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2.8. Eating-related illnesses

Eating-related illnesses

In this video you can see some practical advice on how eating should be to try to avoid diseases related to eating that we are going to explain.

Although the mediterranean diet has been the traditional diet in a country like Spain, in recent years our eating habits have changed, which has caused an increase in diet-related diseases. Some of these diseases are:


The obesity is excess body fat leads to a high weight of the body. It is the most important health problem in developed countries.

There are many causes of obesity, such as genetic inheritance, the functioning of the nervous system, the endocrine system, or the lifestyle that the person leads. But they can be reduced to two:

  • Eating more calories than the body consumes.
  • Not doing enough physical activity for the proper functioning of the body .

If the person takes in more calories than he expends, they accumulate as fat. If the person needs more energy than he takes in, he takes the fat he has accumulated. Thus, obesity is produced by the intake of an excess of calories.

Obesity reduces the life of the person and is the cause of other diseases such as diabeteshypertension, coronary heart disease, respiratory problems, back pain, gout, osteoarthritis, etc.

La obesidad es una enfermedad que podemos evitar cuidando nuestra dieta

 La obesidad es una enfermedad que podemos evitar controlando nuesta dieta.

The body mass index (BMI) is a formula that allows us to know if our weight is normal according to our mass and height.

It should be noted that these results are only valid for adults, since the same BMI values ​​cannot be applied in children and adolescents due to their constant growth in height and body development.

It must also be said that the BMI has its limitations, since it can indicate that very tall people are "overweight" without having excess fat, while the lowest can have excess fat and "not be overweight", according to the table. It also does not differentiate between muscle mass and fat, so a very muscular person can be "overweight", according to the table.

WHO classification of nutritional status according to BMI


BMI (kg/m²)

 Under weight


     Severe thinness


     Moderate thinness

16.00 - 16.99

     Slight thinness

17.00 - 18.49


18.5 - 24.99




25.00 - 29.99



          Mild obesity

30.00 - 34.99

          Medium obesity

35.00 - 39.99

          Morbid obesity


Calculate your BMI

Mass in kilos: 

Height in centimeters 

Body Mass Index (BMI) = 12,500

Statistics: Obesity in Spain (INE), by Autonomous Community  and by sex .

Curiosity: Unreal models in advertising: Dove evolution.

Answer in your notebook

2.10.- What measures would you take to avoid obesity?

Mellitus diabetes

Although we will talk about diabetes when we see diseases of the endocrine system, due to its relationship with food, we will also name it now.

  • The type 1 diabetes occurs because the pancreas does not make insulin. It cannot be prevented and, although it also occurs in adults, it has a higher incidence in children and young people.
  • The type 2 diabetes, or non - insulin is the most common type of diabetes, and mainly in adults. Unlike type 1 diabetes, it can be prevented.

It occurs because insulin does not work properly, and glucose cannot enter the cells of the tissues (liver and muscles), so it accumulates in the blood causing diabetes.

It can be prevented with physical exercise and a healthy and balanced diet, eliminating energy foods rich in carbohydrates and fats from the diet. In this way, by avoiding being overweight, we can prevent type 2 diabetes. Current lifestyles are leading to a higher incidence of this type of diabetes.


The atherosclerosis is the deposition of plates, called atheromas, in the walls of arteries.

The atheromas are formed, mainly cholesterol (lipids and also other calcium). They make it difficult for the blood to circulate and can even clog the arteries. If the blood cannot reach the heart, it can cause angina pectorisheart attacks, etc. If any piece of plaque is detached, it can travel through the artery to reach smaller vessels and block them (embolism).

It can cause very serious illness, even death, but it can be avoided with healthy habits. Not smoking, exercising regularly, changing the consumption of animal fats for vegetable fats, controlling stress,… will help us avoid atherosclerosis. For this reason, although it is a disease of the circulatory system, we have seen it in this topic because of its relationship with food.

Placas de colesterol

By The original uploader was Grahams Child at English Wikipedia. Later versions were uploaded by Jrockley at en.wikipedia. Image uploaded in Commons by Maderibeyza and translated from English to Spanish by Linfocito B. (Endo dysfunction Athero.PNG) [GFDL or CC-BY-SA-3.0], via Wikimedia Commons

Celiac disease

The celiac disease is a disease caused by damage to the lining of the small intestine caused by a protein called gluten, found in wheat, rye and barley mainly and foods produced with these ingredients.

Gluten produces an autoimmune reaction that causes inflammation of the small intestine causing it to not absorb nutrients from food normally.

The symptoms of celiac disease can vary from one person to another, but the most common are diarrhea , weight loss, abdominal pain, fatigue, as well as delayed growth in children.

The most effective treatment is following a strict diet with foods that do not contain gluten.


Eating disorder

Eating disorders include several chronic diseases that, although manifested by eating behavior, are diseases of the nervous system, characterized by a distortion of body image and an obsession with weight control.

Un chica de delgadez extrema está tumbada en un sofá.

By Angie vite (Own work) [CC BY-SA 4.0], via Wikimedia Commons


The bulimia is a disorder of eating behavior characterized by excessive preoccupation with weight and shape, lack of self - control in food, which makes ingests person large amounts of food in a short period of time (binges) and then try to make up for it by vomiting or taking weight loss drugs, laxatives, or diuretics to help you eliminate what you have eaten.

Anorexia nervosa

The anorexia is a disorder characterized by an intense fear of gaining weight and a distorted perception of one's body that makes people always look obese even if extreme thinness.

The anorexic person tries to reduce their weight as it is, eating the least, doing a lot of exercise,… so it can become a very serious disease that can cause the death of the person.


The vigorexia or muscle dysmorphia is a disorder that is not strictly food, but where there is also an obsession with the figure of a distortion of his body. It is more common in young men, but it also affects women.

The vigorexia can manifest itself in two ways: extreme physical activity, and compulsive eating to gain weight by having the perception of being too thin.

By Papakhios (Own work) [Public domain], via Wikimedia Commons

Game: Nutritional and eating diseases. (No need to register to play)

Activity: Food crossword.

ThatQuiz: Human food.

Answer in your notebook

2.12.- What is the difference between anorexia and bulimia?


In addition to eating disorders, people can become undernourished due to other problems:


The cachexia is a state of extreme malnutrition, muscle atrophy, fatigue, weakness and anorexia in people who are not actively trying to lose weight. It can be a symptom of a disease such as cancer, tuberculosis, AIDS, etc. 


The marasmus produces emaciation due to an insufficient supply of nutrients, which causing energy deficiency.


By Photo Credit:Content Providers(s): CDC/ Don Eddins [Public domain], via Wikimedia Commons


The kwashiorkor is a disease that occurs in children who do not take enough protein in the diet. The baby receives essential amino acids through breast milk, but when they stop drinking milk, in countries where they go hungry, their diet becomes rich in carbohydrates but deficient in protein.

The name kwashiorkor comes from one of the Ghanaian languages, and means "the one who moves" referring to children who have been breastfed and who leave breastfeeding when another new sibling has been born.

The most characteristic symptoms of kwashiorkor are abdominal bulging, reddish hair coloring, and skin depigmentation. The low level of protein in the blood causes the osmotic pressure to be reduced and fluids pass from the capillaries to the abdomen, causing inflammation.

Niña enferma con kwashiorkor

By Dr. Lyle Conrad [Public domain], via Wikimedia Commons


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