Comparison of dietary intakes in four selected European populations

Summary The composition of diet and food intakes in four selected European populations were compared. Dietary data (from the World Health Organization Project on Monitoring Trends and Determinants in Cardiovascular Disease) were measured by record methods and were available for middle-aged men in Finland (n = 653), France (n =1128), Northern Ireland (n = 356), and southern Germany (Augsburg region; n = 899). Nutritional variables — which are independent of the absolute energy intake, such as the percentage supply of energy from macronutrients and the ratio of polyunsaturated to saturated fatty acids — were on the whole similar. However, striking differences were found in food intake and in the percentage supply of fat from different foods. The results indicate that detailed knowledge of consumption figures is necessary to develop prudent and acceptable nutrition intervention programs.Abbreviations CHD coronary heart disease - MONICA monitoring trends and determinants in cardiovascular disease - MUFA monounsaturated fatty acids - P/S ratio ratio of polyunsaturated fatty acids/saturated fatty acids - PUFA polyunsaturated fatty acids - SFA saturated fatty acids     

Flavor preferences,food intake,and weight gain in baboons (Papio sp.)

To evaluate the influence of flavor on ad lib consumption and on associated changes in body weight, female baboons, 7–15 years of age, served in two experiments with seven monkey chows which were identical except for flavor: lemon, orange, apple, sugar, fruit punch, chocolate, and unflavored. In the first experiment, two groups of animals (n=7 and 4) received five of the seven flavors, presented in daily pair-wise combinations. Analysis of quantities consumed demonstrated marked and consistent flavor preferences in individual baboons. Although specific preference varied between animals, total amounts consumed of the various flavors differed significantly, with rank ordering clearly evident. Overall food intake and body weights increased significantly over baseline values obtained with a standard, unflavored chow. In the second experiment, three baboons received chow of a preferred flavor for nine weeks. Amounts consumed and body weights increased significantly over baseline. These results indicate that flavored chows may be useful for producing a nonhuman primate behavioral model of obesity and for inducing animals to eat otherwise unpalatable diets.     

Post-exercise ketosis and the glycogen content of liver and muscle in rats on a high carbohydrate diet

Summary Post-exercise ketosis is known to be suppressed by physical training and by a high carbohydrate diet. As a result it has often been presumed, but not proven, that the development of post-exercise ketosis is closely related to the glycogen content of the liver. We therefore studied the effect of 1 h of treadmill running on the blood 3-hydroxybutyrate and liver and muscle glycogen concentrations of carbohydrate-loaded trained (n=72) and untrained rats (n=72). Resting liver and muscle glycogen levels were 25%–30% higher in the trained than in the untrained animals. The resting 3-hydroxybutyrate concentrations of both groups of rats were very low: <0.08 mmol·1⁻¹. Exercise did not significantly influence the blood 3-hydroxybutyrate concentrations of trained rats, but caused a marked post-exercise ketosis (1.40±0.40 mmol·1⁻¹ 1 h after exercise) in the untrained animals, the time-course of which was the approximate inverse of the changes in liver glycogen concentration. Interpreting the results in the light of similar data obtained after a normal and low carbohydrate diet it has been concluded that trained animals probably owe their relative resistance to post-exercise ketosis to their higher liver glycogen concentrations as well as to greater peripheral stores of mobilizable carbohydrate.     

Self-selecting albino rats exhibit differential preferences for pure macronutrient diets: Characterization of three subpopulations

Analyses of natural feeding behavior in albino male Sprague-Dawley rats demonstrate that, when allowed to self-select from pure macronutrient diets (protein, carbohydrate and fat), these rats of the same genetic strain can be categorized into 3 subpopulations according to either their 24-h or their 12-h nocturnal patterns of nutrient intake. A majority of the animals (HC for high carbohydrate, 50% of the total population) consumed a diet rich in carbohydrate relative to protein or fat, while a smaller population of rats (HF, 30%) preferred the fat diet, and an even smaller population (HP, 20%) chose a high-protein diet. These 3 subpopulations, after a few weeks of maintenance on the diets, differed in their body weight, with the HF rats having a higher body weight than the HP animals, who tended to weigh more than the lightest HC rats. Whereas all subgroups exhibited a similar bimodal distribution of feeding during the nocturnal cycle, with peaks during the early and late dark periods, they were distinguishable on the basis of their nutrient consumption during specific phases of the dark cycle. This difference was most apparent in the early dark phase, when the 3 subgroups exhibited exaggerated preferences for the specific nutrient that was generally preferred over the 24-h cycle. This is in contrast to the middle dark phase, when diet preferences were attenuated or lost, and the late dark phase, when most rats were similar in showing an increased preference for protein and fat and a decreased preference for carbohydrate. The HF group was further distinguished by an unusually strong burst of feeding during the first 2 h of the dark period and an extra peak of feeding in the middle dark period (7th h), both of which were relatively high in fat content.     

