Click on link to read news:

News 1 / News 2

PHYTOCHEMICAL- AND FIBER-RICH SUN-DRIED RAISINS
CAN PLAY A KEY ROLE IN
CHOLESTEROL-LOWERING AND DISEASE-PREVENTION DIETS

Whole Foods Study Reinforces Fiber- and Phytochemical-Rich-Diet Link
to Cardiovascular Disease Prevention and Colon Health


A diet based on unrefined plant foods high in fiber, phytochemicals, vitamins and minerals as naturally occurring in food was compared to a typical low-fiber and low-phytochemical non-plant-based diet in healthy human subjects. Key foods in the "whole food" diet were sun-dried raisins and whole grain raisin bread, rounded out by other whole grain products, plenty of fruits and vegetables, beans and lentils, nuts and oil seeds like sesame. Green and ginger tea—both high in phenolic antioxidants—were chosen as the key beverages. Meat and animal products were kept to a minimum to make this a true "plant-based diet." The results were published in the Journal of the American College of Nutrition.

The subjects were first placed on a typical Western diet high in refined food that included white flour products and no whole grains, no dried fruits or nuts, limited fresh fruits and vegetables, more and free consumption of meat and other animal products for four weeks. Their serum cholesterol, LDL and HDL cholesterol and selected antioxidant blood enzymes were measured at the end of that period. Subjects were then switched for four weeks to the unrefined whole food diet: their total and LDL cholesterol and triglycerides were reduced, and no significant change occurred in their HDL cholesterol. And the body appeared to need less antioxidant defense as measured by the blood levels of superoxide dismutase and glutathione peroxidase. As expected on higher fiber diets, colon function become more regular and fecal elimination easier.

Foods like raisins high in fiber and quercetin, whole grains, nuts, and beverages like green tea are easy additions to any diet and can be key in improving blood cholesterol level and antioxidant defenses even in people unwilling to modify their total diet.

Authors: Gene Spiller, PhD and Bonnie Bruce, DrPH of the Sphera Foundation, and Leslie Klevay MD and Sandra Gallagher of the USDA-ARS Human Nutrition Research in Grand Forks, North Dakota collaborated on this project.

For more information write to Spiller@Sphera.org

From: A Diet High in Whole and Unrefined Foods Favorably Alters Lipids, Antioxidant Defenses, and Colon Function. J. Am. Coll. Nutr., 19 (1), 61-67, 2000.

Back to top

ABSTRACT PRESENTED AT THE AMERICAN COLLEGE OF NUTRITION
IN LAS VEGAS, OCTOBER 2000

EFFECT OF SUN-DRIED RAISINS ON BILE ACID EXCRETION, INTESTINAL TRANSIT TIME AND FECAL WEIGHT– A DOSE-RESPONSE STUDY. Spiller GA, Story JA, Butterfield G, Pollack M, and Spiller M. Health Research and Studies Center, Los Altos, CA; Purdue University, W. Lafayette; IN, Palo Alto VA Health Care System, Palo Alto, CA.

The combination in sun-dried raisins of dietary fiber and tartaric acid had been shown in a previous study to affect intestinal transit time (TT), fecal weight (FW) and fecal bile acid concentration (FBA) in a way that is hypothesized to help in colon cancer prevention (FASEB 10: A256 , 1996). To confirm the earlier results, 16 healthy adults were placed on a raisin-and-dried-fruit-free diet for two weeks (cycle 1). Four-day fecal collections were performed during the second week and TTs, FWs and FBAs measured. In three subsequent cycles, subjects consumed 84, 126 and 168 g/d of sun-dried raisins for two-weeks and the same measurements were repeated during the second week of the each cycle.

FW increased from 167 g/day without raisins (cycle 1) with a TT of 54 h to over 200 g/d (cycle 4) with a transit time of 41 hours. Intermediate increases in FW and decreases in TT were observed for cycles 2 and 3. FBA, a possible indicator of colon cancer risk, showed a significant decrease from 1.00±0.18 at baseline to 0.38±0.07 (mg/g wet feces ± SEM) (p<0.05) in cycle 2 and remained low in cycles 3 and 4. Concentrations of fecal lithocholic, chenodeoxycholic, cholic and deoxycholic acids showed major decreases in cycle 2 (84 g/day raisins), and their concentrations remained low in cycles 3 and 4. These results exceed what might have been expected from the amount of fiber in raisins, showing a role of the interaction of tartaric acid with fiber.

OCTOBER 2001 - ANNUAL MEETING OF THE AMERICAN COLLEGE OF NUTRITION, ORLANDO, FLORIDA.

SUN-DRIED RAISINS RAISE PLASMA POSTPRANDIAL ANTIOXIDANT STATUS IN HEALTHY ADULTS.

Spiller, GA AND Miller, AF. Sphera Foundation, Los Altos, CA.

Two abstracts were presented at the 42nd annual meeting of the American College of Nutrition on Saturday, October 6, 2001 from 3:15 pm to 3:40 pm, described the results of studies on the effect on blood antioxidant status of two different types of plant foods, a dried fruit, sun-dried raisins, and a seed, almonds, both high in antioxidant phytochemicals such as quercetin and kaempferol. Blood plasma ORAC (Oxygen Radical Absorbance Capacity), a key way to measure antioxidant status, was measured at fasting and 15, 30 and 60 minutes after consumption of either sun-dried raisins in one study or unblanched almonds in another study. Both foods were homogenized in water to insure proper absorption. All subjects rested during the test to avoid any effects of exercise.

Both foods caused an increase in the antioxidant power of the blood after 15 and 30 minutes and in most cases declined to either the fasting level or to a value slightly higher than the fasting level after 60 minutes in most subjects, showing that the antioxidants had moved from the blood into various tissues, the ultimate important target for protection. ORAC values increased in the blood from 8% to 16%.

It appears that the addition to the diet of dried fruits like sun-dried raisins and of nuts like almonds is a convenient and pleasant way to increase blood antioxidant status. The consumption of these foods could be valuable before oxidative stress such as strenuous physical activity. The "trail mixes" popular with hikers and other athletes, and where raisins and nuts are mixed as a great source of lasting energy, might have this additional antioxidant advantage of preventing oxidative damage.

Back to top

What is SPHERA / Books / News / Videos
Sun-dried Raisins / Raisin News / Nuts and Health