Finally, the news we’ve all been waiting to hear – eating pasta and bread does not contribute to weight gain

Recent ground-breaking research has finally dispelled the myth that eating grain foods causes weight gain and furthermore, suggests that grains are much more nutritious than most people think. The research comes from the Grains & Legumes Nutrition Council who conducted an analysis of the most recent National Nutrition Survey, which looked at the diets of over 9,000 adults (1). Results showed that consumption of core grain foods, including both white and wholegrain bread and pasta, was not linked to waist circumference or BMI.

A range of factors that can affect weight status were taken into account in the study, including physical activity levels and whether the study subject was on a diet with the data still showing that people eating six or more serves of core grain foods per day, have similar waistline measurements and BMI’s than those who restrict their grain intake.

Almost one in two Australians limit wheat and other grain foods due to this misperception that foods such as bread and pasta cause weight gain (2), so it’s no surprise that Australians are missing out on the additional health benefits of grain foods. This avoidance has been driven by the recent ‘gluten free’ and ‘free from’ trends, with 21% of people in the Asia-Pacific region stating that a gluten free label influences their purchasing behaviour (3).

In Australia in particular, this has led to a 30% reduction in the consumption of core grain foods over 2 years (2), due to a belief that grain foods, even high fibre grain foods such as whole grain bread and wholemeal pasta, have no place in a healthy diet. And young women are missing out the most, with just 8.5% of 19-50 year old females meeting core grain food recommendations (2).

There are many benefits to be had when consuming a diet rich in core grain foods, particularly whole grain and high fibre choices. Whole grain wheat and bran-based grain foods contain insoluble fibre which promotes regular digestive function alongside fermentable dietary fibre in grains which behave like prebiotics, encouraging the growth of beneficial bacteria in the digestive system. So grains are good for your gut health too!

In addition, those with higher intakes of whole grain and high fibre grain foods are less likely to gain weight over time (4&5), have heart disease (6&7), experience low grade inflammation (8-12), suffer an early death (13) and are more likely to report being in excellent health. By cutting out core grain foods believing it will keep them slim, people may be putting their health at risk. Find out more of the health benefits of whole grains here.

Michelle Broom, General Manager of the Grains & Legumes Nutrition Council, explains, “This new study adds to the evidence that core grain foods are an important  part of a healthy, balanced diet. By meeting the recommended six daily serves, at least half of which should be whole grain, we can enjoy the many benefits of core grain consumption, without any difference in BMI or waist circumference.”

It’s easy to get your recommended six serves a day; with 2 slices of whole grain toast for breakfast, a salad with a cup of quinoa for lunch and half a cup of pasta with a tomato sauce for dinner. For delicious ideas to up your grain intake, including this deliciously different Indian Spiced Millet Pilaf or a Quinoa & Wheat Berry Tabouleh visit the GLNC website.

For more information on the number of grain serves recommended for different age and gender groups download our factsheet.

References

1. Nutrition Research Australia. Secondary Analysis of the 2011-12 National Nutrition and Physical Activity Survey. Submitted for publication. 2015

2. Grains & Legumes Nutrition Council (GLNC). 2014 Australian Grains and Legumes Consumption & Attitudinal Report. Unpublished. 2014

3. The Nielsen Company. We Are What We Eat: Healthy Eating Trends Around the World. http://www.nielsen.com/content/dam/nielsenglobal/

4. Williams PG, Grafenauer SJ, O'Shea JE. Cereal Grains, Legumes, and Weight Management: A Comprehensive Review of the Ccientific Evidence. Nutrition Reviews. 2008;66(4):171-82.

5.  Mozaffarian D, Hao T, Rimm EB, Willett WC, Hu FB. Changes in Diet and Lifestyle and Long-Term Weight Gain in Women and Men. New England Journal of Medicine. 2011;364(25):2392-404.

6. Tang G, Wang D, Long J, Yang F, Si L. Meta-Analysis of the Association Between Whole Grain Intake and Coronary Heart Disease Risk. American Journal of Cardiology. 2015;115(5):625-9.

7. Barclay AW, Petocz P, McMillan-Price J, Flood VM, Prvan T, Mitchell P, et al. Glycemic Index, Glycemic Load, and Chronic Disease Risk—A Meta-Analysis of Observational Studies. The American Journal of Clinical Nutrition. 2008;87(3):627-37.

8. Lefevre M, Jonnalagadda S. Effect of Whole Grains on Markers of Subclinical Inflammation. Nutrition Reviews. 2012;70(7):387-96.

9. Galisteo M, Duarte J, Zarzuelo A. Effects of Dietary Fibers on Disturbances Clustered in the Metabolic Syndrome. Journal of Nutritional Biochemistry.19(2):71-84.

