Diabetes #1 : what is diabetes ?

What is diabetes ?

Diabetes, a disease affecting nearly 463 million people worldwide in 2019 [1], is linked to a disorder of the assimilation, use and storage of glucose supplied by food. This results in a high blood glucose level (glycemia): it is called hyperglycemia [2]. But how is glycemia regulated in time? How does diabetes work? What are the different types of diabetes? What are their consequences? We invite you to learn more about this pathology that is emerging as one of the greatest health emergencies of the 21st century.

NB: the blood level of glucose can be called either glycemia or blood sugar

How does the regulation of glycemia work ?

To work properly, the human body needs energy. Food allows to cover these energy needs by providing lipids (fats), protides (proteins) or carbohydrates. These elements are real fuels for the body and are transported by the blood to the organs to ensure that they work as they should. However, to ensure that lipids, protides and carbohydrates do not remain in too high levels in the blood, natural systems act in our body to regulate them.

In order to ensure the good activity of our body, it is important that the blood glucose level, called the glycemia, that mainly comes from carbohydrates, remains constant and moderate (between 0.8 and 1.2 grams per liter of blood). Two hormones produced by the pancreas, insulin and glucagon, help regulate blood sugar levels according to food intake and glucose consumption by the body [3].

In this context, what exactly is diabetes?

When a person has diabetes, the glucose regulation system no longer works properly. The pancreas no longer makes enough insulin. Because the body doesn’t produce enough insulin, the glucose stays in the bloodstream. The patient is then in chronic hyperglycemia, also called: diabetes.

Diabetes is a chronic disease, i.e. a disease of long duration, often associated with disability and the threat of serious complications.

Diabetes is suspected when the blood glucose level is:

• Greater than 1.26g/L on 2 occasions in a fasting state
• Greater than 2g/L at any time of the day [2]

The different types of diabetes

Diabetes is a chronic disease that occurs when the pancreas is no longer able to produce insulin or when the body cannot make good use of the produced insulin. There are three main types of diabetes [4]:

Type 1 diabetes

Also called insulin-dependent diabetes or juvenile diabetes, it usually affects young people before the age of 20 and accounts for 10% of diabetics. This type of diabetes is caused by an autoimmune reaction in which the immune system attacks the β-cells of the pancreas, which produce insulin. The pancreas then produces little or no insulin. As a result, the body can no longer regulate high blood sugar levels properly. Type 1 diabetics require daily injections of insulin, hence the name of the disease: “insulin-dependent diabetes” [5].

Type 2 diabetes

This type of diabetes is non-insulin dependent and generally appears in people between 40 and 50 years of age but can also appear later in older people. It represents most diabetics (90%) and is linked to lifestyle, aging and abdominal obesity. Family history also plays a major role in its appearance. The natural blood sugar regulation system becomes overwhelmed by exposure to large amounts of glucose. The insulin-producing cells of the pancreas become less sensitive to insulin, leading to insulin resistance and/or insulin deficiency. Peak blood glucose levels are therefore less well-regulated [6].

Gestational diabetes

It is characterized by the occurrence of hyperglycemia during pregnancy, at values lower than those leading to the diagnosis of diabetes. Women with this type of diabetes have an increased risk of complications during pregnancy and childbirth. They and their children are also at increased risk of developing type 2 diabetes later in life. It is very often diagnosed during prenatal screening and not because of the occurrence of symptoms [4].

Diabetes symptoms and consequences

Type 1 diabetes is associated with rapid weight loss in contrast to excessive appetite and thirst (polyphagia and polydipsia). Urination is also frequent (polyuria), up to 3-4 L per day.

Symptoms associated with type 2 diabetes are overweight and abdominal obesity.

Chronic hyperglycemia can lead to several long-term complications. These include damage to nerves and blood vessels throughout the body. Untreated or poorly treated diabetes can have adverse effects on the brain, eyes, heart, kidneys and feet [4]

• Brain : risk of stroke, alteration of the nerve structure causing pain and sensitivity deficitis
• Eyes : risk of going blind or having eye damage
• Heart : risk of a heart attack
• Kidney : risk of chronic kidney failure
• Feet : gangrene and/or ulceration leading to foot amputation*

* The major danger of the loss of sensitivity in the foot caused by neuropathy is the risk that an injury may go unnoticed and become infected, leading to amputation of the foot. Special attention should therefore be paid to the diabetic foot [7].

Diabetes in a few figures

• 463 million people have diabetes worldwide [1]
• 1.5 million deaths were directly caused by diabetes in 2019 [1]
• 10% of global health expenditure is spent on diabetes [1]
• 3 out of 4 people with diabetes live in low and middle-income countries [1]

Also :

• 50% of diabetics are not diagnosed [1]
• 20% of diabetics are over 65 years old [1]

Sources :

[1] Atlas du diabète 9^ème édition – Fédération Internationale du Diabète – A télécharger sur  https://diabetesatlas.org/fr/sections/worldwide-toll-of-diabetes.html. Consulté le 19/07/21.

[2] Qu’est-ce que le diabète – Fédération des diabétiques – Disponible sur https://www.federationdesdiabetiques.org/information/diabete. Consulté le 04/08/21.

[3] Les glucides : de l’énergie facilement utilisable – Vidal.fr – Disponible sur https://www.vidal.fr/sante/nutrition/corps-aliments/glucides-energie.html. Consulté le 04/08/21.

[4] Diabète – Organisation mondiale de la Santé – Disponible sur https://www.who.int/fr/news-room/fact-sheets/detail/diabetes. Consulté le 04/08/21.

[5] Diabète de type 1 – INSERM – Disponible sur https://www.inserm.fr/dossier/diabete-type-1/. Consulté le 04/08/21.

[6] Diabète de type 2 – INSERM – Disponible sur https://www.inserm.fr/dossier/diabete-type-2/. Consulté le 04/08/21.

[7] Le pied diabétique – Diabète Québec – Disponible sur https://www.diabete.qc.ca/fr/comprendre-le-diabete/tout-sur-le-diabete/complications/le-pied-diabetique/. Consulté le 04/08/21.