What is Glycemic Index and Load?

New article alert!

If you’ve ever wondered what on earth glycemic index or glycemic load are all about - look no further. We’ve written an article specifically looking into this - https://huel.com/pages/what-is-glycemic-index-and-load :nerd_face::nerd_face:


I have a couple questions.

  1. If GI is ranged from 1-100, then why is a baked potato rated at 111?

  2. When taking GL in account, are smaller frequent Huel meals more advantageous for weight loss, than larger infrequent Huel meals?

1 Like

I wondered the same thing about the baked potato…and also interested in the answer to your 2nd question! Wondering if I am better off doing a couple larger Huel shakes, or 3-4 smaller ones throughout the day.

Let me reach back into my brain and see if I can remember this.

It should be theoretically impossible to have a glycemic index higher than 100 if the standard for 100 is pure dextrose in water. This is supposed to be the gold standard for a test. Give 50 grams of dextrose (glucose) in water and measure blood glucose levels. Then give the same subjects 50 grams of carbs from the food you want to compare, and measure blood glucose levels. The dextrose being the absolute fastest food at raising blood glucose levels since it’s already in solution and there’s nothing to break down since it’s pure glucose. It just rapidly absorbs once the dextrose solution gets into the small intestine.

But glucose in water is nasty tasting to many people. I don’t think glucose itself is all that pleasant tasting. (It’s the fructose component of sucrose or high fructose corn syrup that gives sweetness, I think.) So researchers will often use a surrogate for dextrose in their particular study. They use white bread or something with an actual glycemic index that’s very close to dextrose, but is technically a little lower. Hence, in these tests, it may be possible to find a food that breaks down the carbs and raises the blood glucose faster than the white bread. (Maybe they should have used the baked potato as the standard. :slight_smile: )

Interestingly enough, sucrose has a glycemic index of 65 since this is one dextrose and one fructose molecule stuck together. 50 grams of it contains only about half dextrose. But it doesn’t mean that sucrose is better for us since it has a lower glycemic index.


Hey @Huel_Hefner (great handle btw!)

To answer your questions…

  1. Maybe this is a matter of wording in the article. The GI number of a food is expressed on a scale, of which pure glucose is 100. Some potatoes can have a higher GI number than pure glucose at 111.

  2. Generally speaking, smaller nutritious meals may be more beneficial to weight loss, although some studies have reported that this could be down to lower overall calorie intake versus influence of GL.


Oh Rebecca, you just triggered my intermittent fasting Spider Sense with this statement. In fact I was waiting for you to weight in (pun intended) on the second question before I added my 2 cents on this particular subject. In fact, I suspected you would actually answer his second question in this very manner.

Allow me the opportunity to debate this conventional wisdom. It’s not any kind of attack on you or assertion that you are wrong. I have no doubt that you are knowledgeable in your field of nutrition. Rather, I want to open the floor to discussion on this advise that doctors, nutritionists, etc have been giving patients to “eat multiple, small meals a day” and why in the long run this advise may be wrong and detrimental to patients. Why eating “6 small meals a day” not only is counteractive to body fat loss, based on how body fat is actually regulated. But, also, to the practical application of having to prepare and keep up a 6 meals-a-day schedule for life. (Although using Huel might make that burden easier :slight_smile:). And, ultimately, the success of lots of people who practice the exact opposite (eating large amounts of food in a narrow time restriction each day, followed by a long period of not eating) in terms of body fat loss and ease of following the regimen.

To prevent loss of work and deal with the limitations of the mobile site, I will have to continue this discussion in chunks. I will actually do the opposite of my own advice and deliver my opinion (yes, this is just my opinion) in smaller more frequent posts.

1 Like

[Extending an olive branch]

The greatest debaters understand one fundamental principal. To convince someone of your point, you must first find common ground. Let me start by saying that I see why multiple small meals a day (which I will abbreviate MSMAD) works in some people and can be good advise for certain people in the short run.

