The Big Fast

Fasting isn’t new to me. Every few weeks, I usually take a day to fast—not for any specific reason, just because I’ve heard it’s good for you. It’s said to cleanse the body and refresh the mind. But this time, it’s different. I’m committing to a full week of fasting—no solid food—and this time, I have a clear reason.

My weight has crept up to 16st 7lb. My BMI is 30.6, and more concerning is my body fat percentage, now at 18.6%, with a visceral fat score of 12. To some, that might not sound alarming, but for me, it’s a wake-up call. Time to act before things get worse.

For context, here’s a bit about me:
I’m a 56-year-old man working in an office. I used to be a heavy drinker—almost an alcoholic, if I’m honest—but now I drink only occasionally, and rarely more than a pint. I don’t smoke. I’m fairly fit and run over 25 miles a week. However, over the past year, I’ve focused so much on running that I’ve lost some of the upper body strength I once had.

Day 1 – Sunday
Starting stats: 16st 7lb | 18.6% body fat | 30.6 BMI

I kicked things off Saturday night with a light dinner: pan-fried haddock and a green leaf salad—my last solid meal for six days.

Sunday morning began with a 3-mile walk with Betty, our Shar Pei, followed by an espresso and a 10-mile run. After a shower, Paula (my fiancée, who’s doing this fast with me) and I headed to IKEA for some hooks for our new glass wasp traps. Two hours later, we came back with the hooks—and a new garden gazebo. Classic IKEA trip.

The afternoon flew by as I set up the gazebo in the blazing sun, sipping on a pint of zero-sugar lemonade. In the evening, we took Betty for another walk, watched a bit of TV, and wound down with a cup of Earl Grey before bed.

Day 2 – Monday
Morning Weigh-In: 16st 4.8lb | 18.4% Body Fat | 30.3 BMI

A great start! Encouraging to see the numbers moving in the right direction, but I know consistency is key. I kicked off the day with a strong espresso before heading into work.

Fasting at the office is no easy feat. My colleagues seem to be constantly eating or sipping on something, and lunchtime is a parade of temptations—pizza, jacket potatoes, McDonald’s, KFC, and those massive cream cakes. To avoid the struggle, I steered clear of the canteen altogether and stuck to just two small glasses of water throughout the day.

When I got home, Paula was feeling a bit peckish, but we stayed strong. We laced up our shoes, grabbed Betty, and headed out for a long walk—an hour and a half of fresh air and distraction. We wrapped up the evening with a comforting cup of Earl Grey and a quiet night in

Day 3 – Tuesday
Morning Weigh-In: 16st 2.6lb | 18.1% Body Fat | 30.0 BMI

Seeing the numbers drop again this morning gave me a real boost. Despite feeling a bit hungry, I felt more determined than ever to stay on track and hit my goal.

I hadn’t slept well the night before—kept waking up—but I was up at 4:45am to take Betty on her usual 3-mile walk. After that and seeing the scale, I felt re-energized and ready to face the day.

With a protein shake in me, I headed off to work. Since I had a run planned for the evening, I decided to allow myself a little something at lunch: a coffee and a small pot of fat-free yogurt. It really helped. I noticed a clear improvement in my focus and productivity during the afternoon—something to keep in mind for the rest of the week.

I got home around 5pm, had another small protein shake, and changed into my running gear, including a sweat vest. I ran 3 miles to meet up with the lads, then we did another 7 miles together. I was feeling great—running at a 9-minute mile pace, sweating in the heat but full of energy.

Then, everything changed.

About 2 miles into my solo run home, a wave of nausea hit me mid-stride. My legs suddenly felt weak, and my vision filled with psychedelic colours. I stopped running and tried to keep walking, but the dizziness wouldn’t go away. My legs barely wanted to hold me up, and I felt like I might throw up. My head was spinning with thoughts—had I pushed too far? What if I collapsed out here, alone on a quiet path?

