Grains are the seeds of cereal crops such as wheat, rye, rice, oats and barley and have been a staple food for humans for thousands of years. In pre-industrial times grains were commonly eaten whole but advances in the milling and processing of grains allowed large-scale separation and removal of the bran and germ, resulting in refined flour that consists mainly of the starchy endosperm. Refined flour became popular because it produced baked goods with a softer texture and extended freshness. However the bran and germ contain a host of important nutrients, which are lost when the grain is refined.
Nowadays it is increasingly recognised that foods made with whole grain can make an important contribution to our health and wellbeing and that the whole grain ‘package’ provides benefits relating to the individual nutrients they contain. Research consistently shows that regular consumption of whole grain foods as part of a healthy diet can reduce the risk of heart disease, certain types of cancer, type 2 diabetes, and may also help in weight management.
What does whole grain mean?
Each cereal grain is made up of three distinct sections: the outer fibre-rich bran, the inner micronutrient-rich germ and the starchy main ‘body’ of the kernel known as the endosperm. Whole grain means that all three sections of the kernel are included and they can be eaten whole, cracked, split, flaked, or ground. Most often whole grains are milled into flour and used to make breads, cereals, pasta, crackers, and other grain-based foods. Regardless of how the grain is handled, a whole grain food product must deliver approximately the same relative proportions of bran, germ, and endosperm found in the original grain.1
Anatomy of a Whole Grain Kernel
Bran: The multi-layered outer skin of the kernel that helps to protect the other two parts of the kernel from sunlight, pests, water, and disease. It contains fibre, important antioxidants, iron, zinc, copper, magnesium, B vitamins, and phytonutrients.
Germ: The embryo which, if fertilised by pollen, will sprout into a new plant. It contains B vitamins, vitamin E, antioxidants, phytonutrients, and unsaturated fats.
Endosperm: The germ's food supply, which, if the grain were allowed to grow would provide essential energy to the young plant. As the largest portion of the kernel, the endosperm contains starchy carbohydrates, proteins, and small amounts of vitamins and minerals.
A whole grain can be a food on its own, such as oatmeal, brown rice, barley, or popcorn, or used as an ingredient in food, such as whole-wheat flour in bread or cereal. Types of whole grains include whole wheat, whole oats/oatmeal, whole grain cornmeal, popcorn, brown rice, whole rye, whole-grain barley, wild rice, buckwheat, triticale, bulgur (cracked wheat), millet, quinoa, and sorghum. Other less common whole grains include amaranth, emmer, farro, grano (lightly pearled wheat), spelt, and wheat berries.
Intake of whole grains
Research suggests that health benefits can be obtained at relatively low levels of whole grain consumption, typically one to three servings per day, however it seems that many people do not reach this level. Some of the specific barriers to whole grain consumption include the lack of knowledge as to what a whole grain is, the lack of awareness of its health benefits, the difficulties some consumers have identifying whole grain foods, the perception of the taste and flavour of these products, as well as their cost.2
In the UK about a third of adults and 27% of children do not consume any whole grain at all and only 5-6% of the population achieve three portions per day.3,4 This is similar to intakes in the US where according to a recent report of the Department of Agriculture (USDA), only 7% of Americans achieved three whole grain portions a day.5
By contrast to the USA and UK, Scandinavians tend to have higher intakes of whole grain mainly due to their reliance on whole-grain rye bread as a staple food. Due to differences in measurement it is difficult to compare studies but data suggest that intakes in Norway are four times greater than in the UK, and in Finland intakes are even higher. Men seem to consume more whole grain than women but this may simply be because of a greater food intake overall. In the UK higher levels of education and income are linked with a greater intake of whole grain, whereas in Finland the highest intakes of rye bread were observed in the lower social grades.3
Not just the fibre
Whole grain is rich in fibre, and although the benefits of fibre for gut and heart health have been known for some time, it seems that whole grain provides protection over and above that provided by the fibre. Studies show that in women, the health effects of whole grain on heart disease go beyond those linked to the fibre, whereas in men, the bran or fibre component of whole grains provided a significant portion of the protection.6,7
The health advantages of whole grains are largely associated with consuming the entire whole-grain “package,” which includes vitamins (B vitamins, vitamin E), minerals (iron, magnesium, zinc, potassium, selenium), essential fatty acids, phytochemicals (physiologically active components of plants that have functional health benefits) and other bioactive food components. Most of the health-promoting substances are found in the germ and bran of a grain kernel and include resistant starch, oligosaccharides, inulin, lignans, phytosterols, phytic acid, tannins, lipids, and antioxidants, such as phenolic acids and flavonoids.8 It is believed that these nutrients and other compounds, when consumed together, have an additive and synergistic effect on health.9
Recommendations for cereal grain consumption
Cereal grains are a good source of carbohydrates and fibre and national dietary guidelines have always encouraged the consumption of starchy and fibre-rich foods, but it is only recently that scientific knowledge has evolved to consider whole grains worth a separate mention from other refined cereals. Dietary guidelines around the world give recommendations for a healthy balanced diet and emphasise the importance of grain foods, particularly whole grains in the diet.
