Can cancer patients fast safely during Ramadan?

The holy month of Ramadan has begun. Fasting in Ramadan is one of the five pillars (Arkan) of Islam. The Holy Quran states: “Whoever among you witnesses the month must fast, but whoever is ill or on a journey should make up the missed days later” (Surah Al-Baqarah 2:185). It also reminds believers that fasting is beneficial for those who are not exempt (2:184). At the same time, Islam clearly forbids fasting if it may harm health. Despite medical exemptions, many patients still wish to fast to share the spiritual experience with their families. The daily fasting duration also varies by season and geography.

Muslims number nearly 2 billion worldwide (about one-quarter of the global population). Therefore, a significant proportion of the roughly 20 million cancer cases diagnosed annually (GLOBOCAN 2022) occur in Muslim populations. With major advances in cancer care over the past two decades—including targeted oral therapies and immunotherapy—survival and cure rates have improved markedly, and many cancers now behave like chronic conditions. As more patients live longer and healthier lives, clinicians are increasingly being asked an important question: Can cancer patients fast safely during Ramadan?

Oncologists at the beginning of Ramadan do often face the questions “Doctor, can I fast?” Or Doctor if I fast, how to continue with treatment ? etc.etc. Most Oncologists base their reply on personal experiences and judgment as the scientific evidence is lacking to a large extent about the fasting in cancer patients. Many Oncologists may feel guilty if they advise patients against fasting and may prefer to be neutral and just say “Look, fast if you can,” and most of the Oncologists generally have a negative attitude towards fasting. However, there are no guidelines or standardized protocols that can help Oncologists to properly address the issue of patients with cancer and fasting in Ramadan and correctly advise them. Very less is known in medical literature about fasting and cancer care. The quality of life and compliance to anti-cancer treatment is of utmost concern for both the treating Oncologist and the patient. It is a common saying that religion promotes healthy lifestyles. However, the relationship between religion and cancer has been often overlooked or poorly addressed from a scientific point of view especially in terms of physiology during fasting in patients suffering from cancer. There is well documented scientific evidence that people who do not consume tobacco, alcohol or pork due to religious obligations have lower cancer related morbidity rates from many cancers than the general population. It is known that fasting induces changes in genome organisation, proteins expression, chromatin remodelling, and metabolic pathways and modulating for example, glucose, insulin like growth factor (IGF), other related enzymes and proteins and may increase the effectiveness of chemotherapy. Fasting could have a positive impact on drug pharmacokinetics and could contribute to reduce its side effects, improve the chemotherapeutic index, and overcome partially the issue of drug resistance. Fasting has a beneficial impact on the renewal of stem cells and on the immune system, especially on natural killer cells, as well as on the oxidant system, thus enabling cancer growth control. The impact of fasting has been assessed on different anti-cancer drugs and the effects of fasting on tumours have been assessed both on neo-adjuvant and adjuvant chemotherapy. Fasting seems to sensitize tumour cells and increase the outcome of anti-cancer drugs. We know that avoiding starchy and sugary foods and caloric restriction has a role in controlling cancer and we know that obesity is a risk factor for various cancers like breast, uterus, prostate to name a few.

Diagnosis of cancer is always difficult to cope with. The level of spirituality and religiosity plays a major role in supporting the patients during treatment and can influence the clinical outcome. The communication between the patient and the Oncologist for the purpose of Ramadan fasting should be open and honest. At times the situation is rather delicate and the Oncologist, if not culturally competent or sensitive, could be left with dilemmas because of the cultural and religious beliefs and attitudes of the patient. Oncologists should carefully assess the health conditions of patients and discourage them to fast if;

Patient is very old

Has widespread cancer

Have aggressive forms of cancer

Are weak and frail

Poor in nutrition

Have associated illnesses like diabetes

Need round the clock fluids and other supportive treatment for cure of cancer or

Have history of non-compliance to drugs and dietary advices

On the contrary, patients with a strong motivation to fast should be encouraged, in that spirituality/religiosity plays a major role in cancer. Many cancer patients feels more active being involved in the religious activities, and less depressed and isolated. There is solid scientific evidence that fasting activates certain neuroendocrine pathways leading to the release of neurotropic factors, which can enhance the mood and relieve the pain in patients suffering from cancer. Patients who decided to go on fasting after the diagnosis of cancer and who should be encouraged are those;

With good performance status and body strength

Young cancer patients,

Those without any associated illnesses like diabetes

Having early stage cancer

Those being treated with single agent anticancer drug

Patients on oral chemotherapeutic agents and

Disease free patients on follow-up.

Oncologists are concerned about the possibility of fasting and its negative impact on patients receiving active treatment for cancer and the compliance to drugs. The management of patients suffering from cancer and who is willing to fast is very complex and should involve a multidisciplinary team, made up of an Oncologist and other supportive staff who should be aware of the importance of cultural and spiritual beliefs in medicine, and particularly in Oncology practice.

Important factors that hesitates the Oncologist and the patients to stop fasting are fear that fasting state would lead to a decrease in the actual performance, preventing the administration of anti-cancer drugs and leading to the disease progression. When discussing fasting with the patient, Oncologists can adopt the safe trial technique where they allow the patient to fast, but with instructions as to when they should stop (e.g., when there is severe weakness, vomiting, diarrhoea, or inadequate oral intake which may be harmful). Close contact with the treating Oncologist is of utmost importance. If the advice is “fast if you can,” then this should be under medical supervision. For example, giving supplementary IV fluids during Iftaar time or modifying the treatment schedule so that the drugs are given between sunset and dawn (Iftaar and Sehri) might be of help in some situations. The issue of fasting in cancer patients should be discussed among Oncologists and the knowledgeable religious authorities to avoid conflicting advice that can harm cancer patients. Oncologists need to be aware of the religious aspects of fasting. An ideal practice would involve the patient, treating Oncologist and the religious scholar in the decision making.

Dr Mir Mohmad Hussain MD,DM,PDF is Assistant Professor Medical Oncology, SKIMS