Diet selection and metabolic fuels in three models of diabetes mellitus

Dietary self-selection and circulating metabolic fuels (glucose, free fatty acids, ketones) were examined in three forms of experimental diabetes mellitus in rats: pancreatectomy and streptozotocin treatment in adult and neonatal rats. Changes in diet selection resulting from insulin replacement also were examined. Differences were found in diet selection and circulating metabolic fuels between these types of diabetes. Mildly diabetic rats selected large amounts of fat while more severely diabetic rats primarily selected protein. Insulin treatment enhanced carbohydrate intake of diabetic rats and nearly normalized diet selection and circulating metabolic fuels. All diabetic groups exhibited severe glucose intolerance. These results support the observations of the beneficial effects of low-carbohydrate diets, question the generality of the use of high-fat diets, and suggest a more important role for high-protein diets in energy regulation in severely diabetic rats.     

Long-term elevations of dietary sodium produce parallel increases in the renal excretion of urodilatin and sodium

The effects of dietary sodium intake on the renal excretion of urodilatin and of sodium were examined in six healthy male subjects. The 24-day study period was divided into three phases of 8 days each. Subjects Ingested 2.8 mequiv sodium (kg body weight)^–1 day^–1 during the first phase, 5.6 mequiv (kg body weight)^–1 day^–1 during the second phase, and 8.4 mequiv (kg body weight)^–1 day^–1 during the third phase. The excretion of both sodium (P<0.002) and urodilatin (P<0.006) increased in response to the increasing dietary sodium, while urine flow did not change. Urinary urodilatin excretion correlated closely with renal sodium excretion (P<0.001). Serum aldosterone levels (P<0.01) as well as serum renin levels (P<0.05) significantly decreased with increasing sodium intake. Plasma [Arg]vasopressin levels increased significantly (P<0.05). Plasma atrial natriuretic factor and cGMP levels as well as urinary cGMP excretion rates were unaltered by the changes in sodium intake. We conclude from these results that the renal natriuretic peptide, urodilatin, but not the main cardiac member of the natriuretic peptide family may be involved in the regulation of day-to-day sodium balance.     

Micropuncture studies on the filtration rate of single superficial and juxtamedullary glomeruli in the rat kidney

Summary Single nephron filtration rates of superficial and juxtamedullary nephrons were determined in high and low sodium rats. Single nephron GFR was calculated from TF/P inulin and tubular flow rate in superficial nephrons and single juxtamedullary GFR from corresponding data in long loops of Henle. In low sodium rats superficial nephron GFR was 23.5±6.4 (SD)×10^–6 ml/min×g KW, juxtamedullary nephron GFR was 58.2±13.6 and total kidney GFR (C _In) was 0.94±0.16 ml/min×g KW. Using these single nephron values, total kidney GFR and a total number of 30,000 glomeruli per kidney, the number of superficial and juxtamedullary glomeruli was calculated to be 23,267 and 6,733, respectively. During high sodium diet superficial nephron GFR increased to 38.1±11.3 and single juxtamedullary GFR decreased to 16.5±6.6, total kidney GFR increasing to 1.01±0.24. Calculation again revealed the same distribution of the two nephron types. End-proximal TF/P inulin in superficial nephrons was 2.36±0.36 in low sodium and 2.31±0.28 in high sodium rats. Loops of Henle TF/P inulin and intratubular flow rate were inversely related: the highest TF/P inulin values and lowest intratubular flow rates were found in the descending limb. These data quantify the distribution of superficial and juxtamedullary nephrons on a functional basis and suggest a mechanism by which the kidney adjusts sodium excretion by altering the contribution of each nephron type to total kidney GFR.Supported by the Deutsche Forschungsgemeinschaft and the U.S. Department of the Army, through its European Research Office.     

Associations of Dietary Patterns with Incident Depression: The Maastricht Study

Our aim was to assess the association between a priori defined dietary patterns and incident depressive symptoms. We used data from The Maastricht Study, a population-based cohort study (n = 2646, mean (SD) age 59.9 (8.0) years, 49.5% women; 15,188 person-years of follow-up). Level of adherence to the Dutch Healthy Diet (DHD), Mediterranean Diet, and Dietary Approaches To Stop Hypertension (DASH) were derived from a validated Food Frequency Questionnaire. Depressive symptoms were assessed at baseline and annually over seven-year-follow-up (using the 9-item Patient Health Questionnaire). We used Cox proportional hazards regression analyses to assess the association between dietary patterns and depressive symptoms. One standard deviation (SD) higher adherence in the DHD and DASH was associated with a lower hazard ratio (HR) of depressive symptoms with HRs (95%CI) of 0.78 (0.69–0.89) and 0.87 (0.77–0.98), respectively, after adjustment for sociodemographic and cardiovascular risk factors. After further adjustment for lifestyle factors, the HR per one SD higher DHD was 0.83 (0.73–0.96), whereas adherence to Mediterranean and DASH diets was not associated with incident depressive symptoms. Higher adherence to the DHD lowered risk of incident depressive symptoms. Adherence to healthy diet could be an effective non-pharmacological preventive measure to reduce the incidence of depression.     

