Healthy eating habits/Eating for Bone Health
A guide to optimising bone strength and preventing osteoporosis for young women.
Why is bone health important?
Why worry about bone health at your age? Isn’t it just old women who become hunched over and frail? Osteoporosis is a condition of the musculoskeletal system in which a person's bones become fragile and brittle, leading to an increased risk of fractures. These fractures can lead to chronic pain, disability and a loss of independence. To help prevent osteoporosis, we need to exercise and nourish our bones throughout our lives. Osteoporosis is a major health problem in Australia; with 1 in 5 women over 65 years developing osteoporosis.
Changes in Bone Mass – Peak Bone Mass
Our bone strength develops until the age of 25-30 years; we deposit minerals such as calcium into our bones making them dense and strong, this is called our peak bone mass. From the age of approximately 30 years we experience a slow decline in our bone density/strength, this bone loss accelerates after menopause when hormonal changes result in more rapid losses. Osteoporosis occurs if our bones lose too much density, so now is the time to build your bones. After you reach your peak bone mass you can only maintain or slow the loss of bone, so start your life with a big ‘bank’ to reduce your risk of developing this crippling disease.
How can we build and maintain strong bones?
What nutrients do we need for strong bones?
Calcium and Phosphorus play a major role in bone strength, and are of prime importance in the prevention of osteoporosis. These minerals along with Magnesium, Vitamin D, Vitamin B12 and others all play a role in building up strong bones.  Consuming adequate amounts of these minerals along with regular weight bearing exercise such as jogging, skipping and aerobics helps us to optimise our bone strength until the age of 30 and then helps to slow the loss of bone density with age.  
How much calcium are we getting?
The average daily calcium intake of 19-24 year old women falls short of the recommended daily amount by 250mg/day; this is equivalent to the amount of calcium found in approximately 1 cup of milk. 
How can we get enough calcium in our diet?
Calcium is found predominantly in milk and other dairy foods. Other sources include bony fish, legumes and certain nuts, fortified soy and other milk alternatives, and fortified breakfast cereals. It is recommended that we consume 2.5 serves of dairy/alternatives each day to meet our requirements.
1 serve is equivalent to:
- 1 cup of milk (250ml);
- 2 slices (40g) of hard cheese, such as cheddar;
- ½ cup (120g) ricotta cheese;
- ¾ cup (200g) yoghurt;
- 1 cup (250ml) soy, rice or other cereal drink with at least 100mg of added calcium per 100ml.
Tips to optimise calcium absorption
- Spread your consumption of calcium containing foods out across the day.
- The sugar (lactose) and protein in milk promote calcium absorption; therefore dairy is a great source.
- Absorption is promoted by vitamin D, which is also found in dairy foods.
- Choose calcium fortified products such as cereals, juices and tofu.
- Add in an extra serve of dairy in you day; yoghurt as a snack or a fruit smoothie made with milk are great options.
- Ensure you eat green leafy vegetable such as spinach, kale or broccoli each day.
- Eating a small handful of almonds and dried figs as a snack will add to your calcium intake.
Foods that reduce calcium absorption
Avoid eating these foods at the same time as your calcium containing foods:
- Phytic acid containing foods such as cereals and legumes;
- Oxalic acid containing foods such as in spinach, rhubarb, beetroot and tea;
- Caffeine, alcohol and salt increase the amount of calcium lost through urine, therefore limit your consumption of these.
Milk alternatives: differences and benefits
There is an extensive variety of milk and milk alternatives on the market and it can become confusing to know what the best option is. All dairy milk alternatives need fortifying to match the nutritional content offered in cow’s milk. So whatever type of milk you consume; it is important to look for one which is fortified with calcium. You can check this by looking at the nutrition information panel on the back of the package and ensuring there is at least 100mg of calcium per 100mls. It is also important in non-dairy varieties to be aware of added sugar and salt. It is best to choose unsweetened options with under 120mg sodium per 100mls. However alternatives to dairy milk do offer benefits such as being lactose and dairy free for those who are intolerant or vegetarian, milks which come from nuts have the added benefit of healthy fats, antioxidants, vitamins and minerals.
- For information on consuming a balanced diet see the Australian Guide to Healthy Eating and Dietitians Association of Australia - Smart Eating for you
- For more detailed information regarding osteoporosis prevention go to Osteoporosis Australia
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- Osteoporosis Australia. (2013). Calcium. Retrieved from http://www.osteoporosis.org.au/
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