According to the official nutrition guidelines, carbohydrates are the “king” of foods. They’re supposed to be the “energy food” of choice, they’re supposed to be the source of all the energy we need and they’re supposed to be the major source of calorie intake. Yet, the majority of us are told to eat more, eat less, cut carbs, or eat the same amount of carbohydrates but in different forms. The science is there, but the myth seems to have gotten in the way.
It’s no secret that weight loss can be a complicated and convoluted process, but that doesn’t mean it can’t be simple. In fact, it can be far more simple than most people realize. Successful weight loss doesn’t depend on complicated dieting plans, expensive pills, or invasive surgery. Instead, it depends on a little bit of knowledge, and a little bit of discipline.
Some experts – and many people on Twitter – believe that carbs and insulin cause weight gain. But according to them, the situation can be easily remedied: When you follow a low-carb diet, you keep your insulin levels low and lose weight quickly. All without worrying about calories. Here we will examine the scientific basis for these claims and attempt to answer the most important question on everyone’s mind: What really makes the biggest difference in fat loss?
Pasta was once considered a healthy food.
But over the past two decades, carbohydrate phobia has increased dramatically.
What’s next? Pasta is known to be quite fatty.
When people want to lose weight, they are often advised to give up rigatoni, rotini and ravioli – as well as rice, potatoes, bread and even fruit.
Reason: Of course, carbohydrates… and the hormone insulin.
All of this is based on a controversial hypothesis known as the carbohydrate-insulin model of obesity.
From 30,000 feet, it looks like this:
- They eat carbohydrates.
- Your body secretes insulin.
- Then, according to the model, insulin 1) prevents the body from burning fat for energy and 2) distills fat and sugar from the bloodstream into fat cells.
- All of this causes your body to think it’s hungry, which leads to a slower metabolism and more cravings.
This is a very simplistic explanation of why we still have a growing obesity problem in the world.
And many proponents of the carbohydrate insulin model claim that it leads to a perfectly simplified solution: Switching to a low-carb diet.
With this approach, they say, you create a hormonal environment that gives you a metabolic advantage that allows you to effortlessly lose fat by consuming as much as you want.
You don’t have to worry about calories and portion sizes.
Question: Has this been scientifically confirmed?
In this article, we explain how the relationship between carbohydrates and insulin works – both for health and fat loss – and answer these questions:
(Warning: we’re going deep, so you may want a cup of coffee).
(If you want to see the authors discuss this article in more detail, watch the video below. Otherwise, just scroll down in the video player or click here to go to the next section).
FN Coaches Round Table : Robin Beyer discusses the truth about insulin, carbs and weight loss with Helen Colias and Brian St. Clair. Peter.
Insulin and carbohydrates: Partners in crime?
To fully understand the carbohydrate-insulin model, you have to start with the biology. (Read at your own risk!)
Here we go…
If you eat certain carbohydrates, such as. B. starch and sugar, they are quickly broken down into glucose and absorbed into the bloodstream. It increases the sugar level in the blood. (Also called blood sugar).
The more carbs you eat, the higher your blood sugar immediately after eating.
However, your body tends to regulate your blood sugar levels carefully.
Have you ever tested your fasting blood sugar? You probably know that the normal range is between 70 and 100 mg/dL.
Your body strives to maintain these blood sugar levels so that all systems remain healthy and function optimally.
(For example, chronically high blood sugar causes inflammation that can damage blood vessels, kidneys, eyes and nerves. Therefore, diabetes can lead to many complications).
When you eat carbs and your blood sugar rises, your body – specifically your pancreas – releases insulin. Insulin is the main regulator of blood sugar levels.
Normal blood sugar response after eating 75 grams of carbohydrates.
Insulin is needed to transport glucose from the blood to muscle and fat cells, where it can be used for energy or stored for later use. 1
Without insulin, blood sugar levels would remain high for much longer. And that would be a shame. Therefore, people with type 1 diabetes must take insulin daily via injections or a pump.
Conclusion? As blood sugar rises, so does insulin.
And don’t forget it: When you eat a lot of carbs at a meal, your blood sugar and insulin levels rise more than when you eat fewer carbs.
Context also plays a role. People react differently to the same amount of carbohydrates, depending on many factors (2,3,4):
- Body Fat
- Health of the microbiome
- Muscle mass
- The timeliness, energy and duration of the sport.
