A unique long-term study has highlighted the effects of Botox on ageing by observing identical twin sisters over nearly two decades. Beginning at age 25, only one of the twins received regular Botox injections—two to three times a year—targeting her forehead, frown lines, and crow’s feet. Her sister remained untreated, serving as a natural control.
The study, led by Dr William Binder, began documenting the twins’ appearances in 2006, when they were 38. Early photographs already showed noticeable differences: the Botox-treated twin had visibly smoother skin and fewer wrinkles, particularly on the forehead and around the eyes. Over time, these distinctions became even more pronounced. By their mid-40s, the untreated twin exhibited a fuller face, wider jaw, and more prominent lines, while her sister retained a more youthful appearance with softer features.
Both women maintained healthy lifestyles, used sunscreen regularly, and avoided retinoids. However, environmental factors may have played a role—one lived in Munich, while the other resided in sun-drenched Los Angeles, potentially accelerating skin ageing due to higher UV exposure.
Dr Binder concluded that long-term Botox use not only reduces muscle contractions responsible for expression lines but may also subtly alter facial movement habits, preventing the deepening of wrinkles. Notably, no adverse effects were observed after over a decade of consistent treatment.
Further evidence of Botox’s impact came from Dr Bita Farrell, a specialist with over 20 years of experience. To demonstrate the treatment’s effects, she injected Botox into only one side of her own face, targeting muscles that pull the mouth downward and influence neck movement. Two weeks later, she documented a visible difference: the treated side was less mobile, resulting in a lifted appearance. This created a more defined jawline and fuller cheeks, while also smoothing nasolabial folds and marionette lines. Relaxation of the neck muscles also contributed to a firmer look.
Together, these cases illustrate the significant, long-term aesthetic benefits of Botox when used strategically and consistently. While ageing is inevitable, the study suggests that targeted interventions can meaningfully influence how those years appear on the face.
