Supplements and energy drinks: does a 14-year-old actually need them?

Almost never. The American Academy of Pediatrics report concludes that in young athletes these substances do not produce significant gains over those seen with the onset of puberty and adherence to an appropriate nutrition and training programme (LaBotz and Griesemer, 2016). And 14.8% of 634 supplements analysed across 13 countries contained anabolic steroids not declared on the label (Geyer et al., 2004).

On the shelf there are tubs labelled «recovery», cans labelled «energy» and sachets with names that sound like molecules. In the changing room there is a teammate who drinks one before every match. In between there is a fourteen-year-old girl nobody has told three things: that those products are not the same thing, that the evidence behind them was collected almost entirely on adults, and that a measurable share of those tubs contains something the label does not mention. What the data actually say — and what is missing from the plate instead.

On the shelf of the sports shop there are tubs labelled «recovery», cans labelled «energy» and sachets with names that sound like molecules. In the changing room there is a teammate who drinks one before every match and says it «gives her a lift». In between there is a fourteen-year-old girl nobody has told three things.

The first is that those products are not the same thing as each other. The second is that the evidence behind the few that work was collected almost entirely in adult athletes. The third is that a measurable share of those tubs contains something the label does not mention.

In brief

  • In most young athletes, substances that promise performance do not produce significant gains over those that arrive with puberty and with appropriate training and nutrition (LaBotz and Griesemer, 2016; report of a paediatric scientific society).
  • Of 634 non-hormonal supplements purchased in 13 countries from 215 suppliers, 14.8% contained anabolic androgenic steroids not declared on the label (Geyer et al., 2004; samples collected in 2000-2001). A review of 23 studies up to 2017 reports contamination rates between 12% and 58% (Martínez-Sanz et al., 2017).
  • For children and adolescents, EFSA states that the available information is insufficient to derive a safe caffeine intake; the adult value of 3 mg/kg may serve as a basis (EFSA, 2015). For non-pregnant adults: 200 mg as a single dose, 400 mg a day habitually.
  • Caffeine and the other stimulant substances in energy drinks have no place in the diet of children and adolescents, according to the American Academy of Pediatrics clinical report (Schneider and Benjamin, 2011).
  • Recommendations for safe caffeine consumption in paediatric age are based on decades-old data collected exclusively in adults (Temple, 2019).
  • In 187 Canadian athletes aged 11-18, girls aged 14-18 had median intakes below the recommended allowance for iron (91%), folate (89%) and calcium (84%), with vitamin D below the RDA in every group (Parnell et al., 2016; cross-sectional study, single 24-hour recall).
  • The IOC consensus statement recognises good evidence of benefit for only a few products — caffeine, creatine, specific buffering agents, nitrate — but in the adult elite athlete (Maughan et al., 2018).

Sports drink, energy drink, supplement: what is the difference?

They are three different categories, and confusing them is the first mistake. The American Academy of Pediatrics clinical report devoted to these products explicitly asks that «sports drink» and «energy drink» not be used as synonyms (Schneider and Benjamin, 2011).

Product What it contains What it is for
Sports drink Water, carbohydrate, electrolytes Rehydrating and supplying sugars during long or intense effort
Energy drink Caffeine and other stimulants, often a lot of sugar Nothing that concerns an adolescent athlete's performance
Dietary supplement Nutrients or compounds taken in addition to the usual diet Correcting a documented deficiency, or — in a few cases — adding a performance margin

The distinction is not lexical pedantry. The same report adds something that is rarely said about the one considered «good» of the two: frequent or excessive intake of caloric sports drinks can substantially increase the risk of overweight and obesity in children and adolescents. A sports drink during a long match on a hot day is a reasonable choice; the same sports drink in a classroom is sugar.

Does a supplement actually make you faster at 14?

Almost always no, and the reason is that something more powerful is already under way at that age. The American Academy of Pediatrics report on performance-enhancing substances puts the decisive sentence in its conclusion: the physical maturation and endogenous hormone production that occur in adolescence are associated with large improvements in strength and athletic performance, and for most young athletes the use of these substances does not produce significant gains over those seen with the onset of puberty and adherence to an appropriate nutrition and training programme (LaBotz and Griesemer, 2016).

Put another way: the comparison is not between «supplement» and «nothing». It is between «supplement» and «a growth spurt plus strength training done properly plus enough to eat». In that comparison the tub loses, and loses badly.

