Dietary Intake, Ecological Momentary Assessment, and Food Diaries: We Are What We Eat
Whether it’s a nutritious meat dish or a bowl of high-fat nuts, food intake is a key determinant for physical growth and cognitive development. The assimilation of nutrients plays a crucial role in human metabolism and the prevention of chronic illnesses. Given the prevalence of nutrition-related diseases, such as obesity, diabetes, cardiovascular disease, and dental problems; food intake assessments become fundamental in health care research and practice. Such evaluations can include dietary consumption data on foods, beverages, and supplements. Note that as food intake is not a static quality, eating assessments must be conducted in real-life settings to reflect the variety of food consumption, both in the short and the long-term.
Hence, ecological momentary assessments (EMAs), which are among the most reliable methods to assess a patient’s daily activities, can be employed as comprehensive and structured food diaries with high ecological validity and minimal recall bias. Interestingly, food diaries are defined as records of foods, portion sizes, eating schedules, nutrition statistics, environmental factors, and feelings. Digital ecological momentary assessment tools, in particular, can erase discrepancies in methodological heterogeneities in research and help users explore the pathways between dietary intake and health outcomes.
Ecological Momentary Assessments as Structured Food Diaries: Usage and Benefits
Dietary intake is a multifaceted phenomenon which lacks constant qualities. As consumption varies between meals and populations, ecological momentary assessments can improve the monitoring of food intake and provide high-quality data in real-life settings. Ecological momentary assessment methods are empirically validated structured diary techniques. Depending on the study design, ecological momentary assessments can be additionally divided into interval-contingent schedules, signal-contingent reports, event-contingent captures, and continuous reporting. Note that other common terms used to define ecological momentary assessment include experience sampling methods, ambulatory assessment, daily diary studies, real-time data capture studies, intensive longitudinal methods, and beeper studies. With high ecological validity and minimal recall bias, ecological momentary assessments reveal numerous benefits and applications:
- Momentary appetite and energy intake: Ecological momentary assessment can facilitate the understanding of eating behaviors, momentary appetite, and biopsychosocial factors affecting nutrition. Interestingly, Kikuchi and colleagues (2005) developed an ecological momentary assessment scale (a watch-type computer and a personal digital assistant-based food dairy) to evaluate participants’ (n=20) stress, mood, food intake, cravings, and appetite. The team found that momentary appetite was associated with high energy intake before meals, revealing high ecological validity of the tool.
Note that appetite is a vital patient-reported outcome, such as mood and pain experiences, as it affects eating behaviors and varies from moment to moment. Appetite is also a sensory response to food presentation, smell, previous experience, and even social pressure.
- Hedonic ratings and reward deficiency: Ecological momentary assessment tools can be implemented in the evaluation of food-reward perceptions, anticipation, food cravings, enjoyment, and eating behaviors. Interestingly, obesity rates are associated with people’s eating choices. Patients with higher body fat levels report fewer food wanting events per day and experience less food enjoyment after intake (Alabduljader et al., 2018). In other words, there’s a reward deficiency in obese individuals. Such findings should be implemented in dietary interventions to reduce dietary relapse and prevent nutrition-related diseases, especially in children and adolescents.
Interestingly, evidence shows that dietary lapses are associated with reduced coping strategies, both cognitive and behavioral. Carels and colleagues (2004) assessed 37 postmenopausal women via ecological momentary assessment diaries and found that coping strategies, mood, and abstinence-violation effects play a crucial role in weight-loss programs and relapse crises. Thus, ecological momentary assessment methods can be used to improve self-awareness and adaptive coping regarding temptations and dietary lapses.
- Daily activities and affect: Understanding the connection between eating behaviors and affect, as well as their effect on daily activities (e.g., sleep), is important to healthy and clinical populations. Ecological momentary assessment can be used to explore the psychological factors behind obesity and eating disorders and provide findings with high ecological validity. Although stress and negative emotions reveal a strong association with eating behaviors, evidence shows that positive emotions also play a crucial role in one’s diet. Macht et al. (2004) sampled 485 situations in a 7-day study and found that 37% of eating events occurred in emotionally positive situations, compared to 30% of eating situations classified as negative.
Additionally, Liao and colleagues (2018) examined high-fat/high-sugar food intake and food and vegetable consumption in 202 women via an electronic ecological momentary assessment. The team found that vegetable and fruit intake was associated with positive feelings. Interestingly, stress was a strong predictor for high-fat/high-sugar foods consumption, particularly in obese patients.
- Social desirability and social support: Ecological momentary assessment techniques can improve food intake assessment; such methods reduce recall and social desirability biases which often lead to under or over-reporting. In fact, real-life mobile-based ecological momentary assessments can improve the evaluation of weight-related behaviors and draw conclusions about the effects of social networks and support (Bruening et al., 2016).
