New study links early smartphone ownership to health risks

adolescent: Someone in that transitional stage of physical and psychological development that begins at the onset of puberty, typically between the ages of 11 and 13, and ends with adulthood.

average: (in science) A term for the arithmetic mean, which is the sum of a group of numbers that is then divided by the size of the group.

body mass index: (BMI) A person’s weight in kilograms divided by the square of his or her height in meters. BMI can be used to evaluate if someone is overweight or obese. However, because BMI does not account for how much muscle or fat a person has, it is not an accurate measure.

cognitive: A term that relates to mental activities, such as thinking, learning, remembering and solving puzzles.

correlation: A mutual relationship or connection between two variables. When there is a positive correlation, an increase in one variable is associated with an increase in the other. (For instance, scientists might correlate an increase in time spent watching TV with an increase in rates of obesity.) Where there is an inverse correlation, an increase in one value is associated with a drop in the other. (Scientists might correlate an increase in TV watching with a decrease in time spent exercising each week.) A correlation between two variables does not necessarily mean one is causing the other.

depression: (in medicine) A mental illness characterized by persistent sadness and apathy. Although these feelings can be triggered by events, such as the death of a loved one or the move to a new city, that isn’t typically considered an “illness” — unless the symptoms are prolonged and harm an individual’s ability to perform normal daily tasks (such as working, sleeping or interacting with others). People suffering from depression often feel they lack the energy needed to get anything done. They may have difficulty concentrating on things or showing an interest in normal events. Many times, these feelings seem to be triggered by nothing; they can appear out of nowhere.

development: (in biology) The growth of an organism from conception through adulthood, often undergoing changes in chemistry, size and sometimes even shape. (in economics and social sciences) The conversion of land from its natural state into another so that it can be used for housing, agriculture, or resource development.  (in engineering) The growth or change of something from an idea to a prototype.

diabetes: A disease where the body either makes too little of the hormone insulin (known as type 1 disease) or ignores the presence of too much insulin when it is present (known as type 2 diabetes).

focus: (in physics) The point at which rays (of light or heat for example) converge sometimes with the aid of a lens. (In vision, verb, “to focus”) The action a person’s eyes take to adapt to light and distance, enabling them to see objects clearly. (in behavior) To look or concentrate intently on some particular point or thing.

gauge: A device to measure the size or volume of something. For instance, tide gauges track the ever-changing height of coastal water levels throughout the day. Or any system or event that can be used to estimate the size or magnitude of something else. (v. to gauge) The act of measuring or estimating the size of something.

Latinx: An adjective for people from Latin American or having ancestors from there. It is a gender-neutral (or nonbinary) alternative to Latino or Latina.

link: A connection between two people or things.

mental health: A term for someone’s emotional, psychological and social well-being. It refers to how people behave on their own and how they interact with others. It includes how people make choices, handle stress and manage fear or anxiety. Poor mental health can be triggered by disease or might reflect a short-term response to life’s challenges. It can occur in people of any age, from babies to the elderly.

obesity: (adj. obese) Extreme overweight. Obesity is associated with a wide range of health problems, including type 2 diabetes and high blood pressure.

overweight: A medical condition where the body has accumulated too much body fat. People are not considered overweight if they weigh more than is normal for their age and height, but that extra weight comes from bone or muscle.

pediatrics: A field of medicine that has to do with children and especially child health. A doctor who works in this field is known as a pediatrician.

physical: (adj.) A term for things that exist in the real world, as opposed to in memories or the imagination. It can also refer to properties of materials that are due to their size and non-chemical interactions (such as when one block slams with force into another). (in biology and medicine) The term can refer to the body, as in a physical exam or physical activity.

psychologist: A scientist or mental-health professional who studies the mind, especially in relation to actions and behaviors. Some work with people. Others may conduct experiments with animals (usually rodents) to test how their minds respond to different stimuli and conditions.

range: The full extent or distribution of something. For instance, a plant or animal’s range is the area over which it naturally exists. (in math or for measurements) The extent to which values can vary (such as the highest to lowest temperatures). Also, the distance within which something can be reached or perceived.

risk: The chance or mathematical likelihood that some bad thing might happen. For instance, exposure to radiation poses a risk of cancer. Or the hazard — or peril — itself. (For instance: Among cancer risks that the people faced were radiation and drinking water tainted with arsenic.)

smartphone: A cell (or mobile) phone that can perform a host of functions, including search for information on the internet.

symptom: A physical or mental indicator generally regarded to be characteristic of a disease. Sometimes a single symptom — especially a general one, such as fever or pain — can be a sign of any of many different types of injury or disease.