The word metabolism is on everyone’s lips today, although each person interprets it in their own way. This article clears up the main doubts about him.
What is metabolism? It can be defined as the set of biochemical reactions that happen in the body, either to obtain energy and organic molecules (anabolism), or to destroy them (catabolism).
It is therefore an essential process for health, but its keys are still largely unknown. However, taking into account what is known can help us enjoy a healthy metabolism and treat its alterations when they exist. Obesity, diabetes and many other health problems are often attributed to poor metabolism function.
You can describe the general metabolic mechanisms that science knows, but in reality, there are as many metabolisms as there are people. It is possible that on the inside we are as different from each other as on the outside.
The effects produced by food and especially the ease or difficulty in staying in the weight margin that corresponds to us are important clues. The main difference between some metabolisms and others is the speed with which they transform nutrients into energy.
CAN METABOLIC SPEED BE CHANGED?
Metabolic speed is higher in people who gain weight with difficulty and slower in obese or overweight people.
These can stimulate your “thrifty” metabolism through the use of drugs, natural remedies or habits that complement a proper hypocaloric diet.
It is evident that the metabolic speed increases with exercise, because in addition to starting the muscles, it triggers biochemical reactions to obtain energy and eliminate waste.
WHY DO YOU REGAIN WEIGHT FASTER AFTER GOING HUNGRY?
Becausethe body judges it a priority to do so and devotes its best resources to it.
During withdrawal, the body saves energy but then, when it is obtained again, it transforms it more quickly than before into muscle and especially fat.
ARE THERE SEVERAL TYPES OF BODY FAT?
Yes: white and brown. The first is made up of cells with few mitochondria and the second – exclusive to mammals – has many.
Mitochondria are small cellular organs located in the endoplasmic reticulum whose function is to produce energy. The more mitochondria, the more glucose combustion capacity and the greater the ability to eliminate energy by radiation (increase in body temperature).
White fat, having fewer mitochondria, is a reserve fat, “saving” and with little capacity to transform its energy. All people have these two types of fat, but the proportions vary.
The brown is located especially in the armpits, in the interscapular area and in the neck. People with a lot of brown fat can eat a lot and exercise little without gaining weight. Those who have too much white fat have the opposite true.
The proportions of the two types of fat vary with age, since with the passage of time the brown is reduced in favor of the white. That is why as you get older it becomes more difficult to maintain the ideal weight.
Children and adolescents have a greater amount of brown fat, which together with their hormonal status (secretion of growth hormone, high thyroid function …) It makes them fatter with more difficulty.
ARE THERE DIFFERENT METABOLIC TYPES?
We have seen that there are differences between people in the proportions of white and brown fats.
There are also different models of fat distribution in the body. Some people tend to accumulate it in the abdomen and others in the hips, legs and buttocks. The former are more at risk of heart disease.
Another classification of metabolic types, which is not shared by conventional medicine, is based on the influence of diet and psychophysiological types. William Wolcott describes three basic types: carbohydrates, proteins and mixed. Each one works better with a series of foods and suffers when he eats those that do not suit him.
According to Wolcott, being of one type or another is a consequence of information inherited from parents, which also relates to the type of food available in their geographical environment. This would be the reason why populations that abandon their traditional diet and adopt those of other human groups tend to suffer a high incidence of metabolic disorders.
The challenge is to find out what the metabolic type itself is through the knowledge of the preferences and effects that food causes us.
It should be borne in mind that although the characteristics of metabolism are partly inherited, they are still subject to modifications throughout life.
TO WHAT EXTENT IS METABOLISM GENETIC?
On chromosome number 6, a gene related to the mechanism of satiety has been found. But that does not mean that the characteristics of metabolism and its functioning are governed entirely from the genes.
Swedish and English researchers have found a link between grandparents’ diets and the incidence of diseases such as obesity and diabetes in grandchildren.
Apparently, a person may have a metabolism that is not adapted to a situation of food abundance because their mother or grandmother went hungry at a critical time in their lives.
However, family influences must surely be accompanied by dietary errors so that diseases finally end up manifesting.
WHAT DETERMINES APPETITE?
The word metabolism comes from the Greek metabola and means “transformation”.
It alludes to the central process that converts glucose into energy, called the Krebs cycle. This cycle is carried out by all cells to produce the so-called acetyl-coenzyme A, which transmits the energy necessary for life.
