Lose weight: the pursuit of the perfect diet to feel good, prevent overweight, obesity and diabetes
In recent decades, the incidence of overweight, obesity and type 2 diabetes has increased avalanche in Sweden and the rest of the world. Overweight is the strongest risk factor for type 2 diabetes. In addition, excess weight causes liver disease, coronary heart disease (vein fat in the heart), stroke, heart failure, hypertension (hypertension), sleep apnea (respiratory arrest in sleep), joint problems (osteoarthritis) and increased risk of cancer.
The increased incidence of overweight, obesity and diabetes is today the biggest health problem in the world, according to WHO and a number of other organizations. This is extremely tragic because the absolute majority of overweight, obesity and type 2 diabetes can be addressed through diet and lifestyle changes that are quite simple to follow (but obviously we fail). Today, many — especially minor scientific blogs and websites — blame this epidemic of obesity on the food we eat. This, of course, is not correct, although the food is important for our weight and, accordingly, the risk of becoming overweight, fatty and developing type 2 diabetes. There are more causes, in addition to diet, and these were discussed in the chapter on Social Change that led to overweight, obesity and type 2 diabetes. In that chapter, however, we discussed societal changes and diet was not given particular focus. This chapter is only about food (diet).
Obviously, the food we eat is incredibly important. Scientists, caregivers and even laymen have realized this in the last two decades. The hunt for the perfect diet has never been as intense as it is at the time of writing. New methods, not infrequently promising dramatic and sustainable weight loss, appear all the time and it is difficult to judge what is correct and profitable to try to implement.
Half the population is trying to lose weight
You who are trying to lose weight are not the only one in your struggle. It is estimated that 45% of all women and 30% of men try to go down at any given time. Unfortunately, many people invest time and money in methods that are inefficient, expensive and/or harmful. In addition, the confusion is great about which food (diet) is best for those who want to lose weight. A fast and sustainable weight loss is optimal, of course, but the question is which diet gives you the best chance of getting there. This chapter consists of several parts. It is a long chapter and the aim is to give you a complete picture of what the collective science says and finally advice and instructions for you to succeed with your weight loss. We will review general aspects of overweight, obesity, diabetes, the purpose of losing weight, why it is difficult to lose weight, what effects weight loss has on the body, why it is difficult to maintain a weight loss and which diet is best for losing weight. With regard to diet, we will discuss LCHF (low carb high fat), other variants of low-carbohydrate diet (LCHF is a type of low-carbohydrate diet), high-protein diet, low-fat diet, Mediterranean diet, Paleo, low glycemic index diet and Atkins diet.
It can already be mentioned that diets that are poor in carbohydrates (also called low-carbohydrate, low-carb, low-carbohydrate) have become very popular in recent years and, moreover, there is scientific support that it works to lose weight, as well as to improve its risk factors for cardiovascular diseases. vascular disease.
Who is this discussion aimed at? Anyone who wants to lose weight.
Basically everyone will benefit from reading this discussion because it will discuss the food we eat, as well as how the food affects us. However, those suffering from overweight, obesity or type 2 diabetes have the greatest benefit. It should be noted that there is a fluid transition between normal weight (normal weight) and type 2 diabetes. You do not go from normal weight to type 2 diabetes in an abrupt stage, but this development is slow over time and as you approach type 2 diabetes, the risk of complications and diseases increases. In fact, the risk of type 2 diabetes is already rising at BMI above 25 (which more than half of all Swedish people have today). There is every reason to strive for as low a weight as possible. There is no science to suggest that low weight is dangerous (unless the low weight is due to smoking or illness). The only exception to this rule is osteoporosis (osteoporosis), which is aggravated by low body weight (even if you are healthy otherwise). So in other words, strive for as low weight as you can reach.
It should also be mentioned that this is important for those who have a blood lipid disorder (high lipids) and high blood pressure (hypertension). Obesity, overweight and diabetes lead to higher blood pressure and higher blood lipids (in addition to high blood sugar). Weight loss results in improved (lower) blood pressure, better blood lipids (more good cholesterol and less bad cholesterol) and lower blood sugar. Fortunately, it does not take much weight loss to notice positive effects. Weight loss has a wide range of health-giving effects.
Other relevant reading about diabetes, overweight and obesity
- Here you can read about type 2 diabetes: causes, symptoms, complications and treatment
- Here you can read details of drug treatment for type 2 diabetes
- Here you can read about the biology of overweight, obesity and diabetes
- Here you can read about obesity surgery (gastric bypass, obesity surgery).
