Small Interfering RNAs (siRNAs) Negatively Impact Growth and Gene Expression of Environmentally Relevant Bacteria in In Vitro Conditions.

Rising global populations have amplified food scarcity and ushered in the development of genetically modified (GM) crops containing small interference RNAs (siRNAs) that control gene expression to overcome these challenges. The use of RNA interference (RNAi) in agriculture remains controversial due to uncertainty regarding the unintended release of genetic material and downstream nontarget effects, which have not been assessed in environmental bacteria to date. To evaluate the impacts of siRNAs used in agriculture on environmental bacteria, this study assessed microbial growth and viability as well as transcription activity with and without the presence of environmental stressors. Results showed a statistically significant reduction in growth capacity and maximum biomass achieved when bacteria are exposed to siRNAs alone and with additional external stress (p < 0.05). Further transcriptomic analysis demonstrated that nutrient cycling gene activities were found to be consistently and significantly altered following siRNA exposure, particularly among carbon (xylA, FBPase, limEH, Chitinase, rgl, rgh, rgaE, mannanase, ara) and nitrogen (ureC, nasA, narB, narG, nirK) cycling genes (p < 0.05). Decreases in carbon cycling gene transcription profiles were generally significantly enhanced when siRNA exposure was coupled with nutrient or antimicrobial stress. Collectively, findings suggest that certain conditions facilitate the uptake of siRNAs from their surrounding environments that can negatively affect bacterial growth and gene expression activity, with uncertain downstream impacts on ecosystem homeostasis.

Evaluating the impacts of triclosan on wastewater treatment performance during startup and acclimation.

Triclosan (TCS) is a broad range antimicrobial agent used in many personal care products, which is commonly discharged to wastewater treatment facilities (WWTFs). This study examined the impact of TCS on wastewater treatment performance using laboratory bench-scale sequencing batch reactors (SBRs) coupled with anaerobic digesters. The SBRs were continuously fed synthetic wastewater amended with or without 0.68 µM TCS, with the aim of determining the effect of chronic TCS exposure as opposed to a pulse TCS addition as previously studied. Overall, the present study suggests inhibition of nitrogen removal during reactor startup. However, NH4+ removal fully rebounded after 63 days, suggesting acclimation of the associated microbial communities to TCS. An initial decrease in microbial community diversity was observed in the SBRs fed TCS as compared to the control SBRs, followed by an increase in community diversity, which coincided with the increase in NH4+ removal. Elevated levels of NO3- and NO2- were found in the reactor effluent after day 58, however, suggesting ammonia oxidizing bacteria rebounding more rapidly than nitrogen oxidizing bacteria. Similar effects on treatment efficiencies at actual WWTFs have not been widely observed, suggesting that continuous addition of TCS in their influent may have selected for TCS-resistant nitrogen oxidizing bacteria.

Genetic and environmental influences on last-year major depression in adulthood: a highly heritable stable liability but strong environmental effects on 1-year prevalence.

BACKGROUND: This study seeks to clarify the contribution of temporally stable and occasion-specific genetic and environmental influences on risk for major depression (MD). METHOD: Our sample was 2153 members of female-female twin pairs from the Virginia Twin Registry. We examined four personal interview waves conducted over an 8-year period with MD in the last year defined by DSM-IV criteria. We fitted a structural equation model to the data using classic Mx. The model included genetic and environmental risk factors for a latent, stable vulnerability to MD and for episodes in each of the four waves. RESULTS: The best-fit model was simple and included genetic and unique environmental influences on the latent liability to MD and unique wave-specific environmental effects. The path from latent liability to MD in the last year was constant over time, moderate in magnitude (+0.65) and weaker than the impact of occasion-specific environmental effects (+0.76). Heritability of the latent stable liability to MD was much higher (78%) than that estimated for last-year MD (32%). Of the total unique environmental influences on MD, 13% reflected enduring consequences of earlier environmental insults, 17% diagnostic error and 70% wave-specific short-lived environmental stressors. CONCLUSIONS: Both genetic influences on MD and MD heritability are stable over middle adulthood. However, the largest influence on last-year MD is short-lived environmental effects. As predicted by genetic theory, the heritability of MD is increased substantially by measurement at multiple time points largely through the reduction of the effects of measurement error and short-term environmental risk factors.

Depressive vulnerability, stressful life events and episode onset of major depression: a longitudinal model.

