A group or risk population is made up of those people who, due to certain characteristics, whether biological, physical or social, have a greater probability of contracting certain diseases, suffering from poisoning or accidents. These characteristics are called "feeling before contracting a disease."[1]​.

There are numerous risk groups based on its cause. An important risk factor is poverty since low-income people (poor) cannot adequately satisfy their diet and this causes malnutrition that could lead to death.

• - Risk groups are considered to be those people who, due to their age or physical condition, may be more vulnerable to contracting certain diseases, such as babies, children, pregnant women, breastfeeding women, the elderly, obese, diabetics, etc.[2]​[3]​.

• - High-risk people are also considered those who handle dangerous machines, such as dangerous goods truck drivers), airplane pilots or those who perform very stressful jobs.

• - Another risk group is made up of people who ingest addictive and harmful toxic substances such as tobacco, alcohol, drugs, etc. These people are prone to heart problems.[4]​.

• - Study conditions").