- In the UK the Balance of Good Health is a pictorial representation of the recommended balance of foods in the diet and aims to help people understand and enjoy healthy eating. The plate recommends that people “base a third of their food intake around the bread, cereals and potatoes group, aiming to include one food from this group at each meal” (British Nutrition Foundation), and “to eat wholemeal, whole grain, brown or high fibre versions where possible” (Food Standards Agency).10
- The dietary recommendations of Germany, Austria and Switzerland suggest five servings of cereals, cereal products and potatoes a day, preferably whole grain products.11
- In the USA the Dietary Guidelines for Americans, give advice on food and physical activity choices for health (www.healthierus.gov/dietaryguidelines). The guidelines were updated in 2005 and emphasise whole-grain foods including the recommendation to “make half your grains whole”. To help consumers choose a balanced diet the guidelines quantify the amount of whole-grain foods consumers should aim to eat each day as 3 or more ounce equivalents. To help consumers put the dietary guidelines into practice the USDA developed the Food Guide Pyramid.12 (supported by the website www.mypyramid.gov)
- A similar plate is used in the Dietary Guidelines for Australians. The guidelines emphasise the importance of cereals as “the foundation of our daily meals” and recommend between 6 to 12 servings of grain-based foods per day including plenty of whole grain varieties.13
- The Canadian Food Guide to Healthy Eating recommends 5-8 servings of grain products per day and advises to make at least half of the grain products consumed each day, whole grain.14
- In Greece, dietary guidelines recommend 8 servings of non refined cereal products and emphasise whole grain varieties.15
- There has also been a recent recommendation for 4 servings of whole grain per day in Denmark.16
How to recognise whole grain foods?
It might seem simple to find whole grain products, but just because it is brown or states that it is high in fibre does not necessarily mean it is whole grain. Additional label reading is required to correctly identify foods that qualify as whole grain.
To verify that a product is whole grain, consumers should be encouraged to look beyond a product’s name. Descriptive words in the product's name, such as stone-ground, multi-grain, 100% wheat, or bran, do not necessarily indicate that a product is whole grain. As a general guide it is necessary to look out for the word ‘whole’ as in “wholemeal”, “whole grain” or “100% whole wheat”on the packaging.
The ingredient statement will list whole grains by the specific grain, such as whole-wheat flour, whole oats, or whole-grain corn. In many whole-grain foods, a whole grain is among the first ingredients listed. Where foods have been made with several different whole grains these may be noted further down on the list of ingredients but may also qualify as a whole-grain food. However, the ingredient list does not clearly indicate the amount of whole grain present in the food, nor does whole grain appear on the nutrition information panel on packs.
Colour and Texture:
The brown colour of a food does not determine whole grain (e.g. some breads may be brown because molasses or caramel colouring have been added). Many whole-grain products, such as cereals, are light in colour. Also, whole-grain foods are not always dry or gritty, some may be dense with a pleasant “nutty” flavour or light and flaky like a cereal grain.
Just because a product is high in fibre does not automatically mean it is whole grain. On the other hand, the fibre content of a whole grain food varies depending on the type of grain, amount of bran, density of the product, and moisture content. Food enriched with wheat or oat bran may be high in fibre but does not necessarily contain the whole grain.