How do I know if I am overweight or fat?
You can use BMI or waist circumference to clarify this. BMI and waist circumference are approximately as good measurements. The higher the BMI or the larger the waist circumference, the higher the risk of type 2 diabetes and other complications of obesity. If you already have diabetes, the higher the BMI you have increases the risk of complications. You can calculate your BMI below.
How to calculate BMI
BMI is calculated as your weight (kg) divided by the square of your height.
BMI 25 or higher means overweight. BMI 30 or higher means obesity. BMI 40 or higher means severe obesity.
How to calculate waist circumference
The waist circumference is measured by measuring the largest circumference around the stomach. You shall do this without clothing and standing (straight in the back). Use a tape measure that is placed on top of the hip bone (on the side of the stomach). Wrap the tape measure around the waist (parallel to the floor). Measure after exhalation.
The normal waist circumference is a maximum of 102 cm for men and a maximum of 88 cm for women. Larger waist circumference is associated with a higher risk of type 2 diabetes, cardiovascular disease, hypertension. Note that if you are from Africa or the Middle East, the waist circumference should be a maximum of 94 cm in men and 80 cm in women. If you are from Asia, China, Japan, or South America, the waist circumference should be a maximum of 90 cm for men and 80 cm for women. These ethnic differences are due to the fact that the risk of diabetes rises already at lower waist circumference in certain populations.
The higher the BMI, the worse the health. The vast majority of people who have a high BMI also have an impact on their health. Either so they can notice it themselves, or it can be seen on blood samples. The strongest is the connection between abdominal obesity and ill health. Abdominal obesity is, therefore, the obesity that exists around the organs of the abdomen (liver, intestines, pancreas, kidneys). However, there are people who are obese (BMI 30) who have no impact on neither blood tests nor subjective health. However, this is rarer and if you measure carefully, you usually find one or more deviations. BMI is, therefore, a great measure. However, to get a complete picture of your health, you need to consider several other risk factors (blood sugar, cholesterol, blood pressure, lifestyle, etc.).
Read more about type 2 diabetes here.
What is the problem with all the science? Nobody knows how to lose weight in the best way.
Scientific evidence is a difficult subject. It is, therefore, a question of what kind of studies we should rely on and how the results of studies are to be applied in reality. If you want to express an opinion on cause and effect, i.e. how something (e.g. a particular type of food) affects something else (e.g. body weight), then the most qualitative study is the randomized controlled clinical trial (hereinafter we call it only “clinical trial”). A clinical trial calls a number of study participants and then assign different treatments (or diets) randomly to the participants. It is believed that this gives maximum scientific credibility because the participants will be equal in all respects except for the treatment they received. Details about this are not important; all you need to understand is that if a study is a clinical trial, we have the greatest confidence in the results of the study. The second type of study is called an observational study, and in such a study we consider the participants of the study, without subjecting them to any experiment. This type of study is less reliable. Again, why the clinical study is the most qualitative examination, and why the observation study is less qualitative, does not belong to this discussion. You only need to note that a clinical trial is the best method for finding out which food is best for losing weight.
Clinical trials on diet and weight loss
There are plenty of clinical trials trying different diets to lose weight. There are often several studies that investigate the same thing (for example, there are dozens of large studies that compare LCHF to low-fat diets). Then the results of all studies investigating the same thing are merged and the combined result is used to express an opinion on the effectiveness of a type of diet. Not infrequently you see blogs and other publications that refer to such studies and write something like: “with this diet, you lose 5 kg in weight”. This is fundamentally incorrect. A clinical study, as well as those presented here below, is far from reality. In a clinical trial, the participants have access to completely different experiences than the ordinary ones in reality. In a study, participants often have access to doctors, nurses, dieticians, nutritionists, consultants, free food, gym cards and more. In addition, people are constantly monitored and they, therefore, have excellent conditions for losing weight. Last but not least, the people involved in a study are more motivated than the ordinary man; after all, they have agreed to participate in the study, which requires time, energy and resources. You need to keep this in mind when comparing your results with what you achieve in a clinical trial. Here below we will present many clinical studies.
People skip clinical studies, and many stop eating useful food and return to old habits
Despite rigorous controls in a clinical study, people usually drop out to a high degree (this is especially excellent for studies on weight loss and diet). This definitely affects the quality of the study. There are plenty of studies where more than half of the participants drop out during the course of the study.
