Participants
This is a repeated cross-sectional study was conducted in two time intervals between May and August 2018 and enrolled 62 participants recruited from three diet clinics in Lebanon (two in Mount Lebanon and one in Beirut). The patients were first time enrolled in May 2018 and another assessment for the same participants was done after 12 week on August 2018.
Eligible participants were all healthy individuals 18 years and older, newly consulting for weight loss at a diet clinic. Those with concurrent disease or clinical psychopathology, known to alter weight, were excluded. For the purpose of this study, all three clinics adopted the same 12-week weight loss program. Before enrolling, the head dietitian briefed participants on the study objectives and methodology and assured them of the anonymity of their participation. They had the right to accept or refuse to participate, and no financial compensation was offered in exchange for their participation. The main motivation of the participants for weight loss was improvements in appearance by lowering their weight, self‐confidence and energy level.
Sample size calculation
The G-Power software version 3.1.9.2 was used to calculate the minimum sample size for this study, with a 1 − β = 0.8 and an effect size of 0.55, based on the mean ± SD of Body Mass Index (BMI) in a sample of obese individuals attending weight management clinic [33]. The minimum sample required was 52 participants for the single group. Out of 100 questionnaires distributed and collected back, 62 (62%) were considered and included in the analysis, as 28 participants did not complete the assessments, seven dropped out during the initial one-month treatment phase, and three could not be reached for follow-up assessment at three months (Fig. 2).
Procedure
Participants were scheduled for an individual testing session. Diet clinics adopted a weight loss program for 12 weeks throughout which, participants have a decrease of 500–700 kcal regarding to spontaneous food intake corresponding to a daily decrease of energy intake of 25–45% from baseline needs, a method demonstrated to improve adherence to diet [34]. The dietary pattern used was based on the Mediterranean lifestyle, known for its numerous health benefits [35]; it was diversified and composed of fruits and vegetables, legumes, cereals, and olive oil [36]. The distribution of macronutrient followed the recommendations of the Spanish Society of Community Nutrition: 35% fat (< 10% saturated and 20% monounsaturated), 50% carbohydrates, and 15–20% protein [37].
Additionally, participants were instructed and encouraged to engage in moderate to vigorous-intensity physical activity sessions targeting a maximum heart rate of 65–75% at most for 150 min per week, preferably on most days of the week as per international recommendations [38]. For people who could, a specific weight-lifting training program was advised. Weight lifting is a strength training that helps people gain muscles, which speeds up metabolism and burns more fat on the long term. It is recommended for most people and positively associated with weight-loss strategies and programs.
All physiological and psychological measurements in the questionnaire were administered at baseline and after 12 weeks of dieting. During these assessment sessions, lasting 30–40 min each, patients' height, weight, and body composition were recorded.
The Tanita wall-mounted rod stadiometer, long-trusted for its accuracy and reliability, was used to measure the height [39], and the GAIA Plus device (Jawon Medical, South Korea) recorded weight and body composition, particularly body fat and muscle mass. This device uses the bioelectrical impedance analysis (BIA) simple technique involving the passage of a small electrical current through the body to calculate impedance, which is inversely related to total body water. Thus, a person with lower impedance would have bigger muscles and more body water [40]. BIA measurements should be performed in a standardized manner, ideally at the same time of the day for sequential measurements, to avoid possible variability of results [41].
The three dietitians kept personal records for all clients, which included medical history, family history, and food diary and patterns. The dietitians listened to the desires, needs, and capacities of their clients to set a diet target together and taught them to recognize the feelings of hunger and satiety. The weight and body composition of the participants’ was recorded by the dietitian every 15 days. The weight loss was calculated by subtracting the current weight from the previous recorded weight. Waist circumference was measured using a tape meter.
Questionnaire
The questionnaire used during the interview was in Arabic, the native language of Lebanon. The first part assessed the sociodemographic information of the participants (age; gender; marital status; educational level divided into primary (less than 5 years of education), complementary (more than 5 years of education), secondary (more than 9 years of education), and university (more than 12 years of education); monthly income divided into no income, low < 1000 USD, intermediate 1000–2000 USD, and high income > 2000 USD), and other variables, such as a family history of eating disorders, BMI, alcohol, tobacco, and caffeine consumption, the perfect and desired weight, and the Total Physical Activity Index (PAI). BMI was calculated by dividing the weight (in kg) by the height in meters squared (m2). Alcohol, tobacco, and caffeine consumption were categorized into dichotomous variables (yes/no). The ideal and the desired weight were assessed by two open questions “what is the desired weight that you want to reach” and “what is the perfect weight that you want to reach”. The total PAI was calculated by multiplying the intensity, duration, and frequency of daily activity, reported by participants regarding their physical activity during leisure time [42]. In the original study, the PAI was validated against oxygen consumption (VO2) and heart rate (HR) as variables. Regression analysis revealed a strong positive relationship between the PAI score and VO2 and HR [42].
The second part of the questionnaire consisted of the perception of eating habits among participants. The questions were selected from previous articles [43]. Examples of the asked questions were: “Do you take your weight daily?”, “Do you follow a diet to lose weight?”, “Do you exercise to lose weight?”, “Do you take diet pills to lose weight?”, “Do you take laxatives or vomit to lose weight?”, “Do you starve yourself to lose weight?”, and “Are you under pressure from magazines/TV about losing weight?” and “Do you receive comments from your family concerning weight loss?”. A content validity was done by dietitians and researchers where each items was evaluated for content relevance and representativeness.