- Time of day
- What else do they eat (for example, fats and fiber, another type of carbohydrate, can slow glucose uptake and weaken the insulin response, while some proteins can strengthen the insulin response).
As a general rule : The leaner and more active a person is, the more sensitive their cells are to insulin. (This means they need less insulin to remove glucose from the blood.
This is one of the reasons why people with a healthy lifestyle can tolerate carbohydrates better than sedentary people. In fact, they generally need more carbohydrates to improve their performance and recovery.
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Why insulin can be a problem
As mentioned earlier, glucose and insulin go together when your body is functioning normally. When the blood glucose level rises, enough insulin is released to bring the blood glucose level back within the normal range.
However, it is also possible that there is a scenario where there is too much insulin. It is thought that this happens when your cells become resistant to insulin, a condition called insulin resistance, a precursor to type 2 diabetes.
Insulin resistance requires more insulin to deliver the same amount of glucose to the cells. And because the condition worsens over time, insulin levels can remain high even when you haven’t eaten. (This is called hyperinsulinemia).
We don’t know exactly why insulin resistance occurs. It is assumed that this is caused by chronic high fatty acid levels in the blood.
(Insulin resistance is also associated with a number of factors, including genetics, ethnicity, sleep, exercise, smoking habits, etc.6,7,8).
Obese people, especially those with large amounts of visceral fat (deep fat in the abdomen around various vital organs), are known to be more prone to insulin resistance.
We also know that losing excess body fat often solves the problem of insulin resistance.
Now that you know the story, let’s go to the first question…..
Does insulin affect fat burning?
Not really. Insulin, however, affects the rate of fat burning in the body.
In addition to insulin’s role as the main regulator of blood sugar, it is known that
Insulin inhibits lipolysis.
During lipolysis, the accumulated fatty acids are transported from the fat cells to the bloodstream, where they can be used for energy production.
When this process is inhibited – as is the case with high insulin levels – fewer fatty acids are available as fuel for muscles and other metabolically active tissues. This is why many people associate insulin spikes with shutting down the body’s ability to burn fat.
Insulin stimulates lipogenesis.
During lipogenesis [lie-POE-jen-uh-siss], fatty acids are transported from the bloodstream to fat cells, where they are stored for later use. This is often called a fat storage diet, which most people try to avoid.
In addition, lipogenesis can also result in the conversion of carbohydrates to fat and their deposition as fat (called de novo lipogenesis or DNL). However, it is important to note: DNL occurs in significant amounts only in the presence of a general excess of carbohydrates and calories. (That is, you constantly eat more calories than you consume.9)
From all these effects we can conclude that insulin is a real problem for fat loss.
So it’s worth saying:
The purpose of insulin is not to make you fat.
Insulin suppresses lipolysis because you just ate nutrients, especially carbohydrates and/or protein. And it’s more efficient for your body to use incoming nutrients to produce energy than to release stored nutrients to produce energy.
Think of it this way: If you have $100 in your pocket and you want to go shopping for $25, you don’t go to an ATM to get extra cash. You would use the money you already have in your pocket.
Similarly, why would your body release stored fat into the bloodstream for energy when it already has plenty of energy?
Moreover, at any given time, there is a complex interaction between hormones and enzymes that can counteract, limit, or enhance the effects of any chemical, including insulin.
While z. B. Insulin suppresses lipolysis (fat burning); other hormones acting at the same time stimulate lipolysis.10 Examples:
- Growth Hormone
Furthermore, insulin stimulates lipogenesis (fat deposition), while other active hormones – leptin, growth hormone and highly elevated cortisol – inhibit lipogenesis.11
These hormones do not completely disappear from the body in the presence of insulin. They also perform important work and can modulate the action of insulin.
For example, although carbohydrates are the main macronutrient influencing insulin secretion, protein also significantly stimulates insulin secretion.12,13 Nevertheless, protein is believed to have a positive effect on improving body composition.
Some suggest this is because the protein also stimulates the production of the hormone glucagon, which nullifies the effects of insulin.
In any case, the effect of insulin on metabolism is not clear: It is influenced by many other factors. (For another example of this phenomenon, see the article FGF-21: the secret metabolic hormone below. You can also skip this box – or click here to continue with the main article).
