California Avocado Commission: Nutritional Benefits of Avocados
The California Avocado Commission was created to cost-effectively build value for the California avocado brand through demand-building programs including advertising, merchandising, foodservice, public relations, and nutrition. We are proud to say we have succeeded. Grower value has never been higher, and the demand for fresh California avocados continues to grow.
The science of nutrition has evolved in recent years with the discovery of how important nutrients and phytochemicals are for maintaining health. The California Avocado Commission has developed educational resources for health and food professionals to highlight these recent topics of nutrition and health.
Nutritional Benefits of Avocados
Avocados are a fresh, nutrient-dense part of a healthy diet. They have a rich, delicious flavor, and, as recent studies have shown, avocados provide vital nutrients, increase the absorption of phytochemicals in fruits and vegetables, and may help protect against a variety of chronic diseases. Providing only 48 calories per ounce, avocados promote dietary satisfaction and satiety because of their high water and fiber content, and should be a natural, wholesome component of healthy diets.
Protective Nutrients in Avocados (California Avocado Commission)
- Lutein: protects against prostate cancer and eye diseases such as cataracts and macular degeneration.
- Vitamin E: a powerful antioxidant known to slow the aging process and protect against heart disease and various forms of cancer.
- Glutathione: functions as an antioxidant like vitamin E to neutralize free radicals that can cause cell damage and lead to disease.
- Beta-sitosterol: lowers blood cholesterol levels. Avocados contain four times as much beta-sitosterol as oranges, previously reported as the highest fruit source of this phytochemical.
- Monounsaturated fats: heart-healthy fats proven to help lower LDL (bad) cholesterol and boost HDL (good) cholesterol.
- Folate: promotes healthy cell and tissue development. Folate is especially important for woman of childbearing age as it helps protect against birth defects.
- Potassium: helps balance the body's electrolytes. Avocados contain 60 percent more potassium than bananas.
- Magnesium: helps produce energy and is important for muscle contraction and relaxation.
- Fiber: lowers cholesterol and reduces risk of heart attack.
Nutritional Components of Avocados That Contribute to Disease Risk Reduction
Avocados are rich sources of nutrients (1) that decrease cardiovascular risk including monounsaturated fats, that lower LDL and raise HDL, and beta-sistosterol, that decreases absorption of dietary cholesterol and promotes lower blood cholesterol levels. Recent research suggests that monounsaturated fats are burned more efficiently after exercise than saturated fats, and may contribute to long-term weight loss (11 – 12).
Vitamin E in avocados decreases risk of heart disease and various forms of cancer as well as providing valuable antioxidants to slow the aging process. Other vitamins and minerals present in avocados include folate, that promotes cell and tissue development and reduces birth defect risk; potassium, for electrolyte balance; and magnesium, which is important for energy metabolism as well as muscle contraction and relaxation.
Avocados also contain generous amounts of glutathione, which acts as an antioxidant to neutralize free radicals that promote cell damage, as well as leutein, a carotenoid, that has been shown to protect against prostate cancer, cataracts, and macular degeneration. Research conducted by Dr. David Heber from UCLA has determined that lutein, a disease-reducing nutrient in avocados, reduced prostate cancer cell growth when paired with other phytonutrients like lycopene. This research will be published in an upcoming issue of the Journal of Nutritional Biochemistry, and further supports the cancer risk reduction properties of lutein and lycopene in avocados. In addition, avocados are an excellent source of fiber, which lowers cholesterol levels and reduces heart attack risk (3, 5 – 7, 9).
Improvement in Absorption of Other Nutrients by Avocados
Recent research conducted at Ohio State University (10) concluded that the lipids present in avocados significantly increase absorption of carotenoids. Findings from this study were presented at the July 2004 meeting of the Institute of Food Technologists, and have been published in The Journal of Nutrition in early 2005 (2). Many fruits and vegetables contain beneficial carotenoids but are virtually fat free, which limits absorption of these valuable nutrients. Previous studies have indicated that the bioavailability of many nutrients, including carotenoids, is enhanced by foods that contain fat (1). The lipids present in avocados can significantly increase absorption of beneficial carotenoids in salads and salsa (lycopene, alpha- and beta-carotene), which offers nutritional advantages over saturated fats, gums, and preservatives often present in processed salad dressings. The enhanced bioavailability of carotenoids is due primarily to the lipids present in avocado (2).
