August 2021. About this episode: The largely plant-based Mediterranean diet is a well-studied dietary pattern. Research tells us that following…
Australian Dietary Guidelines: Under review
Australian Dietary Guidelines: Under review
The Australian Dietary Guidelines are under review. Where do nuts sit in the current (2013) Guidelines? And why it is critical that they feature more prominently in the revised Guidelines?
The review process
In mid-2020, the Australian Government announced funding for a review of the Australian Dietary Guidelines (1). The National Health and Medical Research Council (NHMRC) will lead this task, which will take around four years to complete.
A key part of the NHMRC’s work will involve reviewing and assessing the scientific evidence, including the newest published research. The outcomes of this will inform the direction of the revised Guidelines.
It’s not an easy task – for nuts and health alone, there are more than 2,000 published papers!
About the Guidelines
The Australian Dietary Guidelines offer guidance on the amount and kinds of foods that we need to eat for health and wellbeing.
Following the guidelines gives Australians the best chance of getting enough of the nutrients needed for good health, and can also help reduce the risk of chronic health conditions.
Where do nuts sit in the 2013 Guidelines?
Nuts are included in one of the five food groups – the ‘Lean meats and poultry, fish, eggs, tofu, nuts and seeds, and legumes/beans’ group. This group is often referred to as the ‘protein’ group, as the foods are considered ‘protein rich’.
The guidelines also recommend Australians enjoy a wide variety of nutritious foods from each of the five food groups every day. However, for nuts specifically, the guidelines state they should only ‘be used occasionally, as a substitute for other foods in the group’.
Nuts are ‘lost’ within the current ‘protein rich’ food group, rather than viewed as essential in their own right. Nuts must have greater prominence in the updated Australian Dietary Guidelines.
Why does this need to change?
Nuts are unlike other ‘protein group’ foods
Nuts have a very different nutritional profile (and therefore, different health benefits) to the other foods within the ‘protein-rich’ food group.
For instance, they contain plant-based protein (unlike red meat, poultry, fish and eggs), are rich in unsaturated fatty acids (unlike tofu and legumes/beans, for instance) and provide dietary fibre (unlike animal-sourced ‘protein rich’ foods).
Reiterating these differences, the drafts and modelling papers for the 2013 Australian Dietary Guidelines state: ‘Given their very different nutritional composition, modelling with nuts and seeds as a separate group was undertaken in the development of both the Foundation and Total Diets’.
In addition to plant-based protein, unsaturated fatty acids and dietary fibre, nuts are also rich in polyphenols, phytosterols and micronutrients including folate, several valuable forms of vitamin E, selenium, magnesium and other minerals (1).
Nuts are essential every day
The 2013 Guidelines state that nuts are only to be used occasionally, as a substitute for other foods in the ‘protein-rich’ group. This is due to the energy-density of nuts.
Yet, convincing and consistent evidence shows that regular nut consumption is not linked with weight gain (2-6). And research over the past decade suggests that up to 30 per cent of the kilojoules in nuts are not absorbed (7-10).
Nut intake reduces chronic disease risk
Nuts play a role in delivering essential nutrients, and in providing evidence-based significant health benefits. Since the release of the 2013 Guidelines, the evidence has increased dramatically on the benefits of regular nut consumption on chronic disease risk reduction (11-16). Now, more than 2,000 published papers, including high-quality systematic reviews and meta-analyses, provide scientific evidence for the health effects of nut consumption.
A handful of nuts every day, as part of a balanced diet, is just as essential for good health as eating enough fruit and vegetables (17).
Nut intake is chronically low
Australian Health Survey (AHS) data shows that, like fruit and vegetable intake, nut intake is chronically low.
A secondary analysis of the survey found just 2% of Australians consumed 30g nuts a day (18). In comparison, AHS survey data showed 7.5% of adults were meeting the guidelines for vegetable intake, and 51% of adults were meeting the recommended daily serves of fruit (19).
A greater prominence for nuts within the Guidelines will improve intake, helping to shift national dietary patterns towards healthier choices.
Nut intake is chronically low, yet benefits are high. Just 2% of Australians meet the daily target of 30g a day (18). Regular consumption is associated with chronic disease risk reduction.
According to the World Health Organisation, increased consumption of whole grains, vegetables, fruit, nuts and pulses is one of the five key principles of a healthy diet.
Human and planetary health
Future dietary guidelines globally must transform to integrate both human and planetary health (20,21). The EAT-Lancet Commission’s Planetary Health Diet provides global guidelines, designed with environmental sustainability in mind. It emphasises a plant-forward diet – where nuts, whole grains, fruits, vegetables and legumes comprise a greater proportion of foods consumed.
In line with this, the EAT Lancet Commission’s 2019 report states that to achieve dietary recommendations for improved human and planetary health, global intake of nuts needs to double (22). And it suggests the scientific target for nuts as 50g/day (with a range of 0-70g).
