Oat Bran Shown to Improve Numerous Blood Factors that Improve Health

by | Aug 10, 2011 | 2011, Blood Lipids, Cardiovascular Health, Fiber, Whole Foods - General

Written by Greg Arnold, DC, CSCS. In a study with 24 young adults, those consuming oat bran had 10% greater improvement in total cholesterol and other benefits.

The health benefits of oat bran became official in 1996 when the FDA approved the first food-specific health claim for foods containing whole oat sources of soluble fiber (oats, oat bran, and oat flour) to reduce the risk of coronary heart disease (1, 2) which affects more than 16 million Americans, caused 451,326 deaths in 2004 and is the single leading cause of death in America today (3).

Oat bran’s heart health benefits lie in helping maintain healthy cholesterol levels (4) due in part to a component of oats called beta glucan (5) which can help maintain healthy liver function (6,7) and healthy insulin levels (8).  Finally, antioxidants in oats called avenanthramides helps keep blood vessels healthy (9).

Now a new study (10) has found more evidence of oat bran’s heart-health benefits. In the study, 24 adults between the ages of 22 and 28 with a body massindex between 22 and 28 kg/m2 followed either a low-fiber diet (control group – 35% fat, 15% protein, 50% carbohydrate (16 grams fiber per day)) or an oat bran diet (102 grams of oat bran providing 26 grams fiber per day) for 2 weeks. The patients provided blood samples before and after the study to measure cholesterol levels but also provided stool samples from the last 3 days of the study to allow researchers to further assess digestive health by measuring stool volume.

After two weeks, the results were:

  • Total Cholesterol in Oat Bran Group – Decreased by 14% (4.08 to 3.49 mmol/L)
  • Total Cholesterol in Control Group – Decreased by 4% (3.97 to 3.81 mmol/L) (p < 0.001
  • HDL Cholesterol in Oat Bran Group – Decreased by 16% (2.77 to 2.33 mmol/L)
  • HDL Cholesterol in Control Group – Decreased by 3% (2.71 to 2.63 mmol/L) (p < 0.01).
  • Total Triacylglycerol in Oat Bran Group – Decreased by 21% (0.89 to 0.70 mmol/L) decrease
  • Total Triacylglycerol in Control Group – Decreased by 10% (0.84 to 0.76 mmol/L)  (p < 0.05).
  • Very-Low-Density Lipoprotein Triacylglycerol in Oat Bran Group – Decreased by 33% (0.61 to 0.41 mmol/L)
  • Very-Low-Density Lipoprotein Triacylglycerol in Control Group – Decreased by 9% (0.56 to 0.46 mmol/L)  (p < 0.01).

Regarding the stool samples, fecal volume was 45% larger during the oat bran period compared with the control period (197 vs. 136 g per day, p < 0.001), which produced a 37% increase in energy excretion (1014 v.s 638 kilojoules/day, p < 0.001).

The researchers saw the health value in this because the average American adult gains up to 2.2 pounds per year due to an extra 200 kilojoules per day imbalance (11). Therefore, the extra oat bran intake may be able to offset this imbalance and implement a ‘small changes strategy’ to prevent weight gain. The researchers do admit, however, that “this needs to be addressed in a longer-term study, preferably in overweight participants.”

For the researchers, “the results of the present study suggest that a diet high in oat bran significantly improves multiple cardiovascular risk factors in healthy young adults.”

Source: Kristensen, Mette, and S. Bügel. “A diet rich in oat bran improves blood lipids and hemostatic factors, and reduces apparent energy digestibility in young healthy volunteers.” European journal of clinical nutrition 65.9 (2011): 1053-1058.

© 2011 Macmillan Publishers Limited All rights reserved

Posted August 10, 2011.

References:

  1. US Department of Health and Human Services, Food and Drug Administration. Health claims: oats and coronary heart disease—proposed rule. Fed Regist. 1996;61:296-337.
  2. US Department of Health and Human Services, Food and Drug Administration. Health claims: oats and coronary heart disease—final.
  3.  “Cardiovascular Disease Statistics” posted on the American Heart Association website.
  4.  AndonMB. State of the Art Reviews: The Oatmeal-Cholesterol Connection: 10 Years Later. American Journal of Lifestyle Medicine 2008 2: 51-57.
  5. Mensink RP. ß-Glucan incorporated into a fruit drink effectively lowers serum LDL-cholesterol concentrations. Am. J. Clinical Nutrition, Mar 2006; 83: 601 – 605.
  6. Andersson M, Ellegard L, Andersson H. Oat bran stimulates bile acid synthesis within an 8 h as measured by 7-alphahydroxy- 4-cholesten-3-one. Am J Clin Nutr. 2002;76:1111-1116.
  7. Ellegard L, Andersson H. Oat bran rapidly increases bile acid excretion and bile acid synthesis: an ileostomy study. Eur J Clin Nutr. 2007;61:938-945.
  8. Maki KC. Effects of consuming foods containing oat beta-glucan on blood pressure, carbohydrate metabolism and biomarkers of oxidative stress in men and women with elevated blood pressure. Eur J Clin Nutr advance online publication, December 6, 2006; doi:10.1038/sj.ejcn.1602562.
  9. Meydani M. Mechanism by which avenanthramide-c, a polyphenol of oats, blocks cell cycle progression in vascular smooth muscle cells. Free Radic Biol Med 2006;41(5):702-8.
  10. Kristensen M. A diet rich in oat bran improves blood lipids and hemostatic factors, and reduces apparent energy digestibility in young healthy volunteers. European Journal of Clinical Nutrition 2011; 1-6.
  11.  Hill JO (2006). Understanding and addressing the epidemic of obesity: an energy balance perspective. Endocr Rev 27, 750–761.