In one study, there is rarely a tremendous variation in the weight loss achieved by participants. Some people actually gain weight during the study while others lose 30 kg. In principle, this enormous variation depends solely on individual adherence: we humans tend to stop listening after a while and return to our old habits. In other words, you can lose more weight than expected, provided that you are disciplined and motivated. If discipline and motivation are lost, well, then the whole effort can be in vain. Make sure that the motivation is on top!
Very many who are trying to lose weight have unreasonable ambitions and are disappointed when the result is present. Then one should know that even a small weight loss (5%) is highly beneficial to health and has a beneficial effect on blood lipids and blood sugar. The greater the weight loss, the better. A person with diabetes that goes down 15—20 kg can be cured (i. e. it does not have lower diabetes). Not everyone can achieve this, but everyone who can try should do it. 16
What is the goal of losing weight?
The importance of losing weight for those who have type 2 diabetes
Type 2 diabetes is today considered a chronic disease. By chronic, it means that they can not cure diabetes (i.e. get rid of the disease). This is not necessarily correct. One can get rid of diabetes (ie, one can be cured). Unfortunately, caregivers often fail to tell patients this, which is why lulled into the belief that the disease is guaranteed chronic. We must assume that there is a way to cure and if you do not get there, we must strive to get as close as possible. To succeed, one must lose weight. Studies suggest that weight loss of 15 to 20 kg often leads to the cure of type 2 diabetes! 17 Of course, this does not apply to everyone and only a few achieve this at the present time. With obesity surgery (gastric bypass), more than half of all people with type 2 diabetes are cured.
If you do not have type 2 diabetes
Overweight and obesity cause not only diabetes, but also fatty liver, liver failure, coronary heart disease (cardiovascular disease), sleep apnea, reflux, hypertension and increase the risk of several types of cancer. Losing weight means reducing these risks.
Why is LCHF (low carb high fat) so popular?
You who are trying or have tried to lose weight may have encountered LCHF (low carb high fat). LCHF is very popular, especially in Sweden. With this method, you actually lose weight by eating more fat and less carbohydrates (the explanation for this will be discussed in detail below). The big “problem” with LCHF is that scientists, food administration and society at large have always believed that fat in food affects blood fats. Because it has always been believed (since the 1960s) that fatty foods produce high blood lipids and we know that high blood lipids increase the risk of heart attack and coronary heart disease. Thus, the theory that fatty foods affect blood fats and thereby increase the risk of a heart attack is incorrect (discussed in detail here below). LCHF has gained more robust scientific evidence in recent years (especially during 2010-2017 when several major studies were published). Thus, the view of LCHF has been revised today and several major studies show that LCHF (or low-carbohydrate diet in general) leads to severe weight loss, which is also sustainable in the long term.
The advantage of LCHF is that you reduce the number of carbohydrates in the food and it seems that this leads to losing weight and also makes risk factors for cardiovascular disease (blood sugar, blood lipids, blood pressure etc) better! Therefore, LCHF (and various variants of this) are improperly popular today. The main advantages of LCHF appear to be:
- Weight loss comes quickly, compared to other diets.
- One does not need to count calories.
- There are many foods and dishes that are tasty and have high-fat content.
To succeed in a diet change, food must be tasty and enjoyable, otherwise, the change in diet will not be sustainable.
The following photo shows how to lose weight by LCHF, Mediterranean diet, as well as a low-fat diet. In this study, all three groups tried to lose weight with different types of diet.
The key to losing weight: understand why we are gaining weight
Obesity is the result of energy surpluses, i.e. you gain weight if you consume less energy than what the food contains. There are two factors that determine whether you get an energy surplus: (1) environment (i.e. our lifestyle) and (2) inheritance (i.e. the genes we inherited from our parents). The eternal question is which of these is the most important and the answer is an unequivocal lifestyle! Today, it has become very common to question the theory of energy surplus: many want to put the whole blame on carbohydrates, but this is a delusion that requires clarification. Carbohydrates are extremely important and reducing the carbohydrate content of the diet unequivocally leads to weight loss, but it is still the case that the balance between the number of calories we get through the food and the number of calories we burn still determines whether we are gaining or losing weight. If the energy balance is positive, i.e. we eat more calories than we consume, then we gain weight. If the energy balance is negative, i.e. if we eat fewer calories than we consume, then we lose weight. Excess energy is stored namely as fat in the body! The reason for distrust this theory is because studies that investigate if you lose weight by reducing calorie intake often show that you do not lose weight. This is because the body manages to “adapt” to the fact that the diet contains fewer calories by reducing metabolism; this is true to some extent, because the body can reduce metabolism and hence energy consumption if you eat less. However, in the long term, you lose weight due to lack of calories and the reason why you do not always see this in clinical trials is simple: participants fail to limit their calorie intake, at least not in the long term. If your goal is to lose weight by “counting calories” (reducing the number of calories you eat), then you should know that this is very difficult in the long run and probably not a sustainable strategy for the vast majority.
