Intermittent fasting benefits risks and practical tips

[WORLD] Trying to shed some extra pounds? You may have been encouraged to try intermittent fasting (IF), an eating regimen that alternates between periods of eating and fasting. According to health experts, IF not only supports weight management but also offers benefits for gut health and overall metabolic function.

Recent findings have also drawn attention to IF’s role in cellular maintenance processes, such as autophagy—a mechanism through which the body clears out damaged cells and regenerates healthier ones. This natural detox process is believed to contribute to slower aging and reduced inflammation, further establishing intermittent fasting as a comprehensive wellness strategy.

Consultant in gastroenterology and hepatology, Dr Deborah Chew Chia Hsin, explained that the metabolic shifts triggered during fasting are fundamental to its effectiveness.

“During fasting, the body transitions from using glucose to entering ketogenesis, where it burns free fatty acids for energy. This allows the digestive system to rest and helps maintain metabolic balance,” she told. Dr Chew added that IF also enhances insulin sensitivity, which can help lower the risk of developing type-2 diabetes.

Beyond its impact on metabolism, emerging research suggests that intermittent fasting may influence the diversity of gut microbiota—supporting the growth of beneficial bacteria linked to stronger immunity and improved mental well-being. A 2022 review in Nature pointed to the potential of fasting cycles to reshape gut microbial communities, with implications for managing conditions such as irritable bowel syndrome (IBS) and depression.

There is also evidence suggesting IF can stabilize blood pressure and improve lipid profiles—lowering triglycerides and LDL (bad) cholesterol while boosting HDL (good) cholesterol—thus supporting cardiovascular health.

“There are various fasting strategies to consider,” Dr Chew said. “The 16:8 method involves eating during an eight-hour window and fasting for the remaining 16 hours. Another approach is the 5:2 method, which limits calorie intake drastically for two days per week.”

Intermittent fasting may also benefit brain health. A 2019 study published in the New England Journal of Medicine found improvements in memory and cognitive performance. Additionally, research in animals has linked IF to lower rates of tumor recurrence.

However, experts caution that individual responses to intermittent fasting can differ significantly. Variables such as genetic makeup, metabolic condition, and sleep quality can all influence how well someone adapts to the regimen. For example, a 2023 study in the Journal of Nutrition found that participants with poor sleep patterns gained fewer metabolic advantages from IF compared to those with consistent rest, highlighting the need for a holistic approach.

Dr Chew stressed that IF is not appropriate for everyone, particularly individuals with type-1 diabetes who rely on insulin, as they may face a risk of hypoglycaemia—a dangerous drop in blood sugar.

“Type-2 diabetes patients on oral medication should also proceed with caution. Early warning signs of low blood sugar, such as sweating or confusion, must be taken seriously to avoid complications,” she warned.

People with gastric problems or peptic ulcers are similarly advised to consult a healthcare provider before starting IF, as prolonged fasting could exacerbate stomach acid production and worsen symptoms.

Meanwhile, dietitian and senior lecturer Dr Shanthi Krishnasamy noted that poor dietary choices during eating periods can undermine the benefits of intermittent fasting.

“Some assume IF guarantees weight loss, but if meals are high in calories, sugars, and fats with little nutritional value, the intended health gains won’t be realised,” she said.

She also emphasized the importance of staying hydrated during fasting hours. “Water, herbal teas, and fluids rich in electrolytes are essential to prevent dehydration—especially in tropical climates like Malaysia. Neglecting hydration can lead to fatigue and headaches, which may discourage people from continuing IF,” Dr Shanthi explained.

Even with limited eating windows, she reiterated that maintaining a well-balanced and nutrient-rich diet is crucial. Addressing the challenge of observing IF during festive periods, particularly when open houses and food-centric gatherings are common, Dr Shanthi suggested that fasting should be adapted, not forced.

“Festive seasons can make fasting difficult due to the abundance of food and social expectations,” she said. “That’s why flexibility is key—people might consider alternate-day fasting or selecting specific days to fast.”

For festive meals, she recommended starting with lighter options like salads and water before moving on to main dishes. “If you want dessert, just a couple of spoonfuls are enough to enjoy the flavor without overindulging,” she advised.