Isocaloric meal and snack foods differentially affect eating behavior

Association of malnutrition and main-meal- and snack-predominant intake among female adolescent students in boarding schools in Tasikmalaya, Indonesia

Background: Balanced dietary intake is needed to prevent malnutrition which is one of the nutritional problems faced by adolescents. Aim: To study the association between predominant dietary intake and nutritional status of female adolescent students in boarding schools in Tasikmalaya, Indonesia. Method: This cross-sectional study was conducted on 323 female adolescent students residing full-time in eight boarding schools in Tasikmalaya, West Java. Students' dietary intake was measured using the 3-non-consecutive-day 24-h recall method. The association between the predominant dietary intake and nutritional status was evaluated using binary logistic regression. Results: Of the 323 students, 59 (18.3%) were overweight/obese (OW/OB) and 102 (31.6%) had stunted growth. The predominant dietary intake in the OW/OB group was snacks, whereas, in the stunted group, it was main meals. Snack-predominant dietary intake was a risk factor for overweight and obesity (p  =  0.008; adjusted odds ratio [AOR]: 2.276; 95% confidence interval [CI]: 1.244-4.164), but it was a protective factor against stunting (p  =  0.008; AOR: 0.521; 95% CI: 0.322-0.842). Conclusion: The predominance of main meals and snacks as components of total dietary intake affected the nutritional status of female adolescent students living in boarding schools. Therefore, the dietary intake interventions should tailor and design the nutritional contents of main meals and snacks according to the nutritional status of the targeted individuals.

Evaluating and communicating about the healthiness of foods: Predictors of parents' judgments and parent-child conversations

Parents are typically in charge of purchasing the food that their children eat, but little is known about how parents decide if particular foods are healthy for their children and how their beliefs about nutrition influence their children's beliefs. In two studies, we investigated how parents of children ages 4 to 12 (N = 826) make decisions about the healthiness of foods, when presented with different representations of the same nutritional information. Providing parents with nutritional information did not influence their ratings of how healthy food items are, compared to when they are shown only pictures of the foods. Parents reported talking with their children about nutrition, believed they are the best source of information for children about nutrition, and believed their nutrition beliefs influence their child's beliefs. Our findings highlight the role of prior knowledge in food cognition and how beliefs about foods are transmitted from parents to children.

Expectations About Satiety and Thirst Are Modified by Acute Motivational State

Prior research has shown that consumers have clear and measurable expectations about the likely effects of food and drink items on their appetite and thirst, which are acquired with experience and influenced by a product's taste and texture. What is unclear is whether expression of these expectations also varies with current appetitive state. It is possible that current appetite could increase or decrease the relevance of these expectations for future food choice and magnify a product's expected impact on appetite. To test this, we contrasted expectations about satiety and thirst for four products consumed 2 h after an appetite manipulation at breakfast, achieved through ad libitum access to low-energy drinks only (hunger condition), cereal only but no drinks (thirst condition) or both foods and drinks (sated condition). The test products were two soups and two drinks, with a thicker and thinner version of each product type to act as positive control to ensure sensitivity in detecting differences in expectations. For satiety, the predicted differences between products were seen: soups and thicker products were expected to be more filling and to suppress subsequent hunger more than drinks and thinner products, but these differences were more pronounced in the hunger than thirsty or sated conditions. Being thirsty also enhanced expectations of how much drinks would appease immediate thirst. Overall the data show that expectations were adjusted subtly by a person's current appetitive state, suggesting that we have mechanisms that highlight the most important features of a product at the time when it may be most beneficial to the consumer.

What Is a Snack, Why Do We Snack, and How Can We Choose Better Snacks? A Review of the Definitions of Snacking, Motivations to Snack, Contributions to Dietary Intake, and Recommendations for Improvement

Around the world, adults consume energy outside of traditional meals such as breakfast, lunch, and dinner. However, because there is no consistent definition of a "snack," it is unclear whether those extra eating occasions represent additional meals or snacks. The manner in which an eating occasion is labeled (e.g., as a meal or a snack) may influence other food choices an individual makes on the same day and satiety after consumption. Therefore, a clear distinction between "meals" and "snacks" is important. This review aims to assess the definition of extra eating occasions, to understand why eating is initiated at these occasions, and to determine what food choices are common at these eating occasions in order to identify areas for dietary intervention and improvement. Part I of this review discusses how snacking is defined and the social, environmental, and individual influences on the desire to snack and choice of snack. The section concludes with a brief discussion of the associations of snacking with cardiometabolic health markers, especially lipid profiles and weight. Part II addresses popular snack choices, overall snacking frequencies, and the demographic characteristics of frequent snackers in several different countries. This review concludes with a recommendation for nutrition policymakers to encourage specific health-promoting snacks that address nutrient insufficiencies and excesses.