Thankfully, I didn’t collapse, but I was in a bad way. I managed to get home, took a cool shower, and downed a pint and a half of water. It was a sobering reminder that even with determination, the body has limits—and I need to listen to mine.

Day 4 – Wednesday
Morning Weigh-In: 15st 8.4lb | 17.4% Body Fat | 30.0 BMI

Another rough night—broken sleep, a thousand dreams I couldn’t remember, and a pounding head when I finally gave up and got out of bed at 4:30am. Betty and I headed out for our usual 3-mile walk, but it was a slow one. I felt drained, irritable, and on edge. When Betty lingered a little too long sniffing some rabbit droppings, it took everything in me not to snap at her. And those chirping birds? Not helping.

Back home, I stepped on the scales and was genuinely surprised by the numbers. I’d hoped to see this kind of progress by Day 6, so hitting it now gave me a much-needed lift.

I grabbed a protein shake and an espresso, then set off for work feeling a bit more upbeat—until a car “pulled out on me.” In hindsight, he had a good 100 metres of space and I wasn’t really that close, but in the moment, my blood boiled. That irritable mood stuck with me all day.

At 4pm, I jumped on a podcast recording with Wil Chung and TMHQ, but I found my mind wandering. I had another podcast scheduled for 6pm, but thankfully my friend Ian agreed to push it back to 8pm so I could try to reset. It didn’t really work—but hopefully no one noticed. Or maybe you did.

I ended the day with a calming cup of Earl Grey and headed to bed, hoping for a better night’s sleep. No such luck—another restless one.

Day 5 – Thursday
Morning Weigh-In: 15st 10.4lb | 17.5% Body Fat | 29.2 BMI

I’d put a little weight back on, which I expected since I hadn’t done any exercise the day before—but it still annoyed me. I couldn’t see the silver lining. Even though I’d lost nearly a stone in just five days, I couldn’t appreciate it. Frustration was creeping in.

After walking Betty and grabbing a shower, I had over an hour to kill before work. I had a few things I could’ve done—like editing four podcasts—but my brain just said, “Forget it,” and I listened.

With a protein shake and an espresso in me, I drove to work on autopilot. In a morning meeting, I struggled to keep my eyes open. Everything people said irritated me. I could feel myself spiralling—mentally and physically.

Paula wasn’t doing great either. She looked tired, and I could tell she wasn’t herself.

By lunchtime, after nearly an hour of reflection, I made the call: the fast ends here.

My body was clearly starting to shut down. I was overwhelmed with anger and irritation, my brain was foggy, and my muscles felt like soggy oysters. I was on the verge of snapping, and I didn’t want to go there.

So, I grabbed a protein mousse and some fruit. And almost immediately, I felt better. The fog began to lift, I cracked a smile at a joke, and I felt more like myself—more sociable, more human. That evening, Paula and I treated ourselves to a well-deserved homemade chicken fillet burger, topped with a generous spoonful of garlic jam. On the side, we had a refreshing green leaf salad, brightened up with fresh strawberries and a hint of mint. After five intense days, it felt like a small celebration—flavourful, nourishing, and grounding.

Lessons Learned

This experience taught me that the body can be pushed to new limits—but it’s crucial to stay mindful of the consequences.

Yes, I lost weight. But was it worth the toll on my mental stability? I’m grateful I recognised the warning signs before things went too far—before I said or did something that could have had a lasting impact on others, or on myself.

I’ll definitely fast again, but with more structure. Going forward, I plan to commit to a few fasting days each week. After the first two days, I felt fantastic—energised, mentally sharp, and emotionally positive.

I’m also making a conscious shift toward cleaner eating. Having gone nearly five days without any refined sugar, I now feel confident I can stick to natural sugars like those found in fruit. So, it’s goodbye chocolate digestives, and hello strawberries!

If you’re considering something like this, my advice is simple: don’t wing it. Seek proper nutritional guidance from a qualified professional. And make sure you have someone in your corner—someone you trust—who can give you honest feedback about how you’re doing. You’ll need it more than you think.

Alan "Muddy Duck" Moore