Fats: The Most Misunderstood Nutrient
Why growing children need dietary fat—and why the whole pattern matters more than fear
At the end of a London school day, food decisions can become rushed. A child may eat at school, travel across the city and arrive at gymnastics before the family evening meal. At the same time, adults are surrounded by labels and messages that describe food as “low fat”, “light” or “healthy”.
It is easy for one idea to take over: fat must be something to avoid.
For a growing child, that conclusion is too simple. Dietary fat provides energy and essential fatty acids. It is part of cell structures and helps the body absorb fat-soluble vitamins. The important question is not whether a child’s food contains fat, but how the whole diet supports growth, learning, activity and health over time[1].
This chapter explains what fat is, why different fatty acids are discussed differently, and how official guidance can be used without turning meals into a calculation. It is written for families of recreational gymnasts—not as a diet plan, medical assessment or performance programme.
Food supports growth, learning and movement.
Carbohydrate is an important source of energy.
Protein provides amino acids for growth and renewal.
Dietary fat provides energy and essential fatty acids, and the types of fat still matter.
Food, Growth & Gymnastics
No Nutrient Works Alone
The whole meal
Food rarely arrives as one nutrient. Yoghurt contains carbohydrate, protein and fat. A lentil dish may provide carbohydrate, protein, fibre and a cooking fat. Bread with egg or hummus is not a single-nutrient food either.
That matters because children do not need a competition between carbohydrate, protein and fat. Each has different roles, and the body handles them within the same growing system.
Fat provides about 9 kilocalories per gram, compared with about 4 for protein and 3.75 for carbohydrate[1]. That is a description of energy density—not an instruction for families to count calories. A more energy-dense nutrient is not automatically “bad”, just as a less energy-dense food is not automatically more suitable for a particular child.
Different roles, shared meals
- Carbohydrate is an important source of energy for the brain and active muscles.
- Protein supplies amino acids used to build and renew tissues and produce many working substances in the body.
- Fat supplies energy, provides essential fatty acids and helps carry fat-soluble vitamins.
The UK Eatwell Guide presents balance across a day or even a week, rather than demanding that every plate looks identical[2]. That approach fits real family life. School meals vary. Appetites change. Training days and quieter days feel different. The goal is a reliable overall pattern, not a perfect photograph of every meal.
Food, Growth & Gymnastics
What Dietary Fat Actually Is
Inside dietary fat
The words fat and fatty acid are often used as if they mean exactly the same thing. They are related, but not identical.
Most dietary fat is present as triacylglycerol, also called triglyceride: three fatty acids attached to a glycerol backbone[1]. The characteristics of a fat depend partly on the fatty acids it contains.
Fatty-acid families
- Saturated fatty acids contain no carbon-to-carbon double bonds.
- Monounsaturated fatty acids contain one double bond.
- Polyunsaturated fatty acids contain more than one double bond.
These structural differences affect physical properties and biological behaviour. They also explain why one word—fat—can cover several related substances.
Most foods are mixtures. Olive oil is known for monounsaturated fat but also contains saturated and polyunsaturated fatty acids. Butter contains several types too. Fish, eggs, nuts, seeds, dairy foods and meat each contain their own mixtures. It is therefore more accurate to say that a food is higher in a particular type of fat than to pretend it contains only that type.
Some unsaturated fatty acids can also have a trans configuration. Naturally occurring trans fats are present at low levels in some foods, while industrial processes can produce others. Current guidance recommends keeping trans-fat intake low and choosing dietary patterns in which fats are mainly unsaturated[1, 3].
Food, Growth & Gymnastics
Why a Growing Body Needs Fat
MATTERS
Growth and development
Fat has several ordinary biological roles. None makes it a miracle nutrient; together, they explain why it should not be treated as something a growing child can simply remove.
Energy
Fat is a concentrated source of energy. The body can use fatty acids for energy and store energy in adipose tissue for later use. This is normal physiology, not a judgement about a child’s shape.
