Intermittent Fasting – Is it really worth the hype?
Prepping overnight oats for breakfast and eating lunch at noon are bygones; suddenly, everyone is scheduling dinner before 6 pm like senior citizens and ordering non-alcoholic, zero-cal drinks. Yes, we’re talking about intermittent fasting, the latest health trend that everyone is bandwagoning. While intermittent fasting (IF) has existed for centuries, it’s recently become a popular lifestyle choice for health-conscious eaters around the globe.
Intermittent fasting is a dietary pattern that involves caloric restriction by limiting eating to certain intervals of the day.
People fast for many reasons, but historically, fasting has been a cultural phenomenon for centuries and remains a religious practice within Islamic, Judaism and Christian faiths. Especially this time of year – March and April are usually sacred months for many Abrahamic faiths, which traditionally fast during this period to strengthen their connection with God. Apart from other benefits – which we’ll get into later– some have reported that intermittent fasting allows a ‘heightened mental state’ and improved cognitive functioning.
For Muslims, the holy month of Ramadan serves as a time of spiritual reflection where observers fast for approximately 30 days until the sighting of the new first moon. During this period, devotees abstain from eating and drinking water from dusk and only break their daily fasting period at dawn. This is repeated until Eid-ul-Fitr, as determined by the lunar calendar. Jewish communities have Yom Kippur and Christians have Lent – these are just three examples of religious faiths that perform fasting.
So, if fasting has been around for so long, when did intermittent fasting suddenly become so popular? While it’s existed for yonks, the diet approach became radicalised in 2012, after Dr. Michael Mosley’s TV documentary, Eat Fast, Live Longer aired; his book, The FastDiet, also sparked international interest. Similarly, when journalist, Kate Harrison’s book The 5:2 Diet was released, the diet amassed quite the following and people started skipping breakfast.
What is intermittent fasting & how does it work…?
Intermittent fasting is a dietary pattern that involves caloric restriction by limiting eating to certain intervals of the day, hence ‘intermittent fasting’. T has undoubtedly gained popularity as a weight loss method – this remains controversial as most studies involve rats and not human subjects, it also goes without mentioning that both have significantly different digestive systems and body fat percentages. But how does intermittent fasting work, and does it actually work?
Part of why intermittent fasting has become a preference for many is ‘flexibility’. You could technically eat anything you want and curate your diet around the clock or your daily routine. Individuals may opt to skip breakfast, but several standard fasting methods exist:
Time-restricted eating involves daily fasting. This is usually done for 12 hours or longer. Many follow the 16/8 method, where the fasting period is 16 hours, leaving an 8-hour window to eat. Others prefer the 14/10 method, which is similar but with different hours.
One Meal A Day (OMAD) is also an example of time-restricted eating, but involves eating only one meal a day, as the name suggests. People usually follow a 22:2 or 23:1 method, meaning that they fast for either 22 or 23 hours and can eat within a 1 or 2-hour window.
The 5:2 diet involves fasting for 2 consecutive or alternate days per week; people eat normally for the remaining 5 days of the week – participants can select days according to their routine. For the two days of fasting, food intake is restricted to 500-600 calories per day. While it seems rigid, it’s regarded as a more ‘practical’ approach compared to tracking calories every day of the week; checking a wristwatch is less complicated than racking up math calculations in one’s brain for ‘what you’re allowed to eat’.
The Eat Stop Eat method involves a full-day fast (24 hours) at least once or twice per week, similar to the 5:2 diet.
Alternate Day Fasting involves fasting on alternate days. People typically fast for one day and resume regular eating the following day, this is repeated. The number of fasting days could vary for individuals adopting this method.
The Warrior Diet is perhaps one of the more ‘flexible’ options compared to the fasting methods above. It involves eating raw fruits and vegetables throughout the day and individuals eat one large meal portion closer to supper.
As mentioned, people fast for various reasons, but to reap weight loss benefits, some either count calories or monitor what they eat as opposed to how much they eat. Additionally, people often couple fasting methods with keto, Banting or Mediterranean-style diets, as well as high-intensity training or other exercise regimens. Intermittent fasting sounds like a 9-5 job, but what if you don’t want to lose weight – are there any other benefits?
Pros & cons of intermittent fasting
During non-restrictive eating, the body typically sources energy by burning glucose from carbohydrates, but when fasting, the body burns fat as fuel which can lead to weight loss.
Apart from weight management, IF is believed to assist with insulin sensitivity and improved metabolism by restricting caloric intake, which could result in decreased appetite. Furthermore, this lifestyle is said to result in improved sleep, cardiovascular health and inflammation for diseases like Alzheimer’s, arthritis, asthma, eczema and psoriasis and improving other associated morbidities – potentially having positive impacts on longevity.
Another study found that intermittent fasting could bolster cellular responses and reduce oxidative damage and inflammation, while improving energy metabolism and cell protection.
Sure, the benefits appear to outweigh the negative impacts, but there are also contrasting opinions about intermittent fasting. Although some chronic dieters have sung the praises of intermittent fasting, it could prove a nonsustainable long-term diet plan for many.
While IF might help people curb midnight snacking or practise ‘mindful eating’, it could be a counterintuitive and harmful approach to weight management for those with eating disorders, potentially resulting in binge eating and bulimic pathology. Suppressing internal hunger cues could create hormonal imbalances for at-risk groups like diabetics, causing dangerously low blood sugar levels. When fasting for extended periods, the metabolic rate could decrease and the body may end up storing fat – a process called ‘ketosis’.
Tips for intermittent fasting
Thankfully, some scientific research has reported the benefits of intermittent fasting and its effects on associated physiological diseases, but compelling evidence for its metabolic benefits (for human subjects) has yet to be unearthed.
Here are some general tips and takeaways for those fasting intermittently:
- Stay hydrated – consume enough water throughout the day.
- Fasting for extended periods could cause the body to store fat instead of burning it.
- Starvation is not the same as intermittent fasting, don’t push your limits by fasting for over 24 hours; this can be dangerous for your metabolism and well-being.
- Try to limit your sugar intake when consuming coffee/tea. You might overcompensate for hunger with countless cups of coffee/ tea. PSA: Coffee is not a meal replacement.
- Honour your cravings, cheat or feasting days exist for a reason. Listen to your hunger cues – your body will thank you.
If you are curious about intermittent fasting, it’s always important to first discuss it with a healthcare professional. Restrictive eating might not work as a long-term solution for weight control. It’s urged that people taking scheduled medication, those with eating disorders, diabetics and pregnant/breastfeeding persons, should avoid it or consult a registered dietician before trying this dietary approach.
Read more about whether Breakfast Is Still the Most Important Meal of the Day and more on Debunking Diets: The Pros & Cons of Lifestyle & Popular Diets.
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