I believe the MSMAD concept came about as a “work around” or a “lesser evil” options for morbidly obese people who were consuming total daily food intake that was far beyond their energy needs. I myself was at a BMI of 38.5 about 12 years ago, so I see where this is coming from.

Let’s imagine a case study of a patient who is BMI of 40 or 45, with a large amount of belly fat. This dude has been eating very large quantities of food each meal, with a heafty amount of sugar and wheat flour and fried foods. And let’s say his total food intake each day totals about 4 to 5 thousand calories. And let’s say he does no formal exercise and has a job with little physical exertion.

Why is he obese? The first answer might be to say he overeats or that his calorie intake is greater than his calorie expenditure. And this statement is true. But is this the best answer to my question? Is saying the reason a car crashed is because of momentum the best answer? Technically, momentum is the immediate cause of a car crash, but it tells us nothing useful. The ultimate cause of the car crash is driver error, slippery road, mechanical failure, etc. So what is the ultimate / original cause of his obesity? I’m going to suggest the original insult in this pathology is too much insulin. I’m going to suggest his obesity is primarily an endocrine source. It just turns out that this particular hormone can be controlled directly by the patient by the amount, quality, and timing of his food.

1 Like

Our obese patient eats so much that his insulin levels rise very high after each robust meal and stay high for hours. During this fed state, his body is in energy storage more and carbohydrate burning mode. While insulin is high, his body stores glucose as glycogen in the liver. When this glycogen is full, his liver converts some of the excess glucose to fat (de novo lipogenesis) and ships it to adipose tissue for storage. High insulin also tells the adipose tissue to store any fat from the meal plus this converted fat. High insulin tells muscles and other cells to store and build protein structures. High insulin also tells cells to temporarily use glucose to make energy, since there is an abundance of glucose coming in from the digesting meal. High insulin tells cells not to burn fat at this time since we are storing fat for later use. This all makes sense since the patient is consuming thes macronutrients so now is the best time to store. Insulin’s primary jobs are to keep blood glucose from going too high and to tell the body cells to store and build nutrients. It’s the ultimate anabolic hormone.

Our obese patient has been overloading his body with nutrients for many years. Excessive intake of carbohydrates takes a toll on his body. Excessive glucose binds non specifically to a wide range of proteins in the body. This “glycation” of proteins is believed to be the source of diabetic complications and we measure hemoglobin A1c in diabetics because this is an easy surrogate marker for glycation of proteins all throughout the body.

But let me get back on track. This excessive glucose day after day can be harmful to cells, so cells begin to resist the call of insulin. They don’t like having to deal with the consequences of excessive glycation, so they start to partially ignore insulin since they don’t want to uptake as much glucose as what insulin is trying to command them to. As a result, the pancreas has no choice but to increase insulin release each meal, to compensate for these cell’s insulin resistance. The pancreas will release insulin in response to rising blood sugar levels while food is digesting. So it’s just doing its job. And the cells are just trying to protect themselves by partially resisting insulin’s command.

But, and this is a big but, adipose tissue does not become resistant to insulin (at least not to the extent that other cells can). Insulin tells adipose to uptake fat and store it. Adipose is not very active compared to muscle or liver, so there’s not as much uptake of glucose into adipose during the fed state, hence glycation doesn’t occur to the extent in adipose cells like it does in muscle and liver cells. This is the possible explanation to why adipose doesn’t appear to become resistant to insulin.

This battle between the pancreas and the rest of the body (particularly, the muscle and liver) is the source of continued insulin resistance in our patient who has been overeating his adult life.

To summarize: his pancreas releases a lot of insulin in response to the large meals and insulin remains high for a long time since the meals take a while to digest. He is repeatedly ingesting too much carbohydrate (and other nutrients) which are forcing the cells to deal with this. The muscle and liver cells are being forced to intake this excessive glucose to either burn it for fuel, store it as glycogen, or (the liver) convert some of it to fat. The liver and muscle cells have experienced an increase in glycation which disrupts their proper function. They don’t like it and to protect themselves they become less responsive to insulin. The pancreas tries to compensate by releasing more insulin to force the muscle and liver cells to process the glucose anyway. The fat cells remain sensitive to insulin and store more and more fat in proportion to the amount of insulin being made by the pancreas.