Essential fatty acids
Two polyunsaturated fatty acids are described as essential because the body cannot make them: alpha-linolenic acid, an omega-3 fatty acid, and linoleic acid, an omega-6 fatty acid[1]. They can contribute to pathways that produce other physiologically important fatty acids.
Cells and communication
Lipids form important parts of cell membranes. They also take part in signalling and many normal processes. Cholesterol, for example, is found in cells and is used to make hormones, vitamin D and substances involved in digestion[4]. The body makes the cholesterol it needs.
Fat-soluble vitamins
Dietary fat supports the absorption of fat-soluble vitamins. Vitamins A, D, E and K are classified as fat-soluble and are absorbed and transported in association with fats[5]. Detailed discussion of these vitamins belongs in the next chapter of this series.
Food, Growth & Gymnastics
What Gymnastics Adds
Gymnastics and the week
A recreational gymnastics class may last an hour, but the child arrives carrying the rest of the day: breakfast, school, lunch, play, travel, emotions and whatever food was available after the final bell.
Dietary fat contributes to the overall pattern that supports growth and activity. Gymnastics mixes effort of different intensities, and no single nutrient explains or fuels the whole class.
Timing and comfort
A larger or richer meal immediately before vigorous activity may feel less comfortable for some children. That does not make foods containing fat unsuitable; it means timing and individual tolerance can matter. Children differ in appetite, routine and digestive comfort.
An ordinary school-to-gym rhythm
- Before school: a familiar breakfast containing a mixture of nutrients.
- During school: lunch and drinks that form part of the day’s overall intake.
- Before gymnastics: if needed, a practical familiar snack selected for time, appetite and comfort.
- After class: the family returns to the wider evening meal and normal routine.
This is not a meal plan. It is a reminder that one snack cannot carry the nutritional responsibility for an entire day. A broad review of young-athlete nutrition emphasises adequate overall intake, sustainable habits and caution around performance supplements[6]. It is a narrative review centred on adolescent athletes rather than a study of primary-school recreational gymnasts, so it should not be turned into precise instructions for this audience.
Food, Growth & Gymnastics
Population Guidance, Not a Child Target
How to read the numbers
Official nutrition documents often express fat recommendations as a percentage of energy intake. That language can look like a personal formula, but UK dietary reference values for fats are designed mainly as population averages, not precise individual prescriptions[1].
Current UK guidance states that:
- saturated fatty acids should provide an average for the population of no more than 10% of energy excluding ethanol;
- total fat should provide an average for the population of no more than 35% of energy excluding ethanol;
- most UK fat recommendations apply from around two years of age[1].
Those figures allow governments and researchers to monitor population patterns. A family does not need to calculate the percentage of energy from fat in a child’s lunchbox, nor does one day above or below an average establish a problem.
Why quality remains important
Population guidance is not meaningless simply because it is not a personal target. SACN and WHO both support reducing saturated and trans fats within the overall diet and favouring appropriate replacements, particularly unsaturated fats[3, 7]. This is a pattern-level message.
For families, the practical translation is usually simpler: include varied foods, use unsaturated oils and spreads as the usual cooking or spreading choices where suitable, include oily fish or appropriate alternatives, and avoid treating foods high in saturated fat as the foundation of every meal[2].
Food, Growth & Gymnastics
Not All Fats Are the Same
Fatty-acid families
| Family | What the term means | Familiar sources | Calm interpretation |
|---|---|---|---|
| Saturated | Fatty acids with no carbon-to-carbon double bonds | Butter, ghee, cheese, fatty meat, coconut and palm oils, cakes and pastries | These foods can fit within varied diets, but current guidance recommends limiting the population average and replacing some saturated fat with unsaturated fat[3, 7]. |
| Monounsaturated | Fatty acids with one double bond | Olive and rapeseed oils, avocado and several nuts | Useful sources of unsaturated fat; the whole food and overall pattern still matter. |
| Polyunsaturated | Fatty acids with more than one double bond | Oily fish, walnuts, seeds and several vegetable oils | Includes omega-3 and omega-6 families. Two fatty acids are essential[1]. |
| Trans | Unsaturated fatty acids with a trans configuration | Small natural amounts in ruminant foods; some industrially produced fats | UK intake is generally low, but international guidance recommends keeping intake very low[1, 3]. |
Replacement is more informative than removal
When public-health guidance advises reducing saturated fat, the replacement matters. Replacing some saturated fat with unsaturated fat has a different nutritional meaning from simply removing food and leaving the child with less energy or a narrower diet. SACN’s evidence review supported replacing saturated fats with unsaturated fats, while WHO also identifies unsaturated fats and fibre-containing carbohydrate foods as appropriate replacements[3, 7].
