Barley FAQ-Health Professionals

Why Barley?

What is barley?

Barley (Hordeum vulgare) is an ancient cereal grain that has been grown and consumed for thousands of years. Barley is Canada’s fourth-largest crop, after wheat, canola and corn.1 In North America, barley is a major crop used for animal feed as well as for malt for brewing beer, but is also becoming increasingly popular as a healthy, locally produced grain.

 

What is a whole grain?

Whole grains contain all the essential parts and naturally occurring nutrients of the entire grain kernel in their original proportions. If the grain has been processed (e.g., cracked, crushed, rolled, milled), the product should deliver the same rich balance of nutrients that are found in the original kernel. This means that 100 per cent of the original kernel—all of the bran, germ and endosperm—must be present to qualify as a whole grain.

 

The outer bran layer of whole grains is composed of non-digestible, insoluble, minimally fermentable carbohydrates.2 The inner germ and endosperm contain viscous soluble fibres and many other nutrients.2 In addition to dietary fibre, whole grains are important sources of resistant starch, trace minerals, vitamins, phytoestrogens and antioxidants that are associated with disease prevention.

Where can I buy barley?

The various forms of barley can be purchased at most grocery and health food stores. Barley is often found in the bulk foods section or as a packaged product.

 

How do I incorporate barley into my diet?

Barley has a wonderful nutty flavour and appealing texture. Pearled barley can be easily incorporated into soups, salads and main course dishes, and can be cooked on the stovetop or in a rice cooker, oven or slow cooker. When cooking pearled barley, make some extra to use in other dishes; cooked barley can be frozen in an airtight container and kept for up to three months. Barley flour and barley flakes are other versatile options. Depending on the recipe, barley flour can completely or partially replace wheat flour in a recipe. Barley flakes can be consumed as a breakfast cereal or can replace oatmeal in baked goods such as cookies. For cooking instructions and recipe ideas, visit www.gobarley.com.

Benefits of Barley

What are the health benefits of barley?

The potential health benefits of barley are extensive. Barley has the highest fibre content of the cereal grains.3 Dietary fibre intake is inversely associated with risk of chronic disease, including coronary heart disease, stroke, hypertension, diabetes, obesity and metabolic syndrome.4 The fibre in barley helps lower cholesterol, a major risk factor for cardiovascular disease. Barley fibre expands and creates a viscous, gel-like substance in the gastrointestinal tract that helps increase satiety and thus aids in weight management. A daily intake of approximately three servings of whole grains is associated with lower body mass index and reduced central adiposity.2 Barley has the lowest glycemic index of the food grains. Low-glycemic-index foods may help in the treatment and prevention of diabetes.5,6

Barley also promotes gastrointestinal health since high-fibre foods are recommended for gastroesophageal reflux disease, duodenal ulcers, inflammatory bowel syndrome, diverticular disease, constipation and hemorrhoids.4 As the largest immune organ in the human body, the gastrointestinal tract is key to overall health, and high fibre intake may enhance the immune system.4

What types of barley are available and which is the healthiest?

Pearl and pot barley are the most common products available. Pot and pearl barley are processed by “pearling,” which removes the inedible hull and creates a white-coloured, quicker-cooking product. Besides removing the inedible outer hull, the pearling process removes the germ and bran layer and, for this reason, pot and pearl barley are not considered whole grains. They are, however, still high in protein and soluble fibre. The difference between pot and pearl barley is that pearl barley has been pearled more to produce a whiter product.

Whole barley that has been dehulled to remove the inedible hull is also available. Because only the inedible hull is removed, it is considered a whole grain. Whole barley takes longer to cook than either pearl or pot barley.

Barley flour milled from either pearled barley or whole, dehulled barley can be used as a complete or partial substitute for wheat flour in recipes. Barley flakes can be used as a breakfast cereal or as a substitute for oatmeal in baked goods such as cookies.

All of these forms of barley are healthy options and are included in the list of β-glucan sources under both Health Canada and U.S. Food and Drug Administration health claim guidelines. The nutrition profile of pearled barley, hulled barley and barley flour is shown in Table 1.

Table 1. Nutrition profile of pearled, hulled barley and barley flour*

Barley, pearled
(1/4 cup, 50g)
Barley, hulled**
(1/4 cup, 46g)
Barley, flour***
(1/4 cup, 37 g)
Energy (kcal) 176.0 162.8 127.8
Total fat (g) 0.6 1.1 0.6
Protein (g) 5.0 5.7 3.9
Carbohydrate (g) 38.9 33.8 27.6
Fibre (g) 7.8 8.0 3.7

*Adapted from the U.S. Department of Agriculture3
**Minimally processed to remove the hull
***Made from pearled barley

What is β-glucan?

