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Participant blog for Ian Lake during Zero Five 100 Study


Route Henley on Thames to Midgham. 24 miles. The route we had chosen was along the entire length of the Kennet and Avon Canal with an eastward extension to enable us to complete the distance of 100 miles. We had planned to finish on the eve of the Public Health Collaboration Conference in May, but COVID meant that we had to delay the project.  Henley was a great backdrop for the start of the event. Our HQ for the start was a room in a pub! We had decided to meet up ‘on the day’ which made for an interesting and frantic morning. 

Some people had been having trouble with the CGM ( continuous glucose monitor)sensors or had not had time to fit them. We had no meeting room as such, so had to adapt a room which had dodgy Wi-Fi. Pete, our metabolic breath tester did his best to get his connection and it took longer than expected for everyone to get tested. We could not get our minibus close to the hotel, so everyone had to shuttle on foot between the start venue and the hotel. 

Thankfully, everyone gradually made it to the start line, making their introductions as they went. 

We had all stopped eating at 3pm the previous day but you would never have known. No one claimed to be hungry and were excited and fully focused on getting underway. We finally did get going rather late at 11:30. With a longer distance to cover than any other stage of the route, it was going to be a challenge to get to our next stopover before dark. We had the most perfect weather with a gloriously sunny late summer, which was to last for nearly the whole trip. Not too hot, not cold. 

We clocked up 25 miles in the end with a couple of people arriving after dark. Still, we managed to get a short meeting in our hotel and share our experiences. Most of us had taken a detour at some point. But psychologically it was good to get a quarter of the distance completed on the first day.

Diabetes management. 6u Tresiba 1u Novorapid

Daily Sensor Report for 19th September 2022

My usual daily diet regimen is to fast for 18 hours and aim for around 30g of carbs a day to be eaten in a six-hour window. I typically take  8 units of long-acting Tresiba twice a day (I could possibly do a single 16 u dose but got into a habit with Lantus and never saw the need to change). I  usually  find that I need 2 units of Novorapid on waking to cover the stress hormones and likely also the coffee. I usually take 4 units of Novorapid with the main meal. I eat twice a day usually, but the first meal is usually a snack at around 2pm.

 Dialing Down The Insulin Dose.

I had done three fasts for training in the three months before the start of the event. Three days, and six miles a day, four days and twelve miles a day, and three days and eighteen miles a day. I knew therefore that I had to dial down the insulin to around six units a day over two days. 

 I was also trying to avoid the need to rescue hypos with glucose tablets. So, from experience, it was to be 6u Tresiba in the morning. With lowish glucose this morning, I used no rapid. It turned out to be slightly too high a dose, but only just. Glucose was slowly rising throughout the morning. Could this be too little Tresiba or just stress hormones caused by the excitement? With an upward trend on the CGM, I shot up a single unit of Novorapid. This had the effect of causing overcompensation and the CGM alarm was squawking for most of the afternoon, indicating glucose of 3.1mmol/mol. 

The strange thing was that I felt good, I had no hypo symptoms, so I held out until the evening. Low glucose was to be a common finding with non-diabetics. They also felt well. We think that 4mmol/l in a keto state might not apply in a keto state. Se all felt well at 3mmol/l. 

I had decided on a strategy of using glucagon instead of glucose to rescue hypos. Glucagon is a counter hormone to insulin and raises blood sugar. Just before bed, I decided on half a vial of 0.5mg. I had used it before to test out if it would work in a fasted state, as some diabetologists think it might not be effective on a keto diet and cite this as a reason not to go keto. That is my reason to use glucagon, explore the concern, and see if it has credence. 

Glucagon did work for me but caused some indigestion before I went to sleep which was gone by the morning. 

Lab Rat Data. 

Starting Weight 73.4kg

Metabolic breath testing 100% fat burner

Ketones 2.0mmol/l which is in the ketosis range.