Then there is the misunderstanding about what the International Olympic Committee consensus statement actually says. That document recognises good evidence of benefit for a narrow group of products — caffeine, creatine, specific buffering agents and nitrate — but it is, from the title onwards, a document about the high-performance elite athlete (Maughan et al., 2018). Adult population, a performance context where margins of fractions of a second are being hunted, professional supervision taken for granted. Transferring those conclusions to a fourteen-year-old in a youth team means changing three variables out of three.

How real is the risk of taking something the label does not mention?

Real enough to have been counted. Between October 2000 and November 2001, 634 non-hormonal supplements were purchased in 13 countries from 215 different suppliers, almost all of them in physical shops. Analysed by gas chromatography-mass spectrometry, 94 samples — 14.8% — contained anabolic androgenic steroids not declared on the label, mostly prohormones of testosterone and nandrolone (Geyer et al., 2004).

Three details of that study are worth reporting in full, because they change the reading:

The samples are twenty-five years old and that should be said. But the problem did not close in 2001: a review that examined 23 studies published up to September 2017 reports contamination rates between 12% and 58%, depending on product category and study (Martínez-Sanz et al., 2017). And the 2016 paediatric report lists «high rates of product contamination» among the three main concerns about legally available supplements, alongside the correlation with future use of anabolic androgenic steroids (LaBotz and Griesemer, 2016).

For a fourteen-year-old athlete the practical consequence is almost never a doping control. It is that nobody — not her, not her parents, not her coach — knows what is inside that tub.

Does caffeine work in 14-year-old girls too?

In adult women yes, with precise numbers; in adolescents we do not know with the same confidence. The International Society of Sports Nutrition position stand reports that caffeine consistently improves performance at doses of 3-6 mg per kg of body weight, with small to moderate benefits for muscular endurance, movement velocity, strength, sprinting and jumping, and the most consistent benefits for aerobic endurance; the minimal effective dose may be as low as 2 mg/kg, while very high doses such as 9 mg/kg come with a high incidence of side effects without adding benefit (Guest et al., 2021).

That literature, however, is built overwhelmingly on adult participants. And the review devoted to caffeine in paediatric age states it in the first line of its objective: recommendations for safe consumption in children and adolescents are based on decades-old data collected exclusively in adults (Temple, 2019).

There is also a side effect that weighs more in adolescents than in adults, and which the position stand itself lists among individual responses: sleep. In a fourteen-year-old athlete, who has a sleep need and a circadian rhythm different from an adult's, a dose of caffeine taken in the afternoon to «get through» a 7 pm session can cost more than it returns.

How much caffeine is too much under 18?

The honest answer is that a threshold measured in adolescents does not exist. The EFSA scientific opinion on the safety of caffeine says so explicitly: for children and adolescents the available information is insufficient to derive a safe caffeine intake. The Panel adds that the value derived for acute consumption in adults — 3 mg per kg of body weight — may serve as a basis for deriving single doses and daily intakes of no concern for these population subgroups (EFSA, 2015).

For non-pregnant adults the same opinion indicates that single doses up to 200 mg (about 3 mg/kg for a 70 kg adult) and habitual consumption up to 400 mg a day do not give rise to safety concerns.

Translated for a 50 kg athlete: 3 mg/kg works out to 150 mg a day. It is a useful figure for orientation, and it should be used knowing what it is — an extrapolation from adult data, not a safety threshold measured in fourteen-year-old girls. At the upper end the paediatric review is blunter: intakes above 400 mg can cause physiological, psychological and behavioural harm, particularly in some subgroups, such as those with psychiatric or cardiac conditions (Temple, 2019).

Do energy drinks have a place in youth sport?

According to the American Academy of Pediatrics clinical report, no — and the wording leaves no room. After a review of the literature, the authors conclude that the caffeine and other stimulant substances contained in energy drinks have no place in the diet of children and adolescents (Schneider and Benjamin, 2011).

It should be read as what it is: the position of a paediatric scientific society, built on the available literature, not the outcome of an experimental study. It is synthesis and recommendation, not a measurement. But it is also the document that same society points to for screening, suggesting that sports and energy drink consumption be asked about during the annual physical — that is, treating it as ordinary clinical information rather than a taboo.

What is actually missing from a 14-year-old athlete's plate?

Micronutrients, almost always. And they are found in food. This is the constructive half of the discussion, and also the one with the most useful figure.