Well, back to why you gain weight. Over the last century, people have gone from living a physically demanding life to spending half the day on the couch and the rest of the day in the car, on the bus or office chair. Modernization and technological development have meant that we move less and consume less energy both at work and at leisure. It has also meant that food production has become enormously effective: it is now possible to produce huge quantities of food in a short time and, moreover, it contains many calories per gram of food. In addition, larger portions of food are served and the bottom line is that we get larger amounts of energy (calories) and spend fewer and fewer. It should also be mentioned that the Food Agency, as well as its counterpart in the US and European countries, has been recommending a low-fat diet with a relatively high carbohydrate content. This has probably also driven the obesity epidemic because carbohydrates make you gain more weight, compared to fat. 18
Although our lifestyle is the most important cause of diabetes and obesity, genes have some meaning. Approximately 300 variants of different genes (gene variants) have been identified that affect weight. The most important gene is the so-called FTO gene. Some variants of the FTO gene lead to a thickening of 1 to 3 kg compared to people who have other variants of the gene. It is important to point out that all 300 genes together affect only about 5% of your body weight, so the rest is lifestyle! But you can actually inherit your way of life; you usually say that the apple does not fall far from the tree, and it often applies to how we behave, what choices we make in life and how life is shaped. There are plenty of apples that have distanced themselves from the tree, but this must be borne in mind. Studies show that 40 to 70% of obesity is inherited if you consider that both genes and lifestyle can be inherited. Of course, there is an interaction between genes and the environment. A person who has heredity for overweight, obesity and/or diabetes must be more careful (in terms of diet, lifestyle, etc.) than people without those conditions.
Nutrients that affect our weight: fat, carbohydrates, protein?
Before discussing different diets (types of diet) for weight loss, we’ll say a few words about macronutrients. Macronutrients are the main nutrients in food and they are as follows:
These three substances contain energy and building blocks that the body needs to function. Carbohydrates, protein and fat are therefore used both as fuel and building blocks in the body.
For decades, it has been believed that the important thing is the total amount of energy obtained from these three nutrients. That is, therefore, the debate on energy balance. The incoming energy is what we eat and outgoing energy is what we spend (walking, exercising, or just sitting still, burning constantly). It has always been believed that the energy balance is the most important and that the actual distribution between these three nutrients is of minor importance. However, this has begun to be questioned today. More and more people believe that carbohydrates have a greater impact than the calories themselves contained in carbohydrates. It’s easy to understand why: protein and carbohydrate are about as energy-rich, but you can lose weight by eating more proteins and fewer carbohydrates even if the total amount of energy is kept constant. In other words, carbohydrates seem to have a different impact on our metabolism and the result is that it is more difficult to lose weight with a diet rich in carbohydrates.
In the popular diets that exist today, there are clear differences in the distribution between these three nutrients. LCHF means reducing the intake of carbohydrates and increasing the intake of fat. Low-fat diet means reducing the intake of fat and increasing the intake of carbohydrates (preferably carbohydrates with a low glycemic index, see below).
Carbohydrates in food: weight gain regardless of the calories?
Carbohydrates occur in many different forms. However, all carbohydrates are made up of smaller building blocks, of which there are three pieces: glucose (glucose), fructose (fruit sugar) and galactose. In the food, there are different types of carbohydrates, but they consist of these three building blocks (also called “monosaccharides”). So the food we eat contains a leaf of various carbohydrates. In potatoes, there is plenty of starch, which consists of many interconnected units of glucose. Table sugar contains sucrose consisting of interconnected fructose and glucose. In milk, there is milk sugar consisting of glucose and galactose. No matter what the carbohydrates look like, our enzymes in the intestines will try to break down the carbohydrates into their smallest constituents, namely glucose, fructose, and galactose, which are then absorbed by the intestines and thus end up in the body. Fructose and galactose are converted to glucose (glucose) in the liver. This means that all the carbohydrates you eat are converted to glucose (glucose) in the end! There is one exception, namely fibers. Fibers are carbohydrates that usually consist of interconnected glucose units, but the copper is of a particular kind that human enzymes cannot break and therefore we cannot take up fiber as energy. Fibers, therefore, contain no calories for us humans. The fiber content of the food thus passes through our small intestine (where nutrients are absorbed) and continues to the colon where there are bacteria that can break down and use the energy content of the fibers.