FGF-21: The metabolic hormone secretes
It is clear that insulin is a key mechanism in the carbohydrate insulin model.
But how can this mechanism be supported without conclusive clinical evidence from controlled trials (more on this later)?
Answer: It is important to understand how all the other hormones and metabolic processes work together.
Otherwise, the model cannot reliably predict what will happen in a given situation. This makes… incomplete and therefore an unreliable model.
Thus, the natural progression of type 2 diabetes is accompanied by a decrease in insulin levels over time.
Based on the carbohydrate-insulin model, people who have had type 2 diabetes for many years should have an easier time losing weight than people with pre-diabetes.
But we don’t see that. If you’ve had type 2 diabetes for a few years, the weight doesn’t suddenly disappear.
If we do not understand why this contradiction occurs, what confidence can we have in the accuracy of the carbohydrate-insulin model?
The reality is this: You may not want to consider insulin alone. There are many other hormones involved in fat loss, appetite, hunger and metabolism – many of which are not well understood.
Take fibroblast growth factor 21 (FGF-21) for example. It is thought to be a key regulator of whole-body metabolism and energy homeostasis, but you rarely hear anyone talk about it.
Studies show that FGF-2116,17 :
- Reduces appetite
- Decreases the rate at which carbohydrates are burned for energy.
- Increases the rate of fat burning for energy
- Improves blood sugar control
- Increases the activity of brown fat (type of metabolically active fat)
That’s a pretty strong summary.
Interestingly, excessive consumption of carbohydrates increases FGF-21, whereas excessive consumption of fat does not.18 And under certain circumstances, FGF-21 can override insulin to stimulate lipolysis (fat burning).19
This does not mean that FGF-21 is the secret to fat loss. (There is no mystery.) But to ask a question: How does FGF-21 fit into the carbohydrate-insulin model?
It’s not clear now. And that could mean that the model is defective.
Instead of seeing the action of insulin – or any of these hormones – as an on/off switch, see it as a switch.
Your body is constantly adjusting its hormones, not only based on food intake, but also due to thousands of other factors and processes that you may not even be aware of.
Summary: When insulin levels are high, you burn less fat for energy than when insulin levels are low. But you won’t completely stop burning fat.
Instead, you prefer to burn carbohydrates for energy.
The real question is not whether insulin interferes with fat burning. Does insulin interfere with fat breakdown?
This is what we can say with certainty: There is no scientific evidence that you will gain weight if your energy intake is lower than your energy expenditure. (Short-term water changes in the body are obviously not included).
Or to put it another way: Insulin itself does not cause weight gain. You also need to consume more calories than you expend.
Remember that in healthy people, the rise in insulin levels after a meal lasts only a few hours. It then returns to baseline, which in turn accelerates fat burning.
When energy intake is lower than energy expenditure, insulin remains low for long periods during the day and night. This allows fat burning to continue at full force, despite short periods of fat burning inhibition.
So when you start a diet to lose fat, you can do it with or without carbs20. (Studies comparing the effectiveness of different diets are discussed later).
Does insulin make you hungry?
One of the key points of the carbohydrate-insulin model: High insulin levels, as a result of a high carbohydrate diet, cause you to eat more.
But the evidence for this claim is weak.
The premise is this: When insulin signals the body to store fat, it clears the bloodstream of fatty acids and glucose and directs them to the fat cells.
There is a hypothesis that this causes what is called internal starvation.
By depriving your blood of these fatty acids and glucose, your brain thinks you are hungry. And that in turn encourages you to eat more.
But do fatty acids in the blood really decrease?
As Stefan Guienet, PhD, notes, studies show that obese people have normal or even high levels of fatty acids in their blood21,22,23,24.
In addition, insulin has long been thought to help regulate appetite.25 Animal studies suggest that high levels of insulin in the blood signal the brain to reduce food intake. (This phenomenon has been studied directly in primates, but not in humans).
So in this model, the increase in insulin reduces the urge to eat.
But as with fat burning and storage, insulin is not the only hormone involved in appetite regulation. Others are26 :
- Cholecystokinin (CCK)
- Glucagon-like peptide 1 (GLP-1)
And these are just a few of them.
Summary: The regulation of hunger and appetite is incredibly complex.
It’s not as simple as reducing insulin or regulating a single factor.
Which brings us back to the original question: Does the hormone insulin make people hungrier?