BACKGROUND: The nature of the relationship between depressive vulnerability (DV) and acute adversity in the etiology of major depression (MD) remains poorly understood. METHOD: Stressful life events (SLEs) and MD onsets in the last year were assessed at four waves in cohort 1 (females) and at two waves in cohort 2 (males and females) from the Virginia Adult Twin Study. Structural equation modeling was conducted in Mplus. RESULTS: In cohort 1, DV was strongly indexed by depressive episodes over the four waves (paths from +0.72 to 0.79) and predicted by SLEs in the month of their occurrence (+0.31 to 0.36). Wave-specific DV was associated both with stable DV (+0.29 to 0.33) and by forward transmission of DV from the preceding wave (+0.33 to 0.36). SLEs were predicted by stable DV (+0.29) and from SLEs in the preceding month (+0.06). As the cohort aged, MD onsets were better indexed by DV and more poorly predicted by SLEs. Parameter estimates were similar in males and females from cohort 2. In individuals with prior depressive episodes, the association between MD onset and SLEs was weakened while the prediction of SLEs from DV was substantially strengthened. We found no evidence for 'reverse causation' from MD episodes to SLEs. CONCLUSION: The interrelationship between DV and acute adversity in the etiology of MD is complex and temporally dynamic. DV impacts on MD risk both directly and indirectly through selection into high stress environments. Over time, depressive episodes become more autonomous. Both DV and SLEs transmit forward over time and therefore form clear targets for intervention.

A prospective longitudinal model predicting early adult alcohol problems: evidence for a robust externalizing pathway.

BACKGROUND: Risk factors for alcohol problems (AP) include biological and environmental factors that are relevant across development. The pathways through which these factors are related, and how they lead to AP, are optimally considered in the context of a comprehensive developmental model. METHOD: Using data from a prospectively assessed, population-based UK cohort, we constructed a structural equation model that integrated risk factors reflecting individual, family and peer/community-level constructs across childhood, adolescence and young adulthood. These variables were used to predict AP at the age of 20 years. RESULTS: The final model explained over 30% of the variance in liability to age 20 years AP. Most prominent in the model was an externalizing pathway to AP, with conduct problems, sensation seeking, AP at age 17.5 years and illicit substance use acting as robust predictors. In conjunction with these individual-level risk factors, familial AP, peer relationships and low parental monitoring also predicted AP. Internalizing problems were less consistently associated with AP. Some risk factors previously identified were not associated with AP in the context of this comprehensive model. CONCLUSIONS: The etiology of young adult AP is complex, influenced by risk factors that manifest across development. The most prominent pathway to AP is via externalizing and related behaviors. These findings underscore the importance of jointly assessing both biologically influenced and environmental risk factors for AP in a developmental context.

Perceptions of European medical staff on the facilitators and barriers to physical closeness between parents and infants in neonatal units.

AIM: Studies have provided insights into factors that may facilitate or inhibit parent-infant closeness in neonatal units, but none have specifically focused on the perspectives of senior neonatal staff. The aim of this study was to explore perceptions and experiences of consultant neonatologists and senior nurses in five European countries with regard to these issues. METHODS: Six small group discussions and three-one-to-one interviews were conducted with 16 consultant neonatologists and senior nurses representing nine neonatal units from Estonia, Finland, Norway, Spain and Sweden. The interviews explored facilitators and barriers to parent-infant closeness and implications for policy and practice, and thematic analysis was undertaken. RESULTS: Participants highlighted how a humanising care agenda that enabled parent-infant closeness was an aspiration, but pointed out that neonatal units were at different stages in achieving this. The facilitators and barriers to physical closeness included socio-economic factors, cultural norms, the designs of neonatal units, resource issues, leadership, staff attitudes and practices and relationships between staff and parents. CONCLUSION: Various factors affected parent-infant closeness in neonatal units in European countries. There needs to be the political motivation, appropriate policy planning, legislation and resource allocation to increase measures that support closeness agendas in neonatal units.

Differential parenting and risk for psychopathology: a monozygotic twin difference approach.