The important thing to understand is that all carbohydrates, except fiber, turn into glucose in the body. The body only uses glucose (glucose) as an energy source (thus galactose and fructose must be converted to glucose first). In addition, the body would rather use glucose than fat and protein. This is because our metabolism (metabolism) is set so that glucose is always preferred, although fat is more energy-rich than glucose, and proteins are just as energy-rich. If we eat more carbohydrates than we need, then the excess will be stored in the liver (like “glycogen”) as well as in the fat tissue as normal fat!
Only if there is a lack of glucose, the body will use fat as a fuel (which means that fat is broken down) and, at the very last, protein is used. However, the energy contained in fat is adequate and can supply the body’s energy needs perfectly and also for a long time. In fat there are both fatty acids (which contain energy) as well as glycerol that can be converted to glucose in the liver! That’s why blood sugar does not drop very much during fasting, we can, of course, get glucose (glucose) out via the glycerol of fat!
Today (June 2017), the Finnish Food Administration recommends that 45 -60% of food energy be derived from carbohydrates. For a normal-weight person who eats about 2000 kilocalories (kcal) per day, it corresponds to between 250 g and 300 g of carbohydrates. However, the body does not need this amount of carbohydrates to cope. Rather, 130 g of carbohydrates per day is what the body wants and this is because the brain consumes about 130 g of glucose daily. But the truth is that the brain is able to function normally even on the energy contained in fat, and it is rather the case that the body can manage 60 to 65 g of carbohydrates in food per day. 19. This is due to the fact that the body (more specifically the liver) is able to make its own glucose via fat and, in addition, all cells in the body can make a living from the energy contained in fat.
Low-carbohydrate diet (LCHF): lack of carbohydrates causes the breakdown of fats
Low-carbohydrate diet (e.g. LCHF) aims to produce a lack of carbohydrates which leads to the start of fat degradation. Food that is very strict LCHF, i.e. has very low carbohydrate content, is called ketogenic diet (ketogenic diet) because it aims to end up in “ketosis”, which is a condition where fat breaks down and uses the energy contained in fat as a fuel instead of glucose. Fat contains several forms of energy, as follows:
- Fat contains glycerol, which is converted to glucose (glucose) by the liver. This glucose can be used by all body organs.
- Fat contains fatty acids that can act as fuel in most cells, but not the brain.
- Fat contains fatty acids that are converted into ketone bodies (also called ketones) in the liver.
- Ketone bodies can be used as energy by various organs, especially the brain.
Diet containing limited carbohydrates will cause the body to want to extract the energy contained in fat and thus break fat down!
LCHF and low-carbohydrate diet have additional effects that are believed to be important for losing weight on this type of diet. This is discussed in detail later.
Challenges and effects of losing weight
For those who wish to lose weight by reducing their intake of calories, there are very good tools (calculation models) to predict how much you can lose weight, as well as when you can reach your weight goal. See this tool (English) from NIH. That tool is proven and has high precision, but the truth is that it is extremely difficult to achieve a sustainable weight loss by “counting carbohydrates” (i.e. limiting their calorie intake). We are not aware of any study that showed that you can achieve long-term weight loss by counting calories.
The vast majority of studies also show that those who are trying to lose weight most often succeed, at least temporarily. Initially, it goes fast and after that you usually gain weight again after some time. This applies to all methods of losing weight, including medicines, dietary treatment, surgical treatment (obesity surgery/gastric bypass). There are several reasons why gaining weight after some time. Those discussed most often are the following:
- You stop following the advice you’ve been given. If the weight loss has been achieved through changes in the diet, this means returning to your old diet. This can occur gradually or abruptly. As a result, you also gain weight again. This is undeniably an important factor. In the most ambitious and resource-intensive dietary studies, up to 50% of study participants have dropped out after some time because they are no longer interested. The same applies to lifestyle changes related to exercise. We humans simply find it difficult to establish new habits.
- The body’s metabolism and hormones change by losing weight. There is evidence that weight loss leads to the body (especially the fat tissue) trying to counteract weight loss by changing the hormonal balance in the body. This means that weight loss leads to a change in the hormonal balance so that hormones that increase appetite and hunger are released more than normal.
