Type 2 diabetes is a disease characterised by an increase in blood glucose levels derived from the body’s inability to produce or use its own insulin correctly. Type 2 diabetes mellitus develops in adulthood and so it is sometimes called elderly diabetes. It is the most common form of diabetes (80–90% of all cases).

Diabetes affects millions of people around the world. The Di@bet.es study has shown that diabetes affects 13.8% of the Spanish population (i.e., its prevalence). In other words, 14 out of every 100 people have diabetes. This figure increases with age and it is more common in men than women. Consequently, 20 in every 100 people aged 60–75 years have type 2 diabetes.

Type 2 diabetes (T2D) presents a clear social gradient; people with no education or primary education are twice as likely to develop diabetes as those with a university education, and this trend is the same in both men and women. 

One of the significant problems concerning type 2 diabetes is half of all sufferers are unaware of their condition because they do not present any symptoms in the early stages of the disease. It can only be diagnosed by means of a blood glucose analysis. That is why many people find out they have T2D by chance, while undergoing a routine analysis for another reason. Individuals with very high glucose levels may notice symptoms such as increased thirst, increased urge to urinate and even weight loss.

The main causes of type 2 diabetis in genetically predisposed people are obesity and a sedentary life.

They are at greater risk of developing type 2 diabetes with:

DNA molecule or helix

Genetic factors. A family history of diabetes and cardiovascular disease.

Scale with an arrow pointing upwards indicating a weight increase


Sofa with a box of popcorn

Sedentary habits

A blood vessel with cholesterol in its walls that restricts blood flow

High cholesterol levels (hypercholesterolemia). 

Pregnant woman with a drop symbol on her abdomen

Gestational diabetes. It's a type of diabetes that occurs in 12% of all pregnancies in women with no prior history of diabetes, or women who have had a baby with a birth weight of 4 kg or more.

Person eating a donut

Oral glucose intolerance. These patients present higher than normal blood glucose levels, but they are not high enough to be classified as diabetic. There are two situations considered to be risk factors: if the test result is positive (values ranging between 140 and 199 mg/dL) after swallowing 75 g of glucose; or, if blood glucose levels are high (above 100 mg/dL, but less than 126 mg/dL) after eight hours of fasting.

In every 100 adults, there are around 25–30 individuals with a carbohydrate metabolism disorder (diabetes, whether diagnosed or undiagnosed, glucose intolerance or impaired fasting glucose).

In contrast to type 1 diabetes, people with a high risk of developing type 2 diabetes mellitus can prevent and/or delay the onset if they:

Measuring waist circumference

Maintain a correct body weight by following a healthy eating plan.

Man running; regular physical exercise

Practise regular physical activity (minimum of 150 minutes per week).

Most people are diagnosed with type 2 diabetes by chance while carrying out routine analyses for other reasons (company check-ups, gynaecological tests, etc.). The disease is present but it has not yet produced any symptoms. The early symptoms that induce patients to visit their doctor and which are associated with high sugar levels are: 

Person with the urge to urinate next to the toilet

Frequent urge to urinate (polyuria).

Person drinking a standing glass of water

Increased thirst (polydipsia).

Person eating at table

Increased hunger (polyphagia).

Scale with a down arrow indicating a weight loss

Weight loss.

Tired, sweating man

Other less common symptoms are tiredness, leg cramps and sleepiness.

Type 2 diabetes mellitus is the most common kind, representing roughly 80–90% of all cases, and its onset can be prevented or delayed in the large majority of people. Studies have demonstrated that the risk factors for developing this type of diabetes are, on the one hand, the so-called non-modifiable factors, which are age and genetic predisposition, while on the other hand are the modifiable ones, which are overweight, obesity and a sedentary lifestyle.

If you would like to know your risk of developing type 2 diabetes in the next 10 years, then you can find out by completing the FINDRISK test. Based on your score in this questionnaire, you can identify your degree of risk and which measures to adopt.

This test takes these parameters into account:

Elderly man with a cane

Age. The risk of developing type 2 diabetes is greater in people aged over 45; notwithstanding, cases of type 2 diabetes in obese and sedentary children and adolescents have recently been described.