Now what the eff does all this have to do with the original question? I can sense some of you have already lost interest. I apologise. But I had to lay the foundation for my argument.

High insulin tells adipose to store fat. Insulin levels must fall below some threshold before the reverse can happen. there are multiple hormones affecting the storage and release of fat from adipose tissue. Insulin is only one. However insulin will override the other hormones if insulin levels are high enough. insulin tells adipose tissue to uptake fat, and it suppresses hormone-sensitive lipase inside adipose tissue which is responsible for releasing fat.

When we talk about weight loss, most of the time we are actually talking about body fat loss. I don’t think any of us want to be weaker or dehydrated. So the weight we are talking about his body fat. And, we really are targetingwhen we talked about weight loss, most of the time we are actually talking about body fat loss. I don’t think any of us want to be weaker or necessarily dehydrated. So the weight we are talking about his body fat. And, we really are targeting body fat in the mid/belly section. This “visceral” body fat. Incidentally, this visceral adipose tissue remains the most sensitive to insulin, hence this area of the body fattens more preferentially as we become insulin resistant. This is the area of the body that we are most obsessed with when we gain weight. I know I was/am.

So, to oversimplify, if we want to lose belly fat, we need hormone-sensitive lipase to become more active inside adipose tissue. This enzyme cleaves triglycerides, allowing fat to flow out of adipose and ready to uptake by body cells to make energy.

I will have to continue this discussion later as I have reached my post limit for this thread, until another response comes in. I want to show how eating MSMAD might be helpful in an obese patient in the short run, but that most people lose weight better by not using MSMAD. I want to show the logic as to how both of these situations can be true.

In essence, the obese person will lower his total daily insulin by switching from his horrible eating habits to MSMAD and will probably lose weight. However, if he were to force himself to a prolonged fasting state or force himself into a 16 hr daily fast, he would lower his insulin levels even more than MSMAD and lose even more fat. But to ask the obese patient to fast is almost assuredly doomed to fail, so MSMAD is the better option. Game theory dictates we offer him the MSMAD since he is more likely to stick to it than fasting. He will lose the weight and proclaim MSMAD is the cure. Not realizing he could have lost more fat, faster, and more conveniently by choosing an intemittent fasting regimen.

There is no contradiction. For this particular patient either method will lower his total daily insulin and cause more fat to be release and used for energy. Both situations involve him lowering his calorie intake.

I guess the point I am making is that MSMAD has come about as a workaround for obese people. This has become a red herring for the general population. If the ultimate cause of weight loss is to lower insulin, most people are better off forcing themselves to adapt to a daily fasting regimen rather than MSMAD. And particularly in people who are overweight but are not eating particularly bad, MSMAD probably won’t lower their total daily insulin that much. They will get little benefits with the big hassle of preparing and consuming MSMAD. By consolidating their total daily food into a smaller time window and by teaching their brain to be able to go longer periods of time without food, they lower their daily insulin and with much more convenience than MSMAD.

I welcome any discussion.


Hey @Deron. The predominant reason why eating more frequently (Vs more calories) is often suggested is because it is a way of reducing times of prolonged hunger - which sometimes means people over-consume at meal times. It has been suggested that by splitting daily calorie recommendations over the course of more frequent, smaller meals, people actually eat less over whole day, versus the more traditional 3 larger meals. Losing fat mass has to come from a negative calorie balance.