There is no conclusive physiological evidence that this is the case. In fact, a new, highly controlled study, discussed later in this article, contains data that contradicts this claim.
Moreover, competing mechanisms strongly suggest that other factors, such as. B. the hormone leptin, could be much more important than insulin. (To learn more about the role of leptin, read this article: Are you eating too much? It’s your brain’s fault).
Does insulin decrease metabolism?
Metabolism is highly dependent on body size. People with larger bodies generally have a higher resting metabolic rate than people with smaller bodies.27
Therefore, when a person loses weight, their metabolic rate decreases. However, this reduction is generally even greater than would be expected from changes in body weight alone.27
This is called metabolic adaptation (which is also largely determined by leptin) and may be one reason why it is difficult to sustain weight loss. Your body needs fewer calories to maintain your new weight than someone who has been the same weight for most of their adult life.
According to the carbohydrate-insulin model, carbohydrate-rich diets and high insulin levels are responsible for this metabolic adaptation.
Hypothesis: As insulin moves fatty acids from the blood into fat cells and away from more metabolically active tissues, such as… B. Muscles, pipes, the result is a lower metabolism.
However, this contradicts research showing that insulin increases the absorption of fatty acids in the muscles28.
On the other hand, the hypothesis suggests that low-carbohydrate diets provide more fuel to metabolically active tissues because of their hypoglycemic effect. It keeps the metabolism going, like throwing wood on a fire.
This is what proponents of the carbohydrate-insulin model call a metabolic advantage.
But is that really the case? Does a low-carb diet really increase your metabolism compared to a high-carb diet?
Let’s see what human studies can tell us.
What does the research say about nutrition and metabolism?
The most detailed study on this topic is a 2017 meta-analysis by Kevin Hall, PhD, of the National Institute of Diabetes and Digestive and Kidney Diseases (NIH Institute)27.
The researchers reviewed 32 controlled feeding studies that directly compared low-carb and high-carb diets and their effects on daily energy expenditure.
A calorie-comparative, controlled diet means that both diets contain the same number of calories and the researchers provide all the food to the participants.
These studies also compared the amount of protein in different diets.
This is important because proteins require more calories for digestion (25-30%) than carbohydrates (6-8%) and fats (2-3%).29
When the diet contains a significantly greater amount of protein, energy consumption is likely to be higher, regardless of the amount of carbohydrates consumed.
What do the data show?
Energy expenditure was 26 calories per day higher with the high-carbohydrate diet than with the low-carbohydrate diet.
However, this conclusion has been criticized by David Ludwig, MD, PhD, one of the leading proponents of the carbohydrate-insulin model.
Only four of the 32 studies lasted at least 2.5 weeks, and according to Dr. Ludwig, the body needs two to three weeks to adapt to a low-carbohydrate diet, also known as fat adaptation.14,30,31,32,33
Currently, there is no proven method to objectively determine whether someone is fit for fat. So it could be more than two weeks, but no one knows if it is, and no one can say how they will know when it is.
However, proponents of the carbohydrate insulin model often cite the results of a 20-week study conducted by Dr. Ludwig’s group following Dr. Hall’s 2017 meta-analysis34 to support their claim.
A revolutionary study?
In a 2018 study, Kara Ebbeling, PhD, Dr. Ludwig and her research team asked study participants to initially lose 10.5% of their weight on a 45% calorie and carbohydrate restricted diet for 9-10 weeks. Those who successfully completed the diet then followed a maintenance diet for 20 weeks:
- Low carbohydrate content (20%)
- Moderate amount of carbohydrates (40%)
- High carbohydrate content (60%)
- Participants in the low-carb diet consumed 278 more calories per day than participants in the high-carb diet.
- People on a moderate carbohydrate diet burned 131 more calories per day than people on a high carbohydrate diet.
- It is also worth mentioning that the participants already lost an impressive amount of weight before switching to a low-carb diet. In the first 9-10 weeks, they lost an average of 21 pounds while consuming 45% of their calories as carbohydrates.
At the time, this was the best evidence to date that low-carb diets can provide significant metabolic benefits. (Continue reading the latest study).
But it has also been questioned by Dr. Hall and other experts who have questioned the measurement and reporting methods used and the statistical analysis.