This does not require every household to use the same cuisine. Olive oil, rapeseed oil, sunflower oil, nuts, seeds, fish, avocado and many mixed dishes can contribute unsaturated fats. Cultural foods should be understood in context rather than sorted into a moral list.
Food, Growth & Gymnastics
Omega-3 and Omega-6
Frequently marketed, often misunderstood
Omega-3 and omega-6 are names for two families of polyunsaturated fatty acids. The number refers to the location of the first double bond when counted from one end of the fatty-acid chain[1].
The essential starting points
Alpha-linolenic acid (ALA) is an essential omega-3 fatty acid. Plant sources include walnuts, flax or linseed, chia seeds and rapeseed oil.
Linoleic acid (LA) is an essential omega-6 fatty acid. Sources include sunflower, corn and several other vegetable oils, as well as nuts and seeds.
The body can convert these essential fatty acids into longer-chain products, but conversion of ALA to the long-chain omega-3 fatty acids EPA and DHA is limited[8]. Oily fish—including salmon, sardines, mackerel, herring and trout—is a direct food source. UK guidance is based on at least two portions of fish per week, one of which is oily[1, 2].
Food first, claims second
Omega-3 is often marketed for the brain, school concentration or sporting recovery. Those claims can make a normal nutrient sound like a shortcut. The responsible conclusion is more modest: omega-3 fatty acids have normal biological roles, and a varied diet can include food sources. A supplement should not be offered as a routine performance product for a child. Young-athlete reviews generally do not support supplements for performance without an identified clinical need and appropriate professional advice[6].
Food, Growth & Gymnastics
Fats in Ordinary Foods
Most foods contain a mixture
| Food or ingredient | What it can contribute | Keep in mind |
|---|---|---|
| Olive or rapeseed oil | Mainly unsaturated fat | Useful everyday cooking or dressing choices; quantity and cooking method still belong to the whole meal. |
| Nuts and seeds | Unsaturated fats, protein, fibre and micronutrients | Use age-appropriate forms and respect allergy guidance. |
| Oily fish | Long-chain omega-3 fats, protein and micronutrients | Variety matters; follow current fish guidance for children and pregnancy within the household. |
| Avocado | Mainly monounsaturated fat plus fibre and micronutrients | One possible source, not a required “superfood”. |
| Eggs | Protein, fat and several micronutrients | A mixed food; dietary cholesterol is not the same thing as blood cholesterol. |
| Milk, yoghurt and cheese | Protein, calcium and varying amounts and types of fat | Age, product and the rest of the diet matter; “full fat” or “low fat” alone cannot describe the whole meal. |
| Meat and poultry | Protein, iron and varying fat profiles | Cut and preparation change the mixture; leaner options can sit alongside other family foods. |
| Hummus, tahini and pulse dishes | Unsaturated fats may come from sesame or cooking oils; pulses add protein and fibre | A useful reminder that familiar composite dishes cross nutrient categories. |
The Eatwell Guide treats composite foods—sandwiches, casseroles, curries, pasta dishes and pizzas—as combinations of food groups[2]. This is closer to how London families actually eat than a diagram of isolated nutrients.
Food, Growth & Gymnastics
The London Reality
School, travel and evening classes
For many London families, the challenge is not knowing that varied food matters. It is fitting food into a day that moves between school gates, buses or trains, work, siblings and a fixed class time.
