It is said that you are what you eat, and that is very true for your skeleton too. Bones are formed of living tissue that undergoes a process of constant renewal and, like the body as a whole, they need the right nutrients to grow and thrive.
The World Osteoporosis Day campaign is dedicated to raising public awareness of the important role of nutrition to support bone health at all stages of life. The campaign ‘Serve up bone strength’ is spearheaded by the International Osteoporosis Foundation (IOF) and its more than 230 national osteoporosis-related societies worldwide.
The key campaign message is that, for optimal bone health, people of all ages should have a balanced diet which ensures adequate levels of calcium, vitamin D and protein—as well as specific micronutrients such as vitamin K, magnesium, zinc, and carotenoids.
Professor John Kanis, President, IOF, explained, “Our skeleton is very much like a house. It needs to be built with the right material to keep the structure strong and maintained over time to avoid long-term damage. That’s why a diet rich in dairy products, oily fish, fruits and vegetables can provide us with the essential nutrients that are the key building blocks of strong bones.”
Changing Nutritional Needs With Age
Depending on what stage of life you are in, you may need more of the key nutrients that impact bone health. That is why nutritional recommendations for calcium, vitamin D and protein are age- and gender-specific. The varying requirements reflect the primary objectives for good bone health, focusing on:
- • achieving genetic potential for peak bone mass in children and adolescents
- • avoiding premature bone loss and maintaining a healthy skeleton in adults
- • preventing and treating osteoporosis in seniors
Children and adolescents are advised to have higher nutritional intake of the key bone-building nutrients calcium and protein. This is because they are at the critical period for skeletal development, a stage in life when they should be attaining their full genetic potential for peak bone mass.
By optimising their bone mass potential, a young person has more bone in reserve from which to draw in adulthood. This is important because, unlike in younger years, adults cannot replace bone tissue as quickly as it is lost.
New research shows that the optimal foundation for strong bones is in fact set even before birth—an expecting mother’s diet and vitamin D status may affect the bone mass potential of the developing foetus. This early attention to nutritional factors is important because studies estimate that a 10 percent increase in peak bone mineral density (BMD) could delay the development of osteoporosis by 13 years.
Osteoporosis is a chronic, progressive disease which affects millions of older adults worldwide. Despite being known as the ‘silent disease’ because of its lack of apparent symptoms, the disease is very common. It affects approximately one in three women and one in five men aged 50 years or over.
Osteoporosis causes bones to become weak, fragile, and more prone to fracture. In a senior with osteoporosis, a minor slip on the pavement can result in a life-threatening hip fracture. Or, a severely debilitating spinal fracture can occur simply as a result of a sneeze, or bending over to tie a shoelace. Such fractures may have devastating long-term consequences, including chronic pain, disability and loss of physical independence.
In order to help sustain their bone health and muscle function, seniors are also advised to have higher dietary intakes of certain bone-healthy nutrients. One reason for the higher vitamin and mineral requirements in older adults is that the body is less able to produce, absorb or retain certain nutrients.
For example, in seniors there is decreased intestinal absorption of calcium, which is exacerbated if vitamin D levels are low too. Vitamin D is produced in the skin with exposure to sunlight, and only a minor part of our vitamin D needs are met through the diet. The problem is that older people’s skin is also approximately four times less able to synthesise vitamin D than a younger person’s skin.
Given the indoor-lifestyle most seniors have and the various physiological factors related to ageing, it is therefore very common for seniors to have poor vitamin D status. As a result IOF recommends vitamin D supplementation of 800 to 1000 international units (IU) a day for falls and fracture prevention in seniors aged 60 years and over. Vitamin D supplementation at these levels has been shown to reduce the risk of falls and fractures by about 20 percent.
Widespread Calcium And Vitamin D Deficiencies
Healthy bone (left) and an osteoporotic bone (right).
A report to be issued by IOF for World Osteoporosis Day underlines how recent lifestyle trends are leading to poor diet and nutrient deficiencies in people of all ages, and especially in children. This is a growing cause of concern as children who are not getting enough bone-building nutrients, combined with sedentary lifestyles in which they do not have enough exercise, will be at higher risk of osteoporosis later in life.
In many countries, milk and dairy products comprise the main stay of calcium intake for most children, yet a decline in milk consumption by children has been observed across the world during the last few decades; this is likely related to the growing consumption of soda and sweetened beverages.
In Asia, low calcium intake may especially be a critical issue. The median dietary calcium intake for the adult Asian population is approximately 450 mg/day, far below international recommendations for calcium intake of between 1,000 and 1,300 mg/day. In China, estimates from the Health Status Survey in 2002 indicated that less than 10 percent of Chinese citizens had an adequate dietary intake of calcium.
Many Asian diets are low in calcium partly because calcium-rich dairy foods such as milk, cheese and yoghurts are not as common in the diet, and dairy foods are avoided due to the high prevalence of lactose intolerance.
Efforts to raise calcium intake in Asia should therefore also focus on the many non-dairy foods that contain calcium and which are more common to the Asia diet. These foods include, among others, almonds, bok choy, napa cabbage, soy beans, beans and lentils, canned fish with bones (e.g. sardines), oysters, sesame seeds, calcium-set tofu, sea weeds, and wakame.
In many countries, calcium-fortified soy milk, orange juices and cereals are commonly available. Some mineral waters also contain calcium. In addition, it is important to remember that certain yoghurts and low-lactose milk products can be consumed by many people with lactose sensitivities.
With a few exceptions, countries in South and Southeast Asia have been shown to have widespread prevalence of vitamin D deficiency and insufficiency, in both genders and all age groups. This is true of other parts of the world as well.
Increasingly urban, indoor lifestyles, smog, and sunavoidance may lead to vitamin D deficiency. Concern about low vitamin D levels in the population has led to recommendations in several countries for vitamin D supplements to be given to infants and young children.
Asia Foresees An Osteoporosis Epidemic
It is said that prevention is better than cure, and that certainly applies to osteoporosis and fracture prevention. A lifetime of bone-healthy nutrition, combined with regular physical exercise and smart lifestyle choices (such as no smoking and moderate alcohol intake) will help set the foundation for good bone health in later life.
Promotion of such preventive strategies among the population at large is especially critical for the Asian-Pacific region, perhaps more so than for any other region of the world.
In its ‘Asian Audit’ reports of 2009 and 2013, IOF warns of a dramatic rise in osteoporosis-related fractures in the region with the ageing of the population. The number of people aged over 70 years in the Asia-Pacific will increase by approximately 230 percent by 2050. By that time, China and India, the most populous countries in the world, will have almost 430 million people aged 70 or over.
With this enormous increase in the elderly, hip fracture rates—which have already risen two- to three-fold in most Asian countries during the past 30 years—are expected to double by 2050.
In countries such as Vietnam, Sri Lanka, Philippines and Pakistan less than 50 percent of hip fractures are surgically treated. A patient who must pay out of pocket for surgery may face impoverishment or, without surgery, extreme disability. Unless strategies are undertaken to reduce future fracture rates, the result will be a massive rise in disability, dependency, and soaring costs to Asia’s healthcare systems.
IOF urges governments throughout Asia to step up prevention efforts. Osteoporosis and musculoskeletal diseases should be a priority issue on national health-care agendas. As a first step, public health authorities should address widespread vitamin D deficiency and low calcium levels, and work to raise public awareness about the importance of nutrition and exercise, especially among the younger populations.