Association between meal intake behaviour and abdominal obesity in Spanish adults

The study aims to evaluate the association between abdominal obesity with meal intake behaviour such as having a forenoon meal, having an afternoon meal and snacking. This cross-sectional study includes n = 1314 participants aged 20-79 who were interviewed during the Cardiac health "Semanas del Corazon" events in four Spanish cities (Madrid, Las Palmas, Seville and Valencia) in 2008. Waist circumference, weight and height were assessed to determine abdominal obesity (waist circumference: ≥88 cm in women and ≥102 cm in men) and BMI, respectively. The intake of forenoon and afternoon meal and snacking between the participants' regular meals were assessed with a questionnaire that also included individual risk factors. The information obtained about diet was required to calculate an Unhealthy Habit Score and a score reflecting the Achievement of Dietary Guidelines. Adjusted logistic regressions were used to examine the association between abdominal obesity and the mentioned meal intake behaviour controlling for sex, age, individual risk factors, BMI and diet. Having an afternoon meal (OR 0.60; 95% CI (0.41-0.88)) was negatively associated with abdominal obesity after adjusting for all confounders, whereas the positive association of snacking (OR 1.39; 95% CI (1.05-1.85)) was not independent of BMI (OR 1.25; 95% CI (0.84-1.87)). Taking a forenoon meal did not show any associations (OR 0.92; 95% CI (0.63-1.34)) with abdominal obesity. The results obtained could be helpful in the promotion of healthy habits in nutritional education programmes and also in health programmes preventing abdominal obesity.

Fluid or fuel? The context of consuming a beverage is important for satiety

Energy-containing beverages have a weak effect on satiety, limited by their fluid characteristics and perhaps because they are not considered 'food'. This study investigated whether the context of consuming a beverage can influence the satiating power of its nutrients. Eighty participants consumed a lower- (LE, 75 kcal) and higher-energy (HE, 272 kcal) version of a beverage (covertly manipulated within-groups) on two test days, in one of four beverage contexts (between-groups): thin versions of the test-drinks were consumed as a thirst-quenching drink (n = 20), a filling snack (n = 20), or without additional information (n = 20). A fourth group consumed subtly thicker versions of the beverages without additional information (n = 20). Lunch intake 60 minutes later depended on the beverage context and energy content (p = 0.030): participants who consumed the thin beverages without additional information ate a similar amount of lunch after the LE and HE versions (LE = 475 kcal, HE = 464 kcal; p = 0.690) as did those participants who believed the beverages were designed to quench-thirst (LE = 442 kcal, HE = 402 kcal; p = 0.213), despite consuming an additional 197 kcal in the HE beverage. Consuming the beverage as a filling snack led participants to consume less at lunch after the HE beverage compared to the LE version (LE = 506 kcal, HE = 437 kcal; p = 0.025). This effect was also seen when the beverages were subtly thicker, with participants in this group displaying the largest response to the beverage's energy content, consuming less at lunch after the HE version (LE = 552 kcal, HE = 415 kcal; p<0.001). These data indicate that beliefs about the consequences of consuming a beverage can affect the impact of its nutrients on appetite regulation and provide further evidence that a beverage's sensory characteristics can limit its satiating power.

Estimating food portions. Influence of unit number, meal type and energy density

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University staff/students showed poor awareness of appropriate portion sizes.

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Unit number and meal classification affected portion size estimation.

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Portion sizes in sugary drinks, pizza and pasta were underestimated by 30–46%.

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Women were better at estimating food portion sizes than men.

Estimating how much is appropriate to consume can be difficult, especially for foods presented in multiple units, those with ambiguous energy content and for snacks. This study tested the hypothesis that the number of units (single vs. multi-unit), meal type and food energy density disrupts accurate estimates of portion size. Thirty-two healthy weight men and women attended the laboratory on 3 separate occasions to assess the number of portions contained in 33 foods or beverages of varying energy density (1.7–26.8 kJ/g). Items included 12 multi-unit and 21 single unit foods; 13 were labelled “meal”, 4 “drink” and 16 “snack”. Departures in portion estimates from reference amounts were analysed with negative binomial regression. Overall participants tended to underestimate the number of portions displayed. Males showed greater errors in estimation than females (p = 0.01). Single unit foods and those labelled as ‘meal’ or ‘beverage’ were estimated with greater error than multi-unit and ‘snack’ foods (p = 0.02 and p < 0.001 respectively). The number of portions of high energy density foods was overestimated while the number of portions of beverages and medium energy density foods were underestimated by 30–46%. In conclusion, participants tended to underestimate the reference portion size for a range of food and beverages, especially single unit foods and foods of low energy density and, unexpectedly, overestimated the reference portion of high energy density items. There is a need for better consumer education of appropriate portion sizes to aid adherence to a healthy diet.

