Written by Nutritionist, Tamara Walker. Email a Nutritionist today via the educational support page. 

Many young athletes and parents worry that eating fat will automatically lead to weight gain. Foods such as nuts, eggs, avocado, olive oil, and full-fat dairy products are sometimes avoided because they are considered “fattening” or too high in calories.

However, nutrition science shows that dietary fat itself does not cause an increase in body fat. Changes in body composition occur when energy intake consistently exceeds energy expenditure over time, regardless of whether those calories come from fat, carbohydrates, or protein [1,2].

For young athletes, dietary fat is not something to fear or restrict unnecessarily. It is an essential nutrient that supports growth, hormone production, brain development, immune function, vitamin absorption, and recovery from training [2,3,6].

A balanced diet containing appropriate amounts of healthy fats helps young athletes meet the demands of both sport performance and normal development [3].

What Is Dietary Fat?

Dietary fat is one of the three macronutrients, alongside carbohydrates and protein. It provides approximately 9 calories per gram, making it the most energy-dense nutrient [5].

Although carbohydrates are the body’s preferred fuel source during high-intensity exercise, fat performs many important functions that cannot be replaced by other nutrients [2,8].

Dietary fat helps with:

·      Maintaining healthy cell membranes

·      Producing hormones involved in growth and development

·      Absorbing fat-soluble vitamins (A, D, E, and K)

·      Supporting brain and nervous system development

·      Maintaining immune function

·      Regulating inflammation

·      Providing energy during lower-intensity exercise and daily activities [6,7,9]

For children and teenagers, these roles are especially important because their bodies are still growing while adapting to the physical demands of training [3].

Does Eating Fat Make You Gain Body Fat?

This is one of the most common misunderstandings in nutrition.

The body does not store dietary fat as body fat simply because a food contains fat. Body composition is mainly influenced by long-term energy balance. This is the relationship between energy consumed through food and energy used through metabolism, growth, daily movement, and exercise [1].

If someone consistently consumes more energy than their body needs, the excess energy can be stored as body fat. This can happen from excess intake of any macronutrient:

·      Excess carbohydrates can contribute to fat storage.

·      Excess protein can contribute to fat storage.

·      Excess fat can contribute to fat storage.

The key factor is total energy balance, not whether fat is included in the diet [1,2].

For young athletes, this distinction is especially important because they often have higher energy requirements due to both growth and regular training [3].

Why Young Athletes Need Dietary Fat

1. Fat Supports Growth and Development

Young athletes are not only training, they are growing.

During childhood and adolescence, the body requires enough energy and nutrients to support:

·      Bone growth

·      Muscle development

·      Puberty

·      Tissue repair

·      Hormonal changes [3]

Dietary fat provides essential fatty acids, including omega-3 and omega-6 fatty acids, which the body cannot produce and must obtain from food [6].

Very low-fat diets can make it harder for young athletes to consume enough energy and may reduce intake of important nutrients required for growth and recovery [3,4].

2. Fat Supports Hormone Production

Hormones play an essential role in growth, athletic development, and recovery.

Dietary fat contributes to the production of steroid hormones involved in:

·      Growth

·      Puberty

·      Reproductive health

·      Muscle adaptation

·      Recovery from exercise [3,6]

This is particularly important in youth sport, where some athletes may feel pressure to become lighter or leaner in an attempt to improve performance.

However, consistently restricting calories or dietary fat can contribute to low energy availability. This occurs when the body does not have enough energy remaining after exercise to support normal physiological functions [4].

Low energy availability is associated with:

·      Reduced bone health

·      Hormonal disruption

·      Poor recovery

·      Increased injury risk

·      Reduced performance [4]

Young athletes need enough fuel to support both training and healthy development [3,4].

3. Fat Supports Brain Development and Performance

Sport is not only physical. Young athletes rely on concentration, decision-making, reaction time, and learning new skills.

