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.