On the other hand, numerous relationships between the different neurotransmitters circulating in the body, the mechanisms of appetite and the assimilation of food are also part of the metabolism.
For example, dopamine, a substance produced in the adrenal glands, seems to be the door that opens the appetite and that conditions the number and number of meals made per day.
Adrenaline and noradrenaline, stress hormones, stimulate energy consumption: they moderately raise body temperature and increase the body’s overall expenditure.
This involvement of neurotransmitters in temperature, hunger and food sometimes makes it difficult to distinguish between hunger, stress or depression and whether appetite is conditioned by emotional conflicts or not…
That is why it is important to make a good psychological and emotional evaluation of the factors that influence a person’s diet before proposing a treatment, whatever the type.
As we can see, the metabolism of each person constitutes a unique puzzle. But it is not finished or untouchable. It is possible to move pieces, make tests and adjustments until we find the fit that makes us feel better.
And metabolism varies over the years, even with mood and attitude. You have to keep this in mind and be willing to change when circumstances demand it.
ARE THERE MECHANISMS THAT STABILIZE WEIGHT?
Yes. There are three mechanisms for weight control.
- One is the regulation of appetite and the reduction of the amount of food consumed.
- Another is the reduction of anabolism, or absorption of nutrients present in food.
- The third is increased catabolism, burning a greater amount of energy to achieve the same activity. Reducing our body’s energy efficiency could help us stay at a good body weight.
A human being ingests about 900,000 kilocalories a year. An increase of only 5% in the energy of the food we consume can lead to an increase of 6 kg of adipose tissue per year.
However, this does not happen, since body weight has a clear tendency to remain stable for long periods of time, even in times when we do not exercise significant control over our dietary and lifestyle habits.
Diets to lose weight or gain weight are in principle ineffective when they have to cross this point, which is called “set point”. The metabolism refuses to abandon it and causes the complaints of those who are losing weight and suddenly verify that not only does not lose weight, but even gains it by eating very little.
Apparently, the function of the “set point” is not to lose reserves that the body considers necessary. It seems to be regulated by neurotransmitters, which has aroused interest in finding a substance that acts on that control of energy expenditure. But it is not an easy task, it may even be impossible.
There are specific areas of the brain that seem to regulate the “set point”, which is mediated by the neurovegetative or autonomic system, although the central impulses seem to derive from the lateral and ventromedial areas of the hypothalamus.
This is known because lesions of the hypothalamus are often followed by alterations of the body’s fat content.
From the studies carried out on the “set point”, it is deduced that obese people do not have any metabolic alteration. What happens to them is that their “set point” is located at an excessively high level.
WHAT ARE LEPTIN AND GHRELIN FOR?
They are two substances that seem to have a powerful appetite suppressing effect.
Ghrelin is a hormone produced by the stomach and modulates appetite in the short term. When the stomach is empty, ghrelin increases appetite, while when it fills up and exerts its secretory and absorbent function, it reduces it.
Leptins are secreted by adipose tissue to indicate the levels of their fat deposits. This regulates appetite in the medium and long-term depending on whether or not they reach the magnitude programmed for the organism.
Everything suggests that, if used as medicines, leptins should be effective in regulating appetite and in the treatment of obesity.
The test has already been carried out and it has been observed that its administration is only somewhat effective in thin people, but much less in obese people, who seem to have developed a resistance to the biological action of these organic substances.
ARE THERE PLANTS THAT INHIBIT HUNGER?
Gymnema is an Indian plant with the curious ability to inhibit sweet and bitter taste, while respecting acid, rough and spicy.
It has been used as a treatment for type 1 diabetes because it improves the effectiveness of insulin. In combination with other products, it is used in the control of glycemia and cholesterol (reduces the absorption of glucose and stimulates the modulating function of the pancreas on it).
The usual dose is 400 mg of the extract once or twice a day.
Stevia is a non-caloric sweetener, but also useful in the treatment of obesity, diabetes, hypertension and uric acid.
The leaf of this plant, which is therapeutically used in doses of 1 g daily, is a hundred times more sweetening than sugar.
But the most interesting thing is that it increases the synthesis of glycogen in the liver, which has a moderate diuretic action and stimulates the secretion of insulin, improving glucose control.
In case of taking medications for diabetes or hypertension, it will be taken into account that their consumption can increase the effectiveness of the drugs. On the other hand, the sale of this plant in our country is restricted by the Ministry of Health.