Episodic memory and appetite regulation in humans

Psychological and neurobiological evidence implicates hippocampal-dependent memory processes in the control of hunger and food intake. In humans, these have been revealed in the hyperphagia that is associated with amnesia. However, it remains unclear whether ‘memory for recent eating’ plays a significant role in neurologically intact humans. In this study we isolated the extent to which memory for a recently consumed meal influences hunger and fullness over a three-hour period. Before lunch, half of our volunteers were shown 300 ml of soup and half were shown 500 ml. Orthogonal to this, half consumed 300 ml and half consumed 500 ml. This process yielded four separate groups (25 volunteers in each). Independent manipulation of the ‘actual’ and ‘perceived’ soup portion was achieved using a computer-controlled peristaltic pump. This was designed to either refill or draw soup from a soup bowl in a covert manner. Immediately after lunch, self-reported hunger was influenced by the actual and not the perceived amount of soup consumed. However, two and three hours after meal termination this pattern was reversed - hunger was predicted by the perceived amount and not the actual amount. Participants who thought they had consumed the larger 500-ml portion reported significantly less hunger. This was also associated with an increase in the ‘expected satiation’ of the soup 24-hours later. For the first time, this manipulation exposes the independent and important contribution of memory processes to satiety. Opportunities exist to capitalise on this finding to reduce energy intake in humans.

Satiety following intake of potatoes and other carbohydrate test meals

BACKGROUND AND AIMS

The study investigated satiation and satiety following intake of starch-rich side dishes representing a range of glycemic indices (GIs).

METHODS

Twelve normal-weight (BMI = 22.4 ± SD 2.0) participants (6 male, 6 female, 22-30 years) received one of four side dishes or white bread (GI reference) in randomized order on five mornings, followed by an ad libitum lunch. Blood draws prior to test meal and during the 2 h before lunch measured plasma glucose and insulin concentrations. GI was calculated from glucose incremental area under the curve (AUC). Hunger, fullness, desire to eat and prospective consumption were rated just before blood draws.

RESULTS

No significant difference was found in hunger or fullness AUCs between test meals. Both potato meals yielded lower desire to eat compared to pasta throughout the 2-hour period (p = 0.002). Total lunch energy intake did not differ. No significant correlations were found between test meal GI and ratings of hunger, fullness or energy intake at lunch meal.

CONCLUSIONS

GI of energy-equivalent test meals did not predict satiety or lunch meal intake. There was evidence of reduced appetite following both potato meals relative to the other carbohydrate side dishes but no differences in subsequent intake.

Categorization of foods as "snack" and "meal" by college students

The cognitive representation of a food as being a "snack" or a "meal" influences eating behavior. We found previously that subjects who considered a particular food to be a 'snack' ate significantly more calories when tested later than subjects who considered the same foods as a 'meal'. We conducted two surveys to determine the categorization of foods as "snacks" or "meals". Survey 2 included a larger variety of foods with detailed descriptions and a response option of "never tried". Both surveys found that potato chips, crackers, cookies, and nuts were consistently viewed as snacks, while soups, burritos, pizza, and pancakes were consistently viewed as meals. Useful for future research are foods we found that students varied in considering a snack or meal. Survey 1 found that half the respondents viewed toast, cheese on toast, muffins, and French fries as snacks and the other half as meals. Similarly, in Survey 2 potato salad, toast with jam, English muffin, cinnamon rolls, and nachos were categorized almost equally as snack and meal. These foods can be used in studies looking at the effects of categorizing a food as a meal or snack on other behaviors or categorization, while controlling for the food item.

The influence of eating rate on satiety and intake among participants exhibiting high dietary restraint

BACKGROUND

Studies show inconsistent results with regards to whether eating slower can enhance satiety and reduce intake in a meal. Some methodological differences are apparent and could potentially explain why results are not consistent across studies.

OBJECTIVE

To determine whether eating slower can enhance satiety and reduce intake when rate of eating is manipulated and not manipulated in a kitchen setting using a sample of participants who exhibit high dietary restraint (HDR).

DESIGN

Two samples of college students who exhibit HDR, which is a group likely to use behavioral strategies to manage intake, were selected in a prescreening session. Participants were told how fast or slow to eat (Variation 1) or allowed to eat at their own pace (Variation 2). Self-reported satiety during the meal and amount consumed was recorded. The types of foods, macronutrient intakes, weights of foods, order of food intakes, and the dimensions of foods were held constant between groups to control for group differences in the sensory and hedonic qualities of the meals.

RESULTS

Eating slower enhanced mid-meal satiety ratings, but only when instructions were given to eat fast or slow (Variation 1). In both variations, eating slower did not reduce amount consumed in the meal, although each variation had sufficient power to detect differences.