10. King DE, Mainous AG, Egan BM, Woolson RF, Geesey ME. Fiber and C-Reactive Protein in Diabetes, Hypertension, and Obesity. Diabetes Care. 2005;28(6):1487-9.

11.  King DE, Egan BM, Geesey ME. Relation of Dietary Fat and Fiber to Elevation of C-Reactive Protein. American Journal of Cardiology.92(11):1335-9.

12. Ajani UA, Ford ES, Mokdad AH. Dietary Fiber and C-Reactive Protein: Findings from National Health and Nutrition Examination Survey Data. The Journal of Nutrition. 2004;134(5):1181-5 13. Kim Y, Je Y. Dietary Fiber Intake and Total Mortality: A Meta-Analysis of Prospective Cohort Studies. American Journal of Epidemiology. 2014;180(6):565-73.

14. Grains & Legumes Nutrition Council (GLNC). GLNC Grains & Legumes Product Audit. Unpublished. 2015-16

Health Star Rating

The Health Star Rating (HSR) system, which rates foods from half-a-star to five stars based on nutritional value, was approved by the Federal and State Ministers in June 2013 and has been implemented since June 2014 on a voluntary basis by the food industry. Interestingly, the system is at odds with the Australian Dietary Guidelines in the exclusion of whole grains from the algorithm.

Currently, the nutritional value of a large number of whole grain foods is not accurately reflected in the HSR system due to the exclusion of whole grain from the algorithm to calculate the number of stars. In consultation with manufacturers, GLNC conducted an assessment of 285 grain-based foods on shelf in 2015 – 2016 which shows that the crude inclusion of whole grain in the HSR system algorithm would affect at least 76 products across a variety of categories. This represents one quarter of all grain foods assessed.

One argument against the inclusion of whole grain in the calculation of HSR ‘V’ points is that fibre may be considered a proxy measure for whole grain. However, the assessment of the number of products affected by the addition of whole grain to the calculation indicates this is not always true. 

GLNC understands that altering the algorithm to include whole grain may be more complex than the crude addition of a point. However, we believe the magnitude of the potential public health benefit warrants consideration of a change to the algorithm.

Only 30% of the grain food intake of Australian adults is whole grain, well short of the 66% recommended by the Australian Dietary Guidelines. By recognizing whole grain in the HSR system, this will encourage people to choose foods higher in whole grain more often which will promote increased whole grain consumption, reducing risk of chronic disease.

Adding whole grain to the HSR algorithm may encourage the development of foods with higher whole grain content. This is a positive change for the food supply. Currently, whole grain is used predominantly in core grain foods such as breakfast cereals and bread, but in a very limited capacity in discretionary foods such as biscuits. Any proposed change to the algorithm would need to assess the potential effect on the HSR of discretionary foods. However, it is unlikely large quantities of whole grain would be added to discretionary foods for reasons of increasing HSR status only as this raises functional issues. Manufacturers have found adding large quantities of the bran and germ content of whole grain wheat can have a detrimental effect on product quality and acceptability. 

As the HSR system evolves, consideration should be given to the significant public health benefit of potentially changing the algorithm to include whole grain.

Diet and the gut microbiota: what do we know?

By Rebecca Evans

Did you know there is a third wheel in everyone’s relationship between themselves and the food they eat? This third wheel is our gut microbiota; the unique ecosystem of microorganisms residing within our intestines. While many may think their relationship with food is exclusive, emerging research is revealing that what we eat may influence our gut microbiota, which could have potential health implications⁽¹⁾. Here we have summarised the latest evidence on the relationship between our gut microbiota, health and what we know about the role of diet in this.

Health and our gut microbiota

Current research on how the gut microbiota affects our health is limited. The research is based largely on observational studies, rather than clinical trials which are considered to be the gold standard for research. Current evidence suggests a healthy gut microbiota is associated with improved immunity, reduced risk of some cancers, lower inflammation, improved bone health, vitamin synthesis, weight management and improved laxation. Comparatively an unhealthy gut microbiota caused by a microbial imbalance, termed dysbiosis, is associated with overall overweight and obesity levels, insulin resistance, leptin (an appetite hormone) resistance, high cholesterol and increased inflammation^(1-4).  While this is an emerging area of research, at this stage, it is apparent our gut microbiota is linked with our health. But what affects our gut microbiota?  

Diet and the gut microbiota

Our gut microbiota is influenced by a number of factors including age, birth mode (vaginal versus caesarean), diet, stress, antibiotic use and genetics. Furthermore, diet also influences the gut microbiota and is a modifiable factor that you can change. While our current understanding on the role of diet is also limited to observational studies, a diet that contains a variety of fibre rich plant foods appears to have a beneficial effect on the gut microbiota⁽⁵⁾.