Route one: school meal, direct journey
The child eats lunch at school and travels straight to gymnastics. A familiar portable snack may bridge the gap until the evening meal. The snack does not need to contain every nutrient; it belongs to the wider day.
Route two: home briefly, then class
There is time for something more substantial, but appetite and comfort still matter. A sandwich, toast with egg, yoghurt with fruit, hummus with bread or another familiar household option can work. The exact choice depends on what the child ate earlier and what the family normally eats.
Route three: later family meal
Some children prefer a smaller food before class and eat the main meal afterwards. That meal may include rice, pasta, potatoes or bread; vegetables; beans, fish, eggs, meat or another protein food; and a cooking fat or sauce. It does not need to look like a sports-science diagram.
London’s cultural diversity means fats appear through olive oil, rapeseed oil, sunflower oil, ghee, tahini, nuts, seeds, fish, dairy foods, meat and many mixed dishes. Public-health guidance still matters, but respectful advice begins with the food a family actually cooks.
Food, Growth & Gymnastics
What Families Often Hear
Common misunderstandings
Food, Growth & Gymnastics
What Families May Notice
Attention without surveillance
It would be misleading to offer a short list of signs that a child “needs more fat”. Tiredness, appetite change, digestive symptoms, mood, growth and sporting performance can have many influences. Observation is useful; diagnosis requires appropriate assessment.
Notice the pattern
- Is the child frightened of foods described as fatty?
- Has the diet become increasingly narrow or rule-bound?
- Are allergy, sensory, cultural or medical restrictions making variety difficult?
- Is the school-to-gym gap repeatedly too long for the child’s appetite and comfort?
- Are there persistent symptoms, growth concerns or distress around eating?
Ask calm questions
Instead of “Have you eaten too much fat?”, try: “What food have you had since lunch?” “Are you hungry now?” “Would a familiar snack feel comfortable before class?” The purpose is to understand the day, not inspect the child’s body or grade the meal.
Seek appropriate help
Persistent symptoms, growth concerns, suspected allergy, significant restriction or distress around food should be discussed with a GP or appropriately qualified paediatric professional. A registered dietitian can provide individual nutrition assessment. Coaches can share relevant observations but should not diagnose or prescribe a therapeutic diet.
Food, Growth & Gymnastics
The Whole Diet, Not Fear of One Nutrient
Closing perspective
Dietary fat is essential, but no single fat, food or supplement carries a child’s development. A responsible pattern provides enough food, includes varied sources of unsaturated and essential fats, and treats foods higher in saturated fat with proportion rather than panic.
For gymnastics families, the practical work is often ordinary: breakfast before school, a lunch the child can eat, something workable between school and class, and an evening meal that fits family life. Growth comes before performance, and consistency matters more than perfection.
Key references
- Scientific Advisory Committee on Nutrition. (2025). SACN statement on expressing energy, fat and carbohydrate intakes and recommendations. UK Government. Official source
- Office for Health Improvement and Disparities. (2024). The Eatwell Guide. UK Government. Official source
- World Health Organization. (2023). Saturated fatty acid and trans-fatty acid intake for adults and children: WHO guideline. WHO source
- National Library of Medicine. (2026). Cholesterol. MedlinePlus Medical Encyclopedia. MedlinePlus source
- National Research Council (US) Committee on Diet and Health. (1989). Fat-soluble vitamins. In Diet and health: Implications for reducing chronic disease risk. National Academies Press. NCBI Bookshelf
- Hecht, C., Bank, N., Cook, B., & Mistovich, R. J. (2023). Nutritional recommendations for the young athlete: Current concept review. Journal of the Pediatric Orthopaedic Society of North America, 5(1), Article 599. DOI: 10.55275/JPOSNA-2023-599. PMID: 40433081. PubMed PMID: 40433081
- Scientific Advisory Committee on Nutrition. (2019). Saturated fats and health. Public Health England. Official source
- National Institutes of Health, Office of Dietary Supplements. (2024). Omega-3 fatty acids: Fact sheet for health professionals. NIH ODS source
- NHS. (n.d.). Preparing food safely for babies. NHS source