greater odds of insomnia prevalence and incidence.
This was a prospective cohort study with postmenopausal women who participated in the Women’s Health Initiative Observational Study, investigating the relations of GI, glycemic load, other carbohydrate measures (added sugars, starch, total carbohydrate), dietary fiber, and specific carbohydrate-containing foods (whole grains, nonwhole/refined grains, nonjuice fruits, vegetables, dairy products) with odds of insomnia at baseline (between 1994 and 1998; n = 77,860) and after 3 y of follow-up (between 1997 and 2001; n = 53,069).
In cross-sectional and longitudinal analyses, higher dietary GI was associated with increasing odds of prevalent (fifth compared with first quintile OR: 1.11; CI: 1.05, 1.16; P-trend = 0.0014) and incident (fifth compared with first quintile OR: 1.16; CI: 1.08, 1.25; P-trend < 0.0001) insomnia in fully adjusted models. Higher intakes of dietary added sugars, starch, and nonwhole/refined grains were each associated with higher odds of incident insomnia. By contrast, higher nonjuice fruit and vegetable intakes were significantly associated with lower odds of incident insomnia. Also, higher intakes of dietary fiber, whole grains, nonjuice fruit, and vegetables were significantly associated with lower odds of prevalent insomnia.
The results suggest that high-GI diets could be a risk factor for insomnia in postmenopausal women. Substitution of high-GI foods with minimally processed, whole, fiber-rich carbohydrates should be evaluated as potential treatments of, and primary preventive measures for, insomnia in postmenopausal women.
Purpose
Although laboratory studies suggest a potential role of magnesium (Mg) in weight regulation, human studies relating Mg intake to body weight are limited. This study sought to prospectively ...examine the association between Mg intake and incidence of obesity and related anthropometric and biochemical indicators.
Methods
The Coronary Artery Risk Development in Young Adults (CARDIA) study recruited 5115 American young adults, aged 18–30 years, at baseline in 1985–6, and re-examined them in eight follow-ups. Incident obesity was defined as body mass index (BMI) ≥ 30 kg/m
2
. Dietary Mg intake was collected using the CARDIA Diet History at baseline and exam years 7 and 20.
Results
During the 30-year follow-up, 1675 incident cases of obesity were identified. After adjustment for potential confounders, Mg intake was inversely associated with incidence of obesity. The multivariable-adjusted hazard ratios (95% confidence interval) from quintile 1 (Q1) (lowest intake group) to quintile 5 (Q5) (highest intake group) were 1 (referent), 0.86 (0.74, 1.00), 0.83 (0.71, 0.97), 0.55 (0.46, 0.66), and 0.49 (0.40, 0.60);
P
for trend < 0.01. Consistently, Mg intake was inversely associated with the levels of BMI, triceps skinfold, suprailiac skinfold, subscapular skinfold, fasting insulin, and C-reactive protein. The observed associations were not materially modified by age, sex, race, or BMI at baseline. In addition, the intakes of foods rich in Mg, including whole grains, nuts and seeds, legumes, and dark-green vegetables, were associated with lower incidence of obesity.
Conclusions
This longitudinal study suggests that Mg intake is inversely associated with incidence of obesity.
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