Science & Health

Sobre o Jejum

Fasting has been part of religious and cultural traditions for centuries. In recent years, science has been studying the effects of fasting and intermittent fasting on the body, with notable findings on metabolism, cardiovascular health, brain function, and cellular renewal.

Fasting and Metabolism

Current studies show that fasting and similar dietary patterns improve metabolic health. Reviews and meta-analyses published in journals such as The Lancet and Frontiers in Nutrition (2024) report that intermittent fasting improves insulin sensitivity, helps control blood sugar, and leads to favourable changes in lipid profiles.

Dawn-to-sunset fasting, including Ramadan fasting, has been studied in healthy adults; significant improvements in triglycerides, LDL cholesterol, and blood pressure have been observed.

Autophagy and Cellular Renewal

Autophagy is the cell’s natural “clean-up” process: it breaks down and reuses its own components. Nutrient restriction and fasting trigger autophagy, helping clear damaged proteins and organelles and supporting more efficient cell function.

Research indicates that during fasting, signalling pathways such as AMPK and SIRT1 are activated, supporting fatty acid oxidation and mitochondrial function.

Heart and Vascular Health

Systematic reviews and meta-analyses on Ramadan fasting point to beneficial effects on endothelial function and cardiovascular risk factors. In healthy adults who fast from dawn to sunset for about four weeks, significant changes in cardiometabolic parameters have been reported.

For people with existing heart disease, the decision to fast should be made with a doctor.

Weight Management and Energy Balance

Fasting and caloric restriction can provide benefits similar to conventional diets in the management of obesity and related chronic diseases. Research shows that the fasting window regulates fatty acid metabolism and affects fat burning and energy use.

Balanced iftar and suhoor meals are important for sustainable weight management.

Brain and Neurological Health

Some studies suggest that intermittent fasting may have neuroprotective effects and could increase resilience against neurodegenerative conditions such as Alzheimer’s and Parkinson’s. Autophagy and reduced oxidative stress may play a role.

Researchers also stress that larger, long-term randomised controlled trials are needed in this area.

Ramadan Fasting and Scientific Research

Ramadan is the month in which Muslims observe the obligatory fast. In the scientific literature, this practice is often referred to as “dawn-to-sunset intermittent fasting”: refraining from food and drink during daylight for 29–30 days.

Meta-analyses have synthesised many studies on the impact of Ramadan fasting on metabolic syndrome components and cardiovascular risk factors.

Points to Consider

Although research indicates that fasting can have many benefits for healthy individuals, pregnant or breastfeeding women, people with diabetes, kidney or heart disease, and those on regular medication should always consult their doctor.

Clinical recommendations exist specifically for people with cardiovascular disease regarding Ramadan fasting; individual assessment is important.

Conclusion

Fasting is a practice that has been studied both from religious and scientific perspectives. Current research shows positive effects on metabolism, cardiovascular health, cellular renewal (autophagy), and weight management.

For healthy fasting, balanced nutrition at iftar and suhoor, adequate fluid intake, and consideration of personal health are essential.

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