Inadequate Diet Can Lead to Anemia in Postmenopausal Women
Postmenopausal women are at a greater risk of developing anemia if their diet is one of inadequate nutrition even if multivitamin supplements are used according to a new study published in the April 2011 issue of the Journal of the American Dietetic Association.
Cynthia A. Thomson, PhD, RD, Associate Professor Nutritional Sciences, University of Arizona, Tucson, and colleagues used data from 72,833 women in the Observational Cohort of the Women's Health Initiative (WHI-OS), one of the most comprehensive sources of diet, health and general information ever collected in the U.S.. Over a 9-year period, dietary intake data were collected using a Food Frequency Questionnaire (FFQ). The FFQ estimates intake of over 85 nutrients.
Thomson and colleagues found that deficiencies in more than a single nutrient were associated with a 21% greater risk of persistent anemia while three deficiencies resulted in a 44% increase in risk for persistent anemia.
Women with anemia reported lower intakes of protein, folate, vitamin B12, iron, vitamin C and red meat. In fact, inadequate intake of dietary iron, vitamin B12 and folate were each associated with approximately 10% to 20% elevated risk for incident anemia among WHI-OS study participants and the odds increased for persistent anemia to 21%.
"This study suggests that inadequate nutrient intakes are a significant risk factor for anemia in this population of older women and use of multivitamin/mineral supplements is not associated with lower rates of anemia," reported Thomson.
Inadequate intakes of multiple anemia-associated nutrients were less frequent in non-Hispanic whites (7.4%) than other race/ethnic groups (15.2% of Native Americans/Alaskans, 14.6% Asian/Pacific Islanders, 15.3% of African Americans and 16.3% of Hispanic/Latinos reported all three nutrient inadequacies).
Age, body mass index and smoking were also associated with anemia.
Thomson notes, "Overall mortality is increased in relation to a diagnosis of anemia, and anemia, particularly iron deficiency, has been associated with reduced capacity for physical work and physical inactivity, injury related to falls and hospitalizations, making this an important health care concern in the aging."
The authors point out that there have been few studies of anemia and diet of independently living women in the past 20 years.
The authors conclude that, "Efforts to identify anemia that may be responsive to modifiable factors such as diet to improve health outcomes are needed. Additional efforts to regularly evaluate postmenopausal women for anemia should be considered and should be accompanied by an assessment of dietary intake to determine adequacy of intake of anemia-associated nutrients including iron, vitamin B12 and folate. While the type of anemia is often designated by a more comprehensive biochemical assessment than hemoglobin alone, nutritional therapy to improve overall nutrient-density and quality of the diet should also be a clinical focus."
In an accompanying podcast Dr. Cynthia A. Thomson discusses the importance and implications of nutrient Intake and anemia risk in the WHI Observational Study. It is available at http://adajournal.org/content/podcast.
Iron deficiency anemia (IDA) is the most common type of anemia. IDA occurs when the there is inadequate iron in the diet. Meat, poultry, fish, eggs, dairy products, or iron-fortified foods are the best sources of iron found in food.
Vitamin deficiency anemia (or megaloblastic [MEG-uh-loh-BLASS-tik] anemia) is most often caused by low levels of vitamin B12 or folate.
Vitamin B12 deficiency anemia (or pernicious [pur-NISH-us] anemia) occurs due to a lack of vitamin B12 in the diet or to a lack of the body’s ability to absorb the vitamin due to an autoimmune disorder or intestinal problems.
Vitamin B12 is found in foods that come from animals. Fortified breakfast cereals also have vitamin B12. With this type of anemia, your doctor may not realize that you're not getting enough vitamin B12.
Folate deficiency anemia occurs when the body doesn’t have enough folate or folic acid. It occurs from similar mechanisms as vitamin B12 deficiency does: not enough in the diet or poor absorption.
Folate is a B vitamin found in foods such as leafy green vegetables, fruits, and dried beans and peas. Folic acid is found in fortified breads, pastas, and cereals.
Journal of the American Dietetic Association, news release, March 25, 2011
Nutrient Intake and Anemia Risk in the WHI Observational Study; Cynthia A. Thomson, PhD, RD, Jeffrey Stanaway, MPH, Marian L. Neuhouser, PhD, RD, Linda G. Snetselaar, RD, PhD, LD, Marcia L. Stefanick, PhD, Leslie Arendell, MS, and Zhao Chen, PhD, MPH; Journal of the American Dietetic Association, April 2011, Vol 111, Issue 4, Pages 532-541