Health claims are only allowed where there is adequate scientific evidence. They are designed to help educate consumers and encourage consumption of healthier foods. To ensure harmonisation of health claims across Europe, EU Regulation 1924/2006, Nutrition and Health Claims made on Foods, came into force on 1st July 2007. The European Commission and Member States acting together will authorise health claims for use. They will be advised by the European Food Safety Authority (EFSA), which assumes responsibility for the assessment of claims.17
However local health claims will remain valid until full EU integration in 2010. For example UK products composed of 51% or more whole grain can claim ‘People with a healthy heart tend to eat more whole grain foods as part of a healthy lifestyle’.18 In Sweden products with at least 50% whole grain can state ‘A healthy lifestyle and a balanced diet rich in whole grain products reduce the risk of heart disease. Product X is rich in whole grains’.19
Innovations in the food supply
A recent pan-European study conducted by the European Food Information Council (EUFIC) on consumers nutrition knowledge shows that in the UK, Sweden, Hungary, Germany and Poland over 73% of the respondents knew experts recommend to eat more whole grain, with only 49% in France.20 Other consumer research conducted by the International Food Information Council (IFIC) shows that consumers that are aware of whole grain, are increasingly interested in consuming more whole-grain foods (78%).21
Food manufacturers can help by creating new products and reformulating existing products to contain increased levels of whole grains.
Some whole-grain products are being made with "white wheat flour", which comes from a naturally occurring albino variety of wheat. White wheat flour has a mild, sweet flavour more similar to that of a refined grain than a whole grain and resembles typical refined flour, but it has the nutritional value and fibre content of whole grain. This can increase the acceptance of the products made with such flour. However, white wheat does not contain tannins and phenolic acids, compounds found in the outer bran of the red wheat commonly used to make whole-wheat flour.
Another wheat flour offers the nutritional benefits of 100% whole wheat, yet functions and tastes like refined white flour. This flour is produced by a patented milling technique applied to traditional hard spring wheat, which preserves the mild flavour, colour, and texture of refined flour.
The HEALTHGRAIN project (Exploiting Bioactivity of European Cereal Grains for Improved Nutrition and Health Benefits), is looking to improve the well-being and reduce the risk of metabolic syndrome-related diseases in Europe by increasing the intake of protective compounds in whole grains. The project is developing new methods to incorporate grain-based concentrates and ingredients with high nutritional impact into consumer products with sensory quality appealing to European consumers, such as whole meal flours with diminished levels of fractions with less beneficial nutritional properties, ingredients with different compositions in terms of fibre, micronutrients and phytochemicals and products for individuals sensitive to wheat gluten.2
Other traditional whole grains, such as oats and barley, are gaining popularity with consumers. Whole-grain barley, wheat and rice are also now available in quick-cooking varieties (for wheat and rice, pre-cooked varieties that can be prepared in a few minutes in the microwave). Other innovative grain products have additional beneficial ingredients including oat-based products fortified with omega-3 fatty acids and vitamin E, and enriched pasta made with wheat, oats, spelt, legumes, and flaxseed.
Health effects of whole grains
Research demonstrates an association between consuming whole grain as part of a low-fat diet and a reduced risk of heart disease. Studies have consistently found that individuals taking three or more servings of whole grain foods per day have a 20 to 30 percent lower risk of cardiovascular events compared to individuals with lower intakes of whole grain.6,7, 22-24 This level of protection is not seen with refined grains and is even greater than that seen with fruit and vegetables.25
Potential mechanisms for this health effect have been proposed, but are not fully understood. Components of some whole grains, including soluble fibre, beta-glucan, alpha-tocotrienol, and the arginine-lysine ratio, are believed to play a role in lowering blood cholesterol. Whole grains may decrease risk of heart disease through their antioxidant content. Oxidative stress and inflammation are predominant pathological factors for several major diseases and it has been suggested that the variety of phytochemicals found in whole grains may directly or indirectly inhibit oxidative stress and inflammation.26 Other bioactive components are believed to play a role in vascular reactivity, clotting, and insulin sensitivity.27-29 Studies have not isolated the exact mechanisms for the positive effect of whole grain on cardiovascular health and it is likely that (as for fruit and vegetables) the whole grain ‘package’ is more protective than its individual components.8
Whole grains appear to be associated, in a number of studies, with a reduced risk of several gastrointestinal cancers. A review of 40 studies on gastrointestinal cancers found a 21 to 43 percent lower cancer risk with high intake of whole grains compared to low intakes.8 In recent large prospective cohort studies, whole grain consumption was associated with a modest reduced risk of colorectal cancer.27,30,31 The studies examining the risk of hormone-dependent cancers are limited.