Marginal,Low, and Very-Low Food Security among Children Are Associated with Intake of Select Dietary Factors during Summer

BackgroundSchool meals are associated with improved food security status and dietary intake. Children receiving free and reduced-price school meals lose access to these meals during the summer. The association between food security status and dietary intake in these children during summer is unclear.ObjectiveTo examine the association between food security status (high, marginal, low, and very-low food security) among children and intake of select dietary factors during summer in children certified for free and reduced-price school meals by age group (3 to 4 years, 5 to 8 years, 9 to 12 years, and 13 to 17 years).DesignCross-sectional analysis.Participants/settingSecondary data from 11,873 children aged 3 to 17 years in the control group of the US Department of Agriculture Summer Electronic Benefit Transfer for Children Demonstration Project.Main outcome measuresConsumption of total fruits and vegetables; fruits and vegetables, excluding fried potatoes; whole grains; added sugars; added sugars, excluding cereals; added sugars from sugar-sweetened beverages; and dairy products assessed using questions from the 2009-2010 National Health and Nutrition Examination Survey Multifactor Diet Screener.Statistical analysisMultiple linear regression.ResultsFor the majority of age groups, marginal food security, low food security, and very-low food security were associated with lower fruit and vegetable consumption and low food security and very-low food security were associated with lower dairy consumption, with children from households with very-low food security having the lowest consumption. Children from households with very-low food security consumed 0.73 (95% CI –0.93 to –0.53) to 0.99 (95% CI –1.59 to –0.39) cup equivalents less per day of fruits and vegetables and 0.49 (95% CI –0.65 to –0.34) to 0.68 (95% CI –1.07 to –0.29) cup equivalents less per day of dairy compared with children from households experiencing high food security.ConclusionsLower food security was associated with reduced consumption of fruits and vegetables and dairy products during summer in children from low-income households.     

The Diet Quality of a Sample of Predominantly Racial Minority Children From Low-Income Households Is Lower During the Summer vs School Year: Results From the Project Summer Weight and Environmental Assessment Trial Substudy

BackgroundLittle is known about the diet quality of racial minority children during the summertime when school is out of session and there is risk of accelerated weight gain. Project Summer Weight and Environmental Assessment Trial was an observational, prospective study exploring child weight status and health trends during the summer.ObjectiveThe objective of this substudy of Project Summer Weight and Environmental Assessment Trial was to examine the diet quality of elementary-aged racial minority children during the summertime vs school year.DesignThis observational, prospective substudy was conducted from June to September 2017.Participants/settingStudents in prekindergarten through fifth grade were recruited from 2 schools located in low-income urban neighborhoods of Columbus, OH, with a predominantly Black population. Sixty-two children (39 families) enrolled.Main outcome measuresTwenty-four-hour dietary recalls (2 weekdays, 1 weekend day) were collected at 3 time points: (1) beginning of summer (T0); (2) midsummer (T1); and (3) beginning of subsequent school year (T2). Healthy Eating Index (HEI)-2015 total and component scores were calculated to assess diet quality. Daily calories (kilocalories) and servings of types of foods within food groups were also assessed.Statistical analysesRepeated measures analysis of variance and Tukey’s post hoc analyses were performed.ResultsRetention was 76% (n = 47). Mean age was 7.0 ± 0.3 years, 79% (n = 37) were African American, and 58% of participants (n = 26) reported annual household incomes ≤$20,000. HEI-2015 total score was significantly lower during the summertime vs school year (P = .02). HEI-2015 component score for whole fruits (P = .04) was also lower in the summer vs school year, along with total vegetables (P < .001), greens and beans (P < .001) specifically, and legumes (P < .001). The HEI-2015 component score for added sugars (P = .04) was significantly lower in the summer vs the school year as well, indicating a higher intake of added sugars during the summer. On the other hand, whole grains were higher during the summer vs school year (P < .01), specifically snack chips (P = .03) and popcorn (P < .01). Total daily calories did not differ between the summertime vs school year.ConclusionsIn a small sample of predominantly racial minority school-aged children from low-income households, child diet quality is better during the school year vs summer. Future research is needed to determine if and to what extent summer vs school year diet quality may be associated with differences in weight status.