Study design
This cross-sectional study focused on the eating habits, nutritional status, knowledge levels pertaining to nutrition, and the cooking methods and techniques of university students. For eligibility to participate, students had to be at least 18 years or older and pursuing a Bachelor’s degree in streams related to nutrition and culinary management at the Universidad Ana G. Mendez. The study protocol was submitted and approved by the university’s Institutional Committee for the Protection of Human Subjects in Research.
After study approval, the investigator coordinated with faculty members based on the academic calendar dates and time for the administration of the questionnaire within their classrooms. Once the students were present in the classrooms, the researcher provided information to all prospective participants regarding the study and its objectives, what participation would entail, including the measurement of weight and height for BMI estimation, and the length and duration of the self-administered questionnaire. Informed consent was provided to these students, with the information discussed by the researcher. Prospective participants were informed that no incentive for participation would be offered, and there were no penalties for discontinuing participation. Each student could drop out of the study at any time during the administration of the questionnaire by hand. Following this, those interested in participating voluntarily were provided the questionnaire. The researcher was present at all times during the administration of the questionnaire to clarify possible doubts and answer questions.
After students completed the self-administered questionnaire, the researcher obtained their weight and height values. An appropriate distance was established that separated participants whose values were being measured from the rest of the group to safeguard their privacy. These values were noted in the predetermined area of the questionnaire.
Survey development
To develop an instrument capable of measuring students’ eating habits, and knowledge in nutrition as well as cooking methods and cooking techniques, several existing instruments were reviewed. A panel of experts, comprising an expert in evaluation processes, a chef, a nutritionist-dietitian licensed to practice in Puerto Rico, and a doctor in nutrition, was consulted to review the initial instrument. After this, a pilot test was conducted on 16 students, to evaluate the ease of use and clarity of the instrument. Based on the results of the pilot study, items were revised, merged, or eliminated. In addition, content was reworded as needed to achieve good comprehension. The survey was also approved by the Academic Commission of the International Iberoamerican University UNINI México. This process promoted the adaptation of queries to meet linguistic and cultural aspects related to the sample under investigation, and questions from previously validated surveys were identified and used to develop the current questionnaire.
The initial survey comprised 170 items, with the final version comprising 164 items, including closed multiple-choice questions and assessment Likert Scales. The instrument was divided into four sections: student profile (socio-economic and personal characteristics), eating habits, knowledge in nutrition, and knowledge in cooking methods and cooking techniques.
The student profile section included questions regarding sociodemographic information such as age, sex, family composition, civil status, residence, income, and employment. In terms of education, students were asked about their year of study, career of choice, and if they were studying part-time or full time. Questions regarding the preparation of food in the residence, use of kitchen equipment and meal planning, caloric intake, type of diet, and physical activity were also included.
Specific questions regarding eating habits were used from the Youth Risk Behavior Surveillance System of the Center for Disease Control19 for the identification of unhealthy dietary behaviors. Additionally, questions from the “NHSGGC Community-based Cooking Skills Program Follow-up Questionnaire” by García et al.20 were also used since they assisted in the identification of barriers within cooking and healthy eating, and allowed for the measurement of elements in food planning, purchasing and food preparation from scratch. The Food Consumption Frequency Questionnaire by Goni et al.21 was also integrated, allowing for the identification of nutritional alterations caused by an inadequate diet, and observation of the possible quantity and quality of the foods consumed during a certain period of time as well as eating habits.
Students were asked about the frequency of consumption of foods and beverages in the last month to further measure their dietary diversity, and capture individual usual food consumption levels by obtaining data on the frequency with which the student consumed food items based on a predefined food list. Based on previous surveys, 19, 20, 21 the list included 34 items within the basic food groups (fruits, vegetables, proteins, dairy products, grains, fats), ways of consuming foods (boiled, fried) and, eating or cooking habits (eating out, cooking at home, ready-made meals, preparing from scratch). In addition, nine questions pertaining to food omission, food portions and weight loss strategies, and elements considered in the nutritional facts label were included to better identify and understand the application of healthy eating habits.
