Situational characteristics of young adults' eating occasions: a real-time data collection using Personal Digital Assistants

Abstract

Objective

To examine: (a) situational characteristics of young adult eating occasions, including away-from-home eating, social influences, and multitasking, and (b) how these characteristics are associated with specific foods/beverages consumed.

Design

Participants logged numerous characteristics of eating occasions (n=1237) in real-time over 7 days.

Setting

Minneapolis/St. Paul metropolitan area (Minnesota, USA)

Subjects

Forty-eight participants, ages 18–3 years

Results

Half of all eating occasions (46%) occurred alone, 26% occurred while watching television and 36% involved other multitasking. Most participants (63%) did not think about their food choices in advance of eating occasions. Eating that occurred in the absence of television viewing and/or other multi-tasking was less likely to include sweetened beverages, and more likely to include items like water, fruit, vegetables, cereal, grains and entrées. Eating occasions occurring and/or those occurring at home, were more likely to include snack foods that required little preparation (e.g., cookies, baked goods), and less likely to include more traditional meal items (e.g., fruits, vegetables, entrée items).

Conclusion

Overall, a large proportion of young adult eating occasions occurred alone, while engaging in other activities and with little advanced planning. Although many young adult eating occasions consist of a wide range of highly processed, energy-dense, convenience products, more traditional meal settings (i.e., eating at home with others in the absence of multi-tasking) may result in more structured mealtimes and better food choices, such as more fruits and vegetables. Effective behavioral strategies promoting positive eating patterns, including home meal preparation, among young adults are urgently needed.

Introduction

Obesity is a major public health concern⁽¹, ²⁾. The transition from adolescence to adulthood is recognized as an influential age for excess weight gain, marked by poor dietary patterns and physical inactivity⁽³⁾. This age also represents an important time when many individuals move out of their family’s home, relocate to new environments and establish independent lifestyles. However, little scholarly work to date has examined the determinants of dietary behaviors and weight gain during this age⁽³⁾. In particular, we know little about contextual factors influencing eating and food choices among young adults. Given the unique attributes of the young adult years⁽³⁾, exploratory research is needed to better characterize meal patterns and the contextual factors associated with food choices that are most relevant to young adults’ lives.

Previous research suggests that the frequency of family meals is positively associated with dietary quality and other favorable outcomes among both children and adolescents^(4–9). However, once adolescents graduate from high school and begin to establish lifestyles independent from their families, their mealtime patterns may substantially decline in quality and structure and may shift to irregular times. Young adults are among the most frequent consumers of fast food, convenience products, and nutrient-poor dietary choices compared to other age groups. (See Nelson et al for a recent review of this literature⁽³⁾.) A significant proportion of young adults report eating “on-the-run,” and recent research suggests that such a style of eating is consistently associated with less favorable nutritional factors⁽¹⁰⁾. Furthermore, few young adults engage in some of the key practices known to contribute to healthy dietary intake, like home food preparation and meal planning⁽¹¹⁾.

Overall, scant research to date has examined issues around young adult meal patterning in detail, and young adult nutrition promotion interventions are urgently needed. However, in order to develop these types of behavioral intervention strategies and appropriate nutrition education messages for young adults, we first need a better understanding of young adult meal patterns, including the characteristics of and factors surrounding their meals and eating occasions. To address these gaps in the literature, the purpose of this study was to examine (a) situational characteristics of young adult eating occasions including away-from-home eating, social influences, multitasking during meals, timing of eating occasions and (b) how these situational characteristics were associated with specific types of foods/beverages consumed at meals and snacks.

Methods

Young adulthood represents a diverse set of lifestyle characteristics; as such, we recruited 48 participants (18–23 years, n=27 females) during 2008–2009 from four lifestyle groups: (a) attending college/university and living on-campus (n=12); (b) attending college/university and living independently from parents/family (off-campus) (n=12); (c) attending college/university and living with parents (n=12); and (d) not attending college/university and living independently from parents/family (n=12). Participants were recruited by posting flyers throughout 2- and 4-year colleges/universities and in coffee houses, shops, and on local websites (e.g., Craig’s List) frequented by young adults in the Minneapolis/St. Paul area. Participants were instructed to call or email study staff, who then assessed their eligibility for participation in the study. Study procedures were approved by the University of Minnesota Institutional Review Board.