If you are trying to lose weight by limiting calories (“counting carbohydrates”), you must also be prepared for the fact that the body will try to counteract the situation through a series of mechanisms that suppress metabolism and increase appetite. Metabolism is slowed down by downregulating (reducing) the basal metabolism, i.e. the metabolism that the body always has for it to survive. The basal metabolism is very important for our total energy consumption because it is running around the clock; so if it is downregulated, then we simply consume much less energy and this complicates weight loss (while hormones will increase your hunger and appetite). 20.
How much do you need to lose weight to get healthy effect?
Already at 5% weight loss, the pancreas feels better, and the beta cells (those who make insulin) recover their function, and insulin sensitivity rises. With 5 to 10% weight loss, good effect on blood pressure, cholesterol, mental health and a number of other factors is also seen. With further weight loss, the fat tissue’s hormone signaling improves (i.e. it becomes more normal). 21 Blood sugar (as well as long-term blood sugar HbA1c) is very dependent on the degree of overweight. One of the most important factors for normalizing blood sugar is losing weight!
Therefore, weight loss does not have to be dramatic for it to be healthy. Although it is desirable to lose as many kilograms as needed to gain normal body weight, then a few kilograms of weight loss can also be very effective! Among overweight and people with obesity, it has been noted that weight loss of 5.6 kg reduces the risk of type 2 diabetes by 58%! This effect actually lasts up to 10 years after losing weight! 22
Weight loss of 16 to 32% is seen after surgical treatment (obesity surgery, gastric bypass). This very often leads to a cure if he has type 2 diabetes (blood sugar becomes normal and you do not need medicines). In addition, the risk of complications decreases and life expectancy increases! This is unequivocal. 23
Unfortunately, sleep apnea (stopping breathing in sleep) is rarely cured by weight becoming normal, which is of course a little strange.
How many manage to lose weight and maintain their new weight?
Approximately 20% of all overweight manage to maintain a weight loss of 10% weight loss over 12 months 24. The best tricks to maintain their new weight are to choose a simple diet, eat with variety, but not too much variety, have breakfast every day and exercise. Which diet you choose is, of course, fundamental to succeeding in dietary changes and achieving effective weight loss.
Strategies and diets for losing weight
The vast majority of methods of losing weight work to any degree. This means that the one who tries to lose weight most often succeeds. This fact is almost independent of which strategy one chooses (ie, choice of diet, degree of physical activity, etc.) to lose weight. Thus, there are studies that show that you can lose weight from everything from cognitive behavioral therapy (CBT) to various diets. The explanation for this is simple: when you pay attention to your excess weight and decide to do something about the problem, you do better. You get careful about what you eat, how much you eat, what you drink, how much you move, and so on. Science, therefore, shows that most diets lead to weight loss and after 6 months you can get rid of 8 -10% of their original weight. The big challenge lies in maintaining their new weight, and all science suggests that this is very difficult.
See the following two pictures. The first shows weight loss after surgical treatment for obesity with a so-called “gastric bypass”. As you can see, you’re losing weight at first, and after a while, you’re gaining weight again. This is extremely typical for a study that tries to get the participants to lose weight (mechanisms have been discussed above).
The next photo shows the same phenomena with different types of diet (low-fat diet, Mediterranean diet, low-carbohydrate diet) to lose weight.
Causes of gaining weight on low-calorie diet
One obvious reason is that you get worse at keeping your diet. You start eating unhealthy food again and then you gain weight. But the body also counteracts weight loss in several ways. For example, low-calorie diet leads to the body reducing its burning at rest; i.e. the fewer calories you eat, the less calories the body consumes at rest (burning at rest is important for our total burning because we are at rest most of the day). The brain becomes more and more food fixation if you reduce your food intake. This leads to increased hunger and psychological stress that can lead to compensatory high food intake. This has been discussed above, but it is, therefore, worth mentioning again because it is a challenge to counteract these mechanisms with discipline. 25
MacLean PS et al. The role for adipose tissue in weight regain after weight loss. Obes Rev 2015; 16: Suppl 1:45-54. Sumithran P et al. Long-Term persistence of hormonal adaptations to weight loss. N Engl J med 2011; 365:1597-604. Leibel RL et al. Biologic responses to weight loss and weight regain: report from the American Diabetes Association research symposium. Diabetes 2015; 64:2299 -309. And CN et al.: Treating obesity seriously: when recommendations for lifestyle change confront biological adaptations. Lancet Diabetes Endocrinol 2015; 3:232-4 [/footnote].
