In 2019 I adopted LCHF/keto (eternal thanks to @garytaubes).

I had to defy medical recommendations and give up foods I loved. But it worked. I lost fat and put my incurable disease into remission, to the surprise of my doctor.

But keeping it up for years had its challenges.

Even when you essentially stop eating carbs, it's still hard to get into deep ketosis (the metabolic state where you release and burn your stored fat). It's even harder to stay there for more than a day or two.

I did plenty of experiments to understand what would work for me.

Besides adding and removing various foods, I experimented with 5:2 intermittent fasting and with time-restricted eating (no food outside a 6-hour window within the 24 hours).

I had tried 5:2 before discovering LCHF/keto and it hadn't worked. The next day I'd eat twice as much.

Time-restricted eating worked better for me. Skipping breakfast was easy now, since keto greatly reduced cravings. For a while I even condensed that to just one meal per day.

Not as hungry as I feared I'd be. And, my logs say, in 2 months I dropped the 5 kg I had put back on.

I then also tried 5:2 again. Being on keto (hence reduced cravings) made it a lot easier than when I had tried it years before, and I was no longer eating ravenously the following day.

But the ketosis I reached that way was still only mild.

I kept experimenting, with daily measurements (including finger pricking for ketone measurement), seeking to understand how my own metabolism worked.

Did it matter if I fasted the same day that I had an intense kendo practice in the dojo? (Oh yes. The benefits compounded.)

One day, a Trinity colleague wanted to have lunch with me but I told him "Sorry, not today, I'm fasting". He was intrigued that I'd do that twice a week. 

We ended up discussing fasting. He told me he fasted for a week once a year. A WEEK? I had never ever met anyone who did.

Long story short, I started researching multi-day fasting. One surprising secret I learnt was that ghrelin, the hormone that makes us feel hungry, goes down dramatically after the first couple of days without food.

This all makes sense, from the perspective of our hunter-gatherer ancestors. You hunt the big game, you feast on it, but then no more food until the next kill. In the meantime, you live off your fat reserves.

And you stop secreting ghrelin, because why would you need to?

One day I took the plunge and tried it myself.

I set myself a target of one week, but with the safety-net freedom that I could stop anytime if I found it unsustainable. To my surprise, it was all much easier than I thought.

The first day I was a bit hungry, but not much, and I was used to that from 5:2 anyway. No big deal.

Beyond the second day, though, I basically stopped feeling hungry at all. I might "like the idea" of eating something, but it was in no way a physiological need. Just psychological. My body didn't require it. I could clearly feel the difference.

Ghrelin had actually gone down.

Another unexpected outcome was that I could still engage in hard physical activity without feeling weak for lack of food. I could have my usual intense 2-hour kendo session in the dojo, sweating hard, and give it my all.

My body got all the energy it needed from fat reserves.

I did eventually get into relatively deep ketosis (above 2 mmol/l), but only after 4-5 days of fasting. At my age, I had never got to those levels by LCHF/keto alone.

But the main thing is: I felt great!

I had high energy, high awareness, I naturally woke up earlier. I could concentrate more. I felt great (as well as proud).

It felt like a deep cleanse.

The added bonus was that I saved many hours per day: not just eating but also cooking, washing dishes, shopping etc.

Clearly this could not go on indefinitely, though, or I'd become emaciated. I stopped after a week not because I was hungry (I wasn't) but because I did not want to start losing muscle mass instead of just stored fat.

But it was an eye-opening experiment.

Personally, I would not recommend multi-day fasting other than to a committed LCHF'er. Before I stopped carbs, my cravings would have been too strong.

Plus, the idea is too radical. Years ago, I would have just said no.

Much easier results will come simply from basic LCHF/keto.

However, as someone committed to LCHF for life, I found a week-long fast to be an advanced tool to reset my metabolism into deep ketosis when my daily measurements tell me it drifted away too much.

A powerful weapon well worth having in my arsenal.

It was that serendipitous chat that made me realise that a multi-day fast was even possible for a regular guy like me (I mean, I'm not one who sleeps on a bed of nails).

And the health benefits were evident, and measurable.

YMMV, but perhaps this will open your mind too.

My big discoveries from this experiment on myself:

• Being already on LCHF/keto made it easy to start a long fast

• Hunger did really disappear after a couple of days

• The true reason for eating every day is social, not physiological

If you enjoyed this, and it opened your mind to new possibilities like that conversation with my colleague did for me, then jump back to the top, like & retweet:

If you are interested in ways to regain health & vitality, follow me @FrankStajano as I share how I challenged medical dogma, adopted this frowned-upon LCHF/keto "fad diet", eliminated my dangerous visceral fat and put an incurable disease into remission.