In study visits at the University of Minnesota, participants completed a 38-item survey assessing food purchasing habits and relevant behaviors, and were given a Palm® Z22 handheld Personal Digital Assistant (PDA) device (http://www.palm.com/) to record their consumption of foods and beverages for the seven-day period between the two study visits. PDA devices were pre-programmed for food log entry using Pendragon Forms software (http://www.pendragonsoftware.com/). Participants were instructed to log every eating (and/or drinking) occasion during a 7-day period, as soon after the eating occasion concluded as possible. A pre-programmed script led participants through a series of 14 items used to characterize eating occasions, including the:

• Start and end time of eating occasion.

• Location type (e.g., home, workplace, school/university)

• Social context (“who was/is with you?”) (e.g., by yourself, one or more friends, one or more family members)

• Food/beverages consumed

• Other activities while eating (e.g., watching TV, using a computer) (hereafter referred to as “multitasking”)

• Pre-planning of food choices (Participants were asked: “Did you specifically think about what you would eat before you started eating? When did you start thinking about which foods or beverages you would select?” Response options included “No, just beforehand,” “Yes, about 30 minutes,” “Yes, a few hours before,” “Yes, more than a few hours before”)

Drop-down menus, including pre-set, categorical response options with an “other” category (which allowed for open-text entry), were available for nearly all questions. However, food and beverage entries were recorded entirely in free-text form, allowing participants to include appropriate descriptors of the food/beverages that they consumed. To minimize participant burden, beverages were only recorded if participants drank more than 1 cup (8-ounces) at one sitting. Participants were given detailed written instructions and in-person tutorials on how to use the PDA. Qualitative exit interviews with participants indicated that they were able to easily navigate the PDA program and felt comfortable doing so.

Other relevant data were self-reported by participants in survey form; these data included sociodemographic characteristics and current living situations.

Analysis

Analyses consisted of descriptive sample characteristics of young adult eating occasions (away-from-home eating, social context, multitasking during meals, timing of eating occasions), as well as how these situational characteristics were associated with specific types of foods/beverages consumed at meals and snacks. In all analyses, the unit of analysis was eating occasion; there were 1237 eating occasions among the 48 participants, with each participant reporting multiple eating occasions over the measurement week. The food data were coded using pre-existing categories adapted from existing protocols for another study, which used PDAs to collect food-related data (Away from home and out of school: Adolescent physical activity and BMI changes occurring with driving and eating out; PI: Deborah A. Cohen). Each food item recorded by a participant was placed in one category (for example; “muffin” was categorized as “Cookies and sweetened baked goods”). Categories were available for food items that were missing detail, for example “milk” was coded as “milk” while if a participant indicated that they drank “Skim milk” the category for “skim milk” was used. We did not attempt to document portion size of foods consumed.

All analyses controlled for the nested nature of the data (i.e., the multiple observations per participant). Logistic regression analyses were utilized to calculate all p-values (e.g., to determine whether the percent of participants eating and drinking specific foods and beverages at home were significantly different from the percentages of participants eating and drinking these foods and beverages away from home). In analyses comparing eating occasions that occurred at home versus away from home, participants living on college campuses (n=12) were considered to be eating “at home” when eating on campus, and “away-from-home” when off-campus. Preliminary analyses stratified by living situation indicated that in-home versus away-from-home comparisons were similar among participants not living on campus (n=36) and those living in dormitories (n=12); thus, for the ease of interpretation, these groups were combined and results are presented for the sample as a whole.

Analyses were conducted in 2010 using SPSS 17.0 (SPSS Inc., Chicago, IL, USA) and Stata 8.0 (Stata Corporation, College Station, TX, USA).

Results

Nearly half of the study participants were male (44%) (Table 1). Mean age was approximately 21 years, and 83% of the sample was white, reflecting the overall geographic region. By design, participants represented a range of lifestyle characteristics, including college enrollment status (not attending college, attending part-time, attending full-time), employment status, and living situation.