And because the study participants lived in their usual environment – not in a laboratory – it’s possible that not all the foods they ate were taken into account.
There’s also this: If low-carb diets have a metabolic advantage, people should lose more fat than with high-carb diets. Dr. Hall’s meta-analysis did not show this. In fact, the opposite was true (by an insignificant amount).
But let’s dive deeper into the research.
Do people on a low-carb diet lose weight?
Yes? You don’t? Maybe? Sometimes?
In many studies, from several weeks to several months, low-carb diets were often better than high-carb diets.36,37,38,39,40,41
But does it specifically relate to metabolic advantage? Or do low-carb diets have other benefits?
A popular and logical explanation is that people on a low-carb diet eat fewer calories than on a high-carb diet.
Most studies showing that a low-carb diet leads to greater weight loss are not studies using a protein- and calorie-controlled diet.
Instead, they often provide participants with dietary recommendations and meal plans and advise them on what to eat, but do not monitor their food intake.
This is a disadvantage for observing the specific effects of each regime. But it can be positive when you look at how these diets work in everyday life.
After all, that’s the way the average person follows a diet.
Why would a low-carb diet cause people to eat less? There are several possible reasons:
- Higher protein intake increases satiety and reduces appetite.42
- The limited food choices allowed them to avoid hundreds of highly processed, high-calorie foods that they would have otherwise eaten, such as B. cookies, muffins and chips, and make way for more nutritious, high-calorie foods like vegetables.
- Limited food choices can also lead to sensory satiety. In other words, if you eat the same foods over and over again, they may become less appealing and you will want to eat less of them43.
- Liquid calories-soda, fruit juice, even milk-are generally banned, so most calories are consumed in solid foods, which are more satiating.44,45,46
- Increased blood ketone levels, which increase with carbohydrate restriction, may contribute to appetite suppression47,48,49.
This all sounds pretty perfect (but that’s just speculation).
There’s a problem, though: As with other diets, a low-carbohydrate, energy-restricted diet will also fade in belief over time. So much so that after one year, weight loss (and fat loss) is generally negligible or not significantly different between low-carb and low-fat diets39,40,41.
(In addition, 12-month studies of low-carbohydrate, low-fat diets show that participants switch to a more balanced diet over time.)
This is not an indictment of low-carb diets. On the contrary, it seems that most people find it difficult to maintain a restrictive approach to eating for a long period of time.
But while these studies give us an idea of what happens in an open habitat, they do not provide a deep understanding of what happens physiologically under tightly controlled conditions.
The best research we have on the subject? Two studies conducted by Dr. Hall in the Department of Metabolism will be published in 2016 and 2020, respectively31,50.
Gold Standard Compliance
The Metabolic Neighborhoods Study requires participants to remain in place throughout the study. This makes it the gold standard in human nutrition research.
The first study was conducted as follows31 :
- 17 male participants lived in the metabolic unit for two months. Everything they ate and how they lived was under strict control.
- First, they followed a high-carbohydrate diet for 4 weeks.
- They then followed a very low-carbohydrate ketogenic diet for 4 weeks.
- Calories and protein were the same for both diets. Only carbohydrates and fats were increased or decreased.
- The diets produced a negative energy balance of 300 calories per day.
- Each participant was required to exercise on a stationary bicycle for 90 minutes per day to ensure a consistent and uniform level of physical activity.
If the carbohydrate-insulin model were correct, these are the results one would expect:
- Reduced insulin production during the low-carbohydrate phase.
- Significant increase in energy consumption during the low-carbohydrate phase.
- Fat loss is greater on a low-carb diet than on a high-carb diet.
What the study showed
|Low carbohydrate (high fat) content||High carbohydrate content (low fat)|
|Insulin||People produced 22% less insulin during the day.||No change in insulin production|
|Power consumption||Increase of 57 (+/- 13) calories per day||No measurable effect|
|Weight Loss||Average weight loss of 4 pounds, of which 1.16 pounds was body fat.||Average weight loss of 3 pounds, of which 1.29 pounds was body fat.|
What does this mean?
- People lost the same amount of weight and fat (statistically) with both diets.
- Although a low-carbohydrate diet produced less insulin in the subjects, it did not lead to significant weight or fat loss.
- A small increase in daily consumption was observed, supporting the idea that low-carbohydrate diets may provide a small metabolic benefit during weight loss.