Note that perceived social support can promote healthy behaviors. Given the fact that cultural differences also impact dietary intake, interventions must focus on traditional foods, family support, and religious beliefs.
Dietary Intake Assessments: Patient-reported Measures and Biomarkers
Given the active role of patients in health care decision-making, patient-reported outcomes and ecological momentary assessments, in particular, are becoming more and more popular in practice. Subjective measures provide vital information known only to the patients, improving nutrition surveillance studies, dietary guidance, and self-awareness. When it comes to self-reported methods, two categories exist: methods of real-time recording and methods of recall (Naska et al., 2017). Real-time records consist of food diaries (with or without weighing of foods) and the duplicate portion method (which includes chemical analysis of portions). Methods of recall include dietary histories, food frequency questionnaires (FFQs), and single or multiple daily recalls (24-hour dietary recalls).
Interestingly, subjective data can be supported by the analysis of biomarkers or biological specimen, which may correlate with dietary intake, metabolism, and personal characteristics (e.g.. smoking habits). Note that there are four categories of biomarkers: recovery, concentration, replacement, and predictive biomarkers. In addition, biomarkers can be categorized into short-term (measured in urine, plasma or serum), medium-term (measured in red blood cells or adipose tissue), and long-term biomarkers (measured in hair, nails, or teeth). The list of reliable nutrition biomarkers is increasing to improve dietary pattern analyses and food composition tables.
When it comes to subjective measures, it’s crucial to mention that food intake ability is associated with oral health-related quality of life and mental health. Choi and colleagues (2016) found that reduced subjective food intake ability due to poor oral health can lead to depression, self-esteem, and anxiety. Participants (n=72) completed subjective food intake ability tests, the Oral Health Impact Profile-14 scale, and three questionnaires about anxiety, self-esteem, and depression. Thus, research findings on self-reported masticatory ability are essential to improve both orthodontic treatment and dietary intake.
Ecological Momentary Assessment in Digital Health
With the rapid implementation of digital health technologies, electronic assessments have become reliable instruments to reduce respondent burden and reporting bias. While paper diaries were originally used in combination with pagers or watches, now personal digital assistants, wearable devices, and health applications facilitate the evaluation and monitoring of sampled experiences and eating behaviors. The use of digital platforms allows the integration of databases and pictures of foods, packaging material, and seasonal variations in intake. Electronic assessments also support data management and interoperability.
In fact, with high ecological validity and attractive design, digital dietary assessments reveal numerous benefits in the field of foods and diet patterns research:
- Digital self-reports increase ecological validity and compliance.
- Electronic real-time accounting of food facilitates data capture in real-time and provide time-stamps for the information collected.
- Digital ecological momentary assessment methods eliminate the need for laborious data input and expand interface design options.
Designing an Ecological Momentary Assessment (EMA) Food Diary
Since effective strategies to measure and improve diet and chronic diseases are a major focus of research, ecological momentary assessment studies are growing in popularity. Ecological momentary assessment can be employed as empirically validated and structured food diaries to help researchers explore behaviors, symptoms, and triggers, which vary between and within individuals. Ecological momentary assessments usually constitute of short questionnaires, and beep prompts. Questionnaires can include open-ended questions, visual analog scales or checklists to assess energy intake, food consumption, physical activity, environmental factors, emotional well-being, and social support. Interestingly, rating scales such as the visual analog scale are valid indices of temporal sensations (e.g., satiety, hunger, appetite) (Merrill et al., 2002). Most of all, evidence shows that self-assessments and daily logs improve patient outcomes related to physical activity and weight management (Burke et al., 2012).
Food diaries can help patients track aspects, such as:
- Type of food and drinks (e.g., high-calorie beverages)
- Healthy meals (e.g., high-fiber choices)
- Cravings (including snacking during the day)
- Time and date (with comments on eating schedules and patterns)
- Activities (e.g., eating while working)
- Mood (as well as social and emotional support)
When designing an ecological momentary assessment (EMA) food diary, researchers must decide either on a schedule (interval-contingent, signal-contingent, event-contingent, or continuous reporting) or a combined approach. Prompts and interface designs should be attractive and non-invasive. Interestingly, dietary self-monitoring can be influenced by daily and seasonal aspects (e.g., the beginning of the intervention, the day of the week, and month of the year). Note that Pellegrini and colleagues (2018) examined within-person differences in self-monitoring during a 6-month technology-supported weight loss trial, and found that lower adherence was recorded as the study progressed as well as on the weekends.