Table 1.

Descriptive characteristics of the young adult study sample, n=48.

	%, (n)
Gender
Male	44%, (21)
Female	56%, (27)
Age
18 years	15%, (7)
19 years	25%, (12)
20 years	19%, (9)
21 years	29%, (14)
22 years	10%, (5)
23 years	2%, (1)
Race*
White	83%, (40)
Black or African American	8%, (4)
Asian, Native Hawaiian or other Pacific Islander	8%, (4)
American Indian or Alaska Native	2%, (1)
Hispanic/Latino	2%, (1)
College status
Not attending college	25%, (12)
Attending college/university part-time	13%, (6)
Attending college/university full-time	62%, (30)
Employment status
Not employed	29%, (14)
Employed, <20 hours/week	40%, (19)
Employed, ≥20 hours/week	31%, (15)
Living situation
Living with parents	25%, (12)
Living on a college or university campus	25%, (12)
Living on own (in rented apartment/house or own home)	50%, (24)

^*Not mutually exclusive; participants were instructed to select all that apply.

Table 2 describes the situational and contextual differences in eating occasions that occurred at home versus away from home. Overall, approximately half of eating occasions (46%) occurred alone, 26% involved watching television, and 36% involved activities other than television. Nearly 40% of eating occasions lasted less than 15 minutes, and another 41% lasted 15-30 minutes. For a majority of eating occasions (63%), participants did not think about what they would eat or drink until immediately prior to the eating occasion. More than half (51%) of all eating events occurred between 11am and 7pm, another quarter (24%) occurred between 7pm and midnight, 21% occurred between 5am and 11am, and the remaining 4% of eating occasions were recorded between midnight and 5am.

Table 2.

Descriptive characteristics of eating occasions among the young adult study sample (n=48 participants).

		TOTAL	Location of eating occasion
			Home	Away-from-home
Eating occasions logged on PDA		100% (n=1237)	100% (n=892)	100% (n=345)
Social context
By myself		46%	51%	35%**
With friends or family		54%	49%	65%**
Other activities while eating
Not doing anything else (or talking in person with others)		57%	54%	65%*
Watching TV †		26%	30%	15%***
Activities other than watching TV †		36%	36%	38%
Duration of eating occasion
Less than 15 minutes		37%	39%	32%
15–30 minutes		41%	44%	34%***
More than 30 minutes		17%	13%	27%***
When did you starting thinking about what foods you would select for this meal/snack?
Just before starting to eat		63%	65%	58%
About 30 minutes before		23%	23%	24%
A few hours or more before		12%	10%	16%*
Timing of eating occasion (time of day)
7pm to midnight		24%	24%	25%
Midnight to 5am		4%	3%	5%*
5am to 11am		21%	23%	15%*
11am to 7pm		51%	50%	55%

Note: All values above are calculated based on the total eating occasions logged by 48 participants, except where otherwise noted.

^*Indicates p≤0.05,

^**Indicates p<.01,

^***Indicates p<.001 for differences in eating characteristics within subcategories of location (i.e., home vs. away-from-home), controlling for multiple observations among individual participants.

^†Categories are not mutually exclusive (i.e., participants could report watching TV as well as doing other activities, including using a computer, talking on the phone, text messaging, etc)

Compared to eating occasions that occurred away from home, at-home eating events were more likely to occur alone and to be accompanied by television viewing (p≤0.01) (Table 2). At-home eating occasions were also less likely to last at least 30 minutes (p≤0.001), and participants eating at home were less likely to have thought about what they would eat a few hours or more in advance of at-home eating (p≤0.05). In addition, a significantly larger proportion of away-from-home eating occasions occurred in the very early morning (between midnight and 4am), whereas a significantly larger proportion of at-home eating occasions occurred during typical breakfast hours (4am to 11am) (p≤0.05).

