A Broth + Co guide to building strong bones during childhood, adolescence and early adulthood, and supporting your skeleton throughout life.

When people think about bone health, they often picture later adulthood: osteoporosis, fractures, calcium supplements and healthy ageing. But one of the most important periods for lifelong bone health happens much earlier.

Your skeleton spends childhood, adolescence and early adulthood building something scientists call peak bone mass. The name sounds technical, but the idea is simple: peak bone mass is your body's bone savings account.

During the growing years, your skeleton is making deposits. New bone is formed faster than old bone is removed. Bones become larger, stronger and denser. Eventually, most people reach the highest amount of bone tissue they are likely to achieve. That milestone is called peak bone mass.

 

Your Bones Have a Once-in-a-Lifetime Opportunity

Think of building a house. Before you think about paint colours or furniture, you need strong foundations. The stronger the foundation, the better the house can tolerate years of weather, movement and wear.

Your skeleton follows a similar principle. During the early decades of life, the body is investing in the framework that will carry you for decades. This does not mean bones stop changing afterwards. They continue to remodel throughout life. But a higher peak bone mass gives the skeleton a stronger starting point.

This is the 'I never knew that' moment for many people: bone health is not only something to think about later. It is something the body is quietly building long before most people are paying attention.

For the broader biology of living bone, read Bone Isn't Solid—It's Living Tissue and Bone Biology Explained: How Your Bones Continuously Renew Themselves.

Most Bone Is Built Earlier Than You Think

Researchers commonly estimate that around 90% of peak bone mass is achieved by approximately 18 years of age, with much of the remaining bone accumulated during the 20s before peak bone mass is generally reached. Exact timing varies between individuals, but the principle is clear: the growing years matter.

The teenage years and young adulthood represent an extraordinary window of opportunity. During this period, bones are responding to growth, hormones, movement, nutrition, sleep and everyday habits. The skeleton is not simply getting bigger. It is becoming stronger, denser and better prepared for adult life.

This does not mean anyone should panic if their teens or 20s were not perfect. Biology is not that unforgiving. But it does mean we should take childhood and young adult nutrition seriously, especially for active kids, teenagers, young women, athletes and anyone with high training demands.

Why Your 20s Still Matter

The title of this article mentions your 20s because this decade is often treated as nutritionally invincible. Many young adults are studying, working, training, travelling, socialising, moving out of home or learning to cook for themselves. Bone health is rarely top of mind.

Yet the 20s can still be part of the peak bone mass story. The skeleton is no longer growing at the same pace as childhood or puberty, but it may still be consolidating bone before peak bone mass is fully reached. This makes the basics especially valuable: resistance training, weight-bearing movement, regular meals, adequate protein, calcium-rich foods, vitamin D, enough total energy and sleep.

This is also a time when habits become independent. A young adult who learns to cook, lift well, eat enough and recover properly is not only supporting today's performance. They are building routines that can follow them into later adulthood.

 

Peak Bone Mass Does Not Mean Bones Stop Changing

The term peak bone mass can make the skeleton sound fixed, as though bones reach a final state and then simply stay there. That is not how bone works.

Bones remain living tissues throughout life. Specialised bone cells continually remove older bone and replace it with new bone through a process called bone remodelling. This helps repair microscopic wear, respond to movement and maintain bone quality.

After peak bone mass is reached, the body generally shifts from mostly building bone to maintaining and renewing the bone already built. Your skeleton never becomes inactive. It simply enters a new phase of its lifelong work.

For more on this, see Why Your Skeleton Is Constantly Changing and Bone Remodelling Explained: How Your Skeleton Constantly Renews Itself.

What Determines Peak Bone Mass?

No two people build exactly the same skeleton. Some people are naturally taller, broader or more lightly built. Genetics influence bone size, shape, density and growth patterns. Family history matters.

But genes are not the whole story. Think of genetics as the blueprint. Lifestyle helps determine how fully that blueprint is realised. Movement, nutrition, hormones, sleep and healthy routines all influence the environment in which bones develop.

This is encouraging because it gives families, teenagers and young adults practical levers to support bone health without turning nutrition into a fear-based checklist.

Hormones Help Coordinate Growth

Growth during childhood and adolescence is carefully coordinated by hormones. These natural chemical messengers help regulate growth, puberty and the normal development of bone tissue.

During adolescence, periods of rapid growth place greater demands on the skeleton as bones lengthen and become stronger. This is one reason the teenage years are so important. The body is not simply adding height. It is coordinating bones, muscles, connective tissues, hormones and energy needs all at once.

This is also why under-fuelling, poor sleep, excessive training loads or restrictive eating can be a concern during adolescence. A growing body needs resources, not just discipline.

 

Movement Helps Bones Grow Stronger

Children were not designed to sit still all day. Running, jumping, skipping, climbing, dancing, throwing, balancing and playing sport all expose the skeleton to different loading patterns.

