Facial features change over time, leading to the question of whether the face becomes more balanced with age. Scientific research shows that the differences between the left and right sides of the face do not diminish; instead, facial symmetry steadily decreases over the lifespan. Asymmetry means the two halves of the face are not perfect mirror images, a condition present in every human face. Quantitative studies confirm that facial asymmetry increases predictably as a person gets older.
What Facial Symmetry Means and Why It Matters
Facial symmetry is a measurable biological trait linked to perceived health and genetic quality, not merely an aesthetic concept. Evolutionary theory suggests that a symmetrical face signals developmental stability, reflecting an organism’s ability to navigate environmental and genetic stressors during growth.
High symmetry indicates robust development that resisted random perturbations, suggesting a strong underlying genetic makeup. This preference for symmetrical features is an evolutionarily driven trait influencing mate selection and social perception. While perfect bilateral symmetry is impossible, studies measure fluctuating asymmetry—small, random deviations from a mirror image. People perceive faces with lower fluctuating asymmetry as more attractive, trustworthy, and socially appealing.
The Developmental Peak: Symmetry During Growth and Early Adulthood
The trajectory of facial symmetry is not linear from birth but peaks after adolescent growth is complete. During childhood and puberty, the skeletal structure undergoes rapid, complex, and synchronized transformations. The two sides of the face grow at similar rates to maintain overall balance.
This phase of rapid, symmetrical growth is heavily influenced by hormones, such as testosterone, which shape the craniofacial complex. The growth spurt peaks around 14.4 years in boys and 11.5 years in girls. The face is generally at its most symmetrical point in the late teens to early twenties, once the skeletal framework has fully matured.
Skeletal maturity is attained between 13 and 15 years in females and 17 and 25 years in males. Once structural maturation is complete, the face enters a period of stability before age-related changes accelerate increasing asymmetry. This decrease marks the shift from a face defined by coordinated growth to one defined by accumulated wear and structural decline.
Mechanisms of Increasing Asymmetry Over the Lifespan
The increase in facial asymmetry after early adulthood results from differential changes in the underlying bone, soft tissues, and accumulated environmental damage. Researchers have quantified this shift using three-dimensional photogrammetry. Facial asymmetry increases by a predictable amount, approximately 0.06 millimeters, for each decade of life. This measurable change is most pronounced in the lower two-thirds of the face, from the eyebrows down to the chin.
Skeletal Changes
The craniofacial skeleton undergoes continuous remodeling, but this process is often asymmetrical, leading to structural imbalances. Differential bone resorption and deposition cause changes like jawbone recession and widening of the orbital sockets. For instance, osteoporosis around the eye socket can cause the eye to appear sunken, contributing to an uneven facial contour.
The maxilla and mandible, which form the middle and lower thirds of the face, continue to change dimension throughout life. This uneven remodeling means that one side of the face may lose support or shift position differently than the other. These subtle skeletal differences become more evident as the overlying soft tissue layer thins with age.
Soft Tissue Migration
Soft tissues, including fat, muscle, and skin, contribute significantly to age-related asymmetry through volume loss and gravitational effects. Facial fat pads, which provide smooth contours, begin to deflate and descend at different rates on each side. This volume loss unveils inherent asymmetries in the underlying bone structure that were previously masked by thicker fat.
Loss of skin elasticity, driven by the breakdown of collagen and elastin, causes the skin and muscle layers to sag unevenly. This differential descent of soft tissue, often called deflation and ptosis, rarely occurs equally on both halves of the face. The result is an uneven appearance in the cheeks, jowls, and lower eyelids, contributing to the overall decline in facial symmetry.
Environmental and Lifestyle Factors
External forces and daily habits compound natural biological processes, accelerating the increase in facial asymmetry. Uneven sun exposure, known as photoaging, is a primary environmental factor. This is especially true for individuals who spend significant time driving, which often exposes one side of the face to more ultraviolet radiation than the other. The resulting damage, such as deeper wrinkles and changes in skin texture, will be more prominent on the exposed side.
Habitual behaviors also contribute to uneven compression and migration of soft tissues:
- Consistently sleeping on one side of the face exerts chronic pressure.
- Uneven muscle use, such as preferring to chew food on only one side, can lead to differential development or atrophy of jaw muscles over decades.
- Dental issues, including tooth loss or misalignment, alter the position of the jaw, influencing the muscular and skeletal balance of the lower face.