“Complete abstinence is easier than perfect moderation.”
This article is a follow up to the “How to use your glucose metre as a fuel gauge“ article, which has been quite popular, with lots of people reporting success in lowering their blood glucose and recalibrating their hunger signals by using the numbers they see on their glucose metre.
To recap, the process revolves around the idea that, perhaps even better than calorie counting or carbohydrate counting, the numbers you see on your blood glucose metre are a good indication of whether you are running low on fuel and need to eat or whether you are just eating out of habit, routine, social boredom or for entertainment.
While eating for pleasure occasionally or as part of a celebration is fine and part of enjoying life, in the long run, most of us need to find a way to obtain the nutrients we need with less energy if we want to avoid obesity, diabetes and all the associated negative consequences.
If we eat highly insulinogenic low nutrient density foods regularly our insulin levels stay high and our fat stays locked in storage and hunger drives us to eat more frequently. However, if we reverse this cycle to lower our glucose and insulin to normal levels we start to eat less frequently and we allow our stored energy to flow out of our fat cells, our appetite decrease and there is a good chance we will lose weight and gain health.
The table below shows the simple process whereby someone could decide if they really need to eat. Using this process would ensure that their blood glucose levels continue to trend down as their excess energy in their bloodstream and vital organs (pancreas, liver etc) flows out of storage.
|> 7-day average, well slept and low-stress||delay eating and/or exercise and wait for blood glucose to come down|
|< 7 day average||if hungry, enjoy nutrient dense foods that align with your insulin sensitivity|
|< 73mg/dL or 4.0 mmol/L||if hungry, eat higher insulin load foods and delay exercise|
Using numerical outputs to guide our decision making
There is no end of debate as to whether a calorie is a calorie or whether calories matter. Rather than tracking estimates of inputs like calories eaten or calories burned in exercise, there is nothing like tracking outputs such as your blood glucose levels, waist or weight to understand what your body is doing with the food you are eating and whether you are eating too much or too little.
If your glucose levels, insulin, waist or weight are increasing then chances are you’re eating too much, too often or the wrong type of food.
The plot below is a stark reminder that our chances of living longer improve if we have lower body fat levels or a waist to height ratio close to 0.5.
The problem with tracking glucose levels
The ‘problem’ with tracking blood glucose levels is that, in time, with regular fasting, our glucose levels will normalise to healthy levels but we may still be left with excess weight. So where do we turn once our blood glucose levels are optimal but our body fat levels are still above optimal?
This brings us to the star of this article, Rebecca Latham, who is a great example of how you can use your body measurements to guide your feast / fast cycle to achieve your long-term goals.
Rebecca has been following a low carb diet since the start of February 2009. She was featured in the 2010 New Atkins for a New You as well as on the Atkins site as an exemplary success story.
After a stressful time towards the end of 2015, Rebecca Latham decided she needed to make a focused effort to her lose some extra weight that had crept on. Rebecca is also particularly motivated by her family history of ALS, Parkinson’s Disease, dementia and cancer and her own ongoing battle with Type 2 Diabetes.
On 1 January 2016, Rebecca set an initial goal to lose 0.2 pounds per day over three months. Rebecca was also eager to reduce her fasting blood glucose levels from the 100 mg/dL back to the 70 mg/dL that they had been at before she regained her weight.
Part of Rebecca’s inspiration comes from her uncle, Buell Carlton Cole.
He was general surgeon to the President of the United States, who would control his weight by simply not eating until he returned to his goal weight. I initially thought this was an unhealthy approach until I read up a more about intermittent fasting.
Rather than simply not eating until she achieved her goal weight, Rebecca’s system involved not eating on days when her weight in the morning was above her target weight. Her only exception was on special occasions and celebrations.
Here are Rebecca’s weight loss results during her initial 90-day challenge. Initial weight loss can be quite quick as the insulin levels drop and the body releases water. However, it gets a bit harder to continue with straight-line weight loss as time goes on as you can see towards the end.
After the reached her initial goal, Rebecca had some issues that she needed to look after and ended up regaining some of the weight as you can see in the plot below of her weight over the past year. However, once these challenges were behind her she got back on her program.