Thank you for all of the insight @Deron. I guess my anecdotal experience would seem to support your theory, or at least not to contradict it. I have lost weight in the past doing multiple small meals per day, but I found it difficult to stick to long term because of the additional meal prep (5-6 small meals) and I always wanted to eat more! Since starting Huel I have been loosely following a 16 hour fast/8 hour eat schedule (usually trying to eat only between 11am/12pm and 7/8pm) and I have realized several things:

-It requires less meal prep and/or thinking about what I am going to eat since I am only doing 2-3 meals per day, with at least one of these being Huel.
-I don’t feel like I am constantly eating all day long.
-When I do eat, I am eating enough to feel full and don’t crave more immediately afterwards.
-It has not been as difficult as expected to not eat until lunchtime each day; often I simply drink more water which is good for me anyways!
-MOST IMPORTANTLY, it has been so, so much easier for me to not overeat and to stay below my daily calorie goal each day! Eating my first FULL sized meal at lunch (often a Huel shake with a side of veggies) allows me to feel satisfied until dinner, when I eat again. Then I am good until the following day. My BIGGEST struggle in the past with multiple small meals per day was wanting to eat more immediately after each small meal, and exceeding my daily calorie goal.

I see intermittent fasting as something I can stick with long-term, and it is already paying dividends for me.


OK, I can see why this MSMAD plan might be useful in this type of situation. Take, for example, someone who has been overweight for a long time and is clearly indulging in a serious calorie surplus. They might consume two very large meals a day, totaling around 4 or 5 thousand calories. And because of this, their stomach feels full most of the day. To ask them to go without a meal for a 16 hr period, or even 12 hours, might be too far of a stretch. They are mentally conditioned to always feels full and therefore might overreact. So for them, suggesting a system of 250 - 300 calorie meals, 6 per day, spaced out during wake times, might be a good option. They get the benefits of having something in the gut most of the day, and don’t have to wait too long till they eat again and can therefore stay on the regimen. At the end of the day, they eat 6 meals but it’s only 1500 - 1800 calories, a major reduction from their 4 thousand. Or whatever number you want to adjust to. Olive branch extended.

However, we must both agree that this person didn’t just reduce calories. He also reduced the total amount of insulin his pancreas made. By a big margin.

Your statement “losing fat mass has to come from a negative calorie balance” is technically true. Yes. Much in the same way that gravity is the immediate cause of a plane crash. Both are true, but don’t really delve into the source of the problem.

The limitation of thinking about losing fat mass and negative calorie balance is that many people will assume that the body handles carbohydrates and fats the same, which it most definitely does not.

The body will not burn fat for energy until insulin levels fall to lower levels. If insulin is high enough, the body’s cells will preferentially burn carbohydrates. If high enough, the body will burn carbs almost exclusively for energy and will store almost all incoming fat from the diet, and fat will not come out of adipose tissue. No fat loss will happen if insulin levels are kept chronically elevated. This is not controversial. This has been universally accepted by the medical community and proved in animal/human studies for many decades.

We read food labels and read the total calorie content. This is a mix from all 3 macronutrients. And we can even estimate a person’s calorie intake, where we mix all 3 macros. So, if we know that the body’s usage of carbs verses fat depends highly on hormones, particularly insulin, is it fair to measure calories in verses calories burned in an overweight patient? If dietary fat invokes almost no insulin response and carbs invoke a strong insulin response, might measuring total caloric intake be flawed? Shouldn’t we focus more on carbohydrate intake? If the goal of an overweight person is to preferentially burn body fat, and that cannot happen until insulin is low, then shouldn’t we focus on trying to help our patient lower his insulin and not so much on calorie consumption verses calorie burning? One last question to ponder: when is a person’s insulin levels the lowest he/she can possibly go (besides being type 1 diabetic)? In a person who does not have TYpe 1 diabetes and their pancreas makes insulin, when are their insulin levels at the lowest possible (and therefore the body is burning as much fat as possible)? You know the answer. During fasting.

(And this is one of the uses of the glycemic index. It directly measures blood glucose after eating a food. But what we are really measuring is the person’s insulin response. The ultimate purpose of the glycemic index is to get a surrogate measure for how much of an insulin response will you have from eating this particular food.)

