Dieting in adolescence: What you should know

Teens are exposed to many health messages—which often contradict one another—through mainstream and social media, peers, family, the education system, and in healthcare settings. At a time when they are actively forming their body image and are particularly sensitive to appearance, these messages can affect what they consider a “normal” or “healthy” body, leading them to begin dieting or otherwise attempt to change their body size or shape.

Dieting can be dangerous and is linked to the development of serious health problems, including eating disorders, nutritional deficiencies, and depression. Paradoxically, it often leads to weight gain over time.

Is dieting unhealthy?

Teens are still growing, and they have different nutritional and energy needs than adults. Not eating from all food groups or eating too few calories can have serious impacts on their growth and long-term health.

While some begin dieting with the goal of becoming “healthier,” most say being unhappy with their body and wanting to be thinner are their main motivations.

Dieting means different things to different people. Teens who diet might:

• make choices like eating more fruit, vegetables and fibre, and cutting down on fast food, or
• make choices like skipping meals, eating less, or not eating certain types of food.

Dieting can make teens feel:

• hungry and preoccupied with food.
• distracted and tired.
• sad and unmotivated.
• cold and dizzy.
• deprived.

In girls, dieting can lead to irregular or absent periods and loss of bone density, even without significant weight loss.

Who is at risk?

Although adolescents considered overweight or obese are at higher risk, dieting is common in the teenage years no matter their weight or body shape. By grade 8, about half of adolescents have tried to lose weight. Some other risk factors that are associated with dieting include:

• Low self esteem
• Body dissatisfaction (e.g., wishing to be thinner or more toned)
• Early puberty
• Engaging in high-risk behaviours (e.g., substance use, unprotected sex)
• Following special or fad diets (e.g. keto, paleo)
• Involvement in weight-focused sports
• Weight-related bullying or maltreatment
• Using social media for more than two hours per day, especially for younger adolescents

What can I do?

• Talk to your teen about why they are dieting and how it is affecting them, be open and nonjudgmental.
• Model a healthy relationship with food and satisfaction with your body.
• Make sure they know that healthy individuals come in every shape and size.
• Have regular family meals that include all the food groups. Canada’s Food Guide can be a helpful tool.
• Instead of labeling foods as “good” or “bad”, normalize balanced eating that includes a wide variety of foods.
• Support your teen in making healthy and sustainable lifestyle choices, like group-based physical activities and good sleep habits, rather than focusing on weight loss.
• Praise your teen for all their positive attributes, not just their appearance, and avoid commenting on their weight.

When should I talk to a health care provider?

It is common for teens to feel self-conscious, but always feeling bad about their bodies, worrying about weight, or feeling guilty when they eat is not normal or healthy. Reach out to your healthcare provider if you notice any of the following signs or are concerned about your teen’s wellbeing:

• A dramatic change in their eating habits
• Physical changes, such as weakness, frequent headaches, or dizziness
• Eating in secret
• Avoiding activities because of food or obsessive exercise
• Fear of food
• Vomiting after meals
• Using laxatives
• Irregular periods or loss of periods
• Not gaining weight from year to year