The brain contains a high proportion of lipids, and omega-3 fatty acids, particularly docosahexaenoic acid (DHA), play an important role in brain development and function [7].

Adequate intake of healthy fats supports:

·      Brain development

·      Memory

·      Concentration

·      Learning

·      Nervous system function [7]

For student-athletes, good nutrition supports performance both in competition and in the classroom.

4. Fat Helps Absorb Essential Vitamins

Some vitamins require dietary fat for effective absorption.

These include:

Vitamin A

Supports vision, immune function, and cell growth.

Vitamin D

Important for bone health, muscle function, and immune regulation.

Vitamin E

Acts as an antioxidant and helps protect cells.

Vitamin K

Supports blood clotting and bone metabolism.

Without sufficient dietary fat, the body cannot absorb these vitamins efficiently [6].

For example, adding olive oil to vegetables or including avocado with a salad can improve the absorption of certain nutrients.

Fat and Sports Performance

Carbohydrates are the main fuel source for high-intensity activities such as football, rugby, hockey, swimming, and athletics.

However, this does not mean fat is unimportant.

Fat contributes to energy production during:

·      Lower-intensity exercise

·      Longer-duration activity

·      Recovery periods

·      Normal daily movement [8]

Fat also provides a concentrated source of energy, which can be helpful for young athletes with demanding training schedules.

A teenager who trains several times per week may have significantly higher energy requirements than a less active young person. Removing healthy fats unnecessarily can make it more difficult to meet these needs and support recovery [3,8].

Choosing the Right Types of Fat

The goal is not to remove fat from the diet. The goal is to choose nutrient-rich sources of fat more often.

Healthy Unsaturated Fats should make up the majority of dietary fat intake.

Good sources include:

·      Olive oil

·      Rapeseed oil

·      Avocado

·      Nuts

·      Seeds

·      Nut butters

·      Salmon

·      Trout

·      Sardines

·      Mackerel

·      Eggs

These foods provide essential fatty acids, vitamins, and other beneficial nutrients that support health and performance [6,9].

Omega-3 fatty acids, found in foods such as oily fish, are particularly important because they play roles in inflammation regulation, cardiovascular health, and normal development [9].

What About Saturated Fat?

Saturated fats are found in foods such as:

·      Butter

·      Cheese

·      Fatty cuts of meat

·      Pastries

·      Some processed foods

These foods do not need to be completely eliminated. However, young athletes should aim for a diet where most fat intake comes from nutrient-rich sources of unsaturated fats.

Current evidence suggests that the overall quality of the diet is more important than focusing on one nutrient in isolation [10].

A balanced approach allows young athletes to enjoy a variety of foods while still supporting health and performance.

How Much Fat Should Young Athletes Eat?

Sports nutrition guidelines generally recommend that fat contributes approximately 20–35% of total daily energy intake for healthy children, adolescents, and athletes [3,5].

The ideal amount depends on:

·      Age

·      Body size

·      Growth stage

·      Training volume

·      Sport demands

·      Overall energy requirements

Very low-fat diets are generally not recommended for young athletes because they may make it harder to meet energy needs and obtain essential nutrients required for growth and recovery [3,4].

The focus should be on adequate energy intake and choosing a variety of nutrient-rich fat sources.

Common Questions Parents Ask

“Should my child avoid fat before training?”

Not necessarily.

Large amounts of fat immediately before intense exercise may slow digestion and cause discomfort for some athletes. However, healthy fats should still be included regularly throughout the day as part of a balanced diet [2,3].

Examples of balanced meals:

2–3 hours before training:

·      Wholegrain toast with eggs and avocado

·      Chicken and avocado wrap

·      Pasta with vegetables and olive oil

After training:

·      Greek yoghurt with nuts and fruit

·      Milk smoothie with peanut butter

·      Salmon with rice and vegetables

“Are low-fat products healthier?”

Not always.

