Tuesday, June 5, 2012

Plant-based nutrition

Shifting to a more plant based diet

Dietary Guidelines around the globe recommend the inclusion of grain foods and legumes as part of a healthy diet. Despite this, there is a common belief that a diet including larger amounts of plant-based foods may not provide adequate nutrients. New Australian research has demonstrated that it is possible to achieve adequate nutrient intake on a diet that is dominated by whole grains, legumes, nuts, seeds, fruit and vegetables.

According to Dr Rosemary Stanton OAM, “Diets dominated by whole grains, legumes, nuts, seeds, fruits and vegetables are almost certainly the way of the future.” Dr Stanton is the editor of a supplement of peer-reviewed articles dedicated to plant-based nutrition was published this week with the Medical Journal of Australia (MJA). The Grains & Legumes Nutrition Council is pleased to be associated with this extensive review of the science demonstrating the contribution of plant-based foods to the Australian diet.

Comparisons of population intakes with dietary recommendations indicate that to meet dietary intakes people need to shift toward a more plant-based eating pattern. The recently published draft Australian Dietary Guidelines indicates that to satisfy recommended dietary intakes, adults need to increase grain foods in the diet by 30%, and in particular high-fibre and wholegrain products by 160%. In addition Australians would need to consume 40% more fish, poultry, seafood and eggs, or legumes / beans, nuts or seeds.

International recommendations also indicate a similar shift. At the recent Wholegrain Summit in the USA, Dr Eric Rimm from Harvard University and a member of the advisory committee for the US Dietary Guidelines, explained that one of the key principles of the 2010 Dietary Guidelines was to encourage a diet that includes more plant foods such as whole grains, legumes, nuts and fruit and vegetables.

The MJA supplement includes articles on the adequacy of a diet dominated by plant foods and highlights the contribution of plant foods such as grains and legumes to key nutrients in a healthy diet. Plant-based foods such as grains and legumes, along with nuts and seeds, are a source of a range of nutrients including protein, iron and zinc.

Plant foods contribute significantly to the protein intake in the Australian diet. While most grain and legume foods have limited amounts of some amino acids, the review found that a varied plant-based diet can easily meet protein requirements as long the diet meets energy needs.

A diet rich in whole grains, legumes, nuts, seeds, dried fruits, iron-fortified cereals and green leafy vegetables provides an adequate intake of iron. The paper in the MJA Supplement on iron requirements explains that this is because a person eating a more plant-based diet will adjust to absorb iron more readily. In fact, most of the iron in the Australian diet comes from plant foods.

Phytate is a known inhibitor of zinc absorption. However, the inhibition can be reduced by processes used to make or prepare most grain foods legumes such as soaking, heating, fermenting and leavening. Plant foods high in zinc include cooked brown rice (1.9mg in 1 cup), tofu (1.7mg/100g), and cashews (1.7g/30g handful).

This research demonstrates that it is possible to achieve adequate nutrient intake on a diet that is dominated by whole grains, legumes, nuts, seeds, fruits and vegetables. The Grains & Legumes Nutrition Council recommends Australians follow the Australian Dietary Guidelines and eat a variety of foods including high fibre and whole grain foods as well as legumes.

The 40 page supplement is available online via the MJAOPEN website www.mja.com.au/open.

National Health and Medical Research Council. Revised Draft for Public Consultation:

Australian Dietary Guidelines & Australian Guide to Healthy Eating. 2011, Commonwealth of Australia: Canberra

Grain foods for health

Working towards healthier grain foods for everyone

Public health as the key outcome of primary industry, a global definition for whole grain food, and ways to change consumers of health care into consumers of health. These were all hot topics of discussion at a recent global meeting of international leaders in the field of grain research, policy and communication. As scientists, policy makers, food manufacturers, health care professionals and interested individuals we all have a role to play.

Robyn Murray, CEO and Michelle Broom, Nutrition Manager
Grains & Legumes Nutrition Council attending the conference

In May the Grains and Legumes Nutrition Council partnered with a number of organisations from around the world for the 2012 Whole Grains Summit in Minnesota USA. The Summit brought together scientists as well as business and health professionals from around the globe working in the area of grains and grain foods to discuss how to improve the availability of healthier grain-based foods for everyone. Presentations ranged from breeding grains to improve nutritional benefit through to regulations and communication strategies to encourage the next generation to include more nutritious grain foods in their diet.

Dr Eric Rimm, from Harvard University and a member of the advisory committee for the US Dietary Guidelines, explained that one of the key principles of the 2010 Dietary Guidelines was to encourage a more plant-based diet. However, he stressed it is important that these are plant-based foods with high nutritional value.

At the first step, breeding, researchers are exploring ways to improve the nutrient quality of the grain we eat while also addressing the challenge of meeting the needs of an increasing global population. Current projects range from ultra low gluten barley to lower GI wheat as well as plant-based sources of EPA and DHA omega-3 fats. A number of speakers explained how flour millers and food manufacturers are working to ensure the integrity of this improved nutritional value is maintained through processing. However, John Finley, from the US Department of Agriculture, pointed out that the current focus for wheat breeding is productivity not health. He suggested that one way to change the paradigm to produce grains for health is to connect breeders and nutritionists.

Moving from grain to food, a key theme that emerged from the Summit was the need for a definition of a whole grain food. Several countries have a definition of ‘whole grain’ as containing the same fraction of endosperm, germ and bran. However, whole grain foods currently contain a broad range of whole grain content. For example bread may contain anything from 1 gram to 20 grams of whole grain per slice. It was agreed that a minimum whole grain content to call a food ‘whole grain’ would help not only people buying food but also researchers and policy makers. As 48g per day of whole grain has been adopted as a target intake in several countries, including Australia, it was suggested that a minimum of 8 g/serve would useful minimum. By having the recommended six serves of grain food with 8g of whole grain would allow a person to meet the 48g daily target.

To help change consumers of health care into consumers of health a number of speakers suggested we look to the next generation. A hangover from the recommendation for low fat, high fibre foods may be part of the problem when it comes to the idea many adults have that high fibre foods don’t taste good. A whole new generation may be more open to trying high fibre foods, made with good fats and so help the family make more nutritious grain choices. One way this is being attempted is by introducing whole grain-rich foods to school lunches across the US. Starting on July 1st 2013, all grain foods in school breakfasts and school lunches must be whole grain-rich.

It was agreed that a strategic approach is needed for research, policy, food manufacture and communication in the area of grain foods. From breeding better grains, producing a greater variety of good quality food choices through to helping people make those choices we all have a part to play in making nutritious foods more accessible for everyone.

For more information on the Summit visit http://www.cce.umn.edu/Whole-Grains-Summit-2012/\

Recordings and slides from a selection of the presentations will be available in the coming months on the Grains for Health Foundation website http://www.grainsforhealth.org/

Whole Grains Summit 2012. Whole Grains & Health from theory to practice. May 20-22, 2012. Minneapolis, MN USA. http://www.cce.umn.edu/Whole-Grains-Summit-2012/index.html