Several mechanisms have been proposed for this action. Fibre and certain starches found in whole grains ferment in the colon to help reduce transit time and improve gastrointestinal health. Whole grain also contains antioxidants that may help protect against oxidative damage, which may play a role in cancer development. Other bioactive components in whole grain may affect hormone levels and possibly lower the risk of hormone-dependent cancers. Other potential mechanisms could be alterations in blood glucose levels and weight loss.8
However, a recent report published jointly by the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) reviewed existing studies on the relative risk of different types of cancer through lifestyle choices. It concluded that dietary fibre probably protects against colorectal cancer, but there is limited evidence suggesting that such foods protect against oesophageal cancer. The report did not find supportive data to conclude that the degree of refinement may be a factor modifying cancer risk, but acknowledged the difficulty in assessing whole grain intake in the absence of an internationally accepted definition, and the possible confounding between dietary fibre and other dietary constituents and in general with ”healthier” dietary patterns and lifestyles.32
Components of whole grain, including fibre, resistant starch, and oligosaccharides play roles in supporting gastrointestinal health. Studies suggest that dietary fibre from whole grain increases stool weight by absorbing water and the partial fermentation of fibre and oligosaccharides, which increases the amount of beneficial bacteria in stool.8,33 Resistant starch is not digested and absorbed like ordinary starch, which means it passes into the large intestine and behaves in a similar way to fibre. This larger and softer mass of residue speeds the movement of the bowel contents towards excretion. The effect of promoting normal intestinal regularity makes whole grain products integral components of diet plans to help alleviate constipation and decrease the risk of developing diverticulosis and diverticulitis.34
Major epidemiological studies show a reduced risk of 20 to 30 percent for type 2 diabetes associated with higher intakes of whole grain or cereal fibre.35 Evidence from observational studies and clinical trials suggests improved blood glucose control in people with diabetes and, in non-diabetic individuals, whole grains may lower fasting insulin levels and decrease insulin resistance.8,35 Whole grain intake is inversely associated with the risk of type 2 diabetes, and this association is stronger for the bran than for the germ. Findings from prospective cohort studies consistently support increasing whole grain consumption for the prevention of type 2 diabetes.36,37 Components of whole grain, including magnesium, fibre, vitamin E, phytic acids, lectins, and phenolic compounds, are believed to contribute to risk reduction of type 2 diabetes as well as lowering blood glucose and blood insulin levels. In studies that examined the source of fibre, researchers found that fibre from whole grain, but not from fruit or vegetable sources, appears to exert the protective effect in reducing risk for developing type 2 diabetes.37-39 A recent Cochrane review on the preventive effects of whole-grain foods on diabetes mellitus shows that the beneficial effects of whole grain are mainly explained via their effects on BMI and that the current evidence does not allow to draw a definite conclusion about the preventive effect of whole-grain foods on the development of type 2 diabetes and that properly designed long-term randomised controlled trials are needed.40
Emerging evidence suggests that whole grain intake may contribute to achieving and maintaining a healthy weight. Studies show that people who include whole grain as part of a healthful diet are less likely to gain weight over time.41,42 Eating a diet high in whole grains is associated with lower body mass index and weight, smaller waist circumference, and reduced risk of being overweight.43-45 People who consume more whole grains are likely to have healthier lifestyles.46
The mechanisms by which whole grain may support weight management include enhanced and extended satiation (regulation of energy intake per eating occasion to lower daily energy intake), and prolonged gastric emptying to delay the return of hunger.8
Although preliminary evidence suggests that whole grain may influence body-weight regulation, additional epidemiological studies and clinical trials are needed. The HEALTHGRAIN project, which will finish in 2010, is studying the mechanisms responsible for the health benefits of whole grain products on risk factors for cardiovascular disease, type 2 diabetes and overweight.2
How to eat more whole grains
To reap the many health benefits of whole grains it is advisable to eat 3 portions a day. It is easy to include whole grain in the diet simply by swapping some portions of refined starchy staples for whole grain varieties. Scientific studies support the recommendation of at least 48 g of whole grain daily. Increasing the consumption of whole grain should be done progressively to let the body adapt to higher fibre content.