It is therefore extremely important that you be extra vigilant when you lose weight, otherwise, you get back up!
Those of you who are on the lookout for the perfect diet might wonder where that discussion went. In fact, what you have read above is at least as important for your success. One needs to have a basic understanding of how obesity, overweight, diabetes, weight loss and the body’s metabolism works. This improves your ability to lose weight and maintain your new weight.
Diet and diets for losing weight
This discussion is therefore about diet, because a good diet can be extremely effective in losing weight. In my work as a doctor, I rarely saw motivated patients lose 5 kg per month by changing their diet. Diet is therefore extremely effective for losing weight, but eating the right food is important and discipline must be on top. With the right approach and discipline, the diet can be all you need to lose weight, become more healthy and feel better.
Over the years, a wide range of different diets has been developed. These diets can be divided into the following categories:
1. Low-fat diet (low fat diet): less fat in food
Low-fat (also known as low-fat or low-fat) diet has been the food agency’s prescription for over 50 years. There are, of course, a number of varieties of low-fat diet, but common to all is that you should eat some fat. Overweight patients starting low-fat diet in clinical trials may lose 3-4 kg after approximately 3 years. There is also a wide range of studies that show that you do not lose weight by low-fat diets. Of course, there is a difference between different types of fats (especially animal fats and vegetable fats). The principle of low-fat diet is that the fat you eat should be predominantly vegetable fat.
2. Low-calorie diet (low-calorie diet, low-calorie diet): fewer calories in food
A low-calorie diet contains less calories than is expected to be needed (thus varies from individual to individual). This type of diet means reducing the number of calories you eat daily. Thus, all nutrients are reduced; fats, carbohydrates and proteins. Most low-calorie diets involve eating between 1000 kcal and 1450 kcal daily. Diets that involve eating meal substitutes (drinks or “bar”) are included in this type of diet. A meal substitute usually contains about 240 kcal, which is less than a Swedish standard meal.
3. Very low-calorie diet (very low calorie diet, heavily calorie-reduced diet): even less calories
Very low-calorie diet involves aiming at eating less than 1000 kcal per day. Ideally, you should eat relatively more proteins than fats and carbohydrates, because proteins are more satiating and this is needed when you eat so few calories.
Low-calorie diet vs. low-fat diet
If you want to lose weight, low-calorie diet is more effective than low-fat diets. Most studies show that you lose about 6-7 kg after 4 years on low-calorie diets. However, it should be mentioned that there are studies showing that very low-calorie diets are not necessarily better than low-fat diets in the long term. This is probably due to the fact that one does not manage to maintain the low-calorie diet over time!
Meal replacements: good or scam?
Meal replacements are likely to result in losing weight. However, there are no reliable clinical trials. An observational study showed that 8 kg was lost in 4 years with the help of meal replacement. 26
Low carbohydrate diet (low carb diet, low carbohydrate diet, LCHF): reduce carbohydrate
Low carbohydrate diet, low-carb diet or low-carbohydrate diet involves limiting the amount of carbohydrates in food. There are several variants of low-carbohydrate diet (low carb) and they differ mainly in the following respects:
- How much carbohydrates you get to eat.
- How much protein to eat.
Restriction of carbohydrates is what is considered to control weight loss. ZONE and CSIRO are low carb diet that involves making a small restriction on the amount of carbohydrates. On the other hand, the Atkins diet, South Beach and LCHF mean that carbohydrates are severely restricted. LCHF stands for low carb high fat and means that you reduce the amount of carbohydrates sharply and instead you eat a lot of fat. LCHF has been very popular in Sweden in recent years. The difference between LCHF and Atkins diet is that LCHF advocates high fat intake while Atkins diet advocates high protein intake. Here is a picture showing the differences in the content of fats, proteins and carbohydrates in different types of diets:
5. Diet with low glycemic index (GI) and low glycemic load (GL): slow carbohydrates
Low glycemic index means that carbohydrates should be slow. Carbohydrates are allowed, but they must be of special quality so that they do not lead to a rapid increase in blood sugar. This is discussed in detail later.
What is it proposing today? The Unified Diet!
The dietary recommendations recommended by Swedish, American and European food authorities over the last 5 decades can be summarised as follows:
- The food should contain few calories.
- The food should be low-fat (low barrel). Maximum 30% of the food should consist of fat.
- The food should contain as little saturated fat as possible (max 10% of the fat). Saturated fat is such that is solid oil at room temperature (e.g. butter). The preference should be given to unsaturated fats (liquid oils).