Every jump sends forces through the legs. Every landing challenges the hips and spine. Every climb asks muscles and bones to work together. These are not just games. They are biological messages.

Scientists call the conversion of physical force into biological signals mechanotransduction. The simple version is this: movement becomes information. Bones use that information as part of their normal growth and remodelling processes.

For more detail, read Mechanotransduction Explained: How Movement Becomes a Biological Signal and Why Exercise Builds Stronger Bones: The Science of Bone Loading.

 

Sport Helps, But Variety Matters

Many sports naturally provide useful loading for growing bones. Basketball, soccer, tennis, dance, martial arts, gymnastics and athletics all include some combination of running, jumping, landing, direction changes and muscle contractions.

But the goal is not to push every child into elite sport. Bone-friendly movement can be playful and varied. Climbing at the park, skipping, dancing in the lounge room, backyard games, walking to school, supervised strength work and weekend outdoor activity all contribute different movement signals.

Variety is helpful because the skeleton does not experience life in straight lines. It responds to load from different directions, intensities and rhythms. A broad movement diet helps children build confidence, coordination and capacity, not just fitness.

Nutrition Provides the Building Materials

Movement provides the stimulus, but bones also need the raw materials to grow. During the years when peak bone mass is developing, the body requires enough energy and nutrients to support growth, hormones, brain development, sport, school, recovery and everyday life.

Protein supplies amino acids used to produce Type I collagen, the structural framework of bone. Calcium and phosphorus help strengthen that framework through mineralisation. Vitamin D supports normal calcium absorption. Vitamin C contributes to normal collagen formation. Magnesium and vitamin K also contribute to normal bone health.

This is why strong bones need more than one nutrient. Calcium matters, but bone is not made from calcium alone. It is a living tissue built from collagen, minerals, cells, signals and repeated movement.

Useful next reads include Why Strong Bones Need More Than Calcium, Why Protein Matters for Healthy Bones, Collagen Is More Than Skin: Understanding the Body's Most Abundant Protein and Collagen Amino Acids Explained: Glycine, Proline & Hydroxyproline.

Calcium Is Important, But It Is Not the Whole Story

Calcium has dominated the bone health conversation for decades, and for good reason: it is an essential mineral in bone. But focusing only on calcium can make people miss the rest of the biology.

Bone is a composite material. The collagen framework gives bone a degree of flexibility and resilience. Minerals such as calcium and phosphorus give bone hardness. Movement tells bone where strength is needed. Protein supplies amino acids. Vitamin D helps the body absorb calcium. Vitamin C supports normal collagen formation.

A useful analogy is reinforced concrete. The steel framework and concrete each matter, but neither tells the whole story alone. Bone is similar: structure, minerals, cells and signals all work together.

Why Teens and Young Athletes Need Enough Energy

The growing years are nutritionally demanding. Teenagers may be growing, training, studying, concentrating, socialising and recovering all at once. Active teens need enough energy to support both activity and normal physiological needs.

If energy intake does not match demand, the body has fewer resources available for its normal growth, hormone and maintenance processes. This is especially relevant for young athletes with high training loads, busy schedules or pressure around body composition.

Active girls and young women deserve particular attention because adolescence and early adulthood are key years for building the bone they will rely on throughout life. Researchers have recognised that low energy availability can affect normal hormonal function and bone remodelling. Supporting young athletes means looking beyond training performance and making sure food, rest and recovery are adequate too.

For a deeper article on this group, read Why Female Athletes Need to Think About Bone Health Earlier.

Signs the Routine May Need More Support

This article is not about diagnosing health problems, but it is worth noticing when a young person's routine may not be supporting their training or growth well. Persistent fatigue, frequent injuries, poor recovery, skipped meals, fear of food, irregular menstrual cycles in girls and young women, or pressure to stay very lean are all reasons to seek qualified support.

The helpful message is not to stop moving. It is to match movement with enough nourishment and recovery. Training is a stimulus. Food and rest help the body respond to that stimulus.

 

Bone Health Starts Earlier Than Most People Think

Peak bone mass is not only a 20s story. It starts with childhood growth, family meals, active play and the habits that help children feel confident around food and movement.

Children need development and growth support, not adult diet culture. That means enough food, regular meals, protein, dairy or other calcium-rich foods where appropriate, fruits, vegetables, outdoor activity, play and a positive relationship with movement.

The foundations also begin before childhood. Maternal nutrition, early feeding and the first years of life all contribute to growth and development. The First 1,000 Days: Why Protein Matters for Mum, Baby & Healthy Development., Children's Nutrition: Building Healthy Eating Habits for Life and Nutrition Across the Lifespan: From Childhood to Healthy Ageing connect this bigger lifecycle story.

What Parents Can Do Without Overcomplicating It

Parents do not need to turn bone health into another stressful project. The most powerful foundations are ordinary: regular meals, enough food, protein at meals, calcium-rich options, colourful plants, outdoor play, sport or active hobbies, and sleep routines that give growing bodies time to recover.