β-glucan is a type of soluble fibre found in the cell wall of some cereal grains including barley and oats. β-glucans are a mixed group of non-starch polysaccharides consisting of D-glucose monomers linked by β-glycosidic bonds.7 The β-linkages in the polymer make β-glucan non-digestible by human digestive enzymes.7 Barley is one of the richest sources of β-glucan, and many of the health benefits of barley are attributable to its β-glucan content.

What are the health effects of β-glucan?

The health benefits of β-glucan are the most widely reported of all fibres. β-glucan delays gastric emptying, lowers serum cholesterol and moderates the postprandial glycemic response.7 These properties make β-glucan a beneficial dietary fibre in the fight against obesity, cardiovascular disease and diabetes. Barley β-glucan may also possess anti-cancer properties.7

Is barley a good choice for people trying to lose weight or prevent weight gain?

Yes. Barley’s high fibre content may assist with weight loss or prevention of weight gain. Since fibre is not enzymatically digested and absorbed, but instead undergoes various degrees of fermentation in the large intestine, it effectively lowers dietary energy density.10 Barley has the highest fibre content of whole grains.2 Soluble fibres, such as the β-glucan in barley, contribute to satiety by absorbing large amounts of water and forming a gel, thereby increasing stomach distention and slowing gastric emptying.10 Epidemiologic studies demonstrate that a daily intake of approximately three servings of whole grains is associated with a lower body mass index and a reduction in central adiposity.2 Dietary fibre from whole foods may promote weight loss at intakes of 20 to 27 grams per day.26

What is a prebiotic? Does barley contain prebiotics?

A complex community of bacteria lives in the human intestine. These bacteria play an important role in health and well-being. Intestinal microbiota regulate inflammatory responses and immune function, and may affect fat metabolism and the risk of Type 2 diabetes.27 Certain food components (prebiotics) promote the growth of the beneficial bacteria (probiotics) while inhibiting harmful bacteria. Together, prebiotics and probiotics are called synbiotics.

Prebiotics are non-digestible food components that selectively stimulate the activity of favourable intestinal bacteria and improve the health of the host.28 All prebiotics are fibre, but not all fibres are prebiotics.28 To be classified as a prebiotic, the food component cannot be digested by human enzymes or absorbed in the upper gastrointestinal tract, must be fermentable by the intestinal microflora, and must selectively stimulate the activity of intestinal bacteria that potentially promote health.28 Some of the health benefits of prebiotics may include:28

  • Reduced infectious and antibiotic-associated diarrhea;
  • Reduced inflammation and symptoms in people with inflammatory bowel disease;
  • Protection against colon cancer and cardiovascular disease;
  • Enhanced mineral absorption; and
  • Promotion of satiety and weight loss, and prevention of obesity.

Barley β-glucan has been shown to be highly fermentable and may possess prebiotic properties, though this research is in its early stages.

Gluten

Does barley contain gluten?

Yes. Celiac disease, or gluten-sensitive enteropathy, is an autoimmune disorder of the gastrointestinal tract. It affects approximately one in 133 people in Canada and requires individuals to consume a gluten-free diet. Some individuals may be sensitive to gluten but do not have celiac disease (non-celiac gluten sensitivity). These individuals cannot tolerate gluten and experience similar symptoms to those with celiac disease, but do not have the same antibodies and intestinal damage as celiac patients.

Gluten is a protein found in wheat (including spelt and kamut), barley, rye and triticale. Since barley contains gluten, people diagnosed with celiac disease or non-celiac gluten sensitivity need to avoid barley and barley-containing products.

Is celiac disease the same as wheat allergy?

Wheat allergy is not the same as celiac disease or gluten sensitivity.8 Wheat allergy is an adverse immunologic reaction that occurs in approximately 0.3 to three per cent of the population.8 People who are allergic to wheat may be able to tolerate other cereal grains such as barley. Although barley may be eliminated from meal planning when implementing a wheat-free diet, the health benefits of barley warrant experimentation with reintroduction under medical supervision.

Should individuals remove gluten from their diet if they want to lose weight?