PURPOSE: Consistent and non-specific associations have been found between parenting style and major depression, anxiety disorders, and externalizing behavior. Although often considered part of twins' shared environment, parenting can also be conceptualized as non-shared environment. Non-shared environmental influences have important effects on development but are difficult to test and sort out because of the possible confounding effects of gene-environment interactions and evocative gene-environment correlations. The monozygotic (MZ) differences approach is one way to analytically investigate non-shared environment. METHODS: The aim of the present study is to use the MZ differences approach to investigate the relationship between differential parenting among 1303 twin pairs (mean age 36.69 ± 8.56) and differences in total symptom counts of major depression (MD), generalized anxiety disorder (GAD), conduct disorder (CD), and anti-social behavior (ASB) during adulthood. RESULTS: Although effect sizes tended to be small, a number of results were significantly different from zero. Perceived differences in parental coldness was positively associated with internalizing disorders. Differences in protectiveness were negatively associated with MD, GAD, and ASB. Differences in authoritarianism were positively associated with MD and CD, but negatively associated with ASB. CONCLUSIONS: Perceived differences in parenting style are associated with differences in MD, GAD, CD, and ASB outcomes in a sample of MZ twins. Despite the lack of a basis for making causal inferences about parenting style and psychopathology, these results are suggestive of such a relationship and show that non-shared environmental influence of parenting does in some cases significantly predict adult psychopathology.

Genetic and environmental risk factors in males for self-report externalizing traits in mid-adolescence and criminal behavior through young adulthood.

BACKGROUND: Externalizing traits or behaviors are typically assessed by self-report scales or criminal records. Few genetically informative studies have used both methods to determine whether they assess the same genetic or environmental risk factors. METHOD: We examined 442 male Swedish twin pairs with self-reported externalizing behaviors at age 16­17 years [externalizing traits (EXT), self-reported delinquency (SRD), impulsivity (IMP), grandiosity (GRD) and callousness (CLS)] and criminal behavior (CB) from the National Suspect Registry from age 13 to 25 years. Multivariate structural equation modeling was conducted with Mx. RESULTS: The best-fit model contained one genetic, one shared environmental and two non-shared environmental common factors, and variable specific genetic and non-shared environmental factors. The risk for CB was influenced substantially by both genetic (a2=0.48) and familial­environmental factors (c2=0.22). About one-third of the genetic risk for CB but all of the shared environmental risk was indexed by the self-report measures. The degree to which the individual measures reflected genetic versus familial­environmental risks for CB varied widely. GRD and CLS were correlated with CB mainly through common genetic risk factors. SRD and CB covaried largely because of shared familial­environmental factors. For EXT and IMP, observed correlations with CB resulted in about equal parts from shared genetic and shared familial­environmental factors. CONCLUSIONS: In adolescence, measures of grandiose and callous temperament best tap the genetic liability to CB.Measures of antisocial behaviors better index familial­environmental risks for CB. A substantial proportion of the genetic risk to CB was not well reflected in any of the self-report measures.

Genetic innovation and stability in externalizing problem behavior across development: a multi-informant twin study.

The use of cross-informant ratings in previous longitudinal studies on externalizing behavior may have obscured the presence of continuity of genetic risk. The current study included latent factors representing the latent estimates of externalizing behavior based on both parent and self-report which eliminated rater-specific effects from these latent estimates. Symptoms of externalizing behavior of 1,480 Swedish twin pairs were obtained at ages 8-9, 13-14, 16-17 and 19-20 both by parent and self-report. Mx modeling was used to estimate additive genetic, shared and specific environmental influences. Genetic continuity was found over the entire developmental period as well as additional sources of genetic influence emerging around early and late adolescence. New unique environmental effects (E) on externalizing behavior arose early in adolescence. The results support both the presence of genetic continuity and change in externalizing behavior during adolescence due to newly emerging genetic and environmental risk factors.

Adherence to a low-fat vs. low-carbohydrate diet differs by insulin resistance status.

Previous research shows diminished weight loss success in insulin-resistant (IR) women assigned to a low-fat (LF) diet compared to those assigned to a low-carbohydrate (LC) diet. These secondary analyses examined the relationship between insulin-resistance status and dietary adherence to either a LF-diet or LC-diet among 81 free-living, overweight/obese women [age = 41.9 ± 5.7 years; body mass index (BMI) = 32.6 ± 3.6 kg/m(2)]. This study found differential adherence by insulin-resistance status only to a LF-diet, not a LC-diet. IR participants were less likely to adhere and lose weight on a LF-diet compared to insulin-sensitive (IS) participants assigned to the same diet. There were no significant differences between IR and IS participants assigned to LC-diet in relative adherence or weight loss. These results suggest that insulin resistance status may affect dietary adherence to weight loss diets, resulting in higher recidivism and diminished weight loss success of IR participants advised to follow LF-diets for weight loss.

Effect of fish oil supplementation on serum triglycerides, LDL cholesterol and LDL subfractions in hypertriglyceridemic adults.