In a study of 187 Canadian athletes aged 11-18, assessed with an online 24-hour dietary recall and a supplement questionnaire, girls aged 14-18 showed median intakes below the recommended dietary allowance for three nutrients: iron at 91% of the RDA, folate at 89%, calcium at 84%. Vitamin D was below the RDA and potassium below the adequate intake in every athlete group, boys included (Parnell et al., 2016).

The authors' conclusion is the sentence worth taking away: with the exceptions of vitamin D and carbohydrate during long exercise sessions, supplementation is generally unnecessary — what is needed is a focus on food sources of calcium, vitamin D, potassium, iron and folate.

Two caveats before using those numbers. The study is cross-sectional, in a Canadian population, and based on a single 24-hour recall per participant: it says where to look in a group, not how much any individual athlete is short. And the list of at-risk nutrients is not random: they are the same ones that come back when talking about iron and fatigue in adolescent athletes, about bone health and stress fractures and about low energy availability. The problem, when there is one, is almost always that too little or too narrow a range of food is being eaten — not that a powder is missing.

When does a supplement make sense, and who decides?

When there is a documented deficiency, and a healthcare professional decides after an assessment. The IOC consensus statement is explicit on both points: a complete nutritional assessment should be undertaken before decisions regarding supplement use are made, and expert professional opinion and assistance are strongly advised before an athlete embarks on supplement use (Maughan et al., 2018).

The most frequent case in adolescent female athletes is iron, and that case shows exactly why the rule matters: iron deficiency is measured with a blood test, it is not inferred from tiredness, and supplementing without having measured it means at best spending money and at worst masking something else. The same holds for vitamin D, which was below the RDA in every group in the Canadian study (Parnell et al., 2016) and which remains a clinical decision.

What does not decide whether a fourteen-year-old takes a supplement: the coach, the teammate, the shop assistant, a video.

What can a club actually do?

Three things, none of which requires clinical expertise.

Ask, without lecturing. The 2011 paediatric report proposes including sports and energy drink consumption among the questions at the annual physical (Schneider and Benjamin, 2011). A club can do the same thing more simply: knowing what athletes drink before matches is information, not an accusation.

Take the product out of the context that makes it look normal. If cans circulate on the bench, the implicit message is that they are needed. No rule is required: it is enough that water and real food are the thing that is available.

Do not prescribe. A coach who recommends a supplement is making a health decision for a minor without either the assessment or the responsibility that decision requires (Maughan et al., 2018). The fact that the product is legally on sale changes nothing here: 14.8% of the legally available products analysed by Geyer contained undeclared steroids (Geyer et al., 2004).

And a note on language, because it recurs on this site: «you need a lift», said to a fourteen-year-old who is simply tired, is a diagnosis dressed as encouragement. The words used to name the state of a growing body steer what that body then goes out to buy.

When should you see a professional?

When there is a symptom to explain, not a product to choose. Tiredness that does not lift with rest, performance dropping without a training-load reason, periods thinning out or stopping, unusual breathlessness, palpitations or sleep problems in an athlete who habitually drinks caffeinated beverages: all of these are reasons to talk to a doctor, and none of them is a reason to add a supplement.

The opposite case matters too, and is seen less often: an athlete who has already started taking something on her own initiative. Asking her what she is taking, without reacting, is the precondition for her being able to say it.

Sources

This article is for information only and does not constitute medical advice, a clinical assessment or nutritional counselling. The doses cited come from the sources indicated and are not a recommendation: for children and adolescents, EFSA declares the data insufficient to derive a safe caffeine intake. Persistent tiredness, a drop in performance without a training-load cause, changes to the menstrual cycle, palpitations or sleep problems should be assessed by a healthcare professional, as should any decision about supplement use in a minor.

What is the difference between a sports drink and an energy drink?

They are two different products, and the American Academy of Pediatrics clinical report explicitly asks that the two terms not be used interchangeably (Schneider and Benjamin, 2011). A sports drink contains water, carbohydrate and electrolytes, and is designed to rehydrate and supply sugars during long or intense effort. An energy drink contains caffeine and other stimulant substances, often alongside a great deal of sugar. The same report adds that frequent or excessive intake of caloric sports drinks can substantially increase the risk of overweight and obesity in children and adolescents: not even the «harmless» one of the two is meant to be drunk at school or in front of the television.

Does a supplement make a 14-year-old girl run faster?

