Can your body still grow after 18?

October 2, 2025 •

4 min read

Genetics determine 60-80% of your height, but the question remains: Can your body still grow after 18? For most people, the answer is no, due to a key biological event that happens during puberty.

Quick Summary

The majority of individuals stop growing taller by the time they reach their late teens, typically between ages 18 and 20. This happens when the growth plates in the long bones of the body have fused completely, ceasing any further vertical bone growth.

Key Points

Growth Plate Fusion: The primary reason body height stops increasing is the fusion of growth plates in your bones, which occurs after puberty.
Age Range: Most females stop growing by 16 and most males stop by 19, though a small percentage may grow slightly into their early 20s.
Genetics Rule: Your maximum height is largely predetermined by your genetic makeup, with environmental factors playing a smaller role during development.
Medical Conditions: Continued growth into adulthood can be a sign of a rare medical condition and warrants a doctor's visit.
Posture and Perceived Height: Improving your posture through exercise and awareness can make you appear taller and is the most effective way for adults to affect their stature.
Adult Growth: While height from long bones ceases, other parts like cartilage in the nose and ears can continue to grow slowly throughout life.

Understanding the Biology of Height

To understand whether you can grow after 18, it's crucial to first grasp how human height is determined. Our height is primarily influenced by the lengthening of long bones in our legs and arms. This process is orchestrated by areas of specialized cartilage known as growth plates, or epiphyseal plates, located at the ends of these bones. During childhood and adolescence, these growth plates are active, producing new bone cells that elongate the bones. Hormonal changes during puberty, including the increased production of sex hormones like estrogen and testosterone, accelerate this process, leading to the rapid height increase often called a 'growth spurt'.

The Critical Factor: Growth Plate Closure

For nearly everyone, this growth process comes to an end when puberty concludes. As puberty progresses, rising hormone levels signal the growth plates to harden and fuse with the rest of the bone, a process called epiphyseal fusion. Once fused, the growth plates are inactive, and no further increase in the length of the long bones can occur. This typically happens for girls between ages 14 and 16, and for boys between ages 16 and 19. While some individuals may experience a final, minor height increase into their early twenties, significant growth is extremely rare once this fusion is complete. This is the main reason why the notion that a person can significantly increase their height as an adult is a myth.

The Late Bloomer Exception

In some rare instances, a person might be a "late bloomer," experiencing delayed puberty. For these individuals, their growth plates might remain open a little longer, potentially allowing for some additional growth into their early twenties. However, even these late growth spurts are usually minor and conclude once the growth plates fully fuse. Continued, unexplained growth past the early twenties is considered abnormal and should be evaluated by a healthcare provider, as it could indicate a medical condition.

What About Other Types of Growth?

While an adult's long bones cannot grow any longer, the body is not completely static after 18. Some parts of the body continue to grow, change, or develop in other ways. For instance, the cartilage in your nose and ears continues to grow throughout your life, albeit very slowly. Furthermore, adults can build muscle mass through proper diet and exercise, which contributes to overall physical development and strength.

Muscle Mass: Muscle growth can continue well into adulthood, especially with a focused fitness regimen.
Cartilage: Soft tissues like the cartilage in the ears and nose experience a slow, steady growth over a lifetime.
Spinal Discs: The discs between your vertebrae compress throughout the day, leading to a slight height reduction that is regained during sleep. Improved posture can affect how you present your height but doesn't change bone length.

Maximizing Perceived Height as an Adult

For adults who are unhappy with their stature, focusing on improving posture can make a noticeable difference. Poor posture, such as slouching, can subtract a few inches from your perceived height. Strengthening your core and back muscles through exercise, along with being mindful of how you stand and sit, can help you appear taller and more confident.

Maximizing Growth Potential as a Teen

For adolescents who are still in their growth phase, a few factors can help ensure they reach their maximum genetic potential:

Good Nutrition: A diet rich in protein, calcium, and Vitamin D is essential for bone health and growth.
Adequate Sleep: The body releases growth hormones during sleep, making sufficient rest crucial for development.
Regular Exercise: Physical activity helps strengthen bones and promotes the release of growth hormones.

Can Diet or Exercise Increase Height After 18?

While a healthy lifestyle is vital for overall health, it cannot reverse the process of growth plate fusion once it's complete. Dietary supplements and specific exercises marketed to increase adult height are not scientifically supported. These claims often misinterpret the temporary decompression of spinal discs with actual bone growth. Maintaining a healthy diet and exercise routine as an adult is still important for preventing age-related height loss and strengthening your body.


Aspect	Maximizing Potential (Teens)	Increasing Height (Adults)
Genetics	Influences 60-80% of final height	Predominantly determines final height
Nutrition	Crucial for reaching maximum potential	Important for preventing age-related bone loss
Sleep	Essential for growth hormone release	Key for overall health, but not height
Exercise	Promotes healthy bone and muscle growth	Can improve posture and prevent height loss
Growth Plates	Active and responsive to hormones	Fused and inactive, no further growth
Hormone Therapy	Can be used under medical supervision for abnormal growth	Ineffective for increasing height once growth plates are closed

In Conclusion

While the prospect of increasing height after 18 is unlikely for the vast majority of people, understanding the science behind growth can offer clarity and set realistic expectations. Once the growth plates have fused, the potential for increasing height from your long bones is gone. Focusing on good posture, maintaining a healthy lifestyle to protect bone density, and appreciating that height is just one aspect of your overall health and well-being are the best approaches for adults. For more information on growth and development, consider consulting reliable health sources like the Cleveland Clinic's health library.

Frequently Asked Questions

Yes, but it is rare. Some individuals, known as 'late bloomers,' may have a final growth spurt that extends into their early 20s. However, this growth is typically minor and stops once their growth plates have fused, which is usually not long after the average age.

No. Once the growth plates at the ends of your long bones have fused and hardened into solid bone, they cannot be reopened or reactivated. This means the process of increasing height from these bones is permanently over.

While proper nutrition is essential for overall health and maximizing your height potential during your growing years, it cannot cause an increase in height once your growth plates have closed. As an adult, it helps prevent age-related height loss by supporting bone density.

Genetics are the biggest factor determining your final height, accounting for about 60-80% of your stature. This is why tall parents often have tall children, and vice versa. Environmental factors, like nutrition and health, play a role but primarily during childhood and adolescence.

No. Exercises like stretching or weightlifting cannot make your bones grow longer after puberty. While they can improve posture, which can make you appear taller, they do not increase your actual biological height. In fact, spinal compression from daily activities can cause slight height fluctuations.

The most definitive way to know if your growth plates are still open is through an X-ray, as they appear as distinct lines of cartilage. Other less scientific signs during puberty include changes in clothing size (e.g., pants becoming too short) and general signs of pubertal development, though these are much less reliable after age 18.

In most cases, it may simply be a case of delayed puberty. However, in very rare instances, excessive and prolonged growth can be a symptom of a hormonal disorder like acromegaly. It's always best to consult a healthcare provider for a proper evaluation if you are concerned about your growth.