Letter to the Editor - Islamic fasting: cardiovascular disease perspective

Naz et al. [1] provide a comprehensive review of the effects of Ramadan fasting (RF) on different cardiovascular (CV) diseases (CVDs). The review focuses on obtaining a consensus on the management of CVDs and the risk of these pathologies during RF. The authors [1] propose a useful pre-Ramadan checklist for patients with CVDs and also introduce a CVDs riskstratification pyramid for clinicians. Research in fasting has gained importance, due to evidence of benefits in several chronic diseases [2]. In the holy month of Ramadan, millions of Muslims fast from dawn to sunset during 12–20 h [3], and mainly consume two meals, one before dawn ‘suhoor’ and one after sunset ‘iftar.’ As the authors mentioned, recommendations for patients with CVDs during RF are deficient [1]. Therefore, considering that CVDs are the leading cause of death worldwide [4], it is necessary to obtain consensus and specific nutritional recommendations in order to prevent worsening of CV risk factors during RF. The article [1] considers studies that specifically show benefits of RF on some lipid parameters. However, this possible positive impact cannot be generalized, because of the observational nature of many studies. Also, some reviews show conflicting outcomes regarding lipid parameters [5,6]. In addition, systematic reviews that have shown benefits, have excluded patients with conditions, such as metabolic syndrome [7]. Variable results are plausible because the lipid profile is affected by several biological and lifestyle factors. For example, some studies fail to account for potential confounders such as smoking and physical activity. Besides, it is important to consider baseline parameters before the RF, and the type and quantity of food ingested during the RF ‘eating window.’ Indeed, it is known that there is a greater consumption of simple carbohydrates and sugar during feeding time [6,8]. According to tradition, sweets, food with honey, and soft drinks are consumed [9]. Furthermore, a study in 2021 involving overweight and obese Muslim women, dietary records showed the need to promote nutritional health education to ensure a healthy RF [10]. This is worrying, due to the known detrimental effects of frequent consumption of refined carbohydrate-rich foods on circulating triglycerides [11]. Moreover, recent reviews also suggest a possible effect on worsening low density lipoprotein (LDL) cholesterol [12]. According to this background, and considering that one of the important behavioral risk factors for heart disease and stroke is an unhealthy diet [4], it is necessary to provide adequate advice about nutrition, if patients with CVDs fast for the full month of Ramadan. To our knowledge, there are no guidelines for nutritional recommendations for patients with CVDs or CV risk factors during RF, as there is for diabetes, such as the Ramadan Nutritional Plan [13]. Therefore, we suggest that the preRamadan checklist and clinician advice, might include specific nutritional recommendations for patients with CVDs that could allow better food selection during RF, taking into account culture and food availability. We suggest a preRamadan assessment where individuals with CVDs or CV risk factors could seek individualized nutrition advice. Within the specific nutritional recommendations to include during RF, it would be useful to focus on cereals and whole grain consumption. Also, it would be relevant to promote meals that include legumes or meat accompanied by vegetables. In relation to proteins, it is advisable to prefer lean and oily fish, or poultry without its skin. Concerning fruits, it is important to promote the choice of fresh fruits and dried fruit; canned fruit or fruit juice, only in moderation. Additionally, the consumption of natural nuts and seeds could be promoted. Also, a moderate consumption of honey, dates or sweet preparations containing these foods as ingredients, if any, as well as avoiding the consumption of ultra-processed food, trans fat, hard margarines, butter, sweets, and soft drinks [11]. By the selection of this type of food, there could be a beneficial impact on CV risk factors, including lipids [11]. We agree with the authors [1] that most of the studies that evaluate lipid profile changes do not report energy, and macroor micronutrient consumption during RF. Also, the literature on food intake in RF is scarce [9]. Therefore, further studies comparing the composition of the diet before and after RF in patients with CVDs or CV risk factors should provide a broader understanding of how RF affects the lipid profile. Also, clinicians may then be able to provide personalized nutritional advice to these patients during RF. However, given the current evidence, it may be beneficial to reinforce general advice regarding food selection that can contribute to improving the lipid profile, or preventing it from worsening.