Some reduced-fat products can be useful, but others replace fat with added sugar or refined carbohydrates to improve taste and texture.

Parents should focus on the overall nutritional value of foods rather than whether a product is labelled “low-fat” [10].

A food being lower in fat does not automatically make it healthier.

Practical Tips for Parents

Parents can support young athletes by:

·      Including healthy fats at meals and snacks

·      Avoiding unnecessary restriction of food groups

·      Teaching children that food provides fuel for growth and performance

·      Focusing on overall dietary patterns rather than individual nutrients

·      Encouraging variety and balance

A well-fuelled young athlete’s diet should include:

Carbohydrates → energy for training and competition

Protein → muscle repair and adaptation

Healthy fats → hormones, health, and recovery

Fruit and vegetables → vitamins, minerals, and antioxidants

A balanced eating pattern helps young athletes perform well while supporting long-term health and development [2,3].

Key Takeaways

Fat does not make young athletes fat.

Dietary fat is an essential nutrient that supports:

·      Growth and development

·      Brain function

·      Hormone production

·      Vitamin absorption

·      Immune health

·      Recovery from training [3,6,7]

The goal for young athletes is not a low-fat diet. The goal is a balanced diet that provides enough energy and includes a variety of nutrient-rich foods.

Healthy fats such as nuts, seeds, oily fish, avocado, olive oil, and eggs are valuable parts of sports nutrition and should be included as part of a well-balanced eating pattern [3,6,9].

For young athletes, the message is simple:

Don’t fear fat...fuel with it.

This article was written by Nutritionist Tam. Youth Sport Nutrition offers 1-2-1 sessions specifically for young athletes and their families, including a free initial consultation call. You can book a 1-2-1 today.

Disclaimer: This article is intended to provide general information about nutrition for youth athletes and is not meant to replace professional dietary advice or individual nutritional counselling. Every child's nutritional needs can vary due to factors such as age, size, physical activity level, and medical conditions. We strongly recommend consulting with a registered dietitian or a healthcare provider before making changes to your child's diet, such as adding food powders. YSN and the author of this article do not take responsibility for any possible consequences from any treatment, procedure, dietary modification, action, or application of medication which results from reading or following the information contained in this article.

References

[1] Hall KD, Heymsfield SB, Kemnitz JW, Klein S, Schoeller DA, Speakman JR. Energy balance and its components: implications for body weight regulation. American Journal of Clinical Nutrition. 2012;95(4):989–994.

[2] Thomas DT, Erdman KA, Burke LM. Nutrition and Athletic Performance. Medicine & Science in Sports & Exercise. 2016;48(3):543–568.

[3] Desbrow B, McCormack J, Burke LM, et al. Sports Nutrition for the Adolescent Athlete. International Journal of Sport Nutrition and Exercise Metabolism. 2014;24(5):570–584.

[4] Mountjoy M, Sundgot-Borgen J, Burke L, et al. IOC Consensus Statement on Relative Energy Deficiency in Sport (RED-S): 2018 Update. British Journal of Sports Medicine. 2018;52(11):687–697.

[5] Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids. Washington, DC: National Academies Press; 2005.

[6] Calder PC. Functional roles of fatty acids and their effects on human health. Journal of Parenteral and Enteral Nutrition. 2015;39(1 Suppl):18S–32S.

[7] Cunnane SC. The importance of dietary lipids for human brain development. Annual Review of Nutrition. 2005;25:159–193.

[8] Jeukendrup AE. Periodized nutrition for athletes. Sports Medicine. 2017;47(Suppl 1):51–63.

[9] Calder PC. Omega-3 fatty acids and inflammatory processes: from molecules to man. Biochemical Society Transactions. 2017;45(5):1105–1115.

[10] Astrup A, Magkos F, Bier DM, et al. Saturated fats and health: a reassessment and proposal for food-based recommendations. Journal of the American College of Cardiology. 2020;76(7):844–857.