For the final part leading up to the end of the year she has dropped her goal weight loss back to 0.06lbs per day to hit her goal on 31 December 2016. See if you can spot the few ‘blips’ around Thanksgiving and Christmas.
This chart shows that she needed to fast for about one day in three throughout the year to lose nearly a quarter of her body weight over the year!
I reached my highest lifetime weight in February 2009, when I weighed in at 158 pounds, with a body fat percentage of 43.7%. This is my scale weight chart for this past almost eight years since I started eating low carb high fat (LCHF) and nutritional ketosis.
Each time I lost weight and stopped tracking and weighing myself, I gradually put most of the weight back on again. As you can see by the chart, this happened several times, and the last few times it happened, my weight was going up a little higher each time.
On January 1, 2016, I developed and started using my Protocol. Since starting the Protocol, I took two breaks, once in May 2016 when my husband had a heart attack and I was too concerned with his health to care about my own, but I got back on the Protocol within a couple of weeks and started seeing success again.
The next time I took a break was in July 2016, when I had to eat high carb and not fast for a week in preparation for some metabolic testing. As soon as the testing was over, I was back on the Protocol and started losing again. I have been going strong ever since, with small gains here and there brought on by restaurant meals and Thanksgiving.
I have now I reached my ultimate goal for scale weight, weighing in at 122.4 pounds with a body fat percentage of 25.7%, which means that I have lost approximately 37.5 pounds of body fat. The Protocol is the only thing that has brought me sustained weight loss, and I plan to follow it for the rest of my life!
Many people have a love/hate relationship with their bathroom scale. It would be nice if a low carb or nutrient-dense diet achieved optimal health outcomes without any restriction for everyone. However, unfortunately, sustaining weight loss in the long term often takes discipline, some form of accountability and some level of restriction for most of us.
While weighing yourself every day isn’t much fun, the national weight control registry data indicate that people who have successfully lost weight and kept it off weigh themselves regularly.   Rebecca’s intended long term maintenance plan will likely be to weigh herself regularly and fast again once her weight goes outside her target range.
Better than calorie counting?
Some people who first try low carb or keto find that they initially lose a lot of weight eating to satiety as their blood glucose and insulin levels drop to healthier levels. However, in the long term, many people find that they need to be more disciplined and mindful of how much and/or how often they are eating to reach their optimal level of body composition.
The great thing about combining fasting with working to a goal like this is that it makes sure you don’t overdo the feasting days. I’ve found personally that it can be hard to know how much to eat after a fast. A quantitative system like this helps to manage and calibrate your appetite when you’re feasting.
If you eat to satiety, and not beyond, then you won’t have to fast again as soon as compared to if you binge after your fast. Eating to satiety on a regular basis means that your body’s metabolism doesn’t slow and adjust in the same way that it would if you maintained a constant caloric restriction.
Life extension benefits
There are a number of benefits to fasting:
- You can reduce your insulin levels more than if eating small but regular meals which keeps your insulin levels consistently elevated.
- Fasting gives your body a chance to repair through a process called autophagy which is where the old cells are cleaned up which allow space for the fresh new cells to grow.
- Fasting trains your body to become ‘metabolically flexible’ so you can use your body fat stores for and your food for fuel.
- There is less need to focus on the quantity of food eaten at every single meal.
- It’s not ideal to always be in growth mode with mTOR switched on. Alternating periods of growth and repair appear to be more beneficial in the long term.
- Fasting makes sense from an ancestral point of view when we wouldn’t have had constant access to plentiful food the way we do now. Periods of intentional restriction mimic what we have become adapted to and follow the seasons of the past.
Fasting also seems to have some special anti-aging effects. When food is scarce your body senses an emergency, and sends out sirtuin proteins to maximise the health of our mitochondria to increase the chance that you will survive the famine and have the best chance of living to a time when food is more plentiful and you can reproduce and pass on your genes. Unfortunately, this emergency repair function doesn’t happen when food is plentiful.
Fasting and blood glucose levels
During the first three months following her protocol, Rebecca added a blood glucose target to also bring her blood sugar down by 0.25 mg/dL per day. As you can see in the chart below her blood glucose levels have dropped pretty much in parallel with her weight loss during this time.
More recently, she tested her blood glucose levels and found that they were consistently great so she ended up discontinuing the testing because it was becoming monotonous and not helping her make useful decisions.
