Nutrition American Fitness Magazine Youth Fitness

How to Coach Adolescents on Nutrition Decisions

Sarah Snyder
Sarah Snyder
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Youth exercise professionals are in a powerful position to positively influence eating behaviors. This is when independence begins to be established with regard to food and beverage choices and meal preparation.

Coaches and trainers - even Youth Sports Coaches - often serve as mentors to adolescents, so this population may be receptive to our messages about healthy eating. This can significantly affect well-being—in adolescence and throughout adulthood.

Originally appeared in the Spring 2020 issue of American Fitness Magazine

Why nutrition coaching is so important for youth

Unfortunately, the nutritional needs of adolescents are often overlooked, leaving them at risk for developing unhealthy behaviors. Many adolescents lack basic nutritional and culinary knowledge. 

If you are a certified nutrition coach and have the necessary training required to train youth, then this is a great opportunity to make a huge difference!

Also, their mealtimes are often irregular—because of their busy schedules—and they frequently skip meals. Further, they face potentially negative influences from peers, media, personal food preferences and even family. Combined, these factors can easily lead to excessive consumption of nonnutritive foods (e.g., processed foods and sweetened beverages) along with an inadequate intake of essential nutrients.

This is particularly problematic during this part of the life cycle because adolescent bodies are still growing and developing. As young people move through the stages of prepuberty, active puberty and postpuberty, they undergo specific physiological changes that require additional intake of certain vitamins and minerals.

While some young clients may need specialized nutritional counseling and planning (see “A Few Words on Scope of Practice,” below), most will do well with guidance from coaches and trainers, who can offer simple ways to adopt healthier eating habits.

Supporting the Physiological Changes of Adolescence

Many fitness professionals work with clients in all stages of the life cycle. Here are a few nutritional challenges that are specific to preteens and adolescents:

Energy. Energy needs vary tremendously during adolescence and can range from 1,600 to 3,000 calories per day, depending on factors such as physical activity level and current growth rate (Ellis 2019; Mangieri 2019). Like the onset of puberty, peak height-gain velocity occurs at different ages for different individuals. Typically, growth spurts in adolescent girls begin around 10 years of age and peak at about 12 (Sizer & Whitney 2020). Boys’ growth spurts begin at 12 and peak at about 14 years, finally slowing down around age 19 years (Sizer & Whitney 2020). Specific calorie intake guidelines (ordered by age and activity level) are shown in Table A2-1 in the 2015–2020 Dietary Guidelines for Americans (USDHHS & USDA 2015).

Calcium and vitamin D. Calcium requirements are high during adolescence because of crucial bone development. For males and females ages 9–18, the Dietary Guidelines recommend an intake of 1,300 milligrams of calcium per day. Vitamin D also plays an essential role in supporting rapid bone growth and bone density. Dietary supplementation is often encouraged to ensure that adolescents meet the recommended 600 international units per day (USDHHS & USDA 2015). Unfortunately, sodas and other sugary beverages are often chosen over drinks fortified with calcium and vitamin D, such as nut or animal milk.

Iron. Both male and female adolescents need greater amounts of iron to support an increase in blood volume and the development of lean body mass. Teen girls typically don’t consume as much iron as boys, despite their need to replace losses due to menstruation (Sizer & Whitney 2020). Specifically, males and females ages 9–13 need 8 mg per day, males ages 14–18 need 11 mg per day, and females ages 14–18 need 15 mg per day (USDHHS & USDA 2015).

Avoiding Diet Deficiencies and Unhealthy Excesses in Adolescence

Fewer than 10% of adolescents eat enough fruits and vegetables. This puts youth at risk for problems associated with low dietary fiber and inadequate amounts of micronutrients. Also, 90% of people in this age group consume more than their recommended upper limit of sodium (2,300 mg/day) (CDC n.d.); that increases their risk for electrolyte imbalances. About 40% of adolescents’ daily calorie intake is in the form of “empty calories” from added sugars and fats, found in foods like fast food, pizza, soda and sweets (CDC 2019).