WHAT FOODS STIMULATE METABOLISM?
In addition to physical exercise, introducing changes in the diet is essential to accelerate metabolism. In general, it is advisable to avoid carbohydrates of rapid absorption and introduce some stimulants.
Green tea is the leaves of the tea plant, simply, dried and unfermented.
Studies indicate that epigallocatechin in green tea is a good complement in the treatment of obesity, as it can increase caloric metabolism and fat degradation.
The dose can vary between one and six cups a day, calculating that each one provides about 80 mg of caffeine and a comparable number of polyphenols with medicinal action. In many populations in Asia, it is consumed once or several times a day and no undesirable effects have been observed.
It also prevents atherosclerosis, cancer and skin erythema, and improves care.
Its hydroxycitric acid (up to 50% of its weight) modifies metabolic speed and increases energy expenditure.
It also seems that garcinia interferes with fatty acids by reducing their ability to accumulate in the body’s fatty tissue.
There is some scientific evidence that also indicates that the consumption of garcinia moderately reduces appetite.
Doses of 1 g are used, two to four times a day.
Fucus seaweed is used for its high iodine content (600 mcg per gram of plant), which stimulates the thyroid. Due to its high iodine content, it is not recommended in people suffering from hyperthyroidism.
It has been used as a treatment in case of hypothyroidism, but it is also one of the usual complements in plant formulas for the treatment of obesity.
Its discreet content of soluble fibers, especially mannans, means that it can reduce, even slightly, the threshold of satiety and reduce appetite.
The usual dose in these cases is 2 to 5 g daily in the form of capsules, extracts or herbal teas.
WHAT IS METABOLIC SYNDROME?
There is increasing talk of metabolic syndrome or “syndrome X”.
It is estimated that in Spain 20% of the adult population suffers from it.
The concept refers to the presence of at least three alterations that together represent a serious risk to cardiovascular health. This population group triples the risk of suffering from severe cardiovascular disease. This is the cause of death in 80% of those affected.
There are also other related factors:
- One of the frequent disorders is obesity with abdominal predominance. It is considered that this exists if the waist circumference is greater than 102 cm for men and 88 cm for women.
- Low levels of “good” HDL cholesterol (equal to or below 40 mg/dl for men and 50 mg/dl for women) and high triglyceride levels (150 mg/dl or more) indicate lipid alteration.
- Increased insulin resistance: in principle it is not necessary to suffer from diabetes but that there is a poor response to sugar ingestion. People with metabolic syndrome have morning blood sugar of 110 or higher.
- High blood pressure is another typical symptom of the syndrome: equal to or above 130/85 mm of mercury.
- Existence of prethrombotic lesions, often with alterations of coagulation factors.
- Pro-inflammatory state, sometimes observed with elevation in CRP (C-reactive protein) analyses.
It is known that the only valid and widely effective treatment is to reduce weight and increase exercise. It is difficult to assess the impact of moderate obesity on people with metabolic syndrome, since in fact most problems arise from associated diseases and not so much from obesity, which is a factor stimulating complications.
HOW DO I KNOW IF I HAVE OBESITY?
Since there are different metabolisms, it is logical that they are reflected in varied body figures. It is not sensible for us all to aspire to the same ideal figure. So, who is really obese?
The simplest method of calculating obesity is what has been called Body Mass Index (BMI). It is calculated by dividing the weight in kilos by the height in meters previously squared.
For example, in a person weighing 70 kg and 1.75 m tall it would be: 75 / (1.75) ² = 75 / 3.06 = 24.5.
- below 18.5, indicates abnormally low weight,
- between 18.5 and 25 is considered the ideal weight,
- between 25 and 30 indicates overweight,
- Between 30 and 35 is obesity
- and BMI greater than 35 indicate morbid, pathological obesity.
A BMI above 30 is considered to increase the risk of negative health implications.
However, BMI has problems: it does not distinguish whether weight is due to a lot of fat or a lot of muscle, nor does it take into account the body’s distribution of adipose tissue.
Consequently, a muscular athlete can get a figure of obese when he is not. In highly trained athletes, with a lot of muscle, this BMI can be abnormally high without implying obesity.
Other methods, such as the calculation of subcutaneous fat, the measurement of electrical impedance or the relationship between hip and waist measurements, offer additional data of great interest to assess the degree of obesity and the impact it may have on health.