I have more to write, but my break is over. I will address this issue of “overeating”. For now, let me say that the testimonies of many people who have practiced IF have shown that we do not overeat. If anything, i have a hard time getting myself to eat enough.

It’s going to be much easier for me to fast, than to eat many little unsatisfying meals.

I’ve also read that the body will only process around 30ish grams of protein towards muscle repair at a time.

Maybe go MSMAD on cardio days, and IF on weight days…

In regards to the fear of overeating when practicing a fast, yes this is possible. Some people may experience this when first attempting an IF routine. But overall, the testimonials from people in the fasting forums or social media groups or vlogs on YouTube suggest that many many people do not “overeat” during their feeding window. Yes they do eat more per meal than a smaller meal on a MSMAD plan. But total daily caloric intake is not too much. In fact, their total caloric intake was actually less than what they were intaking before. The net effect is still a calorie deficit … Which is to say a net reduction in total daily insulin.

In general, calorie reduction is a surrogate for insulin reduction. Insulin reduction promotes more fat mobilization from adipose tissue and signals the cells to use more fat for energy.

The same can be said about the glycemic index and load. All things considered equal, substituting a low GI food for a high GI food will cause a lower insulin response when eaten in the same amounts. GI and GL are surrogates for insulin response to a meal. Lower insulin means your body spends less time in fat storage mode and less time in carbohydrate burning mode. Lower insulin allows fat to become more mobile out of adipose tissue.

About 6 hours after a meal is consumed and digested, insulin levels begin to fall. (Smaller meals or meals with lower GI/GL shorten this time). The body begins to go the opposite route of what it was doing during the digestion and nutrient storage phase. The liver now begins to break down glycogen to release some glucose to the blood stream. Adipose now begins to ramp up hormone sensitive lipase to mobilize fat out of adipose and into the blood stream, available for tissue to uptake and use for fuel. The longer a person goes since their last digested meal, the lower insulin goes and the more fat is mobilized. The more glycogen is depleted. As long as the person is not taking any diabetic meds and has no other hormone abnormalities, his blood sugar will not drop too low. The body will adjust and use more and more fat for fuel, reserving the glucose for the brain. In times of prolonged fasting the liver can even use molecules like glycerol (from the triglycerides broken down) to make some glucose. In a person with a lot of extra body fat, he can theoretically do this for many days or even weeks, with no ill effects. The only reason he cannot get to this point is because of habit and because he keeps re-spiking his insulin levels with food. If he were to endure the mental sensations of skipping his normally-scheduled meal, he could more readily transition into this fasted state of body fat mobilization. Instead, he continues to eat soon after the last meal was already digested and just before his insulin levels fall low enough to allow for fat to come out of adipose, he then halts this by eating again.

MSMAD is ultimately flawed in most people because it doesn’t allow enough time of the day to stay in fat mobilization mode. The person remains in fat storage and carbohydrate burning mode. If the ultimate goal of the fat person is to lose body fat, he should preferentially stay in fat burning mode as long as possible, which will only occur when his insulin levels are lower. IF accomplishes this very effectively. Ketogenic diet can do this pretty well. Eating a lower GI/GL meal can lower insulin verses a high GI/GL meal. Eating MSMAD may or may not reduce total daily insulin a little, depending on what the person was eating before. Exercise can improve insulin sensitivity, lowering the amount of insulin needed when you do eat. Combining some of these above will yield better results.

It’s a matter of what is best for each person. Keto plus exercise. Low GI plus exercise. IF plus low GI meals. MSMAD with low GI foods with exercise. But in the end, we must all agree that the lowest insulin can go is during a fasted State. So, theoretically, IF should allow more time for fat burning and therefore theoretically be the most ideal way to shed extra body fat, so long as the person does not consume rediculous amounts of food during the feeding window and therefore raise his total daily insulin (which testimonials have shown doesn’t happen in most).