BACKGROUND AND AIMS: The well-established triglyceride (TG) lowering effect of fish oil is accompanied by an increase in LDL-cholesterol (LDL-C) concentration. Less is known about the differential impact on LDL particle distribution - the smaller particles being associated with a greater risk for atherosclerosis. We aimed to examine the changes in serum concentrations of four subclasses of LDL particles as well as shifts in LDL phenotype patterns (A, B, AB) among hypertriglyceridemic adults. METHODS AND RESULTS: This was a secondary analysis from a double-blind, parallel design, placebo controlled trial with 42 adults that experienced significant TG lowering and modest increases in total LDL-C concentrations after 12 weeks of 4 g/d EPA + DHA. Reduction in serum TG concentrations (mean ± SEM) was -26 ± 4% (-0.81 ± 10.12 mmol/L), p < 0.0001. Total LDL-C concentration increased by 13 ± 3% (+0.31 ± 0.08 mmol/L), p < 0.0001. The 12-week changes in concentrations of LDL1, LDL2, LDL3 and LDL4 were +0.06 ± 0.02 mmol/L [+2.2 ± 0.7 mg/dL], +0.07 ± 0.03 mmol/L [+2.6 ± 1.0 mg/dL], +0.16 ± 0.05 mmol/L [+6.3 ± 1.8 mg/dL], and +0.04 ± 0.04 mmol/L [+1.4 ± 1.7 mg/dL], respectively (+20 ± 5%, +64 ± 13%, +26 ± 6%, and +17 ± 9%), p < 0.05 for all but LDL4. Changes in LDL phenotype patterns A, B and A/B were negligible and not statistically significant. CONCLUSION: In this population of hypertriglyceridemic adults, dietary supplementation with fish oil resulted in an increase in total LDL-C concentration which was distributed relatively evenly across the range of smaller and more atherogenic as well as larger and less atherogenic LDL particles.

Difficult airway communication between anaesthetists and general practitioners.

BACKGROUND AND AIMS: Advance warning of patients who are difficult to intubate may prevent an airway catastrophe but relies on effective communication between specialties. Anaesthetists aim to inform general practitioners whenever a difficult airway is encountered and expect general practitioners to include this information in subsequent referrals. We investigated how anaesthetists communicated with general practitioners, their knowledge of the Read Code (used by general practitioner computer systems) for difficult tracheal intubation, and how likely general practitioners were to pass the information on. METHODS AND RESULTS: We surveyed 631 consultant anaesthetists and 217 general practitioners. We found only 125 (20%) anaesthetists consistently wrote difficult airway letters to general practitioners. Only 20 (3%) knew the Read Code for difficult intubation (SP2y3), although 454 (72%) thought it to be useful. Most general practitioners (212, 98%) thought airway information to be important, but only half receiving a difficult airway communication forwarded it on. General practitioners recommended including the Read Code SP2y3 and labelling it 'high priority', ensuring that 'Difficult Tracheal Intubation' would be listed in the Emergency Care Summary generated for hospital referrals. CONCLUSION: Communication between anaesthetists and general practitioners is currently poor, but could be improved by simplifying difficult airway letters and including the SP2y3 code and a statement of priority.

Improving covalent cell encapsulation with temporarily reactive polyelectrolytes.

Calcium alginate/poly-L-lysine beads were coated with either 50% hydrolyzed poly(methyl vinyl ether-alt-maleic anhydride) (PMM(50)), or with poly(vinyl dimethyl azlactone-co-methacrylic acid) (50:50, PMV(50)), to form covalently shell-crosslinked capsules, and compared with analogous capsules coated with sodium alginate. All capsule types were prepared with and without C2C12 murine myoblast cells, and implanted into mice for up to 6 weeks. Cell viability, capsule integrity, fibrotic overgrowth, and mechanical strength of the capsules were assessed, and correlated with inflammatory cytokine marker levels in tail vein blood samples taken at different time points. AP-PMM(50) capsules displayed the least amount of fibrotic overgrowth, were found to be the strongest, and showed the lowest levels of TNF-α in tail vein serum samples taken at 4 h, 24 h, 1 and 6 weeks post transplantation. The results for APA and AP-PMV(50) capsules were more variable and depended on the presence or absence of encapsulated cells.

Predicting alcohol consumption in adolescence from alcohol-specific and general externalizing genetic risk factors, key environmental exposures and their interaction.