No. There is limited research on the association between gluten and obesity. A gluten-free diet should not be self-prescribed without medical supervision. It is restrictive and difficult to follow, and can result in inadequate nutrient intakes. In addition, numerous studies suggest that fibre from whole grains supports weight management.9 Soluble fibres, such as the β-glucan in barley, contribute to satiety by absorbing large amounts of water, resulting in the formation of a gel, thereby increasing stomach distension and slowing gastric emptying.10 In addition, whole grains protect against cardiovascular disease by improving blood glucose control, reducing blood pressure and lowering cholesterol and high-sensitivity C-reactive protein levels.8

Health Claim

What are the health claims for barley?

In 2012, Health Canada approved the claim that barley-containing foods are a source of fibre shown to help lower cholesterol.11 An example of the permitted claim is: “125 millilitres of cooked pearled barley supplies 60 per cent of the daily amount of the fibre shown to help lower cholesterol.”11 The “daily amount” referred to in the claim is three grams of barley β-glucan.11 To be eligible to make the claim, the food must contain at least one gram of β-glucan per serving from dehulled or hulless barley, pearled barley, barley flakes, grits, meal, flour, bran or β-glucan-enriched milling fractions.11

Health Canada permits the following statements in addition to the primary statement:11

  • Barley fibre helps reduce/lower cholesterol
  • High cholesterol is a risk factor for heart disease
  • Barley fibre helps reduce/lower cholesterol, (which is) a risk factor for heart disease

The United States Food and Drug Administration approved a health claim for barley in 2006. The claim permits foods containing barley that provide at least 0.75 grams of soluble fibre per serving to state that they may help to reduce the risk of coronary heart disease.12 An example of the claim would be: “Soluble fibre from foods such as barley cereal, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease. A serving of barley cereal supplies from barley one gram of the three grams soluble fibre necessary per day to have this effect.” The amount of soluble fibre per RACC (reference amounts customarily consumed) must be declared in the nutrition label.

How much barley does one have to consume to ingest the amount of β-glucan that lowers cholesterol?

Consumption of at least three grams of β-glucan per day helps reduce cholesterol. The β-glucan content of barley can vary somewhat so it is important to read labels. As a guideline, one-quarter cup of uncooked pot or pearl barley (approximately one cup cooked) contains approximately 2.5 grams of β-glucan fibre.13,14

How does barley lower cholesterol?

It has been shown that barley β-glucan increases bile acid excretion by entrapping the acids in the viscous gastrointestinal contents or by directly binding to bile acids leading to fecal excretion. Since cholesterol is a substrate for bile acid synthesis, increased excretion results in reduced circulating cholesterol levels.15 Soluble fibre may also lower cholesterol levels due to fermentation in the large intestine. Fermentation decreases pH and increases microbial populations, resulting in enhanced production of short-chain fatty acids that inhibit cholesterol synthesis.16

How much fibre should one consume per day?

The Institute of Medicine has set the adequate intake (AI) for fibre at 14 grams per 1,000 kilocalories, or about 25 grams per day for women and 38 grams per day for men.17 In spite of the known benefits of fibre, 90 per cent of the U.S. population does not consume enough16 and average intake among Canadians is only about half the recommended amount.18

How does the fibre content of barley compare to other grains?

Barley has some of the highest fibre content of the food grains.3 The fibre content of barley and other grains is shown in Table 2.

Table 2. Total dietary fibre content of selected grains3

Whole grain (dry) Total dietary fibre (g/100 g)
Barley, pearled 15.6
Rye 15.1
Wheat 12.2
Oats 10.6
Buckwheat 10.0
Corn 7.3
Quinoa 7.0
Wild rice 6.2
Brown rice, long grain 3.5

Barley & Diabetes

What is glycemic index and glycemic load?

Glycemic index was developed to rank carbohydrate-containing foods based on their effect on postprandial glycemic response. To determine glycemic index, portions of a test food and control food (either white bread or glucose) are fed in amounts that provide equivalent amounts of available carbohydrate. Blood samples are taken at specific time intervals after the food is consumed. The area under the glycemic response curve is then determined for both the test and control foods. The glycemic index of the test food is calculated as a percentage of the mean glycemic response to the control food.19 Glycemic load is calculated by multiplying the glycemic index by the carbohydrate content of the food.

What is the glycemic index of barley and how does it compare to other high carbohydrate foods?

Barley has the lowest glycemic index of the food grains. Its glycemic index is also lower than many other commonly consumed high-carbohydrate foods (Table 3).

