Osteoporosis is a skeletal disease characterised by a reduction of bone strength and increased risk of bone fracture due to a loss of bone mineral density. In New Zealand, someone fractures a bone every six minutes due to osteoporosis, making this a costly disease not just for the individual in terms of quality of life, but for society as a whole.
Combined with osteomalacia and osteopenia (low bone mineral density), it is a significant burden on the public health dollar, at an estimated $1.15 billion per year. Though peak bone mass is reached in our early twenties, our bones are in a constant flux of being broken down and built up, affected by both genetic and environmental factors.
Bone loss (when the amount broken down overtakes accumulation) naturally occurs around the mid-thirties, and though people may think their genes are the most important element in bone loss and risk of osteoporosis, diet and exercise exert the most influence.
Most people are aware that calcium is the most significant mineral that affects bone health. Combined with phosphorus (another mineral) it provides bone with its hard shell to maintain strength. However bone is made up mostly of collagen, a protein that provides a soft framework allowing for flexibility. It’s important to have a good dietary intake of these minerals to protect against excessive bone loss. Calcium is taken from our bone when there are low levels of calcium in the bloodstream.
In addition to protein and calcium, vitamin D, magnesium and vitamin K are all important cofactors for reaching and maintaining peak bone mass.
Though there may be a place for supplementing with nutrients specifically for bone health, there have been mixed results when studied in clinical trials. Though calcium supplementation is a part of an osteoporosis treatment plan (where recommendations are 1500mg per day), it has only shown somewhat modest effects on increasing bone mineral density, and like any supplement, only useful in this capacity if a person is low in dietary calcium.
More recent research points to an increased risk of cardiovascular disease in certain populations with supplemental calcium. Dietary sources therefore become our best avenue for obtaining calcium to prevent the onset of osteoporosis, with milk, cheese and yoghurt rich sources of calcium and also providing protein, some magnesium, vitamin K and vitamin D.
Incorporating milk into meals across the course of the day will help obtain the beneficial nutrients. Don't limit it to just drinking — using milk in cooking will up your intake and this cauliflower with broccoli cheese sauce is a great side dish to any main meal or could indeed be a meal itself.
Lifestyle factors that negatively impact our health in general, such as smoking, excessive alcohol intake and physical inactivity, can increase bone loss at any age. Along with choosing to be smoke-free and drinking appropriately to reduce free radical damage that negatively impacts bone formation, resistance training and small amounts of high impact activity provide stress to the bone that enables it to adapt and maintain its strength.
This is especially important as we age, with the rate of bone resorption increasing in comparison to bone formation. Women are at greater risk given the reduction in circulating oestrogen, which is important for bone health. A good intake of nutrients involved in bone health, along with healthy lifestyle habits are the best ways to prevent excessive bone loss as we age.
Through her subscription service of meal plans and nutritional support, nutritionist Mikki Williden helps people manage their diets in an interesting way, at a low cost. Find out more at mikkiwilliden.com