An introduction to fasting and its benefits
Fasting is when someone chooses to refrain from eating for a certain period of time. Eating patterns that involved periods of feasting and fasting go back to times when people were hunter-gatherers, and food wasn’t always available to put on the table.
Fasting provides significant health benefits, not just helping with weight loss and improving blood glucose levels, but also repairing damaged cells and reducing the risk of diseases such as dementia.
Types of Fasting
There are different types of fasting:
- Daytime fasts - this would include the Muslim period of Ramadan.
- Multi-day fasts - where you fast for more than one day at a time.
- Intermittent fasting - regular fasting patterns that switch between periods of eating and periods of fasting.
Intermittent fasting approaches
There are two main approaches:
1. The 16/8 cycle: This generally involves skipping breakfast and restricting eating to 8 hours e.g. 1-9pm. Then you fast for 16 hours.
2. The 5:2 diet: With this approach, you only eat 500-800 calories (the equivalent of one healthy meal) on two days of the week.
Healthy Eating while Fasting
Try to avoid feasting on high carbohydrate foods.
The ideal balance is shown in the healthy eating plate to the right, which gives the recommended proportions of different food groups.
Foods to eat:
- Eat balanced meals using the healthy eating plate above. Ideal proportions are half a plate of vegetables growing above the ground, quarter a plate of protein (e.g. meat, fish, nuts, seeds, full-fat dairy), and less than a quarter plate of whole-grain carbohydrate.
- Eat more vegetables that grow above the ground (such as green beans, spinach, broccoli, aubergine, mushrooms), as well as protein and healthy fats (such as olive oil, nuts, seeds and oily fish). This will help keep you feeling full and avoid big spikes and dips in your blood glucose levels.
- Increase quantities of lentils, pulses and beans in your meals. Start meals with salads, soups, fruits, and lentils.
- Eat plenty of full-fat yoghurt or milk-based foods. This will help you feel full for longer as well as ensuring adequate calcium intake. Try plain or Greek yoghurts with vegetables or low sugar fruits (e.g. berries, apples), seeds and nuts.
- Drink plenty of water before starting the fast and during the day if the fast allows. It is advisable to consume at least 8 cups of water per day (at least 2.5 litres) so that your body may adjust fluid levels in time for the next day.
Foods to avoid:
- Limit amounts of high sugar fruits, particularly dates, grapes and tropical fruit (e.g. mangoes and pineapples) and avoid drinking fruit juice. Fruit juice contains very high levels of sugar.
- Limit starchy processed foods such as white bread, rice, couscous, noodles, chips and pizza. These will cause your blood sugar to rise and will tend to cause increased hunger and weight gain.
- Avoid sugary foods such as chocolate, cakes, biscuits and pastries. A much healthier option (which will keep you feeling fuller for longer) is plain yoghurt with some low sugar fruit (e.g. berries).
- Avoid deep-fried foods such as samosas and chips. Measure oil you use in cooking and ideally use plenty of unprocessed oils including butter or olive oil.
- Avoid caffeinated drinks such as tea and coffee as these can act as diuretics.
- Avoid sugary drinks such as orange, apple and tropical fruit juices, and fizzy drinks as well as diet cola.