Lactic Acid 3.2 mmol/l


We woke up to another perfect day in an ideal setting. Our HQ had a large room where we could all meet and socially distance at the same time. So, we took over space and got our testing and stretching done. 

The daily routine was: cortisol saliva test, Ecal breath testing, ketone testing, coffee, stretching, briefing about the day ahead, bags in the van and off. 

Today’s route had few options to get lost and was mostly rural with a couple of urban sections in Newbury and Hungerford. 

I managed a good run to Newbury and beyond but had to walk for the last stretch. I had woken early with the CGM squawking. I felt okay but had some ever so slight visual symptoms that I recognised as hypo. It was time to take action. After the nausea of the previous glucagon dose (I was not 100% sure but very suspicious it was glucagon), I went for 6g of glucose tablets. This experiment is exploring keto metabolism at the extreme end. We have a good idea of what to expect and have carefully talked it through with experts who understand metabolism. But in managing T1 diabetes, we must stay safe and take appropriate action. It was never a case of zero calories for T1, and certainly not the case to hide our findings. We are measuring and reporting in good faith. It is never acceptable to try to make the data fit the theory. It should be the other way round. 

The so-called Seven Countries Study over half a century ago was highly influential in setting the current guidelines on fat intake in the diet. It was a study of 22 countries, but the countries that fit the theory were only seven. The actual scatter graph of all 22 was random. But seven joined up the dots as required. If you want the full horror and implications of this read Nina Teicholz book The Big Fat Lie. 

It was a busy path with a lot of cyclists to share it with. You knew when a town was about a mile away by the traffic. 

I have not felt hungry so far. I usually do on day two from past experience. Perhaps it is the excitement of working with a group of wonderful people. Everyone gets the reasons for doing this and are all pulling in the same direction. But when a family on a narrowboat was barbecuing some chicken, it did look and smell fantastic and tempting. We resisted!

Diabetes Management; 4U Tresiba 1U Novorapid

Daily Sensor Report for 20th September 2022

After taking 6g of glucose tablets, the blood glucose rose to 7mmol/mol. What to do? The trend was up, and we were about to set off. Coffee, in my experience, tends to kick up glucose and takes a while to wear off. From experience, I can reduce insulin the insulin volume on day 2. I opted for 4u of Tresiba and a single unit of Novoapid. That was nearly right. But as all T1 know there is more intuition than science. Carbs are only one of the things that affect diabetes control. There is a long list including sleep, physical activity, stress, other hormones (ask any woman with type 1 diabetes about the effect of periods on glucose control), etc. 

I needed a hypo rescue as my run had become a run then walk with increasingly longer walks. This is a classic sign for me of hypo. My mental function and vision were entirely normal. I decided to use just 0.3 mg of glucagon at 26 hours of fasting. It did the job well but at the cost of constant nausea and some abdominal pain until I went to bed. I am not going to use anymore! But I had shown that glucagon could work in ketosis and I found that it can work at three days when I was doing my training. 

Lab Rat Data

Ecal fat burning 94% (was this glucose the tablets I had taken on waking? Or the stress hormones? We will have to wait for the cortisol results)

Weight 73.2kg

Ketones 2.0mmol/l in the morning, 3.4mmol/l in the evening. 

Lactic acid 4.1mmol/l

CGM trace. So, on day two and over 50 hours into the fast, I remain in nutritional ketosis, my blood glucose and ketones are showing no signs of diabetic ketoacidosis. I have known this for so long that I am surprised that it is a concern in nutritional ketosis. But part of the point of this project was to monitor ketones. Anyway, after two days of nutritional ketosis, all is well. 


We were up and about for an early start. We had to get from our HQ in a Marlborough hotel and travel the six miles to our previous days finishing point.

Everyone was still feeling good both physically and mentally. A few muscle niggles here and there, and some more hungry than others, but no one came with a teacher’s note asking to be let off games. 

