Standard nutritional care: One frontal meeting with the study's registered dietitian at the clinic, including nutritional and behavioral assessment and recommendations, followed by guidance to to continue follow up in order to support healthy lifestyle.

Grazing will be assessed before and at the end of the 3-month intervention, for both intervention and control group, by using two questions from the grazing questionnaire by lane et al: "Do you graze between meals?" and "would you describe the way you generally eat as unplanned and repetitious (i.e. eating between planned meals and snacks)?", each time regarding the last month. Answering Yes for 1 or 2 of the questions will be considered as grazing behaviour.

Food tolerance will be assessed before and at the end of the 3-month intervention, for both intervention and control group, by asking the patients "regarding the last month, Are there any types of foods or beverages that you cannot eat because of intolerance (suffering from pain or discomfort after eating a small amount)?". This question was based on the validated questionnaire by Suter et al. an answer of yes will indicate food intolerance, the more foods and drinks detailed the worse the intolerance is.

Subjective binge eating habits will be assessed before and at the end of the 3-month intervention, for both intervention and control group. Patients will be asked it they have had episodes of eating subjectively large amounts of food while experiencing a sense of loss of control at least once a week in the last 3 months, according to the DSM-5 definition.

Dietary intake will be assessed before and at the end of the 3-month intervention, for both intervention and control group. Patients will be asked to fill food diaries for 3 days consisting of 2 week days and 1 weekend day. Daily average intake in calories will be calculated based based on the "Nutratio" software.

Dietary intake will also be assessed before the intervention, for both intervention and control group, by a 24-hour dietary recall. To reduce information bias, patients will be shown examples of standard cups, spoons, teaspoons and foods using the Israeli food atlas and visual measuring tools. Daily average intake in calories will be calculated based on the "Nutratio" software.

Dietary intake will also be assessed before the intervention, for both intervention and control group, by a FFQ. To reduce information bias, patients will be shown examples of standard cups, spoons, teaspoons and foods using the Israeli food atlas and visual measuring tools. Daily average intake in calories will be calculated based on the "Nutratio" software.

Food environment's impact on eating behaviors will be assessed before and at the end of the 3-month intervention, for both intervention and control group, by a validated questionnaire "Power of food scale". Each of the 15 questions gets a score between 0 (Do not agree at all) to 5 (strongly agree). The scores are summed up between 0-75, a higher score indicating higher sensitivity to food environment.

Patients will be asked at baseline and at the end of the intervention program about their physical activity regimen including type, duration of each session and times per week. In addition, self-reported physical activity levels will be collected via phone calls at 3 and 6 months after the end of the intervention program. Data of minutes of physical activity per week will be compared between groups.

Strength of the upper extremities will be measured before and at the end of the 3-month intervention program, for both intervention and control group, by a digital hand dynamometer (Jamar plus digital). Measurements will be taken three times for the dominant hand with a break of 15 seconds between each measurement, and an average will be calculated. Results in kilograms will be compared to manufacturer's normal values by age and gender.

To assess lower extremity strength, the 5 times sit and stand test will be used before and at the end of the 3-month intervention program, for both intervention and control group. Time in seconds to complete the test will be measured, faster time indicating better lower extremity strength.

Sleeping quality will be assessed before and at the end of the 3-month intervention for both intervention and control group, each time regarding the last month, by a validated questionnaire - The Pittsburgh Sleep Quality Index (PSQI).The PSQI includes 19 questions grouped into components, each on a 0-3 point scale. Scores of >5 indicate subjective insomnia. Moreover, 3 and 6 months after the end of the intervention complement, patients from both intervention and control group will be asked by phone call about their average sleeping hours on weekdays and weekends.

Three and 6 months after the end of the intervention complement, patients from both intervention and control group will be asked by phone call about their average sleeping hours on weekdays and weekends.

Happiness and subjective wellbeing will be assessed before and at the end of the 3-month intervention for both intervention and control group using a structured questionnaire by Sherman and Shavit. The questions include patients subjective well-being by asking them to assess their present life on a Likert-type scale from 0 representing "worst possible life" to 10 representing "best possible life".

Self-reported weight in kilograms at 3 and 6 months after the intervention complement will be asked by phone call for both intervention and control group.

Self-reported number of follow up meetings at 3 and 6 months after the intervention complement will be asked for both intervention and control group. Patients will be asked how many meetings they had with a registered dietitian, a psychologist/social worker, a surgeon and a personal trainer.

Self-reported supplementation usage at 3 and 6 months after the intervention complement will be asked for both intervention and control group regarding the last month.