In the serving examples of whole grain, foods do not need to contain 100% whole grain, but do need to contain a minimum of 51% whole grain to be called whole grain, and also contain the three components of whole grain – endosperm, germ and bran. See Table below for suggestions of whole grain choices.
Type of Food
Whole grain option
Porridge made with rolled oats or oatmeal
Puffed whole grains
Whole-grain muesli and cereal bars
Bread and crackers
Rye bread (pumpernickel), wholemeal, granary, wheatgerm or mixed grain breads.
Whole-wheat crackers, rye crackers and crispbreads
Whole-grain rice cakes
Wholemeal flour, wheat germ, buckwheat flour, unrefined rye and barley flour, oatmeal and oat flour
Brown rice, whole-wheat pasta, whole barley, bulgur wheat (cracked wheat) quinoa, pearl barley
Whole grain contains many healthful components, including dietary fibre, starch, essential fatty acids, antioxidants, vitamins, minerals, lignans, and phenolic compounds, that have been linked to reduced risk of heart disease, cancer, diabetes, and other chronic diseases. Since most of the health-promoting components are found in the germ and bran, foods made with whole grain can play an important role in maintaining good health. Eating more whole grain involves making relatively easy changes in grain food selections. With awareness and education, along with increased availability of easy-to-identify whole-grain products, consumers can increase their intake of whole grain to recommended levels.
What is a serving size or a portion of whole grains?
120g cooked brown rice or other cooked grain
120g cooked 100% whole-grain pasta
120g cooked hot cereal, such as oatmeal
30g uncooked whole-grain pasta, brown rice or other grain
1 slice 100% whole-grain bread
1 very small (30g) 100% whole-grain muffin
120g 100% whole-grain ready-to-eat cereal
- US Food and Drug Administration. FDA Provides Guidance on 'Whole Grain' for Manufacturers (Available at: http://www.fda.gov/bbs/topics/news/2006/NEW01317.html)
- The HEALTHGRAIN project (Exploiting Bioactivity of European Cereal Grains for Improved Nutrition and Health Benefits), funded by the European Community Sixth Framework Programme, 2005-2010 FOOD-CT-2005-514008
- Lang R, Jebb SA. Who consumes whole grains, and how much? Proceedings of the Nutrition Society 2003:62:123-127
- Thane CW, Jones AR, Stephen AM, Seal CJ, Jebb SA. Whole-grain intake of British young people aged 4-18. British Journal of Nutrition 2005:94(5):825-831
- Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Data. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 1999-2002
- Liu S, Stampfer MJ, Hu FB, Giovannucci E, Rimm E, Manson JE, Hennekens CH, Willett WC. Whole-grain consumption and risk of coronary heart disease: results from the Nurses’ Health Study. American Journal of Clinical Nutrition 1999;70(3):412-9
- Jensen MK, Koh-Banarjee P, Hu FB, Franz MJ, Sampson L, Gronbaek M, Rimm EB. Intake of whole grains, bran, and germ risk of coronary heart disease among men. American Journal of Clinical Nutrition 2004 Dec;80(6):1492-9
- Slavin J. Whole grains and human health. Nutrition Research Review 2004;17:99-110
- Pereira MA, Pins JJ, Jacobs DR, Marquart L, Keenan JM. Whole grains, cereal fiber, and chronic diseases: Epidemiologic evidence. In CRC Handbook of Dietary Fiber in Human Nutrition. Boca Raton, FL: CRC Press; 1993:461-479
- UK Food Standards Agency Health Eating Nutrition Essentials. Available at: www.eatwell.gov.uk/healthydiet/nutritionessentials
- The Food Pyramid for Germany, Austria and Switzerland. Available at: www.dge.de/pyramide/pyramide.html
