By Elizabeth Valdes
What is a Calorie?
A calorie is a unit of energy. It is not a measure of weight, nutrient density, or a number to fear when viewing food labels. In actuality, the calories printed on the back of goods are scientifically known as kilocalories (kcals). According to Grace Derocha, a registered dietitian, one kcal is the energy required to heat 1 kilogram of water by 1 degree Celsius.
How Are Calories In Foods Measured?
The answer is a method called direct calorimetry. To determine the number of calories per serving within a food item, a sample of it is burned. The sample is placed in an oxygen-filled chamber surrounded by water, called a bomb calorimeter, and is incinerated. The change in temperature as it rises reveals how many calories are in the food. For instance, if the temperature of the water increases by 50 degrees, the sample contains 50 calories.
The Atwater Indirect System
The Atwater Indirect System is a commonly used way for food scientists to determine the amount of calories in a new food product. Foods can have ingredients that burn in a calorimeter, but aren’t necessarily released and absorbed into the bloodstream. When this occurs, manufacturers add up the calories that come from the energy-containing nutrients—protein, carbohydrates, fats, and alcohol—to determine calories using this system.
According to the Atwater system, the average values for proteins, carbohydrates, fats, and alcohol are 4 Kcal/g, 4 Kcal/g, 9 Kcal/g, and 7 Kcal/g respectively. Therefore, when the back of a 45-gram granola bar reads 230 calories, it is calculated by its 3 grams of protein, 29 grams of carbohydrates, and 12 grams of fat.
Adolescents and the Importance of Food Knowledge
A balanced diet is imperative for everyone, especially teenagers who are in the process of growing. The amount and what kind of food you consume greatly affects the hormones in the anterior pituitary gland of your brain, which controls hGH, or the growth hormone. Consuming an adequate amount of protein, lipids, and carbohydrates impacts daily moods and levels of energy. Eating an unbalanced meal throughout a person’s adolescent period has possible long-lasting effects of stunting the growth of your skeletal muscles, long bones, and your final body size.
Eating disorders are a variety of mental health conditions defined by issues with eating behaviors and convoluted thoughts related to food, eating, weight, or shape. Eating disorders limit a person’s capacity to complete daily tasks and hinder their ability to balance their emotional and physical health.
Adolescents are affected by these disorders at startlingly high rates. According to the most recent study from the National Institute of Mental Health, 2.7% of teenagers will experience a form of disordered eating. It becomes more apparent as food science progresses that being educated on what a calorie is, dangers of disordered eating, and the importance of a cohesive diet is vital to our youth and future generations’ health.
Resources:
Fantozzi, J. (2018, June 13). How Are Calorie Counts Calculated? Livescience.com; Live Science
Rittenhouse, M. (2021, August 4). Eating Disorders in Teens. Eating Disorder Hope.
Schwarcz, J. (2018, September 6). How is the caloric value of food determined? Office for Science and Society.
Table: How Are Calories in Foods Measured? (n.d.). Merck Manuals Consumer Version.
Rawindraraj, A. Basit, H. Jialal, I. (2023, May 1). Physiology, Anterior Pituitary. National Library of Medicine.
Astra Stem 
Leave a comment