NUTRITION
per day( modified alternate day fasting), while on feast days individuals can eat freely, without any restrictions,” notes Dr Wolberg.
2. 5:2 DIET
Then there is the 5:2 diet which is a modified version of ADF.“ It involves two fast days( 500-1 000kcal per day) and five feast days per week,” says Dr Wolberg,
3. TIME RESTRICTED EATING( TRE)
And finally, probably the most popular, time restricted eating. As opposed to ADF and the 5:2 diet, TRE requires individuals to fast for a specific period of time every day.“ Time restricted eating limits the eating window to a specified number of hours each day, typically four to eight hours. The remaining hours of the day are fasting, with water or zero calorie drinks.”
HOW DOES IF WORK?
IF isn’ t just about restricting calories, there’ s more to it than that.“ The main concept behind intermittent fasting is that by restricting food, our bodies will switch from using glucose and depleting our glucose stores, our most direct fuel, to using fat stores in adipose tissue,” explains Dr Wolberg.
IF has also been associated with a healthy microbiota profile, which is important because research tells us that your gut is the epicentre of your overall health and wellness.
“ Studies have shown that using intermittent energy restriction as a dietary tool results in an increase of the beneficial strains( for example, Lactobacillus and Akkermansia),” adds Dr Wolberg. She warns though that more clinical trials are necessary to observe the long-term effects on the gut microbiota.
But, if true, it could help not just with inflammation and metabolic health but with your mental health as well.“ The microbiota in the gut is in flux throughout the day in response to circadian and hormonal fluctuation as well as dietary intake,” explains Dr Wolberg.“ It has been hypothesised that these microbiotas respond to feeding times. A western diet eating close to or during the rest period, decreases the microbiota fluctuations, these results in a less diverse gut microbiome.”
And, as you may expect, IF is equally effective in reducing body weight in both men and women.“ The benefits go beyond weight loss, as clinical studies have shown benefits of IF for epilepsy, Alzheimer’ s disease and multiple sclerosis,” she adds.
YOUR GUIDE TO STARTING
If you are intrigued, Dr Wolberg offers these guiding principles:
• Start slowly when beginning any IF diet.
• Expect an adjustment period of 1-3 weeks.
• Headaches may occur initially but usually subside with increased water intake.
• After the adjustment period, normal exercise routines can be resumed.
• During eating windows, ensure all macro and micronutrient needs are met.
• Include fruits, vegetables, and whole grains to boost fibre and micronutrient intake.
• On fast days( ADF and 5:2 diet), consume at least 50g of lean protein to reduce hunger and prevent muscle loss.
• Moderate alcohol intake is allowed on feast days and during eating windows of time-restricted diets.
• Caffeinated beverages and diet sodas are permitted during fasting windows.
• Limit diet sodas to two servings per day to avoid increased sugar cravings.
• Maintain consistent water intake to stay hydrated.
• Required water intake depends on body weight.
TREND OR LIFESTYLE CHANGE?
For now, Dr Wolberg warns that because research is limited about the long-term health benefits, it’ s hard to make a call.“ But, although IF is not for everyone, there could be health benefits for some individuals beyond weight loss alone.”
Whether IF proves to be a lasting lifestyle change or just another dietary trend, its potential benefits make it a tool worth exploring with caution, patience, and an eye on the evolving science. IB
APRIL 2026 / INBOUND SA 55