Vegetarian Nutrition for the Older Adult: Vitamin B 12 , Iron, and Zinc

Purpose of Review Health organizations throughout the world advocate diets that emphasize vegetables, fruits, pulses, grains, and minimally processed staple foods as beneficial throughout life and in old age. However, concern exists that the dietary exclusion or minimalization of flesh foods may compromise the nutritional status of some nutrients, including vitamin B 12 , iron, and zinc. The purpose of this study is to discuss the metabolism and dietary sources of vitamin B 12 , iron, and zinc and review observational studies that investigate the status of these micronutrients in older vegetarians compared to their non-vegetarian counterparts. Recent Findings The few comparative studies that are available suggest that vitamin B 12 status is lower in older vegetarian compared to omnivorous populations; however, subclinical vitamin B 12 deficiency due to malabsorption is prevalent regardless of dietary pattern. Zinc status appears comparable but not optimal in either group. Whether iron status is compromised in older vegetarians compared to non-vegetarians is unclear. Summary Dietary practices that improve zinc and iron bioavailability are appropriate strategies in the management of suboptimal nutrient status in apparently healthy older vegetarian populations. Older populations may benefit from vitamin B 12 and zinc supplementation, irrespective of dietary pattern.