Back to basics: Bone Health

This article is written by Accredited Practising Dietitians from FEEDinc. Nutrition Clinic and is aimed at Health Professionals to provide the most up-to-date information on bone health for their patients.

Role of calcium in the body

Did you know our bodies cannot naturally make calcium?1 So getting it through our diet is essential for maintaining bone health and is why calcium rich foods are one of the five food groups the Australian Dietary Guidelines recommend we consume every day.2,3

99 per cent of the body’s calcium is found in our bones, with a small amount also being absorbed into the bloodstream and playing an essential role in the healthy functioning of the heart, muscles, blood and nervous system.2 Combined with other minerals, like phosphorus, calcium is used to form hard crystals that give our bones their strength and structure.2

When we do not consume enough calcium, our body withdraws calcium from our bones to use for other parts of our body.4 Overtime, if the body withdraws more calcium than it deposits, our bones weaken and become brittle, increasing our risk of developing things such as osteoporosis.4

Calcium requirements

The recommended dietary intake of calcium depends upon our age and gender.2 For example, calcium requirements are high in our teenage years as our peak bone mass, the point at which our bones are strongest, is achieved by our early twenties.2 It is also during this time that our bodies are their most efficient in absorbing calcium and we see rapid growth of the skeleton.2 With age, however, this absorption efficiency decreases and is one of the reasons we need to consume higher amounts of calcium.2

Calcium and dairy food

The easiest way to achieve the recommended level of calcium intake each day is to consume calcium rich foods.1

Dairy foods such as milk, yoghurt, cheese and calcium-fortified products (e.g. breakfast cereals, fruit juices and bread), have long been known for their important role in bone health, as they contain a high level of calcium and are most readily absorbed by the body.1,4 Dairy foods also provide other various health benefits, such as protecting us against heart disease and stroke, high blood pressure and some cancers.5 Dairy foods are also an excellent source of nutrients including protein, iodine, vitamin A, vitamin D, riboflavin, vitamin B12 and zinc.5

Most people need at least 2-3 serves of dairy foods each day.1 The current recommendations for minimum numbers of serves of the dairy food group each day for adults and children is shown in the table below.3

Age (years) No. of serves per day 
Children  Milk, yoghurt, cheese and/or alternatives
Girls   
2-3  1 1/2 
4-8  1 1/2 
9-11 
12-13  3 1/2 
14-18  3 1/2 
Boys   
2-3  1 1/2
4-8 
9-11  2 1/2 
12-13  3 1/2 
14-18  3 1/2 
Adults   
Women   
19-50  2 1/2 
51-70 
70+ 
Men   
19-50  2 1/2 
51-70  2 1/2 
70+  3 1/2 
Adapted from 2013 Australian Dairy Guidelines. Dairy food group includes milks, cheese, yoghurt and/or alternatives*.
*Alternatives include: 250ml soy, rice or other cereal drink with at least 100mg of added calcium per 100ml.


How much dairy to eat?

A serve of dairy is equivalent to 1 cup of fresh or UHT long-life milk (250ml), 2 slices of hard cheese (40g), 1/2 cup of ricotta cheese (120g) or 3/4 cup of yoghurt (200g).1

Low or reduced fat milk, yoghurt and cheese choices are recommended for most people 2 years or over.1 Reduced fat varieties are not suitable for children under 2, owing to their high energy needs required for growth.1

The following non-dairy alternatives contain approximately the same amount of calcium as a serve of milk, yoghurt or cheese:

  • 1 cup (250mls) soy, rice or other cereal drink with at least 100mg of added calcium per 100ml
  • 100g almonds, skin on
  • 60g sardines, canned in water
  • ½ cup (100g) canned pink salmon, with bones
  • 100g firm tofu1

Tips for including dairy into your day

Here are some healthy and convenient ways of including more dairy into your day:

  • Breakfast – milk or yoghurt on cereal, in porridge or in smoothies
  • Morning tea – milk-based coffee
  • Lunch – slice of cheese on a sandwich
  • Afternoon tea – tub of yoghurt or cheese and vegetable sticks
  • Dinner – grated cheese or a yoghurt-based dressing on top of a main meal
  • Dessert – occasional creamed rice or ice cream. These are considered a discretionary choice and should only be eaten occasionally, as they are relatively high in kilojoules, fat and sugar. 
1/2 

References

  1. Healthy Bones [Internet]. Victoria, Australia: Dairy Australia; [year of publication unknown]. Bone FAQs; [publication date unknown] [cited 2018 October 18]. Available from: http://www.healthybones.com.au/bone-faqs/bone-faqs
  2. Osteoporosis Australia [Internet]. Broadway NSW: Osteoporosis Australia Medical & Scientific Advisory Committee; 2014. Calcium; [publication date unknown] [updated 2017 July 14; cited 2018 October 18]; [about 5 screens]. Available from: https://www.osteoporosis.org.au/calcium
  3. National Health and Medical Research Council (NHMRC). Australian Dietary Guidelines [Internet]. Canberra, Australia: NHMRC; 2013 [cited 2018 October 18]. Available from: https://nhmrc.gov.au/about-us/publications/australian-dietary-guidelines
  4. Better Health Channel [Internet]. Victoria, Australia: State of Victoria; [year of publication unknown]. Calcium; [publication date unknown] [updated 2013 April; cited 2018 October 18]; [about 7 screens]. Available from: https://www.betterhealth.vic.gov.au/health/HealthyLiving/calcium
  5. Heart Foundation [Internet]. [Location unknown]; [year of publication unknown]. Healthy Dairy Foods; [publication date unknown] [cited 2018 October 18]; about 3 screens]. Available from: https://www.heartfoundation.org.au/healthy-eating/food-and-nutrition/dairy-foods