Table 3 details the types of foods and beverages consumed at home versus away-from-home. Eating occasions at home were more likely to include cookies and baked goods, milk, cereals and grains, but were less likely to include calorically sweetened beverages, entrée items and fried side dishes (p≤0.05). Among participants living in dormitories, on-campus (compared to off-campus) eating occasions were more likely to include fruits and vegetables (44% vs. 28%, respectively) and milk (28% vs. 11%), but less likely to include calorically sweetened beverages (11% vs. 25%) and salty snacks (13% vs. 25%) (all p-values ≤0.05) (data not shown).

Table 3.

Types of foods consumed by location of eating occasion.

	Examples of foods/beverages included in sub-categories	TOTAL	Location of eating occasion
			Home	Away-from- home
Eating occasions logged on PDA		100% (n=1237)	100% (n=892)	100% (n=345)
BEVERAGES (Non-alcoholic )
Calorically sweetened	Regular soda (not diet), energy drinks, juice drinks (not 100% juice), sports drinks, soda (no details given), juice drinks (no details given)	15%	12%	21%**
Water	Water (no details given)	17%	16%	17%
Coffee or tea drinks	Plain coffee, cappuccino, latte, specialty coffee drinks, tea (flavored or unflavored, hot or iced)	9%	9%	8%
Milk	Milk: skim, 1%, 2%, whole; plain or flavored	20%	24%	8%***
FOODS
Cookies and sweetened baked Goods	Animal crackers, graham crackers, cereal bars, energy/protein bars, cookies, doughnuts, cinnamon rolls, churro, granola bars, cakes, pies, brownies, muffins, scones, biscuits, Rice Krispie treats	32%	36%	23%***
Candy and gummy fruit snacks	Candy bars, hard candies, jelly beans, taffy, caramel, chewing gum	5%	4%	6%
Salty snacks	Potato chips, crackers, beef jerky, popcorn, pretzels, snack mixes, nuts, seeds, nachos	13%	12%	16%
Fruits and vegetables	Fresh fruit, fresh vegetables or salad, 100% juice, canned fruit, pickles, caramel apple, applesauce, dried fruit, baked/mashed potato, guacamole, salsa	31%	32%	31%
Frozen desserts	Frozen yogurt, popsicles, Italian ice, ice cream, frozen fruit juice	3%	2%	3%
Non-milk dairy products (non-frozen)	Cream cheese, pudding, cheese, yogurt (not frozen), smoothie, shakes	11%	12%	10%
Entrees	Frozen dinners, tacos, quesadillas, pizza, pizza rolls, sandwiches, wraps, hamburgers, cheeseburgers, soup, chili, sushi, chicken nuggets or wings, pasta, hot dogs, Chinese food, pork, beef, fish/seafood, poultry, tofu/tempeh, eggs, buffet, casserole	43%	41%	49%*
Cereals and grains	Granola/oatmeal, breakfast cereals, bagels, bread, breadsticks, rice, waffles, pancakes, French toast	28%	33%	17%***
Fried side dishes	French fries, tater tots, hash browns, potato skins, fried mozzarella sticks, onion rings	5%	4%	9%***

^*Indicates p≤0.05,

^**Indicates p<.01 for differences in food types within subcategories of location (i.e., home vs. away-from-home), controlling for multiple observations among individual participants.

NOTE: Some categories (low calorie beverages, other beverages, alcohol) are not included in the table because of their small sample size (i.e., appearing on ≤30 PDA records for the full sample).

Table 4 displays the extent to which the types of foods consumed at each eating occasion varied by situational characteristics, including social context and multitasking. Overall, eating occasions that occurred alone (versus with others) were more likely to include snack foods, such as cookies and sweetened baked goods, but were less likely to include calorically sweetened beverages, fruits and vegetables, entrée items, and fried side dishes (all p-values ≤0.05). Eating occasions that occurred in a more “traditional” meal setting (i.e., eating that occurred while not doing anything else, or while talking in person with others) were less likely to include calorically sweetened beverages and coffee/tea, and were more likely to include healthier meal items (such as water, fruit, vegetables, dairy, cereal and grains) as well as entrée items and fried side dishes, compared to eating events that occurred while watching television or multitasking (p≤0.05).

