Intermittent fasting. Time restricted eating. The 5:2 diet. They’re the latest thing in health but what do these buzz words really mean, how do they differ, and are they good for you? This article takes a deep dive into the research and benefits of these new health trends, and why we should care.


Popularised by Michael Mosley in his 2012 documentary Eat Fast, Live Longer and his book The Fast Diet, intermittent fasting (IF) is a broad term that encompasses a range of eating patterns where you cycle between periods of eating and fasting. In essence, IF is about when, not what you eat. There are many forms of IF regimes that have proliferated in health pop-culture. They are:

  • Time-restricted eating – Fasting for 12-hours (or longer) every day with a 12-hour eating window. Other popular models include the 16/8 method which sees a 16-hour fast with an 8-hour eating window.
  • Eat stop eat – Fasting for 24-hours once or twice per week.
  • The 5:2 diet – Restricting your calorie intake to 500-600 calories two days a week, and then eating as you normally do for the other 5 days.
  • Alternate day fasting – Fasting every other day (one day on, one day off). On fasting days, approximately 500 calories are recommended.


There is a significant body of research on IF, including hundreds of animal studies and dozens of human clinical trials. The results have shown IF to be effective in improving a range of health conditions including obesity, diabetes and cardiovascular disease.

So, why does IF seem to work? In essence, its positive effects can be attributed to a term called ‘metabolic switching.’ Scientists have found that after fasting, the body starts to burn ketones instead of glycogen (a form of glucose) which burns fat. Fasting also activates functions that help to clear out toxins and damaged cells, enhancing brain function, reducing the risk of cancer and improving inflammation.

However, it’s important to note that everyone is different, and IF may not be the best eating plan for you, especially if you suffer from diabetes, low BMI or other health concerns. If you’re looking at giving it go, consider chatting with your GP, especially if you’re on medication. Fasting for kids is also not recommended


If you’re curious about IF, but you’re not sure where to start, here are some quick and easy suggestions to try.

  • Start by skipping breakfast. It may sound counter-intuitive, especially as we’ve grown up with the belief that ‘breakfast is the most important meal of the day.’ But skipping your first meal automatically extends your fasting window – easy.
  • Try to limit your snacks between meals and stick to main mealtimes e.g. lunch and dinner. Alternatively, if you avoid snacking after dinner, you can begin your fast straight after teatime.
  • Drink a variety of fluids during your fast. Keeping well hydrated is key when fasting. So, whether it’s water, tea, calorie-free soft drinks or black coffee, a range of different drinks can make fast times more enjoyable.
  • Checkout Michael Mosley’s cookbooks for low calorie meal inspiration. We suggest selecting foods with high water content such as grapes, or low calories (but filling) such as popcorn or raw veggies.
  • Write down why you want to try IF. Look at this when you have hunger pangs and remind yourself of the outcomes you seek. Being clear on your motivation is incredibly important to strengthen your self-discipline and control. It’s all in the mind!
Let Them Eat prides itself on low-calorie, wholesome food perfect for IF.  Simply head down to a Let Them Eat location near you.