Eat (less) for health

The new edition of the Australian Dietary Guidelines was released by the National Health and Medical Research Council of Australia (NHMRC) this month. The documents include the Dietary Guidelines (for adults and children), the Infant Feeding Guidelines and a variety of educational and promotional materials.^1,2 The background literature reviews are also available, although it needs to be noted that these are not comprehensive and only address selected areas of nutrition.

The Guidelines had a low-key launch, announced at the last minute to a small number of journalists and interested health workers. If the aim was to reduce publicity and avoid any hint of controversy, it was a successful exercise. However, Australia has much to celebrate in regard to the benefits brought to the nation by a century of improving nutrition. The new sets of Dietary Guidelines and associated materials continue this tradition of improving health through better nutrition and providing the scientific basis for health promotion interventions.

Better nutrition has made a major contribution to the dramatic improvement in the health and survival of Australians since Federation. In 1901, the infant mortality rate was 105 per 1000 live births and life expectancy was 55 years.³ By the end of World War II, and before modern vaccinations and antibiotics became available, infant mortality had declined to 28 per 1000 live births and life expectancy had reached 72 years. Now, life expectancy is 73 years for Indigenous Australians and 82 years for other Australians.^4,5 At Federation, approximately one-third of the population died before the age of 50 years, whereas today closer to 95% survive beyond that age.⁶

A substantial part of our advancement in health is due to improvements in our food supply, in the quantity and quality of food products. Advances in food technology, better packaging, the use of preservatives and food additives and the universal availability of refrigeration have given us one of the healthiest food supplies in the world.

The new Dietary Guidelines were developed in the context of an obesity epidemic in Australia, although there is evidence that the rate of increase has now slowed, and perhaps even stopped.⁷ The Guidelines are remarkably like the old ones because a review of the literature (some 50 000 academic papers) has confirmed the relevance of the previous nutrition advice given by the NHMRC. The Guidelines have been reordered and reworded to reflect the emphasis on overweight and could perhaps be retitled ‘Eat (less) for health’. A major nutrition intervention was published at the same time as the new Dietary Guidelines.⁸ The Prevencion con Dieta Mediterranea (PREDIMED) trial (n = 7447) randomised participants into three groups: (1) Mediterranean diet plus olive oil; (2) Mediterranean diet plus nuts; and (3) a control group. The intervention was similar to the diet advocated in the Australian Dietary Guidelines. Interestingly, the trial was stopped after 5 years because of adverse health outcomes in the control group. Although that study again substantiated the benefits of a healthy diet on the effects of non-communicable diseases, the question for health promotion practitioners will be whether the intervention (3-monthly education groups) is feasible and sustainable on a larger scale.

The development of the Dietary Guidelines was hampered by a lack of information on food consumption in Australia, with the last major nutrition survey being 20 years old. Australia is one of the few developed nations that does not monitor its food supply on a regular basis. One feature of the Dietary Guidelines is the first word, ‘Enjoy’, which reflects the health promotion ethos, a word originally borrowed from the Japanese Dietary Guidelines,⁹ reflecting a positive message for good nutrition. The promotion of breastfeeding remains one of the Australian Dietary Guidelines, as well as providing the framework for the Infant Feeding Guidelines. Remembering that Barker¹⁰ has speculated that the ‘French Paradox’ of lower rates of heart disease were due to an early emphasis on maternal infant nutrition. This approach mitigates the developmental origins of adult disease hypothesis, whereby nutrition practices during early development can influence disease outcomes later in life.

The challenge for the health promotion community is to find ways of implementing the nutrition advice and supporting and maintaining behaviour change. Can we provide information for the entire community while making healthy food choices easier choices, such as by using more meaningful food labelling (traffic lights), taxing high-sugar drinks, high-fat foods and salty snacks and providing healthier options for eating out and take away foods while reducing junk food advertising? We can easily summarise the Guidelines in a few words:

Breastfeed, eat less (while making healthier choices) and move more.

However, getting all Australians to follow them may be a little more difficult.

CWB was deputy chair of the NHMRC Dietary Guidelines Working Party and has been involved in the preparation of all the previous editions of the NHMRC Dietary Guidelines.