Table 4.

Types of foods consumed by contextual characteristics of young adult eating occasions.

	Social context †		Other activities while eating ‡
	By myself (reference category)	With others	Not doing anything else (or talking in person with others) (reference category)	Watching TV	Other activities
Eating occasions logged on PDA	100% (n=572)	100% (n=665)	100% (n=707)	100% (n=322)	100% (n=447)
BEVERAGES (Non-alcoholic)
Calorically sweetened	10%	18%*	15%	24%**	13%
Water	19%	15%	17%	12%*	17%
Coffee or tea drinks	10%	8%	6%	5%	13%**
Milk	19%	20%	23%	23%	11
FOODS
Cookies & sweetened baked goods	37%	28%**	33%	29%	31%
Candy and gummy fruit snacks	4%	5%	5%	5%	7%
Salty snacks	12%	14%	14%	15%	17%
Fruits and vegetables	27%	35%*	36%	26%**	27%**
Fresh fruits/vegetables	19%	26%*	27%	16%**	18%**
Other	12%	16%*	16%	12%	13%
Frozen desserts	2%	3%	3%	3%	3%
Non-milk dairy products (non-frozen)	11%	11%	11%	10%	11%**
Entrees	33%	52%**	49%	46%	32%**
Cereals and grains	30%	27%	31%	25%*	22%*
Fried side dishes	3%	7%*	7%	4%	2%**

^*Indicates p≤0.05,

^**Indicates p<.01 for differences in food types within subcategories of social context, activities while eating, and pre-planning of food selections, controlling for multiple observations among individual participants.

^†For social context, statistically significant differences are compared to “by myself.”

^‡For activities while eating, statistically significant differences are compared to “Not doing anything else (or talking in person with others),” which was the reference group in analyses. ”Other activities” designation comprised of the following self-reported responses: using a computer, driving/riding in vehicle, reading, talking on phone/text message, and other. Categories are not mutually exclusive (i.e., participants could report watching TV as well as doing other activities, including using a computer, talking on the phone, text messaging, etc)

Table 5 details the differences in the types of foods consumed by time of day. Compared to eating occasions that occurred between 11am and 7pm, those occurring late at night (7pm to midnight) and/or in the early morning (midnight to 5am) were less likely to include milk, fruits and vegetables, and entrée items and were more likely to include salty snacks (p≤0.05). Eating occasions occurring between 5am and 11am were less likely than those occurring between 11am and 7pm to include calorically sweetened beverages, salty snacks, fresh fruits and vegetables, entrée items and fried side dishes, and were more likely to include coffee or tea drinks, milk, cookies and sweetened baked goods, and cereals and grains (p≤0.05).

Table 5.

Types of foods consumed by young adults across various times of day.

	Time of eating occasion
	7:01pm – 12:00am	12:01am – 5:am	5:01am – 11:00am	11:01am – 7:00pm† (reference category)
Eating occasions logged on PDA‡	100% (n= 297)	100% (n=47)	100% (n=250)	100% (n= 623)
BEVERAGES (Non-alcoholic)
Calorically sweetened	17%	21%	6%**	17%
Water	16%	32%	14%	18%
Coffee or tea drinks	8%	13%	16%**	6%
Milk	8%*	6%*	34%**	20%
FOODS
Cookies and sweetened baked goods	26%	19%	52%**	28%
Candy and gummy fruit snacks	7%	6%	1%	4%
Salty snacks	20%*	13%	2%**	14%
Fruits and vegetables	23%**	11%**	30%	36%
Fresh fruits/vegetables	15%**	6%**	17%**	29%
Other	10%	4%	17%	15%
Frozen desserts	3%	4%	<1%*	3%
Non-milk dairy products (non-frozen)	10%	4%	10%	12%
Entrees	39%**	30%**	18%**	57%
Cereals and grains	18%	19%	52%**	24%
Fried side dishes	6%	4%	2%*	6%

^*Indicates p≤0.05,

^**Indicates p<.01 for differences in food types within subcategory of time of eating occasion, controlling for multiple observations among individual participants.

