Lack of Energy in Teens

The teenage years are a time of rapid physical and emotional development. Puberty, hormonal fluctuations and rapid growth of bone and muscle can take a toll on energy levels, causing many teens to feel fatigued from time to time. When sleep requirements are not met, lack of energy can progress to full-blown exhaustion. Understanding the nature of fatigue allows teens and their parents to find healthy solutions.


Fatigue in teens is a complex but relatively common phenomenon. Non-organic conditions such as poor sleep, allergies, stress and depression are among the most common causes for lack of energy in teens. Lifestyle factors also play a role. states that only 20 percent of adolescents meet the 9-hour recommendation for sleep during the week, with 45 percent sleeping less than 8 hours each night. Poor diet can also be detrimental; teens who consume too much sugar or caffeine or don't get enough nutrients can have low energy.

Signs and Symptoms

Lack of energy in teens may not always be obvious to onlookers. Some teens complain of fatigue while others are less likely to voice their concerns. Outward signs include frequent yawning, falling asleep during class and other daytime activities, and slow or sluggish movements. Mood-related signs like irritability and low tolerance for stress may also signal chronic tiredness in some instances. Teens who are fatigued often have difficulty concentrating and staying alert during school and other activities. Other symptoms include a heavy sensation in the body, impaired cognition and low mood.


Over time, lack of energy can take a toll on performance and quality of life. According to, over a quarter of high school students fall asleep during school; 22 percent sleep while doing homework and 14 percent miss class or arrive late due to oversleeping at least once weekly. In addition, 73 percent of teens with mood-related problems like anxiety or unhappiness also suffer from insomnia or daytime sleepiness.

While lack of energy can be detrimental to academic performance, it can also threaten the safety of teens in some instances. Sleep-deprived teens who drive are at risk for falling asleep behind the wheel, which greatly increases the likelihood of getting into a motor vehicle accident. Sleeping on the job can also be dangerous when duties involve potentially hazardous tasks like operating heavy equipment.


The only way to treat lack of energy in teens is by uncovering the underlying cause of the condition. A medical evaluation can help pinpoint the factors contributing to fatigue. In most cases, getting 8 or 9 hours of sleep per night is sufficient to prevent excessive tiredness in kids and teens. A healthy diet and regular exercise are vital for preventing obesity, which can also aggravate fatigue. If your teen eats poorly, keep junk food out of the house and encourage snacking on nutrient-rich foods, such as fresh vegetables and whole grains.


Teens who experience severe fatigue that is not relieved by adequate sleep should seek a medical evaluation promptly. A thorough medical history in combination with physical exams like urinalysis or blood tests can help rule out substance abuse and physical disorders like anemia that are known to cause tiredness. In some cases, lack of energy in teens can stem from mental or physical conditions like depression or kidney dysfunction.