Research on extreme regimes
A more recent study, scheduled for publication in May 2020 (and not yet formally subject to peer review), takes a slightly different approach and provides new insights worth exploring50.
Again, the researchers compared low-carb and high-carb foods. But this time, they looked at even more extreme diet options.
- Low-carb animal diet (also known as ketogenic diet)
74.6% fat, 9.9% carbohydrate, 15.5% protein
- Low-fat plant-based diet (also called vegan diet)
75.5% carbohydrates, 10.5% fats, 14% proteins
Both diets emphasized minimally processed foods.
And, as the researchers note in their article, these diets were more like the model diets often recommended by health experts.
An important note: This was not a weight loss study.
Instead, the researchers randomly placed 20 overweight participants (11 men and 9 women) on one diet for two weeks and then on another diet for two weeks.
On each diet, participants were given three meals plus snacks per day, carefully prepared to provide twice as many calories as each person needed. The dieters were then asked to eat as much or as little as they wanted.
What the study showed
People consumed 544 fewer calories per day with a low-fat plant-based diet than with a low-carb animal-based diet. (This data only covers the second week of each diet, to give participants time to adjust. For both weeks, the difference was even greater: 689 fewer calories per day).
Energy consumption was 166 calories per day higher on a diet low in animal carbohydrates than on a diet low in vegetable fats.
Glucose and insulin levels were significantly lower on a diet low in carbohydrates and animal products.
Participants rated both diets similarly in terms of enjoyment and familiarity. Therefore, one was not considered more acceptable than the other.
They also found no differences in satisfaction, sense of satiety or ability to eat, even though they consumed significantly fewer calories with the low-fat, plant-based diet.
Both groups lost weight without intentionally limiting food intake: 3.9 pounds during the low-carbohydrate, animal-based diet; 2.4 pounds during the low-fat, plant-based diet.
A low-fat plant-based diet alone (1.3 pounds) resulted in a significant reduction in body fat. A low-carbohydrate, animal-based diet resulted in a significant decrease (by 3.5 pounds) in lean mass, most likely due to water and glycogen, but this measure also includes muscle, bone, and organs.
What does this mean?
This shows that a diet low in carbohydrates and animals can provide metabolic benefits, but that a low-fat, plant-based diet provides other benefits. Indeed, people ate significantly fewer calories (but not necessarily less food), while feeling just as satisfied.
But instead of looking at the differences, look at the similarities:
The participants literally ate as much as they wanted and did not gain weight with any of the diets.
Of course, these two metabolic studies were very small and of short duration. While this is a limitation, there is a good reason for it: Imagine how difficult and expensive it is to get people to voluntarily live in a substance abuse facility for two months, let alone six months or a year. (Given the 2020 pandemic, you probably don’t need to imagine that).
However, these studies provide you with qualitative data obtained in a strictly controlled environment that you can verify yourself.
Because nobody has the right answer. We simply have a body of evidence that each of us must evaluate for ourselves.
Which brings us to the most important question of all.
What is most important for fat loss?
Whether you avoid carbs or eat a lot of them, one thing is certain: You can’t separate the calories from the food source.
Soda contains sugar. So is an apple. Both products contain mainly carbohydrates.
But you can’t eat this apple without also ingesting fiber, which slows down the absorption of sugar in the blood. It is also a solid food and rich in other healthy nutrients.
An apple isn’t a high-calorie or rewarding food either, so it won’t encourage your brain to over-consume like soda does. (For more information, read Manufactured Deliciousness: Why You Can’t Stop Overeating).
All these factors influence the feeling of satiety and food intake.
Message: A large serving of McDonald’s cola contains 80 grams of sugar and 290 calories. It’s relatively easy to eat in one sitting… with a cheeseburger and fries.
But you would have to eat four small apples (or 2.5 large apples) to get the same amount of sugar and calories from that soda. Do you know someone who is used to doing this in one session? Or does he want them regularly, even though he probably really likes apples?
(And if so, can we agree that they are the exception?)
Same amount of calories. Same amount of sugar. But a very different experience in terms of nutrition.
How might this affect your overall diet?
Dr. Hall conducted a study to get to the bottom of this problem.51
He brought 20 adults to an NIH metabolic center and randomly divided them into a diet of ultra-processed foods or a diet of minimally processed foods. They were allowed to consume as much or as little as they wanted. After two weeks they switched to an alternative diet for two weeks.