Observation: There are dozens of forums and social media groups dedicated to IF. I just don’t see the same for MSMAD. in the end, IF is more convenient more effective than MSMAD. The only barrier is psychological.

And now the final Olive Branch. The convenience of Huel and the low GI of Huel would make it the best option for MSMAD, should one choose that route. Of course, Huel can also be used for people who practice IF or for people who do neither.

But that’s the beauty of Huel. It can be used by so many people. People who want to practice IF or MSMAD. It can be used by vegans and omnivores. It can be used for people who want to gain or lose or maintain weight. It can be done as entire meal intake each day or just one meal a day at work 5 days a week. It can be for people who like to add stuff and blend or the RTD for people who ain’t got no time in the morning to prep. it can be used pre-workout or post workout. Some people use it as the first meal of their day to break their fast, whereas some people use it as the final meal before they fast. It can be made sweet or bland. It can be used by health conscious people or people who don’t want to be bothered by nutrition labels. It can be used by Democrats and Republicans. It is the great uniter.

Except keto. You keto people aren’t included. Sorry, nothing personal. You know… Oats.

1 Like

My concern with IF is when the fast overlaps a long session of high intensity interval training cardio.

I can mountain bike for a couple hours on an empty stomach no problem, but is there a point where the body will attempt to break down protein stores (lean muscle mass) in order to meet the high energy demand?


This is a fairly complicated question and I may not be the best person to answer this. My self study of IF mostly relates to body fat loss and the effects on insulin. But I can kind of weigh in on this.

In my readings and study of IF from Thomas DeLauer and Dr. Jason Fung, in their books they do address the concern of muscle loss during IF or prolonged fasting. DeLauer says that during a fast, Growth Hormone (GH) levels rise slightly (I think they also rise a little during sleep). From what I read about GH, it has a “muscle sparing” effect. It’s effects are complex but it tends to inhibit muscle breakdown. Dr. Jason Fung also addressed this issue in one of his videos. He says that the body will not break down muscle for fuel during a fast, unless the person has become severely depleted in his fat stores. He says this is nonsensical. He likens it to an analogy of people burning their couch in the fireplace instead of the stored firewood to keep their house warm. He says that the body has stored fat for energy and that once insulin levels fall this fat will mobilize and be readily available for energy. Humans would have died off as a species if our bodies broke down our muscle (which we need to move, find food, and survive) and just neglect our stored fat. Gary Taubes (“Why we get fat and what to do about it”) also echos this mechanism. In his book he describes the science behind fat mobilization during periods of low insulin to be available for energy.

Look, during fasting, insulin is low. What this means is that most cells in the body will go into their default mode of burning fatty acids as their main source of ATP energy. Most of the cells in our body will only burn glucose for fuel if told to do so by insulin. Only neurons absolutely require glucose. From what I have ready the brain requires about 5 grams of glucose per hour to function and this does not increase based on physical activity. 5 grams of glucose is about 1 cracker’s worth of starch broken down, or a few pieces of skittles. Per hour. Our body absolutely requires only 5 grams of carbs per hour to live. And I have also read that during a prolonged fast where the body is in ketogenesis, the brain can utilize some ketone bodies for fuel and its glucose requirements drop to like 3 grams per hour. Again, this need for carbs seems to be independent of your physical activity. Exercising muscles can easily use fatty acids to make ATP. And, let’s say that you were going HAM and needed some of the muscle’s glycogen and depleted that, your muscles would probably become tired and you would naturally slow down to the point where you didn’t need to use any muscle glycogen anymore.