We are over halfway through our fast and nearly halfway through the distance. It’s a milestone, but we need to get the job done. Mileage is now the driving force. If we can keep up the pace, then we will only have 13 miles to go on the last day. The excitement will get us there. The weather is another fabulous day, but there is a prediction that it will change on the final day. Plus, with there being a COVID second wave concern, we need to get as much done as possible. We don’t know if there will be a full lockdown.

Today I felt tired. I am always up early getting the testing set up, and this might be taking its toll. 

But no aches and pains, good glucose and everyone was optimistic and rearing to go. Some set off from Marlborough; others were dropped off at various places, to restart their trip from where they finished the night before. 

It was to be the most rural stretch so far. There was a mix of narrow wooded paths and wide-open countryside with some of the hills displaying the chalk horses that are typical in this area. 

Today was mostly a walk. But it was all right. Lots of time to chat with people, generally have a good time. So difficult to get a good chat with COVID. You have to shout! We had water stops arranged, and there was nothing but pleasantness—a top day. I stopped to let a couple of cyclists pass. They were aware that we were on a challenge. Someone further ahead had said something. One of them, a woman in what looked like her middle age, took a particular interest and got it straight away. ‘So, you are just switching from one fuel to another, one that is more appropriate?’ Exactly! I remember thinking how some people get this stuff, and others just can’t see it. It must be how we are taught to think. Her friends’ daughter has Type 1. Perhaps that was it, a personal investment in the subject. It happened to me. 

We managed the full 20 miles but had to go round an industrial estate to get that distance in. The hotel was again on the route, as were but one. So it was a walk-in walk-out hotel—an excellent opportunity to get in an early start. 

We set out to explore the potential of our fat stores to provide energy safely. That is surely what the fat is there for? Anyone in the normal weight range has a minimum of 20000 calories of fat—often way more than that. A 60kg woman with a typical 25% of body fat has a whopping 130000 calories of fat stored. If you are obese, then you have far more. Those calories are there to provide energy. Fat provides twice as much energy per gram than glucose, and there is at least ten times more fat available for energy than there is sugar. The body makes sugar in the quantities needed; you do not need to eat sugar for energy. Fat will provide your energy needs for days. At some point, of course, you are going to need protein. When the sugar stores run out, the body needs to make the glucose it needs from protein. But even that will not come from muscle. We have enough protein secreted away as amino acids, called visceral protein, to use for that. We also have part of the fat molecule called glycerol which is available for energy as glucose. Our body is an incredibly complex adaptive system. How long before we start breaking down muscle? Anecdotally five-day fasts do not cause muscle breakdown.

To some extent, metabolic breath testing will give us a small clue but not a definitive answer. It turned out that almost all were burning fat on the last day. But of course, at some point not eating is unsustainable and injurious to health. We chose five days because we wanted to partly out of curiosity to see what happened. That’s the scientist in me. And also because five days would ensure that the physical activity would be manageable. Twenty miles a day is achievable by most. It was never an endurance challenge in that way. We needed to burn 20000 calories, and walking or running seemed a pleasant way to do it. 

Diabetes Management 4U Tresiba 1U Novorapid

Daily Sensor Report for 21st September 2022

This was an interesting one today. I had lowish but manageable glucose for the past two days. The question was whether to use any long-acting at all. I could use short-acting whenever. I elected to omit the long-acting. I used no short-acting either. There was a steady upward trend, but I never needed insulin until the evening when I decided that four units of Tresiba and one unit of rapid were okay. And this was the right formula. I had taken no insulin for 24 hours

Lab Rat Data. 

Cortisol 16.1nmol/l 

Ecal showed 100% fat burning. 

Morning ketones 4.0 lactate 3.4

Ketones 5.7 the highest so far

Lactate 15.7, not sure where that came from. I cannot yet understand the mechanism. Lactic acid usually comes from anaerobic glucose metabolism. But there is some evidence that when fat burning, there is glucose produced from a part of that fat structure. Stored fats are called triglycerides because three fat molecules are attached to practically half of a glucose molecule. It’s called glycerol. There are studies to show that glycerol directly affects lactic acid levels. So that might explain it. I think it is mainly sugars that make lactate, and these can be made by protein other than muscle. Some intelligent doctors are working on it. I will post here if I get an answer. 