The final part of the questionnaire included the following scales:
Quality of life short form-12 health survey (SF-12)
The 12-item Short Form Health Survey (SF-12), validated in Lebanon [44], is a Generic Health Rating Scale developed to reproduce the Physical and Mental Component Summary Scores (PCS and MCS, respectively) of a longer survey, the SF-36. Physical and Mental Health Composite Scores (PCS & MCS) are computed using the scores from the twelve questions and range from 0 to 100, where a zero score indicates the lowest level of health and 100 the highest level of health [45]. In this study, Cronbach’s alpha was 0.743.
Body dissatisfaction subscale of the eating disorder inventory-second version (EDI-2)
In the present study, body dissatisfaction score was measured using the Eating Disorder Inventory (EDI-2) subscale [46] that assesses the levels of dissatisfaction with the overall body shape and specific body parts. It consists of nine items scored on a 4-point Likert scale from 0 (sometimes, rarely, never) to 3 (always). The total score was calculated by summing the nine items. Higher scores are indicative of greater body dissatisfaction [46]. In this study, Cronbach’s alpha was 0.792.
The Rosenberg Self-esteem Scale (RSES)
The RSES is a 10-item scale used to assess beliefs and attitudes towards self-esteem. The psychometric properties of the RSES were evaluated by two studies: the first study examined the psychometric properties of the RSES on college students from eight countries and found adequate to high-reliability results for each country [47]. The second study validated the RSES by translating it into 28 languages and administering it to 16,998 participants across 53 countries. it revealed good psychometric properties across different languages and cultures [48]. The answers were graded on a 4-point Likert scale from 1 (strongly disagree) to 4 (strongly agree). The total score was calculated by summing the ten items [49]. Scores below 15 indicated low self-esteem, and those over 15 indicated higher self-esteem. In this study, Cronbach’s alpha was 0.739.
Perceived Stress Scale (PSS)
There are three standard versions of the PSS: the original 14-item form (PSS-14), the PSS-10, and a four-item form. In the original article the PSS-10 demonstrated moderate convergent validity with a good internal consistency (α = 0.78) [50]. In this study, the PSS-10 was used and it was validated in Lebanon [51]. It is a self-report questionnaire used to measure the perception of stress [50]. Ten direct questions scored on a 5-point Likert scale from never (0) to almost always (4) was used to evaluate the levels of experienced stress in the last month [52]. The total score was calculated by summing the ten items, with higher scores indicating higher perceived stress [50]. Scores ranging from 0 to 13 indicate low stress, scores ranging from 14 to 26 indicate moderate stress and scores ranging from 27 to 40 indicate high perceived stress [50]. In this study, the Cronbach alpha was 0.732.
Hamilton Anxiety Rating Scale (HAM-A)
The HAM-A, validated in Lebanon [53], is one of the first rating scales to measure the severity of perceived anxiety symptoms. The Arabic version of the HAM-A showed good validity and adequate internal consistency (Cronbach’s α = 0.921) [53]. It consists of 14 symptom-defined elements, identifying both psychological and somatic symptoms. Each item is scored on a basic numeric scoring of 0 (not present) to 4 (severe). The total score, calculated by summing the 14 items, ranged from 0 to 56, with higher scores indicating higher anxiety [54]. In this study, Cronbach’s alpha was 0.894.
Hamilton Depression Rating Scale (HAM-D)
The HAM-D, validated in Lebanon [55], was used to measure depression. The HAM-D rating scale includes 21 items, with the last four items not counted toward the total score since these symptoms provide clinical information and are either uncommon or do not reflect depression severity. Therefore, the remaining 17 items of the HAM-D are scored and measure depressive symptoms. The HAM-D is categorized into four categories: No depression (lower than 7), mild depression between 8 – 16, moderate between 17 – 23 and severe equal and higher than 24 [56]. Higher scores would indicate higher depression [57]. In this study, Cronbach’s alpha was 0.729.
Statistical analysis
IBM® SPSS® Statistics software version 23 (Armonk, New York 10504-1722 United States) was used for data analysis. The mean percentage of missing data was less than 5.0% of the database; therefore, no values were replaced. A descriptive analysis was done using the counts and percentages for categorical variables and mean and standard deviation for continuous measures. The values for skewness and kurtosis were used to prove normal distribution. As the values of the dependent variables were under the acceptable range − 2 and + 2 [58] we have considered that the data normally distributed (the body dissatisfaction subscale: skewness = 0.46, kurtosis = 1.2; physical and mental quality of life: for PCS: skewness = 0.32, kurtosis = − 1.10, MCS: skewness = 0.26, kurtosis = − 0.93). In addition, the normal probability plots of the dependent variables were analyzed and the results showed a normal distribution. The Student’s t-test was used to compare two means whereas the ANOVA test was used when comparison involved three or more groups. Pearson correlation was used for the linear correlation between continuous variables. For categorical variables, the chi-square and Fisher exact tests were used. The paired sample t-test was used to compare continuous variables before and after the diet. Stepwise linear regressions were conducted, taking the body dissatisfaction and the physical and mental quality of life as dependent variables, respectively. We tested for multicollinearity and no similarities had been found between the independent variables. All the variables that showed a p < 0.1 in the bivariate analysis were considered important variables to be entered in the model in order to eliminate potentially confounding factors as much as possible [59]. A repeated measures ANOVA was conducted to evaluate factors associated with the change in QOL after the intervention. A value of p < 0.05 was considered significant. The internal consistency of the scales was assessed using Cronbach’s alpha.