^†For time of eating occasion, statistically significant differences are compared to “11:01am – 7:00pm,” which was the reference group in analyses.

^‡For a limited number of eating occasions (n=20, 1.6%), time was not recorded.

Discussion

The purpose of this research was to examine situational characteristics of young adult eating occasions including away-from-home eating, social influences, multitasking during meals, and timing of eating occasions, as well as to examine how these situational characteristics were associated with specific types of foods and beverages consumed throughout the day. Participants in this study logged various characteristics of all eating occasions (n=1,237) over a one-week period. Our findings indicate that in our young adult sample, a large proportion of eating occasions occurred alone, while watching TV or engaging in other activities, were completed within a 15-minute timeframe and occurred with virtually no pre-contemplation or planning of food choices or meal selections. Previous research indicates that factors such as planning one’s meals ahead of time and eating in the absence of other activities (e.g., television viewing) may be key determinants of healthy dietary patterns⁽¹², ¹³⁾; as such, these may be important target areas for future nutrition promotion interventions among young adults.

In addition, these findings indicated that among young adults, at-home eating occasions were associated with higher intakes of certain snacks and convenience foods (such as cookies and sweetened baked goods) and fewer traditional meal items (such as entrees, fruits and vegetables), as compared to away-from-home eating occasions. These results may represent a phenomena that is somewhat unique to this age group. Overall, nearly half of all adults in the U.S. report eating three or more meals each week that have been commercially prepared away from home⁽¹⁴⁾, including a large proportion from fast food restaurants⁽¹⁵⁾. Compared to meals prepared at home, commercially-prepared meals have been shown to generally contain more energy, fat, sodium and cholesterol, as well as lower levels of beneficial nutrients (e.g., fiber, calcium)⁽¹⁶⁾. Given that the young adult age group is among the most frequent consumer of fast food and convenience food products⁽³⁾, these issues present serious concerns that may, at least in part, account for the substantial excess weight gain and poor nutritional status observed at this age. Of even greater concern, however, is the fact that young adults may be becoming increasingly ill-equipped to prepare healthy meals at home, lacking either the knowledge, skills, resources, time and/or motivation to prepare food on their own⁽¹¹⁾. Our findings highlight the fact that many young adults are consuming foods at home that require little to no preparation, such as cookies, baked goods, and cereal, and may be lacking the fundamental knowledge and skills equipping them to cook healthy meals at home. The significance of these issues is underscored by the fact that these are young adults of reproductive age who soon may be starting families of their own.

Findings from this study also suggest that more traditional meal settings (i.e., eating with others in the absence of multitasking) may be associated with several healthier dietary characteristics, including the consumption of more fruits and vegetables and/or fewer cookies and sweetened baked goods. Previous research has shown that although a majority of young adults enjoy and value eating with others, many report a lack of time to sit down and eat structured meals with others⁽¹⁰⁾. Research by Larson et al from Project EAT (Eating Among Teens), a large population-based cohort study of adolescents transitioning into young adulthood, has shown that eating meals with others is associated with better overall dietary quality, including higher intake of fruits, vegetables, calcium and fiber, as well as lower intake of fat and saturated fat.¹⁰ These findings are also supported by a growing body of research suggesting that children and adolescents who report more frequent family meals have more favorable intakes of fruits, vegetables and several key nutrients⁽⁵⁾. Overall, more effort is needed to support young adults in engaging in thoughtful and healthful food choices. Encouraging structured meal settings that are socially engaging may be an important mechanism through which these behaviors could be supported.

Although we found that most young adult eating occasions occurred during the day (11am to 7pm), a notable proportion occurred later at night. Approximately one-quarter of eating events occurred between 7pm and midnight, and a relatively small percent (4%) occurred between midnight and 5am. Late night eating events were less likely to include healthier items, such as fruits, vegetables and milk, and more likely to consist of salty snacks eaten away from home. Limiting the excess calories consumed during late night eating events may be an important issue to be addressed among young adults in order to prevent weight gain over time. In general, promoting healthy choices during typical breakfast hours may also be needed among young adults; our findings indicate that young adults who ate breakfast during these hours were more likely to make some healthier choices (e.g., more cereals, grains, milk), and were less likely to make others (e.g., more sweetened baked goods, less fresh fruit).

