Intermittent Fasting: What to Eat and What to Avoid

It is often said that Intermittent Fasting is not about what you eat, it is about when you eat.

Does that mean you can eat whatever you want (and as much of it as you want) as long as you eat it during a specific time period?

Yes, it does…

And no, it doesn’t.

The majority of people who start fasting intermittently do so because they want to lose weight.

Meet my friend Ashley. Ashley weighs 110kg (240 pounds) and she has been on every single diet invented in the last forty years. She lost weight on all these diets and then put it all back on, with some to spare. She is now peri-menopausal and has discovered that this means that where in the past she could at least lose a few kilos whatever diet she started; this is no longer possible. She has severe insulin resistance and has just been diagnosed with type 2 Diabetes. Her doctor told her that her overeating caused her diabetes. The extra weight she carries on her delicate 1m66 (5.4 ft) frame causes her to suffer from near-constant back and knee pain. The pain is so bad that she cannot contemplate any form of exercise, not even swimming.

She saw on her medical file that her doctor had classified her as morbidly obese. She is so profoundly unhappy with her current weight that her doctor has had to put her on anti-depressants.

Feeling miserable, Ashley was desperately searching the internet for that one last miracle diet when she came across Intermittent Fasting, aka Time-Restricted Eating. She read story after successful weight loss story and was especially impressed by how many intermittent fasters were able to keep the weight off for months, even years after they started fasting. She watched this video:

At this point, Ashley was willing to try anything, even though she felt seriously intimidated by the idea of not eating, at all, for 16 hours every day. She went to see her doctor and discussed intermittent fasting with him. With his blessing, she decided she was going to give it a go because a 2018 review of intermittent fasting in obese people revealed that reducing calorie intake 1 to 6 days per week over at least 12 weeks enabled participants (mostly middle-aged women from the US and the UK) to reduce their weight with an average of 7 kilograms (15 lb.)

Ashley decided to start on a 16/8 (fasting for 16 hours and then eating for 8 hours — see other intermittent fasting methods.) She then had to figure out what she was going to eat during those 8 hours and what she would be allowed to eat or not eat during her fasting hours.

She researched the subject, by reading everything she could lay her hands on and came away completely confused. There seemed to be as many opinions about what to eat and what not to eat as there was hair upon her head (the hair she hasn’t pulled out yet in frustration, that is.)

Was it essential to eat a low-carbohydrate-high-fat or keto diet to lose weight while fasting intermittently, or could she really eat anything she wanted as long as she sticks to her 8 -hour eating period?

The short answer to that question, in my opinion, is yes…and no. During those 8 hours, Ashley still has to eat in such a way that she supplies her body with all the nutrients it needs. Anecdotal evidence has revealed that people who lose weight permanently while fasting intermittently look at it not as a temporary weight loss diet, but as a permanent lifestyle change. This means eating a healthy, balanced diet for the rest of their lives. So yes, she can eat whatever she wants without restriction as long as she eats healthily and no, she cannot eat whatever she wants if she wants to binge on chocolate for 8 hours every day.

Everyone is different. Some people initially lose weight while eating a carbohydrate-rich diet and later switch over to an LCHF (what is an LCHF diet?) or keto diet (what is a keto diet?) to get rid of further or the last few stubborn pounds. Other people do not lose weight unless they eat LCHF/keto right from the start.

I did not want to lose a lot of weight, en plus, the keto/LCHF set-up sounded too much like yet another doomed-to-fail diet to me, so I did not change my diet, I just cut out all sugar. I ended up with severe withdrawal symptoms for my trouble for several days. What I did want, in preparation for an operation I was due to have, was the benefits of autophagy.

Which brings us to what you can eat/drink during your fast. To benefit from autophagy, most experts agree now agree; you need to fast “clean.” Which means nothing but water (sparkling or still) and black tea or coffee — everything else has to be excluded. This was excruciatingly difficult for me, I am addicted to my first cup of coffee every morning, with a good dollop of (admittedly low-fat) milk in it. I just couldn’t get black coffee down. During the weeks I fasted “dirty,” I did continue to lose weight, but I wanted to benefit from autophagy, so I eventually made the painful switch to black coffee in the weeks before the operation. I now drink coffee-with-cream some mornings and black coffee on other mornings.

Ashley dived in at the deep end and started her 16-hour fast squeaky clean, with a normal diet during her 8 eating hours. Initially, for several weeks, she did not lose a pound, but encouraged by the support she received from others in the Facebook groups she joined she stuck with it, and eventually, the pounds started to fall off.

Making such a dramatic change in your eating habits can be difficult to maintain. I have created an Introduction to Intermittent Fasting Retreat here in the south of France as well as a Coping with Change Cheat Sheet and Checklist to help you persevere.


Disclaimer: While intermittent fasting has many potential and some evidence-based research-backed benefits, it remains a controversial way of eating. Before you make any changes in your eating habits, discuss your plans with your doctor, especially if you are on medication. People who should NOT fast include those who are underweight, have eating disorders like anorexia, are pregnant or breastfeeding, and people under the age of 18. The content of this story is for informational purposes only and are not intended to serve as a substitute for the consultation, diagnosis and medical treatment by a qualified physician or healthcare provider.