The lactate was back to normal keto levels the next morning. 


The team were now visibly excited to be on the home straight. And with another perfect late summers day, likely to be the last of the summer, there was a chance of another strong performance by the look of everyone waiting to get going. It has become a challenge now to get in the miles and keep ahead of the target. Those two early days have set us up for a comfortable ten-mile stretch on the last day. But today we must stay focussed on getting to Bath. Everyone set off at different times. It was to be the pattern until the end. 

I was last to check out, see Pete, the Ecal breath-test man off, and say goodbye to the hotel staff. The manager shared her story having found out what we were doing. She too had started the keto diet and was pleased to see some more medics making this trip. She had asthma and was taking an immune suppressant drug for it so she must have had some underlying inflammation. She had the look of someone who had taken a lot of steroids in the past. Anyway, it turns out that her respiratory consultant gave her the name of a book on ketogenic diets. He had recommended it as a complementary treatment for her condition. She was only three weeks in but was feeling the benefits already. Seeing us, gave her a boost. 

Daily Sensor Report for 22nd September 2022

I thought what a great way to do medicine, treat the patient by restoring her metabolism to optimum,  then manage the rest as needed. Top Doc! I thought. Hopefully someday soon all of medicine will be done like that. I know the desire is there amongst a lot of doctors. They need the confidence to know that it is safe. That’s why we find ourselves in Devizes. 

After walking a few miles, I found some new energy and pretty well ran the whole distance. It was my first perfect day, and I was pleased that I was performing well, especially after yesterday’s slog. 

Today I felt that I could go the whole way to Bristol without stopping. I’ve no real clue as to why. The body presents us with a lot of opportunities to learn that’s for sure. But I did stop in Bath, got lost in a seemingly endless loop courtesy of Google Maps, and arrived a full hour late because of that. To be honest, after five years of keto, I have never felt as energised as this. It sounds a bit silly, but I felt ‘connected’. My body felt good ( done that). My mind felt good( done that). But I’ve never recognised the two joining up.

Everyone participating was pretty stoked by this stage. Some say it is the euphoric effect of ketones. I know Steve mentioned this in one of his Tweets back on day two. It felt to me like being what a human should be. Some of those great nature photographs where you see a horse running wild, or an eagle enjoying the thermals. Or even a dog that is rolling in the grass, just being natural. Well, that’s what it was like, and right through the next day. It was probably all that lovely countryside adding to the effect. I got a small glimpse of it when doing another long-distance run on a keto diet. But the outcome wasn’t sustained for long enough, just enough to hint at something more. Now I know. The whole group are recording their mood, sleep, and hunger state, so the data we get will be fascinating. 

Diabetes Management. 0U Tresiba 1U Novorapid

Daily Sensor Report for 23rd September 2022

I had an excellent trace with a tendency to go low. The glucose meter was squawking to the early hours, and I opted to take 6g of glucose tablets at 0230. My left leg felt slightly numb. It wasn’t weak, but of course, I wondered if it might have something to do with the low sugar levels. It was more likely to be the back or the way I was sleeping, but I decided to ‘play safe’. 

It was gone in the morning. I took just a single unit of rapid-acting insulin with a blood glucose of 5.8. As it turned out, it was the right decision. By the end of the day, I had got a nice flat trace. It was becoming the norm. 

Lab Rat Data.

Weight 71.6kg

Ecal 100% fat burner. 


Ketones 4.2mmol/l

Lactate 3.4 mmol/l


It was almost a formality to get to Bristol today.  For various reasons, everyone had a different mileages to complete today to reach the target of 100miles. Steve and Jake set off at a pace to get to a four marathon distance. I  only had a ten and a half-mile run into Bristol and two hours later would be able to break the fast. To be honest, hunger was not an issue. I wasn’t hungry. I was alert and in a good place. I can’t remember being hungry since day two. In fact, if pushed it, I would be happy to forgo food until breakfast. But this never was a run until you drop sort of activity—just an experiment to explore the science of keto. 