This will not only increase the risk of overweight/obesity but can also lead to poor nutrition overall, as these foods often take the place of nutrient-dense foods. These factors help explain why teens are experiencing higher rates of overweight and obesity, high blood pressure, high blood sugar, type 2 diabetes, and irritable bowel conditions (Chaffin 2019; CDC 2019).

Achieving Health and Fitness Goals During Adolescence

Adolescent clients will have diverse goals regarding sports, weight and health. Here are a few general strategies and sugges­tions for training clients in this age group:

General health. Encourage adolescents to include foods from all food groups daily, including a variety of fruits and vegetables, fat-free and low-fat dairy products, lean proteins, whole grains, and healthy oils.

Weight. While weight loss requires a calorie deficit, adolescents must be careful to consume enough nourishment to support growth and prevent loss of muscle mass. Talk to them about limiting processed foods and controlling portions, and promote mindful eating (e.g., eating meals away from screens). Also recommend they avoid quick fixes like fad diets. Explain that “diet pills” may increase their risk for dehydration or toxicity and have generally not been safety-tested except in adults (NIH 2018).

Sports and/or athletics. Adolescent athletes require more calories and other nutrients than their sedentary peers; however, nutrient needs will depend on the type, intensity and duration of training and competition. Explain this to your athletic clients. For example, if training is focused on building muscle strength and size, clients will need adequate amounts of both carbohydrate and protein to support new muscle growth, in addition to the bone development.

Promoting the Intake of Necessary Nutrients for Youth

The fitness professional can urge adolescents to follow eating behaviors that promote optimal health. For example:

Encourage frequent mini meals and snacks. Eating three mini meals and two or three snacks each day will help adolescents meet their elevated energy needs. Suggest carrying a small cooler with portable items to consume on breaks throughout their day.

Provide simple guidelines. For example, tell clients to eat a rainbow of fruits and vegetables to get an array of nutrients. Also, explain that a well-balanced mini meal includes three things: a low-fat protein, a healthy (whole-grain) carbohydrate, and a serving of fruit or vegetables. Protein and fiber help with satiety between meals. Some possibilities:

  • nut butter, whole-grain crackers, small apple
  • low-fat cheese cubes, air-popped popcorn, cherry tomatoes
  • low-fat cheese and turkey slices, small whole-wheat tortilla, grapes
  • peanut butter, whole-grain bread, fruit preserves

(Shield 2019)

Offer a quick breakfast menu. Suggest easy combinations that won’t disrupt clients’ already-rushed morning routines. Recommend mini meals that are rich in iron, calcium and vitamin C. For instance:

  • low-fat Greek yogurt, granola, berries
  • string cheese, dry whole-grain cereal, banana
  • hardboiled egg, whole-grain toast, fresh fruit
  • high-protein, low-fat granola bar, orange
  • low-fat cottage cheese, unsalted mixed nuts, sliced pears

If clients shy away from veggies, suggest fortified foods. Encourage clients who shun nutrient-dense vegetables, such as dark leafy greens, to supplement their diets with foods fortified with iron, calcium and vitamin D. Whole-grain cereals and 100% juice are two examples.

Involve family members when possible. Advise caregivers in charge of family mealtimes to include whole grains, lean proteins, healthy fats, fruits and vegetables. Refer people to for sound nutritional advice. Also encourage keeping the house stocked with healthy choices for adolescent children and their friends.

Pad your nutritional know-how by exploring more of our nutrition courses. The youths you train will thank you! 

Making Connections With Adolescents

When adolescents first come to you for training, their knowledge of nutrition will depend on school programs, family habits and other factors. It is important to meet young clients where they are and to give them the clarity they need to make independent decisions in the future. Taking a relatable approach when sharing information about healthy eating patterns will help adolescents to absorb it. (See “Screen Time: Use Tech to Promote Healthy Eating,” below, for a few ideas.) Remember: Nutrition education should be fun—for your clients and for you! 

