Researchers from the Netherlands investigated the effects of dairy-derived protein and vitamin D on the physical fitness and overall nutritional profile of older people. The study, published in the journal Nutritional Research, aims to broaden the body of evidence highlighting the effectiveness of the supplementation in improving physical performance and nutrient status.
This study is a systematic review and meta-analysis of related trials in the Scopus and MEDLINE databases. The researchers pulled 36 trials with a total of 4,947 participants.
The researchers set the following criteria for the chosen articles: double-blind, randomized, placebo-controlled trials; in particular, the studies included participants aged 55 years or older who received supplementation or a placebo.
Nutrient status (body weight and body mass index) and physical fitness (body composition, muscle strength, and physical performance) were used as outcome measures.
Most trials indicated that protein and vitamin D supplementation showed no effect on the outcomes.
The meta-analysis revealed that protein significantly increased body weight by a mean difference of 1.13 kg (95 percent confidence interval, 0.59-1.67). This effect increased by selecting trials that lasted for six months and involved less nourished and physically fit participants.
Protein supplementation increased lean body mass as shown in trials involving (pre-)frail, inactive older participants, or when supplementing 20 g or more of protein per day.
Only small significant effects of vitamin D supplementation were observed in participants that took Timed Up and Go tests (mean difference -0.75 seconds; 95 percent confidence interval -1.44 to -0.07).
This effect increased when vitamin D doses ranged between 400 and 1,000 IU.
The researchers posit that supplementing with adequate amounts of dairy-derived protein (20 g or more) and vitamin D (400-1,000 IU) may exhibit desired effects on the nutrient profile and physical performance of malnourished or frail older people.
To learn more about the effects of protein and vitamin D on aging bodies, visit AgingSecrets.news.
Journal Reference:
Dewansingh P, Melse-Boonstra A, Krijnen WP, Schans CPVD, Jager-Wittenaar H, Heuvel EGVD. SUPPLEMENTAL PROTEIN FROM DAIRY PRODUCTS INCREASES BODY WEIGHT AND VITAMIN D IMPROVES PHYSICAL PERFORMANCE IN OLDER ADULTS: A SYSTEMATIC REVIEW AND META-ANALYSIS. Nutrition Research. 2018;49:1–22. DOI: 10.1016/j.nutres.2017.08.004