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Barley for Food and Health: Science, Technology, and Products

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182 HEALTH BENEFITS OF BARLEY FOODS<br />

particles. In the present study, the mean number of LDL particles decreased after<br />

all experimental diets, <strong>and</strong> the greatest decrease occurred after the high-soluble<br />

fiber diet. This same research group conducted a similar study with hypercholesterolemic<br />

men <strong>and</strong> women, both pre- <strong>and</strong> postmenopausal, who consumed barley<br />

(Behall et al. 2004b). Diets in this second study were calculated on the basis of<br />

β-glucan levels, containing 0, 3, <strong>and</strong> 6 g per day from barley foods. After five<br />

weeks cholesterol was significantly lower in subjects when the diet contained 3 or<br />

6gofβ-glucan, <strong>and</strong> the greatest change occurred in the men <strong>and</strong> postmenopausal<br />

women. Contrary to the previous experiment, HDL cholesterol <strong>and</strong> triglycerides<br />

did not differ in subjects consuming any level of β-glucan. In this study, LDL<br />

particle size significantly decreased when all whole grains were incorporated into<br />

the diets. The authors concluded that the barley diets were effective in lowering<br />

heart disease risk.<br />

Another group (Lia et al. 1995) provided bread made with β-glucan-rich<br />

barley to ileostomy subjects <strong>and</strong> reported increased cholesterol <strong>and</strong> bile acid<br />

excretion in correlation with lowered blood cholesterol. Jenkins et al. (2005)<br />

compared cholesterol-lowering foods, including barley, with a statin in 34 hyperlipidemic<br />

patients <strong>and</strong> reported no significant difference in lowering LDL cholesterol<br />

between treatments. Statins act by inhibiting the action of the rate-limiting<br />

enzyme of cholesterol synthesis, HMG-CoA reductase, in the liver. For patients<br />

who cannot or desire not to take statins, this study represents dietary modification<br />

as an alternative method of controlling serum cholesterol.<br />

Spent brewers’ grain, also referred to as barley bran flour, has been tested<br />

as a hypocholesterolemic ingredient (Chaudhary <strong>and</strong> Weber 1990). Lupton et al.<br />

(1994) supplemented diets of 79 hypercholesterolemic subjects with either<br />

30 g per day of barley bran flour or 3 g per day of barley oil. Both supplements<br />

significantly decreased total <strong>and</strong> LDL cholesterol after 30 days. In that<br />

study, the barley oil treatment effect was attributed to tocotrienol content rather<br />

than β-glucan. Zhang et al. (1991) studied individuals with ileostomies who were<br />

given high-fiber diets containing spent brewers’ grain. Subjects had increased<br />

excretion of cholesterol concurrent with lowered serum LDL cholesterol.<br />

Extracted β-Glucan as a <strong>Food</strong> Additive<br />

The concept of utilizing extracted, concentrated oat or barley β-glucan as an<br />

additive to foods to produce a health benefit without the total bulk <strong>and</strong> calories<br />

of the original grain has been pursued. Brennan <strong>and</strong> Cleary (2005) published an<br />

exhaustive review on the potential of cereal β-glucans as functional food ingredients,<br />

which stressed the necessity of optimal extraction procedures to assure<br />

consistent efficacy of products in which the β-glucan is incorporated. Poppitt<br />

(2007) reiterated the need <strong>for</strong> caution in assuming that β-glucan extracts are<br />

always effective in lowering cholesterol. In human studies of barley β-glucan<br />

efficacy, whether whole grain, milling fractions, or extracted β-glucan preparations<br />

are used, there can be inconsistencies in results. The original variety of<br />

barley used, the processing <strong>and</strong> analytical techniques used, <strong>and</strong> the preparation

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