Childhood and the teenage years are times of rapid growth and therefore when bone building occurs. As children grow, their bone mass increases until it reaches what is called peak bone mass (PBM). PBM is the greatest amount of bone an individual can attain. PBM is reached in the late teens and early 20’s. It then stays relatively stable until around the age of 50 when bone mass starts to decline. Teenagers who have higher PBM reduce their risk of osteoporosis later in life.

The key factors that impact PBM are:

  1. Calcium intake
  2. Vitamin D
  3. Physical activity
  4. Maintaining a healthy weight (avoiding over or under nutrition)
  5. Hormones



Calcium is needed for normal mineralization of the bone and cartilage matrix. The current recommendations for daily calcium intake are as follows:


1 – 3 years

500 mg per day

4 – 8 years

700 mg per day

9 – 11 years

1000 mg per day

12 – 19 years

1300 mg per day


The best sources of calcium are:

  • Dairy products – milk cheese, yoghurt (300 – 400mg per serve)
  • Leafy green vegetables – broccoli, cabbage, bok choy, spinach (50 – 100mg per cup)
  • Soy and tofu – 1/2 cup provides around 150 mg calcium
  • Fish – sardines, tinned salmon with soft bones (400mg per ½ cup)
  • Nuts and seeds – brazil nuts, almonds, sesame seed paste, around 50mg per 15 nuts
  • Calcium-fortified breakfast cereals – amount of calcium varies between brands
  • Calcium-fortified milk alternatives – if consuming a milk alternative such as almond, rice, soy or oat milk check that it contains added calcium.


Vitamin D

Vitamin D is needed for the body to absorb calcium. For Australians the main source of Vitamin D is the sun. Vitamin D is produced when our skin is exposed to UVB light from the sun. During summer, only a few minutes a day of sun exposure in the early morning or late afternoon is adequate, and 2-3 hours per week during winter. A limited number of foods contain small amounts of vitamin D such as egg yolks, liver, oily fish and some products that may be fortified with vitamin D (e.g. milk, margarine and cereal).


For further reading on bone health go to: