Rumour: “Starting botulinum toxin (commonly called ‘botox’) at a young age prevents wrinkles” — What does the science say?

Short answer: it is not certain. Botulinum toxin temporarily reduces the movement of the muscles of facial expression; it is therefore thought that it may slow the formation of lines that deepen with repeated muscle movement. There are data supporting this, but they are limited: the most frequently cited study is based on a single pair of twins. There is no strong evidence showing that treatment started at a young age, when there is no noticeable line, makes a difference years later. The evidence for sun protection in delaying skin ageing is stronger.

Where does the rumour come from?

In recent years, botulinum toxin given to people in their 20s before wrinkles have formed has been offered under the name 'preventive' or 'prophylactic' treatment. On social media this approach is often presented as though it were a necessity: 'if you don’t start now, you’ll be too late'. There is real logic behind the idea; the problem is that this logic is presented as if it were a proven result.

What is the logic: dynamic lines and static lines

Some of the lines on the face arise from the movement of the muscles of facial expression. Lines that appear when you frown, raise your forehead or smile, and disappear when the face is at rest, are called dynamic lines. As the same movement is repeated over the years and the skin loses its elasticity, these lines can become visible even when the face is still; these are called static or established lines.

Botulinum toxin reduces the contraction of a muscle by temporarily blocking the signal travelling from the nerve to the muscle. The idea of preventive treatment arises from this: if the muscle contracts less, the skin folds less and the line may take longer to become established. This reasoning is biologically plausible. However, being plausible and being proven are not the same thing. How the substance works is described in detail in our article “Botulinum Toxin”.

What does the evidence say?

The most frequently cited data on this subject come from a case report comparing two sisters who are identical twins. One of the twins had regular treatment to the forehead and the area between the eyebrows for 13 years; the other had it only twice in the same period. In the twin who had regular treatment, no established lines at rest were seen in these areas; in the other, they were. The untreated areas of the face, meanwhile, aged similarly in the two sisters. The follow-up of the same twins in later years has also been published.

The second kind of data relates to repeated treatments. In a study in adults with lines at rest between the eyebrows, these lines were reported to lessen progressively in people treated three times at four-month intervals. This study measured the improvement of existing lines, not whether lines would form later in young people who have none.

A recent systematic review examining preventive use reached a similar conclusion: there are data suggesting that early treatment may delay lines becoming established by reducing muscle movement; however, the studies differ greatly from one another, and long-term effectiveness and safety have not yet been fully established.

Why is this evidence limited?

• A single pair of twins: a case report, however striking, is not enough to generalise from. The twins’ sun exposure, smoking, lifestyle and skin care habits may also have differed.
• Lack of a comparison group: there are no controlled studies that follow the same people for decades, treating some and not others.
• A different question: most of the studies were carried out in middle-aged people who have lines. Whether starting in one’s 20s, without lines, makes a difference in one’s 40s has not been measured directly.
• Conflicts of interest: some of the studies in this field were carried out with the support of product manufacturers or with the participation of manufacturers’ employees; the results should be read with this in mind.
• The effect is temporary: when treatment is stopped, muscle movement returns. Facial expression is not the only factor determining appearance years later; sun, genetics and structural changes in the skin also play a part.

For this reason, as we also note in our article “Skin Care and Medical Aesthetics in Your 20s: What Is Necessary, and What Is Not?”, although the view that treatment given before wrinkles form brings a long-term benefit is widespread, the evidence on this is limited.

The unknowns of early and frequent treatment

When weighing up preventive treatment, it is necessary to take into account not only the possible benefit but also the uncertainties. Someone who starts at a young age may find that, for the effect to continue, the treatment has to be repeated several times a year and for decades. There are very few studies following the consequences of cosmetic use over such a long period.

• The possibility of the effect diminishing: botulinum toxin is a protein, and the body can develop neutralising antibodies against it. In that case the treatment may become less effective over time or may have no effect. Expert consensus publications state that the true frequency of this in cosmetic use is not known and may be underestimated. The important point is this: if the same substance is needed later for a medical reason, for example in some muscle and nerve conditions, lack of effect could become a problem.
• An unnecessary procedure: having a procedure now for a line that would never cause a problem, or would appear years later, means taking on the possibility of side effects with every treatment while the benefit is uncertain. Side effects such as temporary drooping of the eyelid or eyebrow, asymmetry and headache can also occur at a young age.
• Facial expression: reducing muscle movement more than necessary in a young face can affect facial expression.
• Expectations and habit: aesthetic procedures that start at a young age can pave the way for ordinary changes in the face to be seen as a problem and for the number of procedures to increase.

The possible side effects and when to see a physician are described in our article “Side Effects after Botulinum Toxin: Drooping Eyelid, Asymmetry, Headache and What to Do”.

At what age should one start?

There is no agreed 'right starting age' for botulinum toxin for cosmetic purposes. The studies were carried out in adults, and the decision is based not on calendar age but on the person’s face. In some people lines start to become established early because of strong muscles of facial expression or a marked frowning habit; in others no noticeable line forms until later in life.

Having treatment for a line that is starting to be visible even at rest is not the same as having it when there is no line at all 'so that there won’t be one later'. The first is a treatment aimed at an existing change, with an effect that has been shown in studies. The second rests on an assumption whose benefit has not yet been clearly shown. No one can be told, on account of their age, 'you have left it too late' or 'you must start now'; it is sensible to be cautious about statements that apply this kind of pressure.

Stronger evidence: sun protection

If you want to delay skin ageing, the step with the most solid evidence is protecting yourself from the sun. In a randomised controlled trial in Australia with about 900 adults under the age of 55, no measurable increase in skin ageing was detected at the end of 4.5 years in those who used sunscreen every day; skin ageing in this group was found to be markedly less than in those who used sunscreen at their own discretion.

This is the kind of evidence we do not have for preventive botulinum toxin: a large number of participants, random allocation and follow-up lasting years. Sun protection concerns not only expression lines but also dark spots, deterioration in skin texture and the risk of skin cancer. Not smoking, enough sleep and simple care that does not irritate the skin are also part of this picture. A similar assessment for the 30s is given in our article “Skin Care and Medical Aesthetics in Your 30s: First Lines, Dark Spots and the Right Timing”.

If you are still considering it

• Make the decision not on the basis of general advice on social media but with a physician who examines your face in movement and at rest.
• Ask your physician, 'What happens if I don’t have this procedure?'; a physician who is able to say that a procedure is not necessary inspires confidence.
• Discuss how often the treatments will be repeated and how this plan will continue over the years; do not ask for the intervals to be kept shorter than necessary.
• Make sure the treatment is carried out only by a physician, in a healthcare facility and with a product of known origin.
• Be sure to mention pregnancy, breastfeeding, muscle and nerve conditions and the medicines you take.

Conclusion

That botulinum toxin given at a young age prevents later wrinkles is not a proven fact but a plausible assumption supported by limited data. There are observations that lines become less established in areas that are treated regularly; however, whether starting in a young person without lines makes a difference years later, and the consequences of use lasting decades, are not known. Sun protection, by contrast, is a measure that has been shown in a controlled study to delay skin ageing. The decision on a procedure should be made together with your physician after an examination, and without haste.