- Preferably complex carbohydrates, i.e. non-sugars carbohydrates. Such carbohydrates are found in whole grains, beans, vegetables, peas, etc.
- Approximately 15% of food should consist of protein.
These guidelines are prepared by the American Heart Association, the American Cancer Society, NIH and others. The diet is called “The Unified Diet”, which refers to the fact that it is a common diet recommended by cardiovascular specialists, cancer specialists and health authority. The aim is, of course, that the diet should minimize the risk of cardiovascular disease and cancer. The Swedish diet circle is very similar to this diet, which is due to the fact that scientists in America and Sweden have agreed on what is considered to be health-promoting diets.
The main goal of this diet is to limit the fat content of food. It has always been believed that the fat content of the food affects the amount of fat in the body (i.e. how much we weigh). This seems logical because fat is very energetic and fat in the food consists of triglycerides, which also fat in the body does. In the United States and the rest of the world, there has been a very aggressive campaign against fat in food, and it has actually managed to reduce the amount of fat that people eat. Unfortunately, this has not led to the narrowing of the population; on the contrary, the population has become thicker! If the amount of fat in food were so crucial, a reduction in the consumption of fat in the population should lead to a noticeable weight loss, which is not the case. There are plenty of qualitative studies that show that reduced fat content in food offers neither weight loss nor protection against cardiovascular disease (discussed later). 27
Reducing the amount of calories also seems logical because the body weight also depends on the energy balance, i.e. the balance between the number of calories we get in us compared to the number of calories we spend. In principle, every qualitative study done shows that low-calorie diet makes you lose weight, but usually, this is temporary and after some time you gain weight again. This is because it is incredibly difficult to keep a low-calorie diet because your body’s reaction is to increase your hunger and appetite.
As for saturated fat, the theory has stated that saturated fats (oils that are solid at room temperature) lead to higher cholesterol levels and thus increase the risk of cardiovascular disease. This is a truth with modification and, probably, saturated fats are not at all as dangerous as previously thought.
Several researchers actually believe that these dietary recommendations are the reason why we become thicker because of reduced fat content in our food has led to an increase in the proportion of carbohydrates in our food. 28
Carbohydrates have been shown to affect weight more than fat. Over the past 10 years, dietary advice with low carbohydrate content (e.g. LCHF) has gained much ground because it has been shown to provide faster weight loss, which has been easier to maintain, without increasing the risk of cardiovascular disease (heart attack, stroke, angina pectoris. 29
Low-carbohydrate diets (low carb, LCHF) have become improperly popular today. In Sweden, LCHF is the most popular variant and therefore advocates eating as little carbohydrates as possible and compensating by eating a lot of fat. There are many varieties of low carb diets but common to all of these is that the amount of carbohydrates is limited (30%). In other countries, the Atkins diet is very popular, although interest has dawned in recent years. Atkins diet involves limiting carbohydrates without limiting total caloric intake. It is believed that the explanation for the effectiveness of LCHF (or low carb in general) is as follows (details will be discussed later):
- Reduced intake of carbohydrates leads to the fact that the body does not release as much insulin. When the insulin level drops, the breakdown of fat in the adipose tissue increases. The fat is broken down into fatty acids and some of the fatty acids are converted to ketones in the liver. Fatty acids and ketones are not only energy-rich, they have a saturating effect on the brain (we become less hungry).
- Reduced intake of carbohydrates usually means eating more proteins, and proteins are satiating.
Mediterranean diet (diet similar to the one you eat around the Mediterranean) is proven better than the “usual dietary advice”. The traditional Mediterranean diet is characterized by a high intake of olive oil, fruits, nuts, vegetables and cereals; a moderate intake of fish and poultry; a low intake of dairy products, red meat, processed meat and sweets and wine in moderation. The Mediterranean diet is the only diet that has been shown to reduce mortality and cardiovascular disease! The Mediterranean diet also leads to weight loss, improved quality of life and well-being. 30
Continuation of how to lose weight
In the next chapters, we will discuss how to lose weight with the help of various diets and what to expect from these diets.
- Low-fat diet is discussed here
- Low glycemic index and low glycemic load are discussed here
- Low carbohydrate diet (low carb, LCHF) is discussed hereHigh-protein diet is discussed here
- Paleo (Paleolitic diet) is discussed here
- Calorie low diet, meal replacement is discussed here.
Our final recommendation of what you should eat to lose weight and prevent ill health can be found here.