Results: As you can see in the graph below, participants in the superprocessor diet consumed 508 more calories per day and gained weight. They lost weight with a minimally processed diet.
Results of Dr. Hall’s study on ultra-processed versus minimally processed diets.
This may not be shocking, but it shows that the quality of the food we eat can have a greater impact on our weight than restricting carbs or fat. He also points out that quality food can promote weight loss without worrying about calories or hormones.
In his article, Dr. Hall describes ultra-processed foods as those that are generally high in calories, salt, sugar, and fat, and are designed to have unnatural appetite stimulating properties.
It’s no wonder people often call this food addictive. (Think of the slogan You can’t eat a single Lay’s potato chip).
Interestingly, a recent University of Michigan study examined the addictive properties of common foods.52
Take a look at the diagram below. These are the 10 foods that people most often label as problematic, according to the Yale Food Addiction Scale.
The glycemic load (GL) indicates the effect of a food on blood sugar levels based on the amount and type of carbohydrates. GL 20 and above are considered high glycemic load products. A GL value of 10 or less refers to products with a low glycemic load.
All but one of the foods are ultra-processed and most contain a combination of salt, sugar and fat.
What about products like lemonade that do not contain these three ingredients? They usually contain narcotic ingredients – such as caffeine and/or theobromine – to increase attractiveness.
Think about it: What products cause problems for you (or your customers)? And what do they have in common?
Which foods are also safe? That is, foods that you like, but can no longer eat without overeating.
How about an apple? Or salmon, cucumbers or beans? All of these types of minimally processed foods scored low on the scale.
(To check with yourself or a client, download our Yale Food Addiction Scale).
And if you discount the percentage of carbs, a simple preference for whole foods comes pretty close to what Dr. Ludwig, a low-carb advocate, recommends. According to his recent work14 :
|Dietary advice based on the carbohydrate insulin model|
|Reduce refined grains, potatoes and added sugars – carbohydrates with a high glycemic load and low overall nutritional quality.|
|Focus on low-glycemic carbohydrates, including non-starchy vegetables, legumes and non-tropical whole fruits.|
|When consuming grain products, choose whole grain products or traditionally processed alternatives (whole grain barley, quinoa, traditionally fermented coarse flour sourdough).|
|Increase the amount of nuts, seeds, avocados, olive oil and other healthy, high-fat foods.|
|Ensure an adequate, but not excessive, protein intake, including from plant sources.|
The emphasis on whole, minimally processed foods also seems to lead to better health. For example, in a recent Harvard University study, researchers examined the effects of healthy and unhealthy diets on all-cause mortality.53
Their conclusions: Consumption of minimally processed foods was, not surprisingly, associated with longer life expectancy.
So in the end…
It doesn’t matter what you think about insulin, carbohydrates or fat.
It may sound extreme, but what you believe doesn’t change what it takes to lose fat and keep it off (or to help a client do so):
- Use less energy than you spend
- Develop eating, exercise and stress management habits that are sustainable in the long term
If a low-carb diet helps you do that, all the better.
If a low-calorie diet helps you do that, all the better.
If a diet with a relatively equal ratio of carbs, fats and protein works better for you, that’s fine too.
Paleo, vegan, Mediterranean, keto, whatever you like: They are all viable and can be effective depending on your personal preferences, lifestyle and needs.
What to do now…
Look at the big picture.
Obesity and weight gain are multifactorial.
The amount of body fat absolutely depends on the food you eat, your activity level and, yes, your hormones.
But people are not robots.
You need to look beyond physiology and realize that there are many other factors that affect the amount of fat in the body, including:
- Social: The stigma of obesity and peer pressure to eat a certain way.
- Economic: the cost of nutrition and physical activity, and the pressure at work (leaving too little time for healthy eating and physical activity).
- Media: the influence of food advertising, body image in the media, and the availability of passive entertainment (think: do you have a Netflix subscription).
- Infrastructure : The ability to walk around the living environment, access to open spaces, and whether you do sedentary or physically active work.
- Medical: Any medications you take, diseases you have, or complications from surgeries you have had.
- Development: the importance of diet and exercise in your family when you were a child, and the attitudes you grew up with.
It is comforting to think that there is an easy answer, but that is not realistic.