BACKGROUND: Alcohol consumption is influenced by specific genetic risk factors for alcohol use disorders (AUDs), non-specific genetic risk factors for externalizing behaviors and various environmental experiences. We have limited knowledge of how these risk factors inter-relate through development. METHOD: Retrospective assessments in 1796 adult male twins using a life history calendar of key environmental exposures and alcohol consumption from early adolescence to mid-adulthood. Analysis by linear mixed models. RESULTS: The importance of non-specific genetic risk factors on maximal alcohol consumption rose rapidly in early to mid-adolescence, peaked at ages 15-17 years and then declined slowly. Alcohol-specific genetic risk factors increased slowly in influence through mid-adulthood. We detected robust evidence for environmental moderation of genetic effects on alcohol consumption that was more pronounced in early and mid-adolescence than in later periods. Alcohol availability, peer deviance and low prosocial behaviors showing the strongest moderation effects. More interactions with environmental risk factors were seen for the non-specific externalizing disorder risk than for specific genetic risk for AUDs. CONCLUSIONS: The impact of specific and non-specific genetic influences on alcohol consumption have different development trajectories. Genetic effects on alcohol use are more pronounced when social constraints are minimized (e.g. low prosocial behaviors or parental monitoring) or when the environment permits easy access to alcohol and/or encourages its use (e.g. high alcohol availability or peer deviance). Gene-environment interactions influencing alcohol intake may be more robust at younger ages, indicating greater plasticity of genetic influences early in the development of drinking patterns.

A longitudinal etiologic model for symptoms of anxiety and depression in women.

BACKGROUND: Designed as state measures to monitor treatment response, symptoms of anxiety and depression (SxAnxDep) also have trait-like characteristics. No comprehensive etiologic model for SxAnxDep has illuminated the inter-relationship between their state- and trait-like characteristics, while including key predictor variables. METHOD: In a prospective three-wave study of 2395 female twins from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders (VATSPSUD), we examined, using structural equation modeling, how genes, childhood and past-year environmental stressors, personality and episodes of major depression (MD) and generalized anxiety disorder (GAD) influence SxAnxDep. RESULTS: The best-fit model, which explained 68-74% of the variance in SxAnxDep, revealed two etiologic pathways. Stable levels of SxAnxDep resulted largely from neuroticism, which in turn was influenced by genetic and early environment risk factors. Occasion-specific influences resulted from stressful events mediated through episodes of MD or GAD. These two pathways, which had approximately equal influences on levels of SxAnxDep, were substantially correlated because the genetic, early environmental and personality factors that impacted on stable symptom levels also predisposed to event exposure and disorder onset. No significant interaction was seen between the two pathways. CONCLUSIONS: SxAnxDep in women in the general population arise from two inter-related causal pathways. The first, the 'trait-like' pathway, reflects genetic and early environmental risk factors, and is mediated largely through personality. The second pathway is mediated through episodes of MD and GAD, and is the result of both recent environmental adversities and trait-like factors that influence event exposure and the probability of disorder onset.

Hypopituitarism--a late consequence of aneurysmal subarachnoid haemorrhage?

Over the last decade subarachnoid haemorrhage (SAH) has increasingly been recognised as a cause of hypopituitarism. We report on the case of a patient with evidence of growth hormone deficiency manifesting after a period of time, with a favourable response to growth hormone replacement. This is followed by a review of the current literature.

Dietary assessment can be based on pattern recognition rather than recall.

Diet is the leading predictor of health status, including all-cause mortality, in the modern world, yet is rarely measured; whereas virtually every adult in a developed country knows their approximate blood pressure, hardly any knows their objective diet quality. Leading authorities have called for the inclusion of nutrition in every electronic health record as one of the many remedial steps required to give dietary quality the routine attention it warrants. Existing tools to capture dietary intake are based on either real-time journaling or recall. Journaling, or logging, is time and labor intensive. Recall is notoriously unreliable, as humans are notably bad at remembering detail. Even allowing for the challenge of recall, these dietary intake methods are labor and time intensive, and require analysis at the n-of-1 level. We hypothesize that dietary intake assessment can be "reverse engineered"-predicating assessment on the recognition of fully formed dietary patterns-rather than endeavoring to assemble such a representation one food, meal, dish, or day at a time. This pattern recognition-based method offers potential advantages over existing methods, including speed, efficiency, cost, and applicability. We have developed and provisionally tested such a system, and the results thus far support our hypothesis. We are convinced that leveraging pattern recognition to make dietary assessment quick, user-friendly, economical, and scalable can allow for the conversion of dietary quality into a universally measured and routinely managed vital sign. In this paper, we present the supporting case.

Lidar observations of the meteoric deposition of mesospheric metals.