A section detailing the kind of meals that were consumed during the day (breakfast, lunch, dinner, and snacks) and which food groups were included in each of the daily meals was employed. Students were asked about the application of various cooking methods and techniques (boiled, steam, stew, fried, sautéed, roasted, grill, bake, and sous-vide) on a provided list of proteins, vegetables, and carbohydrates. This set of inquiries facilitated the investigation of the effect of students’ application of cooking methods and techniques on their food consumption.
An evaluative scale was developed for eating habits. According to each response, a score of 1 was assigned when adequate eating habits were applied according to the recommendation guidelines. Also, if the student consumed proteins, vegetables or carbohydrates in more than four cooking methods or techniques, one point was awarded. Contrarily, if the frequency of consumption, meals consumed during the day, food groups included in each meal were not in accordance with nutritional guidelines no points were given. Values between 0% and 69% were considered “Inadequate,” 70% and 79% “Satisfactory,” and 80% and 100% “Adequate.”
To measure the level of knowledge on nutrition and whether it was adequate, satisfactory or inadequate, 36 questions were adapted from a study by Tamayo et al.22 The questions acquired from this survey help in the recognition of the areas of limitation in students’ understanding of healthy eating habits. The questions included were based on the level of knowledge on nutritional recommendations regarding daily food and water intake, food groups in the plate, food portions and benefits of fiber consumption. Furthermore, the ability to identify the risk associated with the intake of excess salt and drinks with high concentrations of sugar, healthy cooking techniques and unhealthy fat intake, and yes/no questions about basic nutritional concepts pertaining to high-fiber foods, foods with cholesterol, nutritional fact labels, and healthy habits for portion control were also evaluated. Students were awarded one point when a correct answer was stated, and values between 0% and 69% were considered “Inadequate,” 70% and 79% “Satisfactory,” and 80% and 100% “Adequate.”
The section on cooking methods and techniques comprised 55 questions divided into three subsections: confidence in culinary competencies, knowledge in methods and techniques, and frequency of the application of cooking methods and techniques. Data from a previous study of culinary skills and consumption of processed or prepared foods in university students,23 as well as a cooking skills scale used in a study by Hartmann et al.24 were used for the development of this section. The selected sections of these surveys were included within this survey as they measured students’ cooking competencies and knowledge on how to cook, and their relationship with eating habits. Questions from the Basic Culinary Aptitude Questionnaire were also adapted, for the measurement of students’ knowledge levels and applicability of cooking methods and techniques.25 The General Knowledge Questionnaire on Nutrition and Food, pertaining to food, nutrients and alterations, or processes related to food, was used.26
Finally, a questionnaire on cooking skills based on a study by Ternier27 was used to determine if knowledge and skills in food preparation influenced food purchases and consumption. This section included a self-confidence scale for cooking competencies and questions on the use of cooking methods and techniques. One point was assigned when the student answered “Confident” or “Very confident” with regards to culinary competencies. In addition, we also employed yes/no questions for the identification of cooking methods and techniques, as well as recommended techniques for the nutrient retention of certain foods. If the student was able to answer the statement correctly one point was awarded. A Likert Scale (0 denoting “Never” and 3 “Always”) was also used to measure cooking frequency and practice. If the frequency of the application of culinary practices was “Most of the time” or “All the time” one point was awarded. Similar to the previous sections, values between 0% and 69% were considered “Inadequate,” 70% and 79% “Satisfactory,” and 80% and 100% “Adequate.”
Statistical analysis
Descriptive statistics such as frequency distributions, proportions, means and standard deviations (SDs) were used to summarize the data. Associations between categorical variables were measured using Fisher’s exact test or a Chi-Square test. Statistical significance was set at p<0.05. Data were analyzed using the Statistical Package for the Social Sciences (version 25, 2019 IBM SPSS Statistics)28 and R (version 3.4.4).29
Sample
The sample of this study comprised all university students pursuing a Bachelor’s degree at the Universidad Ana G. Méndez in Puerto Rico and who were enrolled in the following academic programs: Nutrition and Dietetics, Culinary Nutrition and Culinary Management. The total population comprised 93 students. As the target population was small, non-probabilistic intentional sampling was used, wherein the total population of the students of interest was chosen at the time of questionnaire administration. A total of 93 students completed the survey.