Folate: A Key to Optimizing Health and Reducing Disease Risk in the Elderly

Abstract

Inadequate folate status is associated with an increased risk for chronic diseases that may have a negative impact on the health of the aging population. Folate, a water-soluble vitamin, includes naturally occurring food folate and synthetic folic acid in supplements and fortified foods. Inadequate folate status may result in hyperhomocysteinemia, a significant risk factor for atherosclerotic vascular disease, changes in DNA that may result in pro-carcinogenic effects and increased risk for cognitive dysfunction. Folate status may be negatively influenced by inadequate intake, genetic polymorphisms and interactions with various drugs. In the US, folic acid is now added to enriched grain products and continues to be included in the majority of ready-to-eat breakfast cereals. Recent data indicate that the folate status in the US population has improved significantly, presumably due to the effects of fortification. Folic acid (not food folate) intake in excess of the Tolerable Upper Intake Level may mask the diagnosis of a vitamin B₁₂ deficiency, which is more prevalent in the elderly than younger individuals. When folic acid supplements are recommended, a multivitamin that includes vitamin B₁₂ should also be advised. To safely and effectively increase folate intake in the elderly, naturally occurring folate-rich food sources should be promoted. Folate-rich foods include orange juice, dark green leafy vegetables, asparagus, strawberries and legumes. These foods are also excellent sources of other health-promoting nutrients associated with chronic disease risk reduction.

• folic acid
• folate
• homocysteine
• vitamin B 12
• aged
• chronic disease

Key teaching points:

• Adequate folate intake and status has been associated with reduced risk for chronic conditions that may particularly affect the elderly, including hyperhomocysteinemia, a risk factor for vascular disease, cancer and cognitive dysfunction.

• Folate status can be impacted negatively by low intake, genetic polymorphisms or use of antifolate medications such as methotrexate, which is commonly used to treat rheumatoid arthritis.

• Folic acid intakes in excess of the Tolerable Upper Intake Level (UL) (1 mg/day) may mask the symptoms associated with a vitamin B₁₂ deficiency and allow for the progression of irreversible neurological damage. The UL is applicable to intakes of synthetic folic acid, but not folate occurring naturally in foods.

• The elderly are at increased risk for vitamin B₁₂ deficiency due to food-bound malabsorption associated with hypochlorhydria or achlorhydria, conditions which are prevalent among the elderly.

• Patients taking antifolate medications or presenting with megaloblastic anemia or hyperhomocysteinemia should be screened for both folate and vitamin B₁₂ deficiency. Chronic therapy with folic acid for the elderly should be coupled with vitamin B₁₂ supplements.

• Practitioners should encourage intake of folate-rich foods such as orange juice, dark green leafy vegetables, asparagus, strawberries and legumes, which can provide a variety of other nutrients beneficial to the health status of the elderly without the danger of exceeding the UL.

Key teaching points:

• Adequate folate intake and status has been associated with reduced risk for chronic conditions that may particularly affect the elderly, including hyperhomocysteinemia, a risk factor for vascular disease, cancer and cognitive dysfunction.

• Folate status can be impacted negatively by low intake, genetic polymorphisms or use of antifolate medications such as methotrexate, which is commonly used to treat rheumatoid arthritis.

• Folic acid intakes in excess of the Tolerable Upper Intake Level (UL) (1 mg/day) may mask the symptoms associated with a vitamin B₁₂ deficiency and allow for the progression of irreversible neurological damage. The UL is applicable to intakes of synthetic folic acid, but not folate occurring naturally in foods.

• The elderly are at increased risk for vitamin B₁₂ deficiency due to food-bound malabsorption associated with hypochlorhydria or achlorhydria, conditions which are prevalent among the elderly.

• Patients taking antifolate medications or presenting with megaloblastic anemia or hyperhomocysteinemia should be screened for both folate and vitamin B₁₂ deficiency. Chronic therapy with folic acid for the elderly should be coupled with vitamin B₁₂ supplements.

• Practitioners should encourage intake of folate-rich foods such as orange juice, dark green leafy vegetables, asparagus, strawberries and legumes, which can provide a variety of other nutrients beneficial to the health status of the elderly without the danger of exceeding the UL.

This article is presented as Florida Agricultural Experiment Station Journal Series No. R-09049.

Notes

Gail C. Rampersaud’s position at the University of Florida is co-sponsored by the Florida Department of Citrus.

Presented in part at the 42^nd Annual Meeting of the American College of Nutrition, Orlando, Florida, October 4, 2001.