Effects of Prolonged Whey Protein Supplementation and Resistance Training on Biomarkers of Vitamin B12 Status: A 1-Year Randomized Intervention in Healthy Older Adults (the CALM Study).

Eva Greibe,Lars Holm,Jacob Bülow,Rasmus L Bechshøft,Inge Tetens,Søren Reitelseder,Christian W Heegaard,Ulla R Mikkelsen,Simon R Schacht,Ebba Nexo,Marie S Ostenfeld,Mads L Knudsen,Grith W Højfeldt

doi:10.3390/nu12072015

Abstract

We investigated the effect of long-term whey supplementation on biomarkers of B12 status in healthy older adults subjected to different schemes of supplements and exercise. The total study population examined at baseline consisted of 167 healthy older adults (age ≥ 65 year) who were randomized to 1-y intervention with two daily supplements of (1) whey protein (3.1 µg B12/day) (WHEY-ALL), (2) collagen (1.3 µg B12/day) (COLL), or (3) maltodextrin (0.3 µg B12/day) (CARB). WHEY-ALL was comprised of three groups, who performed heavy resistance training (HRTW), light resistance training (LITW), or no training (WHEY). Dietary intake was assessed through 3-d dietary records. For the longitudinal part of the study, we included only the participants (n = 110), who met the criteria of ≥ 50% compliance to the nutritional intervention and ≥ 66% and ≥ 75% compliance to the heavy and light training, respectively. Fasting blood samples collected at baseline and 12 months and non-fasting samples collected at 6 and 18 months were examined for methylmalonic acid, B12 and holotranscobalamin. At baseline, the study population (n = 167) had an overall adequate dietary B12 intake of median (range) 5.3 (0.7–65) µg/day and median B12 biomarker values within reference intervals. The whey intervention (WHEY-ALL) caused an increase in B12 (P < 0.0001) and holotranscobalamin (P < 0.0001). In addition, methylmalonic acid decreased in the LITW group (P = 0.04). No change in B12 biomarkers was observed during the intervention with collagen or carbohydrate, and the training schedules induced no changes. In conclusion, longer-term daily whey intake increased plasma B12 and holotranscobalamin in older individuals. No effect of intervention with collagen or carbohydrate or different training regimes was observed. Interestingly, the biomarkers of B12 status appeared to be affected by fasting vs. non-fasting conditions during sample collection.

Highlights

Low vitamin B12/cobalamin (B12) status is estimated to affect up to 15% of people over the age of 60 years [1,2]
Median values of methylmalonic acid (MMA), B12, and holoTC are within reference intervals of adults [16,20,21]
MMA (Figure vs.mo) months afterforthe supplementation been discontinued, We found an increase in B12 and holoTC in response to 1-y whey intervention (WHEY) but no

Summary

Introduction

Low vitamin B12/cobalamin (B12) status is estimated to affect up to 15% of people over the age of 60 years [1,2]. An impaired B12 status may be caused by a lost ability to produce the gastric intrinsic factor needed for the intestinal uptake of B12. An impaired status can be caused by low. B12 intake and/or a reduced ability to release the vitamin from its carrier proteins in the food during digestion [1,5]. B12 bound to its transport protein transcobalamin (holotranscobalamin, holoTC). The latter signifies the fraction of total plasma B12 available for tissue uptake [2,5]. Methylmalonic acid (MMA) is an important diagnostic tool as this metabolite accumulates in the blood during cellular B12 insufficiency [2,5]

Methods

Results

Conclusion