CONCLUSION

Eating slower is not likely to be an effective strategy to control intake in a meal among those exhibiting HDR.

'Expected satiety' changes hunger and fullness in the inter-meal interval

Previously, we have shown that foods differ markedly in the satiety that they are expected to confer (compared calorie-for-calorie). In the present study we tested the hypothesis that 'expected satiety' plays a causal role in the satiety that is experienced after a food has been consumed. Before lunch, participants (N=32) were shown the ingredients of a fruit smoothie. Half were shown a small portion of fruit and half were shown a large portion. Participants then assessed the expected satiety of the smoothie and provided appetite ratings, before, and for three hours after its consumption. As anticipated, expected satiety was significantly higher in the 'large portion' condition. Moreover, and consistent with our hypothesis, participants reported significantly less hunger and significantly greater fullness in the large-portion condition. Importantly, this effect endured throughout the test period (for three hours). Together, these findings confirm previous reports indicating that beliefs and expectations can have marked effects on satiety and they show that this effect can persist well into the inter-meal interval. Potential explanations are discussed, including the prospect that satiety is moderated by memories of expected satiety that are encoded around the time that a meal is consumed.

The satiety effect of disguised liquid preloads administered acutely and differing only in their nutrient content tended to be weaker for lipids but did not differ between proteins and carbohydrates in human subjects

Whether protein is the macronutrient with the strongest satiety effect remains a matter of debate because of the diversity of study designs employed. The aim of the present study was to compare the effect of different liquid preloads made up of proteins, fats or carbohydrates only, under stringently controlled conditions, on satiety. Fifty-six subjects participated in the present study which consisted of four randomised test days, i.e. 1 d per macronutrient and one control day. During each test day, the subjects were required to consume the preload in full, and then their subsequent food intake was measured. The volunteers were divided into two groups: the first (T0) group, which consumed the preload immediately before lunch, and the second (T1) group, which consumed it 1 h beforehand. The main results showed that the participants consumed significantly less at lunch following the consumption of all three preloads than on the no-preload day, and consumed less after the consumption of the carbohydrate preload than after the consumption of the lipid preload. When energy from the preload was included, overall energy intake was significantly greater in all the three preload conditions than in the situation involving no preload, with only partial compensation for preload energy in all conditions. Total daily energy intake was highest after the lipid preload ingestion, but this could be a chance finding since it was not significantly higher than that observed after protein or carbohydrate preload ingestion. No significant effects of the interval between the preload and test meal ingestion were found. These results do not confirm the greater satiety effect of proteins than of carbohydrates, but partially confirm the weaker effect of fats.

Intake during repeated exposure to low- and high-energy-dense yogurts by different means of consumption

BACKGROUND

An important question in the regulation of energy intake is whether dietary learning of energy content depends on the food's characteristics, such as texture. Texture might affect the duration of sensory exposure and eating rate.

OBJECTIVE

The objective was to investigate whether a long sensory exposure, due to differences in means of consumption and in viscosity, enhances learned associations between sensory signals and metabolic consequences and hence facilitates energy intake compensation.

DESIGN

A total of 105 healthy young adults with a mean (+/-SD) age of 22 +/- 3 y and a body mass index (in kg/m(2)) of 21.6 +/- 1.7 participated in a parallel intervention in 3 groups: liquid yogurt with a straw (liquid/straw; n = 34), liquid yogurt with a spoon (liquid/spoon; n = 36), or semisolid yogurt with a spoon (semisolid/spoon; n = 35). Novel flavored yogurts were offered ad libitum for breakfast in 2 energy densities: low ( approximately 215 kJ/100 g) and high ( approximately 600 kJ/100 g). Subjects were repeatedly exposed to the yogurt products (10 times), and yogurt intake was measured.

RESULTS

Intakes (P = 0.01) and eating rates (P = 0.01) were highest in the liquid/straw group. Average intakes over 10 exposures were 575 +/- 260 g for liquid/straw, 475 +/- 192 g for liquid/spoon, and 470 +/- 223 g for semisolid/spoon; average eating rates were 132 +/- 83 g/min for liquid/straw, 106 +/- 53 g/min for liquid/spoon, and 105 +/- 88 g/min for semisolid/spoon. No significant interaction for intake between intervention group, energy density, and repeated exposure was observed, and intakes of the low- and high-energy-dense yogurts did not change over time in any of the intervention groups.

CONCLUSIONS

We observed no energy intake compensation after repeated exposure to yogurt products. Differences in ad libitum yogurt intake could be explained by eating rate, which was affected by the different means of consumption. This trial was registered with the Dutch trial registration at http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1853 as NTR1853.