Did you know? Nuts – in all their forms – were not included in the 2013 dietary recommendations for children 2–3 years or younger, due to concerns about choking. But nut butters, nut flours or meals, and other nut products suitable for this age group, should be recommended. Evidence suggests that prolonged avoidance of potentially-allergenic foods, like nuts, may increase the risk of developing a food allergy (23). Nut-based products provide essential nutrients that are needed for growth and development.
- NHMRC. Eat for Health – Australian Dietary Guidelines. Providing the scientific evidence for healthier Australian diets. 2013. Available at: https://www.eatforhealth.gov.au/guidelines
- Flores-Mateo, G., et al., Nut intake and adiposity: Meta-analysis of clinical trials. Am J Clin Nutr, 2013. 97(6): 1346–55.
- Li, H., et al., Nut consumption and risk of metabolic syndrome and overweight/obesity: A meta-analysis of prospective cohort studies and randomized trials. Nutr Metab (Lond), 2018. 15: 46.
- Guarneiri, LL., et al., Intake of Nuts or Nut Products Does Not Lead to Weight Gain, Independent of Dietary Substitution Instructions: A Systematic Review and Meta-Analysis of Randomized Trials. Adv Nutr, 2021. 12(2): 384–401.
- Julibert, A., et al., Metabolic Syndrome Features and Excess Weight Were Inversely Associated with Nut Consumption after 1-Year Follow-Up in the PREDIMED-Plus Study. J Nutr, 2020. 150(12): 3161–70.
- Wang, J., et al. Mixed tree nut snacks compared to refined carbohydrate snacks resulted in weight loss and increased satiety during both weight loss and weight maintenance: A 24-week randomized controlled trial. Nutrients 2021; 13:1512.
- Novotny JA., et al., Discrepancy between the Atwater factor predicted and empirically measured energy values of almonds in human diets. Am J Clin Nutr, 2012. 96(2):296-301.
- Baer D., et al., Measured energy value of pistachios in the human diet. British Journal of Nutrition, 2012. 107(1): 120-25.
- Baer DJ., et al., Walnuts Consumed by Healthy Adults Provide Less Available Energy than Predicted by the Atwater Factors. The Journal of Nutrition, 2016. 146(1): 9–13.
- Baer DJ., Novotny JA., Metabolizable Energy from Cashew Nuts is Less than that Predicted by Atwater Factors. Nutrients, 2018. 11(1): 33.
- Aune, D., et al., Nut consumption and risk of cardiovascular disease, total cancer, all-cause and cause-specific mortality: A systematic review and dose-response meta-analysis of prospective studies. BMC Med, 2016. 14(1): p. 207.
- Afshin, A., et al., Consumption of nuts and legumes and risk of incident ischemic heart disease, stroke, and diabetes: A systematic review and meta-analysis. Am J Clin Nutr,2014. 100(1): p. 278-88.3.
- Grosso, G., et al., Nut consumption on all-cause, cardiovascular, and cancer mortality risk: a systematic review and meta-analysis of epidemiologic studies. Am J Clin Nutr, 2015. 101(4): 783-93.
- Gervasi, T., et al., Health Benefits Related to Tree Nut Consumption and Their Bioactive Compounds. Int J Mol Sci, 2021. 22: 5960.
- Wu, L., et al., Nut consumption and risk of cancer and type 2 diabetes: a systematic review and meta-analysis. Nutr Rev, 2015. 73(7): 409-25.
- Neale, E., et al., The effect of nut consumption on heart health: an updated systematic review of the literature. 2018. Nuts for Life, unpublished.
- Australian Institute of Health and Welfare. Australian Burden of Disease Study 2015: Interactive data on risk factor burden. 2020, AIHW: Canberra.
- Nikodijevic CJ., et al. Nut consumption in a representative survey of Australians: A secondary analysis of the 2011–2012 National Nutrition and Physical Activity Survey. Public Health Nutr, 2020; 23(18).
- Australian Bureau of Statistics. National Health Survey – First results (released 2018). Available at: https://www.abs.gov.au/statistics/health/health-conditions-and-risks/national-health-survey-first-results/latest-release#health-risk-factors
- Willett, W., et al., Food in the Anthropocene: the EAT-Lancet Commission on healthy diets from sustainable food systems. The Lancet, 2019. 393(10170): 447-492.
- Kovacs B. et al., The carbon footprint of dietary guidelines around the world: A seven country modelling study. Nutrition Journal, 2021. 20(15).
- EAT-Lancet Commission Summary Report 2019. Available at: https://eatforum.org/eat-lancet-commission/eat-lancet-commission-summary-report/
- ASCIA. Guidelines: Infant feeding and allergy prevention. ASCIA 2020. http://www.allergy.org.au/patients/allergy-prevention/ascia-guidelines-for-infant-feeding-and-allergy-prevention
Published June 24, 2021