Line graph

Body mass index (BMI). The BMI is a parameter that relates a person’s weight to their height and helps identify whether they are underweight, normal, overweight or obese. Overweight and obesity are risk factors for developing type 2 diabetes. The BMI is not applicable in the case of children, pregnant women, the very elderly and people with a high muscle mass, such as professional sportsmen and women.

Measuring waist circumference

Waist circumference. The circumference at the waist is an indicator of obesity. In combination with the BMI, it helps determine the risk of cardiovascular disease and type 2 diabetes mellitus. The risk is considered high if the measurement is greater than 102 cm in men and 88 cm in women.

Man running; regular physical exercise

Physical activity. A sedentary lifestyle, both in adults and children, is another risk factor related to the development of type 2 diabetes. Recommendations are to perform regular physical activity, such as 30 minutes walking per day.

Carrot, broccoli and courgette

Eat fruit and vegetables. Doctors advise following a diet rich in fruits and vegetables (2–3 pieces a day) to reduce the risk of developing type 2 diabetes.

Medicines, pills

Medicines used to treat high blood pressure. High blood pressure, an excess of fat in the blood (cholesterol, triglycerides), obesity and diabetes collectively form the condition known as metabolic syndrome. It is important to manage each component independently.

Pregnant woman with a drop symbol on her abdomen

A history of hyperglycaemia or diabetes during pregnancy. Individuals who have experienced elevated blood glucose levels associated with taking certain medicines or, in the case of women, during pregnancy are more likely to develop type 2 diabetes.

Family tree

A family history of diabetes. People with first-degree (parents, siblings, children or grandparents) and also second-degree (aunts/uncles, nephews/nieces) relatives who have a history of diabetes present a greater risk of developing it themselves.

What does my questionnaire score mean? 
Score Risk of developing type 2 diabetes 
Less than 7 Low risk: An estimated 1 in every 100 people will develop type 2 diabetes
7 - 11 Slightly elevated risk: An estimated 1 in 25 people will develop type 2 diabetes
12 - 14 Moderate risk: An estimated 1 in 6 people will develop type 2 diabetes
15 - 20 High risk: An estimated 1 in 3 people will develop type 2 diabetes
Over 20 Very high risk: An estimated 1 in 2 people will develop type 2 diabetes

Diabetes is diagnosed by means of a blood test that determines a person’s blood sugar (glucose) levels. Normal blood glucose values range between 70 and 100mg/dL.

This test analyses whether the analytical indicators are:

  • After fasting: equal to or higher than 126 mg/dL, in two measurements.
  • At any time of the day: equal to or greater than 200 mg/dL accompanied by characteristic symptoms, such as an increased need to urinate or excessive thirst.
  • After taking a glucose solution (75 g): above 200 mg/dL. This test is carried out on individuals whose glucose levels after fasting are between 100 and 126 mg/dL.
  • Glycated hemoglobin (HbA1c): equal to or higher than 6.5%.

Treatment may vary depending on the stage in which the disease was first diagnosed and how it is evolving. Therefore, people with type 2 diabetes will follow different treatment plans:

  • A healthy diet that helps control body weight in combination with regular physical exercise (at least 150 minutes/week) and oral medicines (metformin).
  • If the first treatment is not enough, then the patient’s plan will incorporate new oral or injectable medicines.
  • If the second treatment is insufficient, then insulin might have to be added to the treatment regime.

Oral drugs

Oral anti-diabetic drugs are tablets used to help regulate blood sugar levels. They are taken from the outset of treatment for type 2 diabetes. There are several types and different modes of action; it is, therefore, important that you are familiar with the effects and take them at the times indicated.

Your healthcare team will indicate when you should take them, whether before or after meals, and whether or not they involve the potential risk of producing sugar lows.

Pills with green and white stripes

Sulphonylureas: stimulate an increase in insulin secretion from the pancreas.

Pills with blue and white stripes

Meglitinides: similarly, these also stimulate increased insulin secretion from the pancreas.