It also helps to talk about bodies in terms of capability rather than appearance. Bones, muscles and connective tissues are there to help children run, climb, learn, play, dance, carry, grow and feel confident in their bodies. That is a far healthier frame than making nutrition feel like control.

What Happens After Peak Bone Mass?

Reaching peak bone mass is not the end of bone health. It is the beginning of the maintenance phase. Your skeleton has spent years building its foundation; now it continues renewing and protecting that foundation through bone remodelling.

Your habits still matter. Every walk, hike, resistance session, game of tennis, afternoon in the garden, protein-containing meal and good night's sleep contributes to the environment your skeleton lives in.

You cannot go back and rebuild childhood. But you can continue supporting living bone today. That message matters because it keeps bone health positive rather than fatalistic.

For adulthood and ageing context, see Protein Throughout Life: Why Your Protein Needs Change With Age, High-Protein Foods: The Foundation of Muscle, Healthy Ageing & Recovery Nutrition and The 5 Pillars of Healthy Ageing: Everyday Habits That Support a Longer, Healthier Life.

Different Goal, Same Living Tissue

Before peak bone mass, the goal is to build. After peak bone mass, the goal is to maintain, renew and protect. The underlying message is the same: bone is alive and responsive.

An adult who starts strength training in their 40s, 50s or 60s is still sending useful signals to the skeleton and muscles. An older adult who improves protein intake, balance, walking confidence and resistance training is still supporting the body they have today. Peak bone mass matters, but it is not the only chapter.

Where Bone Broth Fits

Bone broth is not a shortcut to healthy bones, and it does not replace regular movement, calcium-rich foods, vitamin D, balanced meals or appropriate healthcare advice. It can, however, be a practical way to contribute protein and collagen-derived amino acids as part of a varied food-first routine.

For growing teenagers, active adults or older adults, the most useful approach is the same: use bone broth as one food within a broader pattern that includes quality protein sources, vegetables, fruit, calcium-rich foods where suitable, enough total energy, hydration and regular movement.

To understand the protein and amino acid side, read Bone Broth Benefits: The Complete Guide to Gut Health, Protein, Recovery & Healthy Ageing and The Amino Acids in Bone Broth: What They Are and Why They Matter.

A Simple Bone-Building Framework

This framework is not a strict plan. It is a way to think about the habits that help bones develop, remodel and remain supported throughout life.

 

The Bigger Picture

Peak bone mass is one of the body's greatest long-term investments. The skeleton spends the first few decades of life building the strongest foundation it can, then continues renewing itself for the rest of life.

The strongest bones are not built by one nutrient, one exercise or one stage of life. They are built through the partnership between movement, protein, collagen, minerals, hormones, recovery, specialised bone cells and the everyday habits that support growth and renewal.

Understanding peak bone mass changes the conversation. Bone health should not begin with fear later in life. It should begin with appreciation for what the body is building now.

For active men and performance readers, Strong Bones, Strong Performance: The Missing Link in Men's Fitness and Why Active Men Need to Think About Bone Health Too continue the movement and performance side of this topic.

Frequently Asked Questions

What is peak bone mass?

Peak bone mass is the highest amount of bone tissue most people achieve during early adulthood after years of growth, development and bone formation.

At what age do you reach peak bone mass?

Most people achieve around 90% of peak bone mass by approximately 18 years of age, with much of the remaining bone accumulated during the 20s before peak bone mass is generally reached.

Can adults still support bone health after peak bone mass?

Yes. Bones remain living tissue throughout life and continue to remodel. Weight-bearing activity, resistance training, balanced nutrition, adequate protein and recovery continue to matter.

Why is protein important for peak bone mass?

Protein supplies amino acids used to produce Type I collagen, the structural framework of bone. This framework is then strengthened by minerals such as calcium and phosphorus.

How does bone broth fit into a bone-friendly lifestyle?

Bone broth can be included as one protein-containing food within a varied diet. It provides protein and collagen-derived amino acids, but it works best alongside movement, calcium-rich foods, vitamin D, enough energy and overall healthy eating.

Summary

Peak bone mass explains why the early decades of life matter so much for lifelong skeletal health. Childhood, adolescence and the 20s are key years for building the bone foundation most people carry into adulthood.

The encouraging message is that bones remain alive and responsive throughout life. Move regularly. Eat well. Include enough protein. Fuel growth and training. Recover well. Your skeleton has been adapting to your life since the day you were born, and it will continue doing so for the rest of your life.

Selected References

·       National Health and Medical Research Council. Nutrient Reference Values for Australia and New Zealand.

·       International Osteoporosis Foundation. Peak bone mass and skeletal health resources.

·       Weaver CM et al. The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors.

·       Australian Institute of Health and Welfare. Bone health, physical activity and nutrition summaries.