Contribution of Vitamin D2 and D3 and Their Respective 25-Hydroxy Metabolites to the Total Vitamin D Content of Beef and Lamb

Kevin D Cashman; Siobhan M O'Sullivan; Karen Galvin; Michelle Ryan

doi:10.1093/cdn/nzaa112

Contribution of Vitamin D₂ and D₃ and Their Respective 25-Hydroxy Metabolites to the Total Vitamin D Content of Beef and Lamb

Curr Dev Nutr. 2020 Jun 30;4(7):nzaa112. doi: 10.1093/cdn/nzaa112. eCollection 2020 Jul.

Authors

Kevin D Cashman¹, Siobhan M O'Sullivan¹, Karen Galvin¹, Michelle Ryan¹

Affiliation

¹ Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland.

Abstract

Background: Red meat and meat products can contribute meaningfully to the mean daily intake of vitamin D. Beef and lamb can contain vitamin D₃ and 25-hydroxyvitamin D₃ [25(OH)D₃] but also potentially vitamin D₂ and 25-hydroxyvitamin D₂ [25(OH)D₂], all of which contribute to meat's vitamin D activity.

Objectives: We aimed to measure the vitamin D₃, vitamin D₂, 25(OH)D₃, and 25(OH)D₂ content of Irish beef and lamb.

Methods: Full striploin steaks (longissimus dorsi) (n = 39) from beef cattle slaughtered in winter, spring, summer, and autumn as well as lamb steaks (hind leg) from sheep slaughtered in autumn (n = 8) were sourced and homogenized. The contents of all 4 vitamin D-related compounds were analyzed using an LC-tandem MS method in conjunction with the National Institute of Standards and Technology's standard reference material no. 1546a-Meat Homogenate. The total vitamin D activity of meat was defined as: {vitamin D₃ + [25(OH)D₃× 5] + vitamin D₂ + [25(OH)D₂× 5]}.

Results: The median (IQR) total vitamin D activity of striploin beef steak (n = 39, irrespective of season) was 0.56 (0.37-0.91) μg/100 g. The content of all 4 vitamin D compounds in beef steak varied significantly (P < 0.0001) with season (n = 8-11/season group). Median total vitamin D activity of beef steak increased in a stepwise manner (P < 0.0001) from winter to the following autumn (increasing from 0.31 to 1.07 μg/100 g). The mean total vitamin D activity of lamb samples (n = 8) from autumn was 0.47 μg/100 g.

Conclusions: About one-third of the total vitamin D activity of Irish beef was attributable to its combined vitamin D₂ and 25(OH)D₂ content, estimates of which are largely or completely missed in food composition tables. There was significant seasonal variation in all 4 vitamin D compounds as well as in total vitamin D activity, which has implications for vitamin D nutrient claims for beef.

Keywords: 25-hydroxyvitamin D2; 25-hydroxyvitamin D3; beef; lamb; red meat; vitamin D; vitamin D2; vitamin D3.