The process of gluconeogenesis is used by the liver in times when its internal glycogen supplies are depleted and we haven’t eaten carbs in a while, so it needs to make the necessary 5 grams of glucose per hour to live. Yes, it can use some of the amino acids from broken down proteins to make glucose. But one of the non-carbohydrate substrates that the liver can use to make glucose (if needed), is glycerol. Glycerol can come from broken down triglycerides. 3 Free fatty acids are packed with a glycerol to form a Triglyceride. Triglycerides cannot pass through cell membranes. So this is the storage form of fat. The lipoprotein lipase and hormone sensitive lipase enzymes inside and outside of cells (or in the cell membrane itself) take apart and put together the triglycerides to either mobilize or store fat. Hormones (especially insulin) control the levels of these enzymes and thus influence fat to be either mobilized or stored. When fat is mobilized for energy, the leftover glyceride molecule can be used for gluconeogenesis in the liver. This is perfect. In times of prolonged fasting when fat is mobilized to make energy, this leftover glycerol is available to make glucose (if need be). No need to break down muscle into amino acids and convert those to glucose. More sense to use glycerol. And this is what I think happens.

(It should be noted that exercising muscles readily uptake glucose and fat by their own internal mechanisms, independent of hormones. Yes, one way diabetics can temporarily lower glucose after a meal is to do a short stint of exercise. Muscles uptake nutrients independent of insulin during exercise, and as such the pancreas senses this drop in glucose and tapers off its insulin production.)

So to directly answer your question, yes at some far reaching point into the fast when you are emaciated and have gotten down to a good 3% body fat, and you have no more stored fat and glycerol to use… sure, your body will break down muscle to make energy to try and save your brain and heart. You will be completely tired, hungry AF, and in a very bad state. Take me, for instance, with my BMI of 23. If I were to eat nothing for a month, at that point I would start losing serious amounts of muscle to gluconeogenesis.

Our bodies are smarter than this. None of us could actually push ourselves to the point where we physically exerted ourselves in a fast to get to the point of losing muscle just to meet energy needs. We would slow down, become super hungry, or just stop altogether. This, IMO, is not even an issue you need to worry about. IF is not causing muscle wasting. It is causing fat wasting. You’ll be perfectly fine.

Thomas DeLauer purposely exercises in the fasted stated and that dude is jacked. Check out his vids on YouTube. IF doesn’t seems to make him waste muscle.


That explanation makes sense. I am well aware of the “wall” I hit around the 2-3hr mark where performance drops to a level that makes all but the easier mountain biking trails unsafe. So I’ve learned the hard way to back off and call it a day.

Thank you all so much for taking the time to put your thoughts and knowledge down for folks like myself that are wanting to better understand the science behind it all.

1 Like

Hey, if I can help even one person come to a better understanding of fat regulation and how it relates to body fat loss, then it’s well worth it. Remember I am coming from a BMI of 38.5 many years ago. So I know all well the struggles of body fat loss as well as the benefits of losing it. I used to exercise 2 - 3 hours every day and got some success but ran into a wall (figuratively speaking). And then I could not maintain that long term. Got upset when I had to keep eating so much and thought I could “out-exercise” my eating to lose weight. I wish I had known about the endocrine model and 2-compartment model of body fat regulation years ago. Could have saved myself a lot of time and cognitive dissonance.

That term cognitive dissonance, trying to hold two opposing viewpoints in your brain at the same time, is one of life’s most frustrating things. The one-compartment model (a.k.a. simlified calories-in-calories-out) model had me thinking about the problem the wrong way. I was acting on its principals, but the evidence right in front of my mirror and scale contradicted this belief.

I wish I had discovered something like Huel years ago. I wish someone had made vidoes about IF years ago. I wish I had learned about the Glycemic Index/Load years ago.

And to bring this back to the original post in this thread: I just want to re-iterate how useful the glycemic index is in helping people learn about why we might be getting fat. It falls in line with the endocrine model of body fat storage. It quantifies the carbohydrate portion of a food and gives an easy estimate for how much insulin your pancreas will be making if you eat xx amount of this food. (Albeit, this is a bit oversimplification of the GI, and actual insulin release depends on a person’s insulin sensitivity.) It is an easy tool to help people make better food choices.