The adult men and women subjects in the Ohio State University study (10) consumed salads and salsa with and without avocado. Subjects who consumed salsa with 150 g avocado absorbed 4.4 times more lycopene, which has been shown to reduce incidence of prostate cancer, and two times more beta-carotene, which promotes heart-health and reduces cancer risk, than subjects who consumed salsa without avocados. Subjects who consumed a lettuce, carrot, and spinach salad containing 75 g avocado (2.5 tablespoons) absorbed 8.3 times more alpha-carotene and 13.6 times more beta-carotene, both of which have been shown to protect against heart disease and cancer. These subjects also absorbed 4.3 times more leutein, which promotes eye health and protects against macular degeneration, the leading cause of blindness in the elderly. The authors conclude that avocados act as a "nutrient booster" by enhancing absorption of heart-healthy, cancer-fighting lycopenes, alpha-carotenes, and beta-carotenes found in fruits and vegetables (2).
Beneficial Nutrients in Avocados Recommended by Health Agencies
Avocados provide heart-healthy lipids in addition to beneficial antioxidants and phytochemicals. Compared to other commonly eaten fruits, avocados rank highest in monounsaturated fat, vitamin E, folate, potassium, magnesium, lutein, beta-sistosterol and glutathione. The Food and Drug Administration promotes diets rich in fruits and vegeables to reduce risk of cancer and other chronic diseases.
The American Diabetes Association recommends diets containing the monounsaturated fats found in avocados to improve glucose tolerance and reduce insulin resistance (4). A recent issue of Diabetes Care reported that a study that included over 85,000 women and nearly 43,000 men who consumed magnesium-rich foods, like avocados, were less likely to develop Type II diabetes (8). Consumption of avocados is promoted in dietary recommendations from many of the world's leading nutrition organizations: USDA's Dietary Guidelines for Americans, Produce for Better Health's 5 A Day Program, American Diabetes Association's Diabetes Food Pyramid, UCLA Center for Human Nutrition's California Cuisine Food Pyramid, and Oldways Preservation & Exchange Trust's Mediterranean, Vegetarian, and Latin American Diet Pyramids (6).
Summary Recommendations
Nutritionists and dietitians continue to encourage people to consume diets composed of nutrient-dense foods. Compared to other commonly eaten fruits, avocados rank among the highest in monounsaturated fat, vitamin E, folate, potassium, magnesium, lutein, beta-sistosterol, and glutathione, yet contain only 48 calories per ounce. In addition, avocados allow the body to absorb significantly more alpha-carotene, beta-carotene, and lycopene found in fruits and vegetables. Avocados, therefore, provide disease-fighting nutrients that work with other dietary components to promote health and reduce the risk of chronic diseases such as heart disease and cancer. In summary, avocados are a natural and wholesome part of a healthy diet.
References
- California Avocado Healthy Times, A California Avocado Commission Publication, 2005.
- California Avocado Information Bureau Release, New Research Shows Avocados Act as Nutrient Booster, August 2, 2004.
- Code of Federal Regulations, Title 21: Food and Drugs. Appendix C to Part 101-Nutrition Facts for Raw Fruits and Vegetables, 2002.
- Diabetes: A Growing Epidemic, California Avocado Healthy Times, A California Avocado Commission Publication, 2005.
- Duester, K.C. Avocado fruit is a rich source of beta-sistosterol. J Am Diet Assoc 101: 404-405, 2001.
- Get the Scoop on What's Good, California Avocado Commission, 2004.
- Jones, D.P., Coates, R.J., Flagg, E.W., Elley, J.W., Block, G., Greenberg, R.S., Guenter, E.W., and Jackson, B. Glutathione in foods listed in the National Cancer Institute's Health Habits and History Food Frequency Questionnaire. Nutr Cancer 17: 57-75, 1992.
- Lopez-Ridaura, R., Willet, W.C., Rimm, E.B., Liu, S., Stampher, M.J., Manson, J.E., and Hu, F.B. Magnesium intake and risk of Type 2 diabetes in men and women. Diabetes Care 27: 134-140, 2004.
- U.S. Department of Agriculture, Agricultural Research Service, 2003. USDA Nutrient Database for Standard Reference, Release 16. Nutrient Data Laboratory Home Page, http://www.nal.usda.gov/fnic/foodcomp
- Unlu, Z.N., Bohn, T., Clinton , S., Schwartz, S.J. Enhanced carotenoid bioavailability in humans from salad and salsa with addition of avocado or avocado oil. The Ohio State University, September 20, 2004.
- Votruba, S.B., Atkinson, R.I., Hirvonen, M.D., and Schoeller, D.A. Prior exercise increases subsequent utilization of dietary fat. Med Sci Sport Exer 34: 1757-1763, 2002.
- Votruba, S.B., Atkinson, R.I., Schoeller, D.A. Prior exercise increases dietary oleate, but the palmitate oxidation. Obes Res 11(12): 1509-1518, 2003.