The mesospheric sodium and iron layers at an altitude between about 80 and 110 kilometers are routinely monitored by atmospheric physicists using resonance fluorescence lidar techniques because these constituents are excellent tracers of mesopause chemistry and dynamics. The mesospheric metals are the products of meteoric ablation. Existing ablation profiles are model calculations based in part on radar observations of the ionized background atmosphere left in the wake of high-speed (> 20 kilometers per second) meteoroids. Thin trails of neutral metal atoms, ablated from individual meteoroids, are occasionally observed with high-power lidars. The vertical distribution of 101 sodium and 5 iron meteor trails observed during the past 4 years at Urbana, Illinois; Arecibo, Puerto Rico; and near Hawaii is approximately Gaussian in shape with a centroid height of 89.0 (+/- 0.3) kilometers and a root-mean-square width of 3.3 (+/- 0.2) kilometers. This directly measured ablation profile is nearly the same as the mean iron layer profile but is considerably different from existing models and the distribution of ionized meteor trails observed by radars. A lower limit on the influx to the mesopause region from the lidar meteors is approximately 1.6 x 10(3) sodium and 2.7 x 10(4) iron atoms per second per square centimeter, which corresponds to an annual flux of meteoric debris into the mesosphere of about 2.0 (+/-0.6) gigagrams. Because the lidars can detect only the ablation trails left by the larger meteors, the observations suggest that the actual meteoric influx may be larger than the more recently reported values, which range between 16 and 78 gigagrams per year.

Dietary adherence and weight loss success among overweight women: results from the A TO Z weight loss study.

BACKGROUND: Dietary adherence has been implicated as an important factor in the success of dieting strategies; however, studies assessing and investigating its association with weight loss success are scarce. OBJECTIVE: We aimed to document the level of dietary adherence using measured diet data and to examine its association with weight loss success. DESIGN: Secondary analysis was performed using data from 181 free-living overweight/obese women (mean+/-s.d. age=43+/-5 years, body mass index=31+/-4 kg m(-2)) participating in a 1-year randomized clinical trial (the A TO Z study) comparing popular weight loss diets (Atkins, Zone and Ornish). Participants' dietary adherence was assessed as the difference between their respective assigned diet's recommended macronutrient goals and their self-reported intake. Association between dietary adherence and 12-month weight change was computed using Spearman's correlations. Differences in baseline characteristics and macronutrient intake between the most and least adherent tertiles for diet groups were compared using t-tests. RESULTS: Within each diet group, adherence score was significantly correlated with 12-month weight change (Atkins, r(s)=0.42, P=0.0003; Zone, r(s)=0.34, P=0.009 and Ornish, r(s)=0.38, P=0.004). Twelve-month weight change in the most vs least adherent tertiles, respectively, was -8.3+/-5.6 vs -1.9+/-5.8 kg, P=0.0006 (Atkins); -3.7+/-6.3 vs -0.4+/-6.8 kg, P=0.12 (Zone) and -6.5+/-6.8 vs -1.7+/-7.9 kg, P=0.06 (Ornish). CONCLUSIONS: Regardless of assigned diet groups, 12-month weight change was greater in the most adherent compared to the least adherent tertiles. These results suggest that strategies to increase adherence may deserve more emphasis than the specific macronutrient composition of the weight loss diet itself in supporting successful weight loss.

Pathways and mechanisms linking dietary components to cardiometabolic disease: thinking beyond calories.

Calories from any food have the potential to increase risk for obesity and cardiometabolic disease because all calories can directly contribute to positive energy balance and fat gain. However, various dietary components or patterns may promote obesity and cardiometabolic disease by additional mechanisms that are not mediated solely by caloric content. Researchers explored this topic at the 2017 CrossFit Foundation Academic Conference 'Diet and Cardiometabolic Health - Beyond Calories', and this paper summarizes the presentations and follow-up discussions. Regarding the health effects of dietary fat, sugar and non-nutritive sweeteners, it is concluded that food-specific saturated fatty acids and sugar-sweetened beverages promote cardiometabolic diseases by mechanisms that are additional to their contribution of calories to positive energy balance and that aspartame does not promote weight gain. The challenges involved in conducting and interpreting clinical nutritional research, which preclude more extensive conclusions, are detailed. Emerging research is presented exploring the possibility that responses to certain dietary components/patterns are influenced by the metabolic status, developmental period or genotype of the individual; by the responsiveness of brain regions associated with reward to food cues; or by the microbiome. More research regarding these potential 'beyond calories' mechanisms may lead to new strategies for attenuating the obesity crisis.