Table 3. Glycemic index of selected foods20

Food Item GI*
Barley 40
Lentils 41
Corn 75
Buckwheat 78
Couscous 93
Rice, brown 94
Bread 100
Millet 101
Potato 117

*Glycemic index determined using white bread as reference food in subjects with normal glucose tolerance

Is barley suitable for people with diabetes?

Yes. Barley is an excellent food to include as part of a healthy diet for people with diabetes. Barley aligns with the nutrition guidelines for the prevention and management of diabetes established by the Canadian and American diabetes associations.6,21 Barley is a rich source of soluble fibre in the form of β-glucan, which can slow gastric emptying, delay glucose absorption and improve postprandial glycemic response.22

Barley has the lowest glycemic index of the food grains (Table 3). The use of glycemic index and glycemic load may provide a modest additional benefit for people with diabetes over only considering total carbohydrate intake.6

What is metabolic syndrome?

Metabolic syndrome is a cluster of metabolic abnormalities, including abdominal obesity, elevated serum triglycerides, low HDL-cholesterol, elevated blood pressure and insulin resistance.23 Risk of Type 2 diabetes and cardiovascular disease are increased in individuals with metabolic syndrome. Whole-grain intake has been shown to be associated with decreased prevalence of metabolic syndrome.24 Barley consumption has been shown to prevent insulin resistance, a characteristic of metabolic syndrome and an important risk factor for diabetes.25

References

  1. Agriculture and Agri-Food Canada. 2014. Canada: Outlook for Principal Field Crops (2014-01-24). http://www.agr.gc.ca/eng/industry-markets-and-trade/statistics-and-market-information/by-product-sector/crops/crops-market-information-canadian-industry/canada-outlook-for-principal-field-crops/canada-outlook-for-principal-field-crops-2014-01-24/?id=1390926466193 Accessed March 11 2014.
  2. Jonnalagadda SS, et al. J Nutr 2011;141:1011S-1022S.
  3. U.S. Department of Agriculture. 2011. USDA National Nutrient Database for Standard Reference. http://ndb.nal.usda.gov/ Accessed February 2 2014.
  4. Anderson JW, et al. Nutr Rev 2009;67:188-205.
  5. Casiraghi MC, et al. J Am Coll Nutr 2006;25:313-320.
  6. Bantle JP, et al. Diabetes Care 2008;31 Suppl 1:S61-78.
  7. El Khoury D, et al. J Nutr Metab 2012;2012:851362.
  8. Brouns FJPH, et al. J Cereal Sci 2013;58:209-215.
  9. Clark MJ, et al. J Am Coll Nutr 2013;32:200-211.
  10. Howarth NC, et al. Nutr Rev 2001;59:129-139.
  11. Health Canada. 2012. Summary of Health Canada’s assessment of a health claim about barley products and blood cholesterol lowering. http://www.hc-sc.gc.ca/fn-an/alt_formats/pdf/label-etiquet/claims-reclam/assess-evalu/barley-orge-eng.pdf Accessed January 22 2014.
  12. U.S. Food and Drug Administration. 2006. FDA finalizes health claim associating consumption of barley products with reduction of risk of coronary heart disease. http://www.fda.gov/newsevents/newsroom/pressannouncements/2006/ucm108657.htm Accessed January 20 2014.
  13. Ames NP, et al. J Nutr 2008;138:1237S-1243S.
  14. National Barley Foods Council. Barley facts: FDA health claim. http://www.barleyfoods.org/BarleyFacts-FDA.pdf Accessed February 3 2014.
  15. Lia A, et al. Am J Clin Nutr 1995;62:1245-1251.
  16. Bernstein AM, et al. Nutrients 2013;5:1471-1487.
  17. Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). Washington, D.C.: National Academy Press, 2005.
  18. Langlois K, et al. Health Rep 2009;20:11-20.
  19. Wolever TM, et al. Am J Clin Nutr 1991;54:846-854.
  20. Atkinson FS, et al. Diabetes Care 2008;31:2281-2283.
  21. Canadian Diabetes Association. Can J Diabetes 2008;32.
  22. Biorklund M, et al. Eur J Clin Nutr 2005;59:1272-1281.
  23. Johnson RJ, et al. Obesity (Silver Spring) 2013;21:659-664.
  24. McKeown NM, et al. Diabetes Care 2004;27:538-546.
  25. Kim H, et al. Eur J Nutr 2009;48:170-175.
  26. Slavin JL. J Am Diet Assoc 2008;108:1716-1731.
  27. Petschow B, et al. Ann N Y Acad Sci 2013;1306:1-17.
  28. Slavin J. Nutrients 2013;5:1417-1435.