In the vast majority of cases, no. The American Academy of Pediatrics report on performance-enhancing substances concludes that for most young athletes their use does not produce significant gains over those seen with the onset of puberty and adherence to an appropriate nutrition and training programme (LaBotz and Griesemer, 2016). The IOC consensus statement on supplements recognises good evidence of benefit for only a few products — caffeine, creatine, specific buffering agents and nitrate — but it does so for the high-performance athlete, that is, in an adult population and in a performance context that is not a fourteen-year-old's (Maughan et al., 2018).

How real is the risk of supplement contamination?

It has been measured, and it is high. In the landmark international study, 634 non-hormonal supplements were purchased in 13 countries from 215 different suppliers: 94 of them, or 14.8%, contained anabolic androgenic steroids not declared on the label (Geyer et al., 2004). The share rose to 21.1% among products from companies that also sell prohormones and stayed at 9.6% among those that do not. The study sampled the market of 2000-2001, but the problem did not end there: a review of 23 studies published up to 2017 reports contamination rates between 12% and 58% (Martínez-Sanz et al., 2017).

How much caffeine is safe for an adolescent?

There is no measured answer, and that matters. The EFSA scientific opinion states that for children and adolescents the available information is insufficient to derive a safe caffeine intake, and proposes using the adult-derived value, 3 mg per kg of body weight, as a basis (EFSA, 2015). For a 50 kg athlete that works out to 150 mg a day — but it is an extrapolation from adult data, not a threshold measured in fourteen-year-old girls. For non-pregnant adults the opinion indicates single doses up to 200 mg and habitual intakes up to 400 mg a day as giving rise to no safety concerns.

Are energy drinks appropriate for athletes aged 13-17?

The American Academy of Pediatrics clinical report is blunt: the caffeine and other stimulant substances contained in energy drinks have no place in the diet of children and adolescents (Schneider and Benjamin, 2011). It is the position of a paediatric scientific society, not the outcome of an experimental study, and it should be read as what it is: a precautionary recommendation built on the available literature. A later review of caffeine in paediatric age adds that intakes above 400 mg can cause physiological, psychological and behavioural harm, particularly in those with psychiatric or cardiac conditions (Temple, 2019).

Does caffeine improve performance in adolescent athletes too?

In adolescents we do not know with the same confidence. The International Society of Sports Nutrition position stand reports that caffeine improves performance at doses of 3-6 mg per kg of body weight, with small to moderate benefits for muscular endurance, movement velocity, strength, sprinting and jumping, and that very high doses such as 9 mg/kg come with a high incidence of side effects without adding benefit (Guest et al., 2021). That literature, however, is built overwhelmingly on adults. A review dedicated to paediatric age says as much explicitly: recommendations for safe consumption in children and adolescents are based on decades-old data collected exclusively in adults (Temple, 2019).

What is actually missing from an adolescent athlete's diet?

Micronutrients found in food, not performance in powder form. In a study of 187 Canadian athletes aged 11-18, girls aged 14-18 had median intakes below the recommended dietary allowance for iron (91% of the RDA), folate (89%) and calcium (84%), while vitamin D was below the RDA in every athlete group and potassium below the adequate intake (Parnell et al., 2016). The authors' conclusion is the most useful part: with the exceptions of vitamin D and carbohydrate during long exercise sessions, supplementation is generally unnecessary. The study is cross-sectional, in a Canadian population and based on a single 24-hour recall: it shows where to look, not how much any individual athlete is short.

Who should decide whether an athlete takes a supplement?

A healthcare professional, after an assessment — not the coach, the teammate or the shop. The IOC consensus statement indicates that a complete nutritional assessment should be undertaken before any decision about supplement use, and strongly advises expert professional opinion and assistance before an athlete embarks on supplement use (Maughan et al., 2018). The reason is not procedural: a supplement makes sense when there is a documented deficiency to correct — iron being the most frequent case in adolescent female athletes — and in that case the decision requires a test, not a hunch.

Why do athletes use supplements more than you would expect?

Because the reasons are not only sporting ones. The 2016 paediatric report observes that more recent data show these substances are often used for appearance-related reasons as well, not only for performance (LaBotz and Griesemer, 2016). On the quantities, honesty requires a caveat: the largest meta-analysis, 159 studies, reports that elite athletes use supplements far more than non-elite ones and that iron use is more common among women, but also declares generally low methodological quality — on average 43% of the available points on the rating scale (Knapik et al., 2016). A more recent review confirms that the lack of homogeneous definitions makes prevalence figures hard to compare across studies (Daher et al., 2022). There is, today, no reliable figure for Italian girls aged 13-17.