Functional foods for bone health

PROFESSOR MARLENA KRUGER - Institute of Science and Technology

Brittle bones, fractures and chronic pain are suffered by many ageing women. Specialised nutrition and functional foods could mean reduced reliance on traditional pharmaceutical medications.

Maintaining bone health is essential for physical wellbeing, and when bone density is lost osteoporosis and fractures can occur. This is a particular risk for post-menopausal women, 10 to 11% of whom are affected by osteoporotic fractures.

Current treatment options include hormone-replacement therapy or the use of bisphosphonates, both of which can have side effects. Now, Professor Marlena Kruger, Dean of Graduate Research and Researcher Development at Massey University, is leading a platform of research investigating a variety of nutritional options that could help promote bone health.

Professor Kruger, who also holds the post of Professor of Nutritional Physiology at the Massey Institute of Food Science and Technology, has research interests which include lipids and bone health, the maintenance of mobility with ageing and the use of nutrition to support bone and joint health at different stages of life and among different ethnic groups.


Providing the scientific evidence

Anlene™ is a milk fortified with extra calcium and vitamin D. It is an example of a functional food targeted at improving bone health. Anlene™ was designed for Asian women on the proposition that drinking calcium-fortified milk throughout life would strengthen women’s bones sufficiently to prevent osteoporosis in countries where the condition is rife. But in order for the dairy industry to market the product, scientific evidence for its effectiveness was needed.

Professor Kruger researched the impact of calcium- and vitamin-fortified milk products and bioactives from milk on bone and joint health maintenance, using cell-based assay systems to screen for bioactivity, as well as using pre-clinical models and human intervention trials in New Zealand and Asia. These studies, funded by Fonterra Brands Singapore Ltd, demonstrated how milk and other dairy foods can influence bone growth or slow decay.


The role of Kiwi foods

Professor Kruger is now involved in further research into specialised nutrition and functional foods related to bone health. For example, she is investigating the interaction between New Zealand foods such as kiwifruit, mānuka honey or fish oils and soy phytoestrogens, in collaboration with researchers at the National Institute of Health and Nutrition in Tokyo. So far, results show that carotenoids from kiwifruit modulate bone breakdown, and that mānuka honey could act as a prebiotic, changing the bacterial population in the gut and altering mineral bioavailability as well as modulating molecular control of bone formation or resorption.

In her assessments of bone health, Professor Kruger has increasingly been looking at different ethnicities and the factors that affect bone health in each group. For example, she has studied the differences in the rate of bone loss in both males and females in seven countries in Asia, confirming that environment, diet and lifestyle have significant effects on bone health in these countries.

Counter to the general assumption that African women have strong bones and experience fewer fractures, more recent work showed that urban black post-menopausal women in South Africa in fact lose bone at similar rates to older Caucasian women. In the African women, obesity is also not a protective factor for bone density.

When good research underpins a valid health claim, which is then skilfully matched to a great consumer proposition, the simultaneous influence on consumer health and a country’s public health system can be profound.


International collaboration

Research that builds on Professor Kruger’s bone-health expertise is continuing, including a current collaboration with researchers in Singapore at the A*Star-NUS Clinical Imaging Research Centre and the Clinical Nutrition Research Centre. The project involves evaluating options for high-resolution bone imaging in order to gain additional information regarding bone structure, microarchitecture and the future risk of fractures in older women. This programme also involves searching for new markers of bone health, in addition to the current markers used routinely by Professor Kruger.

The potential for the development of functional foods is of particular interest to the food industry, which can sell larger volumes of food with higher profit margins by marketing them as having additional health benefits. The combination of public-good research and commercial research that Professor Kruger has achieved is not common.

When good research underpins a valid health claim, which is then skilfully matched to a great consumer proposition, the simultaneous influence on consumer health, reduced impacts on a country’s public health system and the effect on the economic wellbeing of producer companies can be profound.

This concept now forms the basis of one of New Zealand’s National Science Challenges—High Value Nutrition—which aims to use research excellence to enable the transformation of New Zealand’s food and beverage industry into an exporter of high-value, scientifically proven foods for health.

And consumers can expect to see affordable foods on our shelves with proven health benefits, and a future society which understands how to prevent the development of debilitating diseases such as osteoporosis or osteoarthritis safely through functional foods.

Project details

Funders Fonterra
Dates 2014 to 2017