Ecological Momentary Assessment as Food Diary: Perspectives and Food Policy
Measuring diet is a challenging task. Food intake depends on various factors, such as body mass, appetite, social support, age, sex, and education. Therefore, only self-reports and food diaries can help health professionals assess dietary intake and its underlying mechanisms. Ecological momentary assessments, in particular, can be employed as effective diary techniques. Such measurements have high ecological validity, sensitivity, and accuracy. As these repeated assessments are conducted in real-life situations, the memory strains and burden to participants are reduced. Food diaries provide rich data on emotions, quality of life, social support, physical activity, and energy intake. Most of all, subjective measures empower patients, which is a leading goal in digital health practices worldwide. By becoming active participants in decision-making, patients can grasp a better understanding of their diet and eating behaviors.
After all, diet is defined as the main pathway between food environments and health outcomes, including in children. Interestingly, Campbell et al. (2018) found that factors in the family environment (e.g., eating alone or in front of the TV) influence eating behaviors in toddlers. The research team asked low-income mothers (n=277) to assess their home environment, and toddler’s eating habits through ecological momentary assessment, and performed multilevel logistic mixed-effects regression models to analyze the data. Note in the US alone; obesity rates are increasing, affecting 13.7 million children (aged 2-18 years). Thus, the adaptation of early healthy eating habits is vital to prevent chronic diseases and disabilities later in life.
In fact, digital ecological momentary assessment methods can benefit both interventions and informing policy. Understanding dietary intake among individuals can improve nutrition initiatives (e.g., school lunch initiatives) on local and national levels. Note that demographic factors and cultural differences influence people’s perceptions of obesity and dietary intake, so interventions should consider the integration of traditional foods and beliefs. Research findings can also improve food retail access, calorie labeling, food restrictions, and healthy choices.
- Alabduljader, K., Cliffe, M., Sartor, F., Papini, G., Cox, W., & Kubis, H. (2018). Ecological momentary assessment of food perceptions and eating behavior using a novel phone application in adults with or without obesity. Eating Behaviors, 30, p. 35-41.
- Bruening, M., Woerden, I., Todd, M., Brennhofer, S., Laska, M., & Dunton, G. (2016). A Mobile Ecological Momentary Assessment Tool (devilSPARC) for Nutrition and Physical Activity Behaviors in College Students: A Validation Study. JMIR.
- Burke, L., Wang, J., & Sevick, M. (2011). Self-Monitoring in Weight Loss: A Systematic Review of the Literature. Journal of the American Dietetic Association, 111 (1), p. 92-102.
- Campbell, K., Babiarz, A., Wang, Y., Tilton, N., Black, M., & Hager, E. (2018). Factors in the home environment associated with toddler diet: an ecological momentary assessment study. Public Health Nutrition, 21 (10), p. 1855-1864.
- Carels, A., Douglass, O., Cacciapaglia, H., & O’Brien, W. (2004). An Ecological Momentary Assessment of Relapse Crises in Dieting. Journal of Consulting and Clinical Psychology, 72 (2), p. 341-348.
- Choi, S., Kim, J., Cha, J., Lee, K., Yu, H., & Hwang, C. (2016). Subjective food intake ability related to oral health-related quality of life and psychological health. Journal of Oral Rehabilitation, 43 (9), p. 670-677.
- Kikuchi, H., Yoshiuchi, K., Shuji, I., Ando, T., & Yamamoto, Y. (2015). Development of an ecological momentary assessment scale for appetite. Biopsychosocial Medicine, 9 (2).
- Liao, Y., Schembre, S., O’Conner, S., Belcher, B., Maher, J., Dzubur, E., & Dunton, G. (2018). An Electronic Ecological Momentary Assessment Study to Examine the Consumption of High-Fat/High-Sugar Foods, Fruits/Vegetables, and Affective States Among Women. Journal of Nutrition Education and Behavior, 50 (6), p. 626-631.
- Macht, M., Haupt, C., & Salewsky, A. (2004). Emotions and eating in everyday life. Application of the experience sampling method. Ecology of Food and Nutrition, 43 (4), p. 11-21.
- Merrill, E., Kramer, F., Cardello, A., & Schutz, H. (2002). A comparison of satiety measures. Appetite, 39 (2).
- Naska, A., Lagiou, A., & Lagiou, P. (2017). Dietary assessment methods in epidemiological research: current state of the art and future prospects. F1000Research.
- Pellegrini, C., Conroy, D., Phillips, S., Pfammatter, A., McFadden, H., & Spring, B. (2018). Daily and Seasonal Influences on Dietary Self-monitoring Using a Smartphone Application. Journal of Nutrition Education and Behavior, 50 (1), p. 56-61.