American Journal of Clinical Nutrition Reports Almonds' Impact on Triglycerides
MODESTO, Calif., Dec. 16 /PRNewswire-USNewswire/ -- The Almond Board of California maintains that simple changes in one's diet can help overcome dietary challenges, especially during the holiday season. Resolutions for healthier eating habits during this festive time should be maintained throughout the year, as heart disease takes 17.5 million lives worldwide annually, according to the World Health Organization report (2004). One way to improve heart health is to make dietary choices that reduce triglyceride levels, an established risk factor for developing heart disease.
With an invested interest in heart health over the course of nearly two decades, the Almond Board funded its most recent study to investigate heart health risk factors, namely high triglyceride levels. During the study, human subjects consumed muffin products made with pieces of whole almonds, compared to those made with oil. Researchers witnessed a delayed release of fats from the almonds into the body, which resulted in a lower rise in triglyceride levels.
"This new study published in the American Journal of Clinical Nutrition, expands upon previous cardiovascular research by investigating not only how the plant cell wall may impact how fats are absorbed into the body, but also the potential impact on acute changes in triglyceride levels," noted Dr. Sarah Berry, Nutritional Sciences Division, Kings College London, United Kingdom. "The data suggest that an intact plant cell wall, as found in whole almonds, may impact on how much and how quickly fat is released into the blood, contributing to a lower acute rise in blood triglyceride levels."
Researchers at King's College in London discovered that the increase in plasma triglycerides levels was lower after eating a meal that included muffins made with pieces of whole almonds than muffins made with oil-based fat sources, like almond oil and sunflower oil.
The Facts on Fats:
Triglycerides are the primary form of fat in foods, regardless of the type of fat i.e., unsaturated or saturated. Blood triglycerides normally increase after eating a meal containing dietary fat. Elevated blood triglyceride levels are a risk factor for developing cardiovascular disease.
In both in vitro and human studies, researchers explored how the fiber plant cell wall of almonds impacts the accessibility of nutrients, and in both types of studies, researchers found that the plant cell wall of almonds appears to hinder the ability to absorb all of the fat. For example, in one study using a model gut, research also found indications that the cell walls of almonds swell during digestion, becoming permeable, allowing the fat in almonds to be slowly released throughout the digestive tract.(1)
The Study at a Glance:
The People: Twenty healthy male subjects were recruited from King's College London, University of London to participate in the study.(2) The average age of the subjects was about 25 years old.
The Diet: Subjects received three experimental meals. Experimental meals consisted of custard and muffins; muffins were made with whole almond seeds, almond oil plus defatted almond flour or sunflower oil, made to provide 50g of fat. Fasting and postprandial (after meal blood) samples were obtained from subjects to measure changes in plasma triglycerides.
The Results: Researchers found that the postprandial increase in triglycerides was significantly lower (p=0.002) after the whole almond meal than after the almond oil or sunflower oil muffin meals. It appears that the fat found in whole almonds is not as quickly absorbed by the body as that found in almond oil or sunflower oil, which researchers attributed to the plant cell walls found in the whole almond nut. Researchers believe that the plant cell walls found in almonds, act as a physical barrier hindering the rate and release of the lipid during digestion.
This study published in the American Journal of Clinical Nutrition complements the nine clinical studies on almonds already in existence, demonstrating how almonds, as part of a diet low in saturated fat, can help maintain healthy cholesterol levels. Do your research for the New Year, and find out how almonds can be a part of your eating plan for heart health. Visit www.AlmondsAreIn.com/9studies.
One ounce of almonds, about a handful, offers: Fiber (3g); Calcium (75mg); Protein (6g); Iron (1.0mg); Potassium (200 mg); Saturated Fat (1g); Unsaturated Fat (13g).
Summary of Published Study:
Journal: American Journal of Clinical Nutrition, October 2008
Research Organization: Kings College London
Study Title: "Manipulation of lipid bioaccessibility of almond seeds influences postprandial lipemia in healthy human subjects."
Authors: Sarah EE Berry, Elizabeth A Tydeman, Hannah B Lewis, Ravneet Phalora, Jennifer Rosborough, David R Picout, and Peter R Ellis
Objective: Investigated the effects of lipid release (bioaccessibility) on postprandial lipemia by comparing lipid encapsulated by cell walls with lipid present as free oil.
Subjects: Twenty healthy men. The mean age of the subjects was 25.8 +/- 4.3 years
Study description: A randomized crossover trial (n 20 men) compared the effects of 3 meals containing 54 g fat provided as whole almond seed macroparticles (WA), almond oil and defatted almond flour (AO), or a sunflower oil blend as control (CO) on postprandial changes in oxidative stress (8-isoprostane F2 concentrations), vascular tone (peripheral augmentation index), and plasma triacylglycerol, glucose, and insulin concentrations.
Results: The postprandial increase in plasma triacylglycerol was lower [74% and 58% lower incremental area under curve (iAUC)] after the WA meal than after the AO and CO meals (P 0.001). Increases in plasma glucose concentrations (0-180 min) were significantly higher after the WA meal (iAUC: 114; 95% CI: 76, 153) than after the AO meal (iAUC: 74; 95% CI: 48, 99) (P 0.05), but no significant differences from the CO meal were observed (iAUC: 88; 95% CI: 66, 109). The peak reductions in peripheral augmentation index after the WA, AO, and CO meals (9.5%, 10.1%, and 12.6%, respectively, at 2 h) were not significantly different between meals. Plasma 8-isoprostane F2 and insulin concentrations did not differ significantly between meals.
(1) Mandalari, G. Faulk, RM, Rich GT, Lo Turco V, Picout DR, Lo Curto RB, Bisignano G, Dugo P, Dugo G, Waldron KW, Ellis PR, Wickham M.S.J. Release of protein, lipid, and vitamin E from almond seeds during digestion. J Agric Food Chem 2008 May 14;56(9):3409-16. Epub 2008 Apr 17. http://pubs.acs.org/doi/pdfplus/10.1021/jf073393v
(2) Sarah EE Berry, Elizabeth A Tydeman, Hannah B Lewis, Ravneet Phalora, Jennifer Rosborough, David R Picout, and Peter R Ellis. Manipulation of lipid bioaccessibility of almond seeds influences postprandial lipemia in healthy human subjects. Am. J. Clinical Nutrition, Oct 2008; 88: 922 - 929.
The Almond Board of California administers a grower-enacted Federal Marketing Order under the supervision of the United States Department of Agriculture. Established in 1950, the Board's charge is to promote the best quality almonds, California's largest tree nut crop. For more information on the Almond Board of California or almonds, visit www.AlmondsAreIn.com.
SOURCE Almond Board of California