| Title |
Determination of the safety of leucine supplementation in healthy elderly men
|
|---|---|
| Published in |
Amino Acids, April 2016
|
| DOI | 10.1007/s00726-016-2241-0 |
| Pubmed ID | |
| Authors |
Betina Rasmussen, Erin Gilbert, Abrar Turki, Kenneth Madden, Rajavel Elango |
| Abstract |
Leucine, a branched-chain amino acid (BCAA), has been shown to stimulate muscle protein synthesis, and thus has been proposed to prevent age-related muscle atrophy (sarcopenia). Therefore, leucine supplementation may have potential benefits in elderly populations to preserve muscle mass. The tolerable upper intake level (UL) for leucine intake in young men has recently been determined to be 500 mg kg(-1) day(-1), and increases in blood ammonia concentrations were seen at intake levels above 500 mg kg(-1) day(-1); the UL for leucine in elderly is unknown. The objective of the current study was to determine the safety of leucine supplementation in healthy elderly men. Six healthy elderly men (72.2 ± 3.5 years) received graded stepwise increases in leucine intakes ranging from 50 to 750 mg kg(-1) day(-1), on eight separate study days. Plasma and urinary biochemical variables, including blood ammonia, and an oral primed-continuous protocol of L-1-(13)C-Leucine was performed. Blood ammonia concentrations above normal values (35 µmol/L) were observed at leucine intakes >550 mg kg(-1) day(-1). Leucine oxidation measured as a F(13)CO2 (rate of label tracer oxidation) increased with increasing leucine intakes and started to plateau after 450 mg kg(-1) day(-1). Two-phased linear regression analysis of the F(13)CO2 data revealed a breakpoint of 431 mg kg(-1) day(-1) (R (2) = 0.73), suggesting that the upper limit to oxidize leucine was reached at that point. Taking the data together the upper limit for leucine intake in healthy elderly could be set similar to young men at 500 mg kg(-1) day(-1) or ~35 g/day for an individual weighing 70 kg. |
X Demographics
The data shown below were collected from the profiles of 9 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Canada | 3 | 33% |
| United Kingdom | 2 | 22% |
| Australia | 1 | 11% |
| Ireland | 1 | 11% |
| Unknown | 2 | 22% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 5 | 56% |
| Practitioners (doctors, other healthcare professionals) | 2 | 22% |
| Scientists | 2 | 22% |
Mendeley readers
The data shown below were compiled from readership statistics for 67 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United Kingdom | 1 | 1% |
| Switzerland | 1 | 1% |
| Unknown | 65 | 97% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 12 | 18% |
| Student > Master | 9 | 13% |
| Researcher | 9 | 13% |
| Student > Bachelor | 5 | 7% |
| Student > Doctoral Student | 4 | 6% |
| Other | 6 | 9% |
| Unknown | 22 | 33% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 10 | 15% |
| Sports and Recreations | 9 | 13% |
| Biochemistry, Genetics and Molecular Biology | 5 | 7% |
| Nursing and Health Professions | 5 | 7% |
| Agricultural and Biological Sciences | 4 | 6% |
| Other | 10 | 15% |
| Unknown | 24 | 36% |
Attention Score in Context
This research output has an Altmetric Attention Score of 9. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 04 April 2023.
All research outputs
#3,869,647
of 23,515,785 outputs
Outputs from Amino Acids
#230
of 1,539 outputs
Outputs of similar age
#59,810
of 300,074 outputs
Outputs of similar age from Amino Acids
#6
of 35 outputs
Altmetric has tracked 23,515,785 research outputs across all sources so far. Compared to these this one has done well and is in the 83rd percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,539 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 6.8. This one has done well, scoring higher than 85% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 300,074 tracked outputs that were published within six weeks on either side of this one in any source. This one has done well, scoring higher than 80% of its contemporaries.
We're also able to compare this research output to 35 others from the same source and published within six weeks on either side of this one. This one has done well, scoring higher than 82% of its contemporaries.