- U.S. Department of Health and Human Services and U.S. Department of Agriculture. Dietary Guidelines for Americans, 2005. 6th edition, Washington DC: U.S. Govt Printing Office, Jan 2005. http://www.healthierus.gov/dietaryguidelines
- Australian Government, National Health and Medical Research Council. Guidelines for all Australians 2003. Available at: www.nhmrc.gov.au/publications/synopses/dietsyn.htm
- Health Canada Food Guide. 2007 (Available at: www.healthcanada.gc.ca/foodguide, accessed December 2008 or download pdf at http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/index-eng.php)
- Ministry of Health and Welfare, Supreme Scientific Health Council. Dietary guidelines for adults in Greece, 1999 (Available at http://www.mednet.gr/archives/1999-5/pdf/516.pdf accessed December 2008)
- National Food Institute, Technical University of Denmark. Wholegrain – Definition and scientific background for recommendations of wholegrain intake in Denmark. May 2008. http://www.food.dtu.dk/
- Regulation (EC) No 1924/2006 of the European Parliament and of the Council of 20 December 2006 on nutrition and health claims made on foods. Available at: www.eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2006:404:SOM:EN:HTML
- UK Joint Health Claims Initiative (health claims valid until 2010). (Available at: http://www.jhci.co.uk/)
- Swedish Nutrition Foundation health claims. (Available at: www.snf.ideon.se/snf/en/rh/Healh_claims_FF.htm)
- The European Food Information Council (EUFIC). Pan-European consumer research on in-store behaviour, understanding and use of nutrition information on food labels, combined with assessing nutrition knowledge (Available through webinar at http://www.focusbiz.co.uk/webinars/eufic/paneuropeanlabelresearch/europe/)
- The International Food Information Council Foundation. Food & Health Survey: Consumer Attitudes toward Food, Nutrition and Health. 2008:1-54. (Available at: http://ific.org/research/foodandhealthsurvey.cfm)
- Jensen MK, Koh-Banerjee P, Hu FB, Franz M, Sampson L, Grønbæk M and Rimm EB. Intakes of whole grains, bran, and germ and the risk of coronary heart disease in men. American Journal of Clinical Nutrition December 2004 Vol. 80, No. 6, 1492-1499
- Jacobs DRJ, Meyer KA, Kushi LH, Folsom AR. Is whole grain intake associated with reduced total and cause-specific death rates in older women? The Iowa Women’s Health Study. American Journal of Public Health 1999;89:322
- Pietinen P, Rimm EB, Korhonen P. Intake of dietary fiber and risk of coronary heart disease in a cohort of Finnish men: The alpha-tocopherol, beta-carotene cancer prevention study. Circulation 1996;94:2720-2727
- Steffen LM, Jacobs DRJ, Stevens J. Associations of whole-grain, refined-grain, and fruit and vegetable consumption with risks of all-cause mortality and incident coronary artery disease and ischemic stroke: the Atherosclerosis Risk in Communities (ARIC) Study. American Journal of Clinical Nutrition 2003;78:383-390
- Mellen PB, Walsh TF, Herrington DM. Whole grain intake and cardiovascular disease: a meta-analysis. Nutrition Metabolism and Cardiovascular Disease 2007:Epub ahead of print
- Jacobs DR, Andersen LF, Blomhoff R. Whole grain consumption is associated with a reduced risk of noncardiovascular, noncancer death attributed to inflammatory diseases in the Iowa Women’s Health Study American Journal of Clinical Nutrition 2007: 85(6):1606-1614
- Pereira MA, Jacobs DR, Pins JJ, Raatz S, Gross M, Slavin J, Seaquist E. The effect of whole grains on inflammation and fibrinolysis: a controlled feeding study. Circulation 2000:101:711
