IRCT20170211032494N4 IRCT 2023-08-15 Tehran University of Medical Sciences Investigating the tolerability of a diet containing CAPRIDIN in patients with rectal cancer Investigating the tolerability of the diet containing CAPRIDIN in patients with rectal cancer undergoing chemoradiotherapy 2023-08-23 anticipated 20 Complete https://irct.ir/trial/70747 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Supportive, Randomization description: "Random Allocation V.2" software is used for randomization. This software can be downloaded from the following link: https://random-allocation-software.software.informer.com Patients will be allocated in two intervention and control groups in equal numbers. For randomization, the block randomization method was used, which defines blocks of four, and the order of assigning houses to each group is based on random numbers, Blinding description: Patients and their companions, all the people who are involved in patient registration, doctors, nurses and anyone who is in contact with the patient in the process of treatment and care, and the research team are all kept blind to the prescription and consumption of capridin or placebo. The order of the patient's entry is recorded on the envelopes with the patient's code. Codes are also recorded on bottles containing capridin. After the patient has been examined by the doctor in terms of the criteria for entering the study, according to the order of referral, the desired envelope is opened and the code related to the intervention is determined. Based on the code, the bottle of the same code (capridine or placebo) is given to the patient. In this way, the patient is unaware that he is receiving capridine or a placebo. 1-2 Rectal cancer, Ketogenic regimen. Intervention 1: Patients who take 30 cc of CAPRIDIN fasting on average for 6 weeks in addition to the standard rectal cancer treatment. Capridin is a product of HealthWeX (Canada) that contains medium chain fatty acids. These compounds are used in ketogenic diets and induce ketogenesis. Treatments based on ketogenesis in the control of epilepsy are among the approved treatments for this disease. Intervention 2: Patients who take 30 cc of placebo daily on an average for 6 weeks in addition to the standard rectal cancer treatment. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is "No more information has not been provided yet"