Recently, there has been a widespread call to “Bring Back Home Economics Education,” as described in the recent editorial in the Journal of the American Medical Association with this title by Lichtenstein and Ludwig⁽¹⁷⁾. Frequent home food preparation has been associated with better dietary outcomes among both adolescents and young adults^{(11, 18)}, and is often cited as a critical skill that is lacking among these age groups. Interestingly, however, recently national survey data indicate that the proportion of students enrolled in Family and Consumer Science (i.e., “home economics”) programs in U.S. secondary schools has not changed since the 1950s⁽¹⁹⁾. It is unlikely that these courses alone are sufficient in equipping adolescents to begin a life-long habit of healthy home food preparation. More intensive effort needs to be invested in helping adolescents and emerging adults develop the skills by which to prepare healthy meals at home on most nights of the week and to sustain such long-term healthful lifestyle habits and cope with the obesigenic environments in which we live. Comprehensive efforts will need to be targeted not only within schools, but also within family, home and community settings.

Nutrition promotion efforts that are specifically targeted toward young adults are urgently needed. The findings from this research provide a better understanding of the contexts in which young adults eat, which are important in developing more relevant nutrition promotion interventions and nutrition education messaging for this age group. Although we are lacking data on specific nutrient intake within this study, many of the food and beverage items recorded by participants on the PDA food logs were generally calorically dense and not of high nutritional quality. For example, many of the entrees reported here could be described as “convenience foods” and/or “fast foods,” including frozen dinners, tacos, pizza, hamburgers, chicken fingers and wings. Different dietary assessment methods (e.g., 24-hour recalls) are needed in future studies to explore the nutrient composition of participants’ dietary intakes in a more precise way. Although our data collection methodology was limited in this respect, it allowed us to capture a wide range of contextual characteristics that occur around mealtimes, which are not typically available from 24-hour dietary recalls. In addition, qualitative exit interviews conducted in this study suggested that participants may have been able to more readily log this wide array of mealtime factors due to the real-time nature of this data collection.

An additional important limitation of this study is the small sample size. Despite the fact that data were collected on over 1,200 eating events, these data were collected from 48 young adult participants, which limits our ability to examine differences within specific sub-groups of participants (e.g., by gender, age group, or lifestyle characteristics). Although future research is needed among larger samples to explore these issues in greater depth, such data collection among large samples may be logistically challenging, particularly given that the scoring of these data (e.g., categorizing food types) can be a very time-intensive and laborious process for research staff. Therefore, these time- and labor-intensive methods may be best utilized for small-scale, exploratory and hypothesis-generating research studies, which may then inform more targeted data collection in larger samples. For example, it would be possible to add data collection on a limited number of specific contextual features of interest to 24-hour dietary recall data collection within larger study samples, in order to obtain meal-specific data on contextual factors. In addition, carefully obtained 24-hour recall data may also be used to better understand the association between the timing of eating occasions throughout the day and overall dietary quality.

In summary, additional work is needed to promote healthy, at-home food preparation and eating among young adults and in the population as a whole. In a recently released report, the 2010 U.S. Dietary Guidelines Advisory Committee identified nine key changes that are needed in the overall food environment in order to support Americans in meeting the recommendations of the Dietary Guidelines. The first change identified in their report is to “improve nutrition literacy and cooking skills, including safe food handling skills, and empower and motivate the population … to prepare and consume healthy foods at home.⁽²⁰⁾” The transition from adolescence to young adulthood may be an important age for acquiring and reinforcing these skills⁽¹¹, ¹⁸⁾. Overall, this is a particularly influential developmental age for excess weight gain and poor dietary habits⁽³⁾, and most young adults fail to meet national recommendations for health. Establishing more structured and routine meal patterns and preparing healthy foods at home are major challenges for many young adults today. Effective strategies to promote healthy eating patterns, including home meal preparation, among young adults are urgently needed.