Few people recognize the importance of the 206 bones in the human body or know enough about how these bones develop, grow strong and what keeps them strong as we age. Many people might be surprised to learn that we develop the strongest, most dense bone we’ll ever have by the time we reach our mid-20s! This is called achieving Peak Bone Mass and a healthy diet and weight-bearing and muscle-strengthening exercises are the key lifestyle factors in reaching Peak Bone Mass. Being physically active and playing sports – from a young age into adulthood – can positively contribute!
How our bones develop and grow
Bones are living, growing tissue made up of three major components that make them flexible and strong:
- Collagen, a protein that gives bones a flexible framework
- Calcium-phosphate mineral complexes that make bones hard and strong
- Living bones cells that remove and replace weakened sections of bone
Throughout our lives, our bones are constantly remodeling. When we’re young, our bodies make new bone faster than it breaks down old bone, and therefore the mass of the bone increases and becomes more dense and stronger. If you viewed it under a microscope, bone tissue looks like a honeycomb. The tighter and stronger the honeycomb fibers, the stronger the bone. Interestingly, in girls, the bone tissue accumulated during the ages of 11 to 13, approximately equals the amount lost during the 30 years following menopause.
Even after children and teenagers stop growing taller, they continue to make more bone than they lose, and this makes the bone denser. The more bone you have and the better the “architecture” of that bone at the time of peak bone mass is, the less likely you are to break a bone or get osteoporosis (a disease of the bone) later in life. After you reach peak bone mass, the balance between bone formation and bone loss starts to change. In midlife, bone loss speeds up for both men and women. Osteoporosis happens when you lose too much bone, make too little bone, or both.
The good news is that it’s never too early or too late to take steps to protect your bones.
If you want to build bone, jump!
Studies show that for both boys and girls, weight-bearing exercise, such as running and jumping, help to build bone. It’s important for children and teens to get adequate exercise to achieve peak bone mass. Muscle-strengthening exercises help to support the bone and make the body more flexible. Jumping rope or doing jumping jacks 100 times at least three days per week are examples of how to build bone mass.
A healthy diet helps to build and maintain bone health
If you eat a well-balanced diet with plenty of dairy or calcium providing foods, including fish, fruits and vegetables, and whole grains you should get enough of the nutrients you need every day. Research shows that Calcium and Vitamin D are essential to building and maintaining bone health throughout our lives. It’s important to get these nutrients from food first and only supplement for any shortfall in the diet. The recommended amount of calcium and vitamin D for children and young adults is:
RDA of Calcium RDA of Vitamin D
Age 0-6 months = 200 mg 400 IU
Age 7-12 months = 260 mg 600 IU
1-3 years = 700 mg 600 IU
4-8 years = 1,000 mg 600 IU
9-18 years = 1,300 mg 600 IU
19-30 years = 1,000 mg 600 IU
What can children and teens do to build and protect their bones?
Our bones benefit from the same things that keep the rest of our bodies strong and healthy – a well-balanced diet and exercise. Since nearly half our adult bone mass is acquired in the four years surrounding menarche in females and during pubescence in boys it is very important to get moving daily. Fortunately, activities like jumping off a jungle gym and the sprints required to play tag all qualify as weight-bearing activity, the type that helps build the strongest bones. Both force and impact count. Here are some tips to help children and teens build and protect their bones:
- Eat a well-balanced diet including calcium rich foods, such as milk, yogurt, green leafy vegetables and/or calcium fortified foods
- Be sure to get enough vitamin D through safe sun exposure, fortified foods or a vitamin
- Be physically active. Aim for at least 60 minutes of moderate physical activity every day, either in structured sports or at the playground (or put on music and dance!)
- Skip Dieting – this can damage your bone health rather than help
- Make healthy lifestyle choices including avoiding smoking and avoiding underage alcohol consumption since they are both harmful to bones
- Protect your bones by wearing protective equipment for sports such as a helmet and knee or elbow pads.
Heidi Skolnik, MS, CDN, FACSM is the Co-Chair of the NOF Subcommittee on Nutrition and Physical Activity and the President of Nutrition Conditioning, LLC.