Intermittent Fasting: A Nutritionist's View

Intermittent fasting has gained a lot of attention in recent years as a popular approach to weight management and overall health. Intermittent fasting involves alternating periods of fasting and eating, with various fasting and eating windows, e.g. 8 hours of eating and 16 hours of fasting per 24 hour window. Let’s delve into the pros and cons of intermittent fasting to help you make an informed decision about whether it is right for you.

Intermittent fasting and weight loss 

The concept of weight loss through fasting is based on the idea that when we break a prolonged fast, we tend to consume less food than what we would have eaten if we hadn't fasted. This creates an energy (calorie) deficit, leading to weight loss. However, if no other lifestyle or dietary changes have been created, when regular fasting is stopped, it is likely to result in weight gain. 

Numerous studies have investigated the effectiveness of intermittent fasting compared to traditional calorie-restricted diets in promoting weight loss. While most of these studies have found only slight differences in weight loss between the two approaches, it's important to note that individual outcomes may vary. So, it may work for some, but not for others.  When it comes to weight loss goals, intermittent fasting doesn't appear to be superior to other types of calorie-restricted diets.

Potential Benefits of Fasting

After long term fasting, studies vary from 14-48 hours, autophagy is triggered. Autophagy is where the body clears out damaged cells and cellular waste. This cellular repair process may have anti-aging and disease-fighting benefits. However, more research is needed to fully understand the extent of these effects in humans.

Cons of Intermittent Fasting

Intermittent fasting may not be suitable for everyone, as it can disrupt usual eating patterns. For individuals who have a history of disordered eating, such as restrictive eating or binge eating, intermittent fasting may perpetuate or exacerbate these behaviours. It is essential to approach fasting with caution and consult a healthcare professional if you have a complicated relationship with food.

Restricting the eating window can make it challenging to consume an adequate amount of essential nutrients within a limited timeframe. It may require careful meal planning to ensure adequate intake of vitamins, minerals, and macronutrients. This makes it especially important to eat nutrient dense whole foods whilst undertaking an intermittent fasting plan. 

During fasting, some people may experience increased irritability, low energy levels, or difficulty concentrating. It's essential to listen to your body and discontinue intermittent fasting if it negatively impacts your well-being.

Intermittent fasting & Women’s Health 

Many of the research conducted on fasting has been done with men, so unfortunately it may not be the best option for women, especially if you are trying to conceive or struggling with a reproductive condition or hormonal imbalance. Some women may experience changes in their menstrual cycle when practising intermittent fasting. This could manifest as irregular periods, missed periods, or changes in the duration or intensity of menstrual bleeding. Hormonal fluctuations and disruptions in energy balance, particularly in cases of extreme calorie restriction, may contribute to these changes. 

Additionally, intermittent fasting, particularly when combined with other lifestyle stressors, can potentially increase stress hormone levels such as cortisol. Elevated cortisol levels may interfere with the delicate hormonal balance in women and have implications for reproductive health and fertility.

The final word

Ultimately, the decision to try intermittent fasting should be based on your individual goals, and health considerations. If you are considering intermittent fasting, it is important to consult with a healthcare professional, such as a nutritionist, who can guide you based on your unique circumstances and help you establish a safe and sustainable approach.