Interestingly enough, I suspect the old “point system” of Weight Watchers is at least partially based on the glycemic index and glycemic load of the food. I remember my sister had great success with WW and this point system was easy to follow. She noticed that foods/meals with higher fiber content had lower points and the system seemed to encourage her to eat food that was a lower glycemic index and higher in fiber. I do not know if current WW online or app rates food on this point system or if they’ve gone to something more “modern”. Well, modern or not, points or GI, whatever you want to call it, the science remains the same.


I think this conversation thread is spectacular with lots of good information. I have a question though. What does it exactly mean to have a good/fast metabolism in relation to the explanations above? I’ve always heard MSMAD could improve your metabolism. I’ve never been a fan of MSMAD. I like the idea of fasting just because it is more convenient. I’m just curious as to the reasons/causes behind having a fast metabolism in relation to the “low insulin burns fat” scenario. What affects someone’s metabolism at a young age when they eat crap and stay thin/healthy versus when they get older and suddenly start getting fat without changing eating habits?

1 Like

I don’t think it has much meaning. From what I understand, metabolism is a very dynamic thing, fluctuating throughout the day, fluctuating from day to day, and interdependent on many factors. I tend to think of metabolism an effect and not a cause. Hormones are really more the cause and then our metabolism is the result of the various hormone levels and tissue sensitivity to these hormones.

For example, people who embark on a 7 day fast report they feel more energetic starting on day 3. By that time insulin has dropped to baseline low levels. And certain counter hormones, like human growth factor, glucagon, and nor-epinephrine rise a little. Hormone-sensitive lipase is then able to be expressed inside the adipose tissue and free fatty acids are able to come out of adipose much more readily, making them available for the various tissues to burn for ATP. (High insulin suppressed hormone-sensitive lipase). The liver begins to make some ketone bodies from some of the fatty acids, which help supplement energy for the brain and suppress hunger. Ketone bodies may also cause the brain to feel more focused. (Possibly a survival mechanism to help ancient man feel focused so he can go find food , since indefinite fasting will eventually lead to death.) Norepi can help raise our sympathetic nervous system which helps us feel more energized and focused. Growth hormone helps keep the body’s lean mass from breaking down and helps direct the body to utilize fatty acids for energy and not chop up our proteins for energy. And I am sure there is host of other changes that occur. But in this example, the hormonal changes from a prolonged fast are the cause of the person’s metabolism going up. Well, at least for a period of time. Eventually when the fat stores and other nutrient recycling becomes depleted, the person’s metabolism will slow down. Fasting can only be maintained for as long as you have the long-term stores to do so.

Insulin resistance occurs gradually over time and is related to the food we eat and the level of physical activity we do, and to some extent the timing of food. You ask “What affects someone’s metabolism at a young age when they eat crap and stay thin/healthy versus when they get older and suddenly start getting fat without changing eating habits?” Because insulin resistance is insidious and takes years to develop. Young people don’t have the signaling problems of insulin resistance. Their muscle, fat, and liver cells respond properly to insulin and deal with the influx of glucose from the meals. But years of eating food high in saturated fat, cholesterol, trans fat, and processed sugars cause the liver and muscle cells to become deaf to insulin. Those tissues down regulate their response to insulin. So now, at middle age, when the person eats a meal the pancreas has to compensate and release more insulin to try and make the liver and muscle cells do what they are supposed to do after a meal. Since the fat cells remain more sensitive to insulin, and insulin tells fat cells to store fat, this exaggerated insulin response causes us to fatten.


Yeap I agree with Deron. Over the course of long periods of time (weeks and months) metabolism isn’t important for the majority of the population as it will even out and your body will compensate. The main link with metabolism is weight. Contrary to what you might think the more you weigh the higher your metabolism. This is why as you lose weight you can experience plateaus in weight loss and find it more difficult to lose weight as you get further into your weight loss plan.

Unless you have a condition such as hyperthyroidism then metabolism is not something that should be high on your list of priorities - focus on calorie intake however, you may achieve that.