The aim of this randomized controlled study determine the efficacy of calorie restriction intermittent fasting diet in metabolic parameters and weight management among metabolic syndromes adults. It was done on metabolic syndrome patients, aged 18-65 years at an academic institution in Istanbul,Turkey. Subjects were divided into two groups; IER (Intermittent Energy Restriction-intervention group, calori restriction of 300-500kcal/d combined with 16:8 model Intermittent Fasting) and CER (Countinous Energy Restriction- control group continous restriction of 300-500kcal/d). Assessment was ascertained at baseline and 12 weeks. Blood samples were analyzed for lipid profile, fasting plasma glucose, ınsulin, HOMA-IR. Blood pressure and body composition were evaluated.

Aim The aim of this study; determine the efficacy of calorie restriction intermittent fasting diet in metabolic parameters and weight management among metabolic syndromes adults.

Subjects Participants who referred by clinician, as medical doctors after physical assesment selected in this study were recruited among patients with metabolic syndrome referring to the diet clinic local in Turkey. The criteria of inclusion were metabolic syndrome patients, aged 18-65 years had body mass index (BMI) ≥27 kg/m2 with no history of mental or physical disabilities.Subjects should also not be practicing Muslim Ramadan fasting or had changed their dietary pattern 12 weeks before the study. Eligible subjects were approached to participate. Only those who agreed to participate were explained of all the information pertaining to this study and were consented. This study was approved by Istanbul Medipol University Ethics Committee.

Study design The aim of A randomized controlled study was carried out to determine the efficacy of calorie restriction intermittent fasting diet in metabolic parameters and weight management among metabolic syndromes adults. Subjects were randomly assigned into two groups; intervention IER (Intermittent Energy Restriction) and control CER (Continuous Energy Restriction). Randomization, first participant assigned IER group an each eligible participant was randomly assigned to either CER group or IER group. Those who were assigned to two groups needed to adhere dietary regime, with a reduction of 300-500kcal/d from the habitual energy intake for 12 weeks intervention period. Diet menus were prepared taking into account the individual characteristics. IER participants abide by intermittent fasting which time restricted 16:8 model diet. During 16 hours; such as at 04.00 pm- 08.00 am or 05.00 pm - 09.00 am or 07.00 pm - 11.00 am fasting hours, no food and calorie drink. But participants in fasting hours can drink water, sugar free tea and mineral water, coffee without sauce. On the other 8 hours, need to adhere energy restriction diet. Subjects were also provided with seven-day food menu guidelines. Those who were assigned to two groups need to maintain their present lifestyle. Analysis was carried out at two time points: baseline and week 12. In order to ensure good compliance, subjects were contacted once a week via telephone calls. Food diaries and were fasting log book presumed to the participants during each assessment meeting. Subjects were given detailed instruction verbally and a reference guide on how to fill up the food diaries and fasting log. Individual and group counseling were provided before and during the intervention period.

Body composition, Blood Pressure, Biochemical markers Height was measured using SECA-213 portable stadiometer (SECA, Hamburg, Germany). Body composition was measured using TANITA SC-330, body composition analyzer (TANITA Corp. Tokyo, Japan). All measurements were made in the morning at participants fasted state. This instrument was calibrated each time before measurement. Data from this instrument including body weight, BMI, body fat percentage, fat mass, fat free mass and total body water.

Body mass index (BMI) was calculated as; BMI [kg/m2]= Weight[kg] / (Height[m] x Height[m]) Waist circumference was measured by the same dietician with the help of a standard unstretched tape measure. Blood pressure and heart rate were measured using an automatic oscillometric device (Omron M2 Basic, Japanese) after participants had rested in a seated position for 5 min. A blood sample was drawn at baseline and after 12 weeks. Insulin resistance was estimated with the homeostasis model assessment (HOMA-IR) and calculated as; HOMA-IR= (Fasting plasma glucose [mg/dL] x Serum insulin [IU/L]) / 405

Biochemical markers blood lipids, fasting plasma glucose and Haemoglobin A1c (HbA1c) were performed with standard methods. Serum concentrations of insulin were measured by immunonephelometric methods. Adverse events were monitored by standardized questionnaires, diary and at the last study visit by interview.

Inclusion Criteria:

• Being between the ages of 18-65
• Body mass index to be 27 and above
• Clinical diagnosis of metabolic syndrome according to the criteria of IDF 2005 or NCP ATP III.

Exclusion Criteria:

• Being in the pre-menopausal or menopause
• Following a special diet (such as Celiac, Type 1 diabetes)
• Using a special nutritional supplement (omega 3, probiotic, vitamin-mineral, teff seed etc.)
• Those who do not comply with the diet, pregnant, being lactating
• Doing heavy physical activity or working in a heavy job
• Presence of liver, kidney or immune deficiency
• Conditions that will seriously affect weight management such as having bariatric surgery
• Determined to have had an unintentional sudden weight loss of more than 5% in the last three months
• Not be practicing Muslim Ramadan fasting or had changed their dietary pattern 12 weeks before the study