We dropped out of Bath and intended to follow the canal but for some reason ended up on the wrong side of the River. Barry, the minibus driver and all-round fixer, plus the camera team rang us to say that the tracking app had found us to be way off course. We were on the A431! Yep, we had followed the path and got lost. I was running with Ali, so we opted to cut our losses and take the high road. And high, it turned out to be. The A431 is an undulating road to Bristol. We put in an extra mile whilst waiting for the transport to pick us up. We had done it! 100miles on zero calories over five days. Everyone had made it safely and pretty well without any fuss. We were pleased to have finished so strongly, and yes, it was a challenge. But to be honest, it was all over by day two. At that point and almost half distance we were, all of us, well, upbeat and injury-free. And so it turned out to be for the whole trip.

I never stretch but probably should. I never warm up. My pace is only ten-minute miles. If I warmed up, I would be walking! But I never seem to get injured. My worst day was day three when I was aching. But that was because I had walked a lot. I used muscles I had not trained. By day four and when the running finally cut in, everything was okay. I had slightly stiff muscles at night but nothing to worry me. I remember in the pre-keto days that finishing a half marathon was a painful experience with the effect lasting a couple of days

.This week I have woken up fresh as a daisy. How life has changed, and how wonderful it would be if we could get that message to others. I accept that one day I will fall ill, but I cannot comprehend what it must be like to succumb to an illness and then find out that I might have prevented it. We had a meal to break the fast and celebrate a successful outcome. The restaurant was all you could eat meat. The staff had no clue what we had done. But we were the first customers who all asked for the fattiest cuts of meat!

This will be one of those events that live in the memory. The tenacity of the group in the face of one COVID cancellation then another severe restriction on movement made life difficult, But everyone was determined to do this. This was a great success. The next stage is to make sure that those who need it get the correct and skilled information to transform their life chances by at least having keto as an option. Onwards.

 Diabetes Management 

No insulin until the meal. 

It was back to the usual regimen when I re-fed. 

 Lab Rat Data. Lactate 1.8 mmol/l

Ketones 3.1mmol/l

ECal. Fat Burning 78% ( need to check but around there). Was this a case of some protein scavenging? Today two or three people were changing their profiles. It might be that the fasting limit for me is four days. There might be other explanations. Others are still 100% fat. But that is the beauty of this project. We learn from what we find. Every human performs differently. No one is ill. I very much doubt 100-mile runs in five days fasted will catch on. It was never the point. Neither was it a demonstration stunt—just a good old fashioned endeavour to learn. Very unfashionable, I know.

The Next Two Days:Day 1 post-event ketones 2.0 mmol/l  lactate 2.3 mmol/l

Day 2 ketones 2.1mmol/l lactate 2.3mmol/l

My glucose control wasn’t good for a couple of days. I had some insulin resistance on re-feeding that started soon after the meal and continued a couple of days with levels up to 10mmol/l. I’ll have to look into that. Some definitely was due to the stress of preparing the reports and handling some already hostile media. They had managed to get experts to comment on a few first tweets which did not give enough information on what this is about. That’s never wise for an expert in my view. Some of the insulin resistance was due to nibbling on keto when stressed. I think that just in the same way that our brains like a good nights sleep, our gut needs a good rest too. It happens to all of us. After a few days, I have finally got control. But that is what science is about. Learn from what you have, not take a narrative and manipulate data to suit. Anyway, that is what happened to me. Scientific integrity is our responsibility. 

Electrolytes. I never felt that I needed any. But I took magnesium on 3 of the five days and had a rock of Himalayan salt to lick on the route. I pinched some from others as well. But on weighing the rock on return, it seems that I only consumed 6g over five days. It seems low, but I was never ill or tired. Perhaps a rethink?