CSIRO Human Nutrition
Fast facts
The micronucleus assay and other molecular and cytogenetic techniques are being applied to:
Assess genetic damage in human populations;
Monitor damage from accidental, occupational or therapeutic exposure to carcinogens;
Screen new chemicals for human and environmental safety;
Identify abnormal sensitivity to genotoxic chemicals and radiation; and
Identify dietary components that can protect against spontaneous and radiation-induced DNA damage.
Additionally:
Personalised diet, health and lifestyle guidance is increasingly seen as a major new business opportunity.
Foods for healthy genes
Food and nutraceutical manufacturers can play a larger role in enhancing human genetic health by introducing products into the marketplace that guard against or repair damage to the human genome - all of an individual’s genes and chromosomes. Nutrigenomics is the new science of understanding how your unique genetic make-up determines your dietary requirements and how your diet can alter the structure of your chromosomes and genes and their expression.
Personalised diet, health and lifestyle guidance is increasingly seen as a major new business opportunity.
The CSIRO Human Nutrition Centre, managed by CSIRO Food and Nutritional Sciences, is currently determining why people respond differently to certain changes in dietary patterns or as a result of supplementation with certain vitamins such as folic acid. This information will become increasingly useful in the future when dietary advice can be better targeted to an individual’s unique genetic background to optimise health.
Genome health and nutrigenomics
Genetic damage can occur as a result of exposure to certain types of radiation or chemicals, micronutrient deficiency - and naturally, through the ageing process. Such DNA mutations have been shown to increase the risk of developmental defects and accelerate the development of cancer and degenerative diseases of old age. A reliable technique, micronucleus assay, assesses genetic damage by detecting and measuring microscopic damage to cellular DNA and cell death in human cells. The technique is also being used to investigate the benefits of particular micronutrients.
The micronucleus assay could help identify people who are likely to develop cancer or Alzheimer’s Disease. It can also be used to predict the radiation-sensitivity of normal tissues and tumours, to assist in developing more effective personalised treatments for cancer patients. A simple test, using lymphocytes (white blood cells) or mouth epithelial cells (from inside the cheek), allows damage to the cell’s chromosomes to be visualised as small spherical structures containing un-repaired or mis-repaired DNA fragments or misplaced whole chromosomes. The DNA lesions are known as "micronuclei" - as shown in this image,
How can foods help?
In the course of a lifetime, human DNA is damaged by
- inadequate diet,
- exposure to radiation,chemicals and
- as a result of ageing.
This damage appears in cells as tiny fragments, micronuclei that have broken off from the cell's chromosomes. Such mutations can lead to the development of cancers and diseases such as Alzheimer's Disease.
Personalised dietary requirements for genome health and wellbeing are the expected outcome of nutrigenomics.
People with above average levels of damage to DNA have twice the risk of cancer of those with below average DNA damage rates. CSIRO studies have shown that the extent of DNA damage can be reduced by up to 25% by taking 3.5 times the recommended daily intake of folic acid and vitamin B12. Evidence also suggests that the risk of breast cancer may be reduced by adequate folic acid intake.
Several micronutrients - vitamins and minerals - are required for DNA synthesis, repair and programmed cell death. These processes have to work well if the risk for cancer is to be minimal.
Results from this research will form the basis for recommended dietary allowances (RDAs) specifically aimed at enhancing capacity for maintaining stable and healthy genes at various stages of life. The concept of RDAs for genomic stability was developed in this project. Personalising dietary requirements for genome health is the ultimate goal.
Recent studies from the same project have identified that, apart from folate and vitamin B12, moderate increases in the intake of certain micronutrients such as calcium, niacin, retinol and vitamin E, are also associated with better genome health.
Diet, health and lifestyle
Our researchers take an integrated approach to determining how to achieve good health. Food, exercise, attitude, lifestyle and genetics are all important components in an individual’s health status. While there is no single formula for achieving optimal health, the importance of food in the equation is pivotal.
There is enormous scope for businesses promoting health and wellbeing to partner with CSIRO Food and Nutritional Sciences in its goal to improve community health through food and diet. The research team is renowned for high quality trials in vivo and in vitro, and has an excellent track record in substantiating health claims about foods.