While it’s useful to track a few things, it can be overwhelming and time-consuming to keep track of too many things at once and lead to analysis paralysis. It’s good to find a handful of things to track that will help you make useful decisions.
Do we lose fat or muscle during fasting?
One hot topic of discussion is the amount of lean mass (i.e. or muscle) that one may lose in long term fasting.
The reality is that any weight loss is going to consist of a combination of water, fat and muscle (or lean muscle mass). The chart below from Kevin Hall’s model shows that we initially lose a lot of carbohydrates (glycogen) and with it a lot of water.
Protein/muscle loss is the smallest component of loss from the body and this decreases as we adapt more to using fat and ketones rather than relying on glucose. It takes a few days to adapt to using fat and ketones, but in the long run, they are by far the greatest proportion of energy used during fasting.
Rebecca’s experience aligns with this. She didn’t get a DEXA scan, but she does take regular body measurements which she uses to calculate her body fat percentage (see US Navy Circumference Method). Based on these measurements she lost 28.6 lbs of fat and 3.0 lbs of lean mass. So, more than 90% of her weight loss over the past year was fat.
How much to eat after your fast?
One challenge I find with fasting is that it’s easy to overdo it when you get to eat again. Telling someone not to binge at the end of a fast is like telling someone to hold their breath but then not to take too big a breath when they come up for air.
While some people can eat normally the next day after a fast, personally I find that it’s easy to reach for the energy-dense lower nutrient-dense foods or to give yourself the liberty to eat foods that you may not normally eat if you were being disciplined all the time. By doing this, I’ve found it’s still possible to maintain or gain weight when fasting more days that you eat if you’re not disciplined with what you eat on your fasting days.
If you find yourself reaching for energy-dense low nutrient density foods like processed carbs, a block of chocolate or litre of cream after your fast then you could take that as a sign that you need to revert to shorter fasting periods until you’re more fat adapted.
Another challenge with fasting is that it will deplete your system of vital nutrients in the long term meaning that you may be more inclined to binge when you do eat unless you’ve focused on maximising nutrient density in your feasting periods.
What to eat after you fast
One of the unique things about fasting is that it forces your body into the cleansing process of autophagy and primes the body to rebuild. Hence, it’s especially important to feed the parts of the body you want to grow (lean muscle mass is critical for long term health) and maximise the nutrient density during the initial refeed.
In some ways, a fast is only as good as the feast afterwards. Your body is primed to absorb all of what you give it in the refeed. If your goal is to lose fat during the fast then it’s important to build back the essential vitamins, minerals and amino acids during the feeding period.
The body will fight to get what it needs in the long run and I think you’ll have a better chance of avoiding cravings and involuntary binging if you maximise the essential nutrients of your food when you do this. And if you are using fasting to achieve long term weight loss I think it makes sense to try to get the maximum number of nutrients with the least amount of energy (a.k.a. avoiding empty calories and maximising nutrient density).
People looking to use fasting for long term weight loss may benefit from starting out with a higher fat dietary approach if they are very insulin resistant. However, as blood glucose levels progressively improve you should be able to transition to a more nutrient-dense nutritional approach which will allow you to get your required nutrients with less energy.
The table below gives some guidance as to which approach might be right for you initially based your glucose and waist to height ratio. We have developed a range of free food lists tailored to various goals that you can access here.
|average glucose||ketones (mmol/L)||waist : height|
|therapeutic ketosis||> 140||> 7.8||< 0.3|
|low arb and blood sugar||108 to 140||6.0 to 7.8||< 0.3|
|blood sugar & fat loss||97 to 108||5.4 to 6.0||< 0.3||> 0.5|
|fat loss||< 97||< 5.4||> 0.2||> 0.5|
|nutrient-dense maintenance||< 97||< 5.4||> 0.2||< 0.5|
All somewhere on the sliding scale between maximum energy density and maximum nutrient density. If we are aiming for long term weight loss, we want to maximise nutrient density as much as we can while keeping blood glucose levels and insulin levels low. Then as we improve blood glucose levels and insulin sensitivity we will be able to continue to move towards the right to more nutrient-dense approaches which will help to provide satiety and adequate nutrition with less energy.