- Liese AD, Roach AK, Sparks KC, Marquart L, D’Agostino RB, Mayer-Davis EJ. Whole-grain intake and insulin sensitivity: the Insulin Resistance Atherosclerosis Study. American Journal of Clinical Nutrition 2003;78:965-71
- Schatzkin A, Mouw T, Park Y, Subar AF, Kipnis V, Hollenbeck A, Leitzmann MF and Thompson FE. Dietary fiber and whole-grain consumption in relation to colorectal cancer in the NIH-AARP Diet and Health Study. American Journal of Clinical Nutrition May 2007 Vol. 85, No. 5, 1353-1360
- Larsson SC, Giovannucci E, Bergkvist L and Wolk A. Whole grain consumption and risk of colorectal cancer: a population-based cohort of 60 000 women. British Journal of Cancer 2005: 92, 1803–1807
- WCRF/AICR (2007). Food, Nutrition, Physical Activity and the Prevention of Cancer – a Global Perspective. Washington D.C. (Available from http://www.dietandcancerreport.org/)
- Kurasawa S, Haack VS, Marlett JA. Plant residue and bacteria as bases for increased stool weight accompanying consumption of higher dietary fiber diets. Journal of the American College of Nutrition 2000; 19:426-433
- Marlett JA, McBurney MI, Slavin J. Position of the American Dietetic Association: health implications of dietary fiber. Journal of the American Dietetic Association 2002;102:993-1000
- Murtaugh MA, Jacobs DRJ, Jacob B, Steffen LM, Marquart L. Epidemiological support for the protection of whole grains against diabetes. Proceedings of the Nutrition Society 2003;62:143-149
- Munter JSL, Hu FB, Spiegelman D, Franz M, van Dam RM. Whole grain, bran, and germ intake and risk of type 2 diabetes: a prospective cohort study and systematic review. PloS Medicine 2007;4(8):e261
- Montonen J, Knekt P, Jarvinen R, Arommaa A, Reunanen A. Whole-grain and fiber intake and the incidence of type 2 diabetes. Journal of the American College of Nutrition 2003;77:622-629
- Hu FB, Manson JE, Stampfer MJ. Diet, lifestyle, and the risk of type 2 diabetes mellitus in women. New England Journal of Medicine 2001;345:790-797
- Salmeron J, Manson JE, Stampfer MJ, Colditz GA, Wing AL, Willett WC. Dietary fiber, glycemic load, and risk of noninsulin-dependent diabetes mellitus in women. Journal of American Medical Association 1997;277:472-477
- Priebe MG, van Binsbergen JJ, de Vos R, Vonk RJ. Whole grain foods for the prevention of type 2 diabetes mellitus. Cochrane Database Systematic Reviews 2008;23:CD006061
- Koh-Banerjee P, Rimm EB. Whole-grain consumption and weight gain: a review of the epidemiological evidence, potential mechanisms and opportunities for future research. Proceedings of the Nutrition Society 2003;62:25-29
- Koh-Banerjee P, Franz M, Sampson L, Liu S, Jacobs DRJ, Spiegelman D, Willett W, Rimm E. Changes in whole-grain, bran, and cereal fiber consumption in relation to 8-y weight gain among men. American Journal of Clinical Nutrition 2004;80:1237-45
- Newby PK, Maras J, Bakun P, Muller D, Ferrucci L and Tucker KL. Intake of whole grains, refined grains, and cereal fiber measured with 7-d diet records and associations with risk factors for chronic disease. American Journal of Clinical Nutrition Dec 2007;86(6):1745-1753
- Good CK, Holschuh N, Albertson AN, Eldridge AL. Whole Grain Consumption and Body Mass Index in Adult Women: An Analysis of NHANES 1999-2000 and the USDA Pyramid Servings Database. Journal of American College of Nutrition 2008 Vol 27(1):80-87
- Williams PG, Grafenauer SJ, O’Shea JE. Cereal grains, legumes, and weight management: a comprehensive review of the scientific evidence. Nutrition Reviews 2004 Vol. 66(4):171–182
- Harland JI, Garton LE. Whole-grain intake as a marker of healthy body weight and adiposity. Public Health Nutrition 2008 Jun;11(6):554-63