Message in a Bottle: Tips for Boosting Fluids


Adequate fluid intake is vital at every age; however, adolescents often do not meet the standards set by the European Food Safety Authority. Here are a few suggestions to help young clients aim for optimal hydration:

  • Carry a refillable water bottle—and refill it often.
  • Flavor plain water with cucumbers, mint, or fresh fruit such as berries, lemons, oranges or limes.
  • Drink water before, during and after physical activity to prevent heat-related injuries and to maximize athletic performance.
  • For game day and longer training sessions (more than an hour), consider rehydrating with a sports drink that contains carbohydrates, protein and electrolytes.

A Few Words on Scope of Practice

Be sure to keep your scope of practice in mind when working with adolescents. (This, of course, will differ among fitness professionals, some of whom are also registered dietitians or nutritionists.) Always refer adolescents to a registered dietitian or nutritionist if you feel further guidance is necessary or if an existing medical condition, including a food allergy or sensitivity, could affect nutritional status.

As stated by the NASM Nutrition Certification textbook (chapter 2, page 5), “[If] any client has a change in health status, shows an unexplained drop or increase in weight, or shows signs or symptoms of a psychological disorder, the coach must not only recommend that his or her client consult with a professional, but also refuse further sessions until cleared by a licensed healthcare provider.”

The NASM Nutrition Certification program offers an entire four-lesson chapter on the nutrition coach’s scope of practice. Additionally, if you want to get your feet wet in the subject, you can browse all of our CEU courses on nutrition by following this link.

Screen Time: Use Tech to Promote Healthy Eating


Here are a few ways to use today’s tech tools to share nutrition resources with teens and tweens:

  • Share your mobile (work) phone number so they can text you questions and/or pictures of their meals.
  • Help them create a balanced meal with a free app, such as MyPlate from the USDA ( or the free Bam! Dining Decisions app from the CDC (
  • Recommend your favorite free app for tracking foods and beverages.
  • Use your social media posts to demonstrate your own healthy eating habits by sharing photos of your own plate.


Bottin, J.H., et al. 2019. Hydration in children: What do we know and why does it matter? Annals of Nutrition & Metabolism, 74 (3, Suppl.), 11–18.

CDC (Centers for Disease Control and Prevention). 2019. Childhood nutrition facts. Accessed Mar. 13, 2020:

CDC. n.d. Poor nutrition. Accessed Mar. 3, 2020:

Chaffin, M. 2019. Hypertension in children and adolescents. Today’s Dietitian, 21 (2), 42.

Ellis, E. 2019. How many calories does my teen need?  Academy of Nutrition and Dietetics. Accessed Mar. 13, 2020:

NIH (National Institutes of Health). 2018. 10 things to know about dietary supplements for children and teens. Accessed Mar. 3, 2020:

Mangieri, H. 2019. Fueling today’s young athletes. Today’s Dietitian, 21 (4), 24.

Shield, J.E. 2019. When should my kids snack? Academy of Nutrition and Dietetics. Accessed Mar. 3, 2020:

Sizer, F., & Whitney, E. 2020. Chapter 14: Child, teen and older adult. In Nutrition: Concepts and Controversies (15th ed., pp. 543–45). Boston: Cengage Learning.

USDHHS & USDA (U.S. Department of Health and Human Services & U.S. Department of Agriculture). 2015. Appendix 7: Nutritional goals for age-sex groups based on dietary reference intakes & dietary guidelines recommendations. In 2015–2020 Dietary Guidelines for Americans (8th ed., pp. 97–98). Accessed Mar. 2, 2020:

Van Pelt, J. 2015. Hydration in young athletes. Today’s Dietitian, 17 (4), 28.

WHO (World Health Organization). 2018. Guideline: Implementing effective actions for improving adolescent nutrition. Geneva: World Health Organization. License.

Sources: Bottin et al. 2019; Van Pelt 2015.

The Author

Sarah Snyder

Sarah Snyder

SARAH SNYDER, RDN, CPT, is a health coach for a corporate wellness program based in Philadelphia. She has worked with many life-cycle populations and families to develop healthful meals and eating behaviors.


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