Fat loss will likely take a series of small steps to achieve the desired results. Our advice: Focus on the big stones before worrying about specific food styles, timing of nutrients and supplements.
The big rocks are part of it:
- Choose mostly minimally processed, nutritious foods.
- Eat plenty of lean proteins and vegetables.
- get enough sleep
- Stress Management
- regular trips
- Reducing excessive tobacco/alcohol use
Large stones are suitable for almost any diet.
These basic nutrition principles apply to any dietary approach.
By basing the initial diet and lifestyle changes on these basic principles, you can ensure that the changes you (or your client) make will bear the most fruit.
Be open to testing your hypothesis.
Whether you already follow a diet or eating style to lose fat, or have a specific diet in mind, know that what works best for you may not be what you expect.
Whatever stage of the process you are in, put on your science hat and collect your data.
How will this diet work for me?
Here are some signs that it might not be right for you:
- Sustainability challenges
- It often gets out of hand.
- You feel tired, hungry and/or irritable most of the time.
- I don’t see any results.
- avoiding social obligations because it is too difficult to avoid temptations
If some of these points overlap, be prepared to take a different approach that may produce better results. (Download our Food Satisfaction Assessment for a complete questionnaire that can help you).
Remember there is no better diet.
There’s only what’s good for you. And that can change over time.
A universal miracle diet would make it easier to eat well. Unfortunately, there is no such thing.
The most important thing in fat loss – and in any other quest for health – is finding a diet that is sensible, sustainable and, yes, enjoyable.
And, of course, it’s a model everyone can agree on.
Click here to see the sources of information referenced in this article.
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If you are a trainer or want to become one….
Learning how to educate clients, patients, friends or family members about healthy eating and lifestyle changes that fit their bodies, preferences and circumstances is both an art and a science.
If you want to learn more about both, consider Level 1 certification.
Frequently Asked Questions
Is it possible to lose weight while on insulin?
It’s possible to lose weight while on insulin; however, doctors will caution that it can be a more difficult chore than if you are not on diabetes treatment. With insulin, you’ll need to adjust your goal for weight change. The greater the change, the more time that will likely need to be invested. Additionally, doctors often print BMI charts for safe weight gain predictions when beginning treatment. As a rough guide, doctors are often cautious to not start on any insulin control until patients are at 18-20 BMI.
Does high insulin levels prevent weight loss?
No, individual responses to dietary changes are based on genetic factors, personal preferences, hunger levels and the amount of energy stored in a given person’s body. Q: What does a person’s insulin level do after eating A: A person’s insulin levels increase after a carbohydrate-rich meal. Insulin then signals cells to use the glucose from the meal to produce excess energy in order to cope with the excess sugar. After the meal, insulin levels typically decrease. Q: How is insulin released on a diet A: Diet-induced (sometimes referred to as suppressed) or fasting insulin concentrations begin at the time of the meal or when carbohydrate/sucrose meals starts and peaks at ~60-90 minutes after the meal. Q: What is 1 sign of an insulin response A: A healthy person typically experience an insulin response after eating, and small occasional responses throughout the day. Q: What is the insulin hormone A: The term “insulin hormone” is used to describe all of the hormones produced by the beta cells of the pancreas. Q: What is the duration of a person’s insulin re A: A person’s insulin response tends to last for 70-210 minutes after a meal, coinciding with the peak of glucose release.
Which insulin makes you lose weight?
There are several different types of insulin. Some make you take in sugar from food and others make you release sugar from cells in your body. When you lose weight, your cells are under a lot of stress. When they are stressed, the cells release insulin. This is the insulin that gets out sugar. When the insulin does its job, it makes your cells enter a resting state and eat up their energy. So, when the cells eat up their energy, they start to shrink. This continues to shrink the cells and the body gets smaller. Like what some people say, diabetes makes people need to be always eating for their cells. Which diet should they be on? The person needs to have healthy reactions to the hunger signals coming from their brain. Nutritionists would recommend not carb-loading before big sporting events, which is what happens when you eat lots of carbohydrates for energy. This can lead to someone not feeling satiated for a long time and eating the calories they need all day. A good solution is to eat a lot of protein like if you are trying to build muscle, which helps to create glycogen and makes your cells use glucose instead of the poisonous energy during an intensity exercise session.
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