Health is of great concern to almost everyone. It may not appear to be such a concern to Americans who eat so many fat-laden fast foods. The news media is filled with articles about obesity as a result of elevated fat intake. Many of our agricultural products have great nutritional characteristics that are included in heart-healthy diets. The basic food groups contain many of the agricultural commodities we grow, such as fruits, vegetables, whole grains, meats and dairy products. Because pecans contain an average of 72 percent fat, which is similar to other nuts, many people consider them unhealthy but recent research has proven quite the contrary.
Dr. Sabate' of Loma Linda University 1 found consumption of pecans significantly lowered human blood cholesterol levels in research subjects. Healthy test subjects were placed on the American Heart Association's (AHA) Step One diet, which is low in fat, and compared to a Step One diet with the addition of pecans as a portion of the diet. Sabate's research showed that not only did the diet containing pecans lower total LDL (bad cholesterol) over the recommended Step One diet, it also helped maintain desirable levels of HDL (good cholesterol). Even though the diet containing pecans had greater fat content than the low fat Step One diet, it still lowered LDL while increasing HDL. The blood triglyceride levels from the test subjects were significantly lower than the Step One diet participants. Triglycerides are similar to cholesterol in that elevated levels of either, and especially both, are bad.
While the diet containing pecans was twice as effective in lowering cholesterol as the AHA Step One diet, Sabate' 1 also noted that the study participants commented on the enhanced taste, palatability, and satiety of food containing pecans compared to the Step One diet. He also reported that even though the addition of pecans elevated the fat content of the diet, it did not cause participants to gain weight.
A study published in June by the Harvard School of Public Health 2 in Boston, Mass., showed a lower risk of sudden cardiac death and other coronary heart disease with test subjects that frequently eat nuts. The study compared men who ate nuts at least twice per week with those who only consumed nuts rarely, if ever. The U.S. Physicians Health Study involved some 21,454 male physicians, from 40 to 84 years old, who were enrolled in the study for an average of 17 years. It indicated a 47 percent lower risk of sudden cardiac deaths and 30 percent lower risk of total coronary heart disease for those who consumed nuts, including pecans.
Preliminary research presented at the American Diabetes Association 2002 Annual Conference indicated that frequent nut consumption is associated with lower risk of Type II diabetes in women. The study is being conducted by Harvard Health Sciences using a Nurses Health Study group that involves 83,818 women aged 34 to 59 years. The 16 years of follow-up data indicates nut consumption in this study was inversely associated with risk of diabetes.
Research being conducted on artery health at the University of Bern in Switzerland 3 has indicated that alpha tocopherol (a form of vitamin E) has a significant effect on the smoothness of the artery lining. Their research indicates that it reduces the collection of blood platelets that can cause arterial blockage. Dr. Eitenmiller, of the University of Georgia 4, tested pecans for their alpha tocopherol content. All varieties tested were shown to be a good source of vitamin E, especially alpha tocopherol.
Table 1 compares the vitamin E and alpha tocopherol levels of pecan and some other healthy foods. The levels are furnished by the USDA Nutrient Data Laboratory.
The American Heart Association 5 warns against the consumption of too many calories from fat, and further defines the bad fat to be saturated. They explain the fat from nuts is polyunsaturated or monounsaturated (walnuts, almonds and pecans), which don't have cholesterol and are good sources of energy and protein. Macadamia nuts and other associated foods, such as coconuts, contain mostly saturated fats.
More studies are underway to determine the long-term effects of what we consume in our diets. The platform of President Bush's Secretary of Health and Human Services, Tommy Thompson, is "prevention" rather than treatment. With his concern about prevention of health problems, more research on these issues will be forthcoming.
With the great nutrition characteristics pecans exhibit and the positive effect they may have on human health, they should only be included in a healthy diet with many other wholesome foods. I would hope that these studies help people to understand that pecans can be included in a healthy diet.
- S. Rajaram, K. Burke, B. Connell, T. Myint and Joan Sabate'. 2001. A Monounsaturated Fatty Acid-Rich- Enriched Diet Favorably Alters the Serum Lipid Profile of Healthy Man and Women. Journal of Nutrition 131:2275-2279.
- C. M. Albert, MD, MPH; J. M. Gaziano, MD, MPH; W. C. Willett, DrPH; J. E. Manson, MD, DrPH. 2002. Nut Consumption and Decreased Risk of Sudden Cardiac Death in the Physicians' Health Study. Archives of Internal Medicine 162:1382-1387.
- A. Azzi, I. Breyer. M. Feher, M. Pastori, R. Ricciarelli, S. Spycher, M. Staffieri, A. Stocker, S. Zimmer and J. Zingg. 2000. Specific Cellular Response to Alpha-Tocopherol. Journal of Nutrition 130:1649-1652.
- J. Chun, J. Lee, L. Ye and R. R. Eitenmiller. 2002. Effects of Variety and Crop Year on Tocopherols in Pecans. Journal of Food Science 67:4: 1356-1359.
- American Heart Association. Web Site: http://18.104.22.168/presenter.jhtml?identifier=537. 8-20-2002