If / when we reach our ideal weight or level of body fat, we can afford to add back in some more energy-dense foods because we are no longer trying to use the glucose in our liver (glycogen) and body fat from our belly. 
I originally started eating ketogenically a few years ago by eating very high fat, lower protein, and very low (sometimes zero) carbs. That worked for a while, and I lost weight, but as time went on, I found that I was eating so much fat and so little protein that I was getting hungry all the time.
I now get plenty of protein on my eating days. I am 5’3″ and eat 125g on the days that I feast. I find with this approach I am less hungry and my Protocol requires me to fast less often. 
Losing lean muscle mass is bad news whether you’re a bodybuilder, a diabetic or an older person battling sarcopenia. Not only will losing muscle decrease your metabolic health, glucose disposal and metabolic rate, your body will also increase appetite to regain the muscle, making it harder to keep on losing the fat.
It’s not just about looking buff and building muscles, amino acids are critical to fueling mitochondrial function and creating neurotransmitters that assist in staying happy and sleeping well. For example, the amino acid tryptophan produces serotonin which makes us happy and melatonin which helps us sleep.
The optimal food lists have been designed to help maximise nutrient density (including ensuring adequate amino acids) ideally without needing to rely on tracking calories.
I encourage you to check out Rebecca’s Facebook group where she has documented her daily progress and learnings and supports others using the Protocol. You can download a spreadsheet and start tracking and sharing your own progress. Public accountability and a supportive community are always going to be helpful in achieving such a long-term goal.
Rebecca has ‘stacked’ several different techniques from her learnings to ensure her long term success this time around to fight her genetics and tendency to regain her weight.
Before launching in, there are several considerations to tailor Rebecca’s approach to suit your situation and goals such as:
- Target rate of weight loss. Rebecca recommends that people aim for a maximum weight loss of 0.2lbs or 0.1kg per day. Anything more is typically hard to sustain in the long term. You might be feeling ambitious and this level might be easy to achieve when things are going well but it may be hard to sustain in the longer term, especially if you have a few social gatherings or parties that leave you with some catching up to do. As you approach your goal weight you may be glad you chose a less aggressive goal as the weight loss becomes a little harder to achieve.
- Social context. This type of approach can be hard to work around family or social commitments. I like to enjoy good food with my family on the weekends and save my fasting for workdays when it’s easier to skip food. When I’ve followed this protocol, it leaves me fasting Monday and Tuesday and eating dinner Tuesday night with the family or ideally a hearty breakfast Wednesday morning. Based on my scale weight I may end up fasting another day or two on Thursday and / or Friday.
- What’s your maximum fasting tolerance? Fasting gets easier with practice. You might want to start with just skipping a couple of meals, then going for 36 hours, then a couple of days. If you find your cravings are leading you to binge or sacrifice food quality, then you may want to stick with shorter fasting periods or aim for a less aggressive target rate of weight loss.
- What else do you want to measure? The good thing about measuring weight is that it’s easy. It can, however, be problematic in that there are a ton of things that influence your weight other than fat gain or loss (e.g. muscle, water, how full is your gut, when did you go to the toilet etc); it’s an easy way to measure your progress day to day. In the long term, you want to see a trend in the right direction. If you have diabetes, then you may also want to track your glucose and even your ketone levels. It will also be useful to track your waist measurement periodically to see whether you’re getting closer to your optimum waist to height ratio of 0.5, particularly if you are building muscle and hence the BMI chart categories won’t mean much for you. For reference, during 2016 Rebecca’s waist to height ratio went from 0.54 to 0.44.
How full is your stress bucket?
A word of warning, again from personal experience, is that this approach is simple, but it’s not necessarily easy. Wondering what number you will see on the scale each day can be exciting but a bit stressful. It can be frustrating when you see the number going in the wrong direction or not keeping up with your target rate of weight loss.
Chris Masterjohn has podcast How I Lost 30 Pounds in Four Months and How I Knew It Was Time which I highly recommend if you’re hoping to lose some serious weight.
A regular fasting routine is another thing that you will add to your “stress bucket” and if you don’t already have your sleep, nutrition, relationships, stress, circadian rhythm and regular activity in check then the cortisol and related insulin spikes may make achieving long term success with this approach harder than it would otherwise be.
post last updated May 2020