Dietary fibres, by definition are indigestible or resist digestion, and it is fibre which appears to play a starring role when it comes to promoting beneficial gut microbiota⁽⁵⁾. In particular prebiotics, a specific type of dietary fibre, can promote the growth and/or activity of beneficial bacteria in the gut. This is known as the “prebiotic effect”.

Just like we take in food and produce waste products, our microbiota do as well. Our gut microbiota produce short chain fatty acids i.e. acetate, propionate and butyrate from the prebiotics in our diets. Short chain fatty acids have beneficial effects on our health and are associated with a reduced risk of disease, including cancer^{(3, 6)}. Eating a variety of plant foods within a high fibre diet, including whole grain and high fibre grain foods, legumes, nuts, fruit and vegetables, will ensure a varied intake of prebiotic fibres⁽⁷⁾.

Probiotics

Probiotics are live microorganisms found in supplements and fermented foods^{(2, 5)}. When foods are fermented they are broken down into a simpler form by microorganisms such as yeast and bacteria⁽⁸⁾. Common fermented foods include sauerkraut (cabbage fermented with lactic acid bacteria) and yoghurt (milk fermented with lactic acid bacteria). However, what many people don’t realise is that the indigestible components of food (i.e. prebiotic fibre) actually undergoes fermentation by the gut microbiota which means fermented foods are fermented twice, once outside the body and again in the gut⁽⁸⁾.

It is possible to ferment pre-cooked grains and legumes by adding a starter culture such as whey or yoghurt⁽⁹⁾. This is usually preceded by soaking the legumes or grains in warm water in a warm place for 12 to 24 hours. Some common fermented grains and legumes include sourdough bread, miso and tempeh, which can be bought in many shops.

How to optimise your relationship with your gut microbiota

Our gut microbiota is as unique and individual as our finger prints. It’s time we recognised the third wheel between our health and diet. For many, the good news it is that it is never too late to work on the relationship with your gut microbiota. Research suggests that our gut microbiota composition can be altered through short term dietary intervention, as well as long term habitual dietary change^{(3, 10)}.

Early research suggests an optimal diet to promote beneficial gut microbiota is high in dietary fibre (prebiotics) from plant sources. This could be achieved by increasing your intake of vegetables, fruit, legumes and nuts, as well as whole grain and high fibre grain foods⁽⁶⁾. This is consistent with Australian Dietary Guidelines and GLNC’s recommendation for all Australians to enjoy grain foods 3-4 times a day, choosing at least half as whole grain or high fibre and to enjoy legumes at least 2-3 times a week.

For a range of fibre rich recipes, cooking tips and snack ideas with grains and legumes visit the GLNC website.

References

1.Flint HJ, Scott KP, Louis P, Duncan SH. The role of the gut microbiota in nutrition and health. Nat Rev Gastroenterol Hepatol. 2012;9(10):577-89.

2.Graf D, Di Cagno R, Fak F, Flint HJ, Nyman M, Saarela M, et al. Contribution of diet to the composition of the human gut microbiota. Microb Ecol Health Dis. 2015;26:26164.

3.Scott KP, Gratz SW, Sheridan PO, Flint HJ, Duncan SH. The influence of diet on the gut microbiota. Pharmacol Res. 2013;69(1):52-60.

4.Guarner F. The Gut Microbiome: What Do We Know? Clinical Liver Disease. 2015;5(4):86-90.

5.Slavin J. Fiber and prebiotics: mechanisms and health benefits. Nutrients. 2013;5(4):1417-35.

6.Bi Y, Qin N, Yang R. Human microbiota: a neglected "organ" in precision medicine. Infectious Diseases and Translational Medicine. 2015;1(2).

7.Halmos EP, Christophersen CT, Bird AR, Shepherd SJ, Gibson PR, Muir JG. Diets that differ in their FODMAP content alter the colonic luminal microenvironment. Gut. 2015;64(1):93-100.

8.Achi OK, Ukwuru M. Cereal-Based Fermented Foods of Africa as Functional Foods. International Journal of Microbiology and Application. 2015;2(4):71-83.

9.Pinkfarm. Traditional Preparation Methods of: grains, nuts, seeds and legumes n.d. [cited 2016 18th January]. Available from: http://www.pinkfarm.com.au/real-traditions/properly-prepared-grains-nuts-seeds/.

10.David LA, Maurice CF, Carmody RN, Gootenberg DB, Button JE, Wolfe BE, et al. Diet rapidly and reproducibly alters the human gut microbiome. Nature. 2014;505(7484):559-63.