Blue, white and green pills

Biguanides: reduce the production of glucose in the liver.

Green, blue and white striped pills

Alpha-glucosidase inhibitors: delay and reduce the absorption of carbohydrates.

Green and white pills

Thiazolidinediones: these decrease insulin resistance.

Pill with prescription meds

SGLT2 inhibitors: these reduce renal glucose reabsorption.

Blue pills

DPP-4 inhibitors: inhibit an enzyme that deactivates incretins, cause an increase in insulin secretion and inhibit glucagon secretion.

The drug of choice in all patients with type 2 diabetes is metformin (a biguanide), unless there is a specific contraindication or the individual presents clear symptoms that their body requires insulin. The metformin’s mechanism of action inhibits natural glucose production in the liver.

Injectable drugs


GLP-1 analogues. These medicines are administered subcutaneously. They increase insulin secretion, inhibit glucagon secretion and delay gastric emptying.


As the years pass, the large majority of people with type 2 diabetes eventually require insulin.

In general, everybody, with or without diabetes, should follow a healthy, balanced and varied eating plan. Eating plans should be customised according to the patient’s age, level of activity, timetable, body weight and personal preferences.


Advice for people with high blood pressure

To prevent and manage high blood pressure, patients must avoid being overweight and complete regular physical exercise. Recommended blood pressure values for people with diabetes are less than or equal to 130/80. In some cases, patients may require treatment and have to follow a salt-free eating plan.

Recomended foods  Unrecomended foods 
Use aromatic herbs and spices to season meals (garlic, parsley, bay leaves, mint, oregano, rosemary, thyme, etc.) Salt, salted foods and any salted sauces (mustard, ketchup, pickles)
Salt-free bread and bakery products Salted bread and bakery products
Salt-free soft cheeses Hard cheeses
Mineral water Sparkling water

Use cooking methods that do not reduce the food’s natural flavour (grilling, steaming, baking, microwaving, baking in foil and frying in olive oil if you are not overweight)

Confectionery and bakery products and any ready-made, pre-cooked or canned/preserved products. 

In cases of severe hypertension, or advanced kidney disease, your healthcare team can provide other specific recommendations and even warn you about foods with a naturally high salt content.

Advice for people with high cholesterol levels


We should all follow a diet that is low in animal fat (butter, lard, cured meats, red meats, etc.).

Blood collection tube

A person with diabetes is advised to maintain their total cholesterol below a level of 200 mg/dL. Values of less than 100 mg/dL are recommended for LDL (bad) cholesterol and greater than 40 mg/dL for HDL (good) cholesterol.

A person lying on a sofa or bed representing sedentary lifestyles

A sedentary lifestyle and being overweight are factors that can lead to an increase in LDL (bad) cholesterol. You may need to take medicines in combination with the dietary recommendations to control your cholesterol levels.


To prevent cholesterol levels from increasing you should try to avoid being overweight, which is a general recommendation for everyone, with or without diabetes.

Physical activity adapted to the abilities of each person and practised regularly can provide a very positive contribution to achieving good control over diabetes, reducing cardiovascular risk factors (obesity, high cholesterol, etc.) and improving one’s sense of mental and physical well-being.

In the case of type 2 diabetes, exercise constitutes an important part of treatment, as do diet and medication (tablets or insulin), and patients must ensure they exercise at least 150 minutes per week.

The exercise should be planned beforehand to avoid an excessive decrease in blood sugar (hypoglycaemia), especially in patients treated with insulin or any other type of medicine that could result in hypoglycaemia.

Collaboration between people with diabetes and their families and healthcare teams is essential for optimizing the treatment and, at the same time, for integrating it into their day-to-day life in terms of regular eating habits, timetables and physical activity.

Therapeutic education in diabetes is a learning process that provides the knowledge and skills required by people with diabetes and their families so they may actively take part in everyday treatment decisions.

Substantiated information by:

Daría Roca Espino
Enrique Esmatjes Mompo
Irene Vinagre Torres
Margarida Jansà Morató
Mercè Vidal Flor

Published: 20 February 2018
Updated: 24 November 2021

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