L-Carnitine and Improved Quality of Life

Research synthesisLow evidenceSmall effect5 studies · 3 beneficial · 2 neutral · 0 harmful

Across 5 studies (3 beneficial, 2 neutral), L-carnitine shows mixed evidence for improving quality of life, with predominantly small effects. Effects were observed in clinical populations over a median study duration of 77 days. The most-studied dose was 2 g/day in one study, but doses varied widely.

Studied populations: Clinical populations with specific conditions: liver cirrhosis, migraine, benign prostatic hyperplasia, hemodialysis in children, chronic obstructive pulmonary disease

Caveats: The highest-quality RCT (n=150) found no significant between-group difference in quality of life, despite within-group improvement. One beneficial study is a protocol with no results yet. The evidence base is limited by small sample sizes and mixed results. Clinical significance of observed effects is uncertain. Most studies were in clinical populations, so generalizability to healthy individuals is unclear.

Generated Jul 15, 2026

Doses used in studies

g/day: 2 (median 2, IQR 2–2) — 1 study
mg/day: 500 (median 500, IQR 500–500) — 1 study
mg/kg/day: 50 (median 50, IQR 50–50) — 1 study

Time to effect

Median: 11 weeks · IQR 9.5 weeks–3.5 months · Range 8 weeks–5.6 months — Reported in 4 of 5 studies

Safety in these studies

Overall tolerabilityReported
we propose broader research and implementation of this nutraceutical agent as an effective, inexpensive, and safe adjuvant therapeutic for the long-term management of COPD patients
from: Targeting Skeletal Muscle Dysfunction With L-Carnitine for the Treatment of Patients With

5 of 5 papersPopulation:

Effect of L-carnitine on quality of life in covert hepatic encephalopathy: a randomized, double-blind, placebo-controlled study.
- 2022-07-01
- RCT · n = 150
- The Korean journal of internal medicine 37(4)
- - Eileen L Yoon
  - Sang Bong Ahn
  - Dae Won Jun
  - Yong Kyun Cho
  - Do Seon Song
  - Jae Yoon Jeong
  - Hee Yeon Kim
  - Young Kul Jung
  - Myeong Jun Song
  - Sung Eun Kim
  - Hyoung Su Kim
  - Soung Won Jeong
  - Sang Gyune Kim
  - Tae Hee Lee
- PubMed: 35526858
- DOI: 10.3904/kjim.2021.338
7 Insights on
- Improved Quality of Life
- High evidence
- Large Human Trial
- Clinical
total SF-36 score significantly improved in the L-carnitine group after 24 weeks ... however, these values were comparable between the two groups.
Effect
Neutral
Effect size
Small
Significant
No
Dose
2 g/day
Investigating the effects of co-supplementation with alpha-linolenic acid and L-carnitine on inflammatory status, oxidative stress, clinical symptoms, mental health and quality of life in women with migraine: a protocol for a randomized, triple-blind, placebo-controlled trial.
- 2024-10-08
- RCT · n = 80
- Trials 25(1)
- - Sahar Golpour-Hamedani
  - Mohammad Bagherniy
  - Fariborz Khorvash
  - Awat Feizi
  - Manoj Sharma
  - Gholamreza Askari
- PubMed: 39380085
- DOI: 10.1186/s13063-024-08500-3
11 Insights on
- Improved Quality of Life
- High evidence
- Clinical
Secondary outcomes include mental health, sleep quality, and quality of life (QOL)
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Dose
500 mg/day
Effects of L-Carnitine and Coenzyme Q10 Supplementation on Lower Urinary Tract Symptoms in Men with Benign Prostatic Hyperplasia: A Randomized, Controlled, Clinical Trial.
- 2023-12-17
- RCT
- Nutrition and cancer 76(2)
- - Mahsa Norouzi
  - Sepideh Mahboobi
  - Mohammad Hassan Eftekhari
  - Mehdi Salehipour
  - Haleh Ghaem
  - Ali Mirzakhanlouei
  - Mohammad Ali Mohsenpour
- PubMed: 38105612
- DOI: 10.1080/01635581.2023.2295578
5 Insights on
- Improved Quality of Life
- High evidence
- Clinical
However, there were no significant between-group differences in IPSS (p = 0.503), QoL scores (p = 0.339), and PSA levels (p = 0.482).
Effect
Neutral
Effect size
Small
Significant
No
Effect of L-Carnitine Supplementation on Inflammatory Markers and Serum Glucose in Hemodialysis Children: A Randomized, Placebo-Controlled Clinical Trial.
- 2022-03
- RCT · n = 12
- Journal of renal nutrition : the official journal of the Council on Renal Nutrition of the National Kidney Foundation 32(2)
- - Fatemeh Hamedi-Kalajahi
  - Hossein Imani
  - SayedYousef Mojtahedi
  - Sakineh Shabbidar
- PubMed: 34740538
- DOI: 10.1053/j.jrn.2021.03.009
5 Insights on
- Improved Quality of Life
- High evidence
- Clinical
raised ... Pediatrics Quality of Life scores compared with the placebo.
Effect
Beneficial
Effect size
Small
Significant
Yes
Dose
50 mg/kg/day
Targeting Skeletal Muscle Dysfunction With L-Carnitine for the Treatment of Patients With Chronic Obstructive Pulmonary Disease.
- 2023
- Review
- In vivo (Athens, Greece) 37(4)
- - Ba X Hoang
  - B O Han
  - William H Fang
  - Anh K Nguyen
  - David G Shaw
  - Cuong Hoang
  - Hau D Tran
- PubMed: 37369514
- DOI: 10.21873/invivo.13224
2 Insights on
- Improved Quality of Life
- Low evidence
This review shows how skeletal muscle dysfunction and metabolic abnormalities contribute significantly to COPD patients' symptoms, functional activities, quality of life, and overall disease outcomes. Based on the clinical evidence of L-carnitine and derivatives as metabolic and muscle bioenergetic enhancers, we propose broader research and implementation of this nutraceutical agent as an effective, inexpensive, and safe adjuvant therapeutic for the long-term management of COPD patients.
Effect
Beneficial
Effect size
Small
Significant
Yes

L-Carnitine and Improved Quality of Life

Effect of L-carnitine on quality of life in covert hepatic encephalopathy: a randomized, double-blind, placebo-controlled study.

Investigating the effects of co-supplementation with alpha-linolenic acid and L-carnitine on inflammatory status, oxidative stress, clinical symptoms, mental health and quality of life in women with migraine: a protocol for a randomized, triple-blind, placebo-controlled trial.

Effects of L-Carnitine and Coenzyme Q10 Supplementation on Lower Urinary Tract Symptoms in Men with Benign Prostatic Hyperplasia: A Randomized, Controlled, Clinical Trial.

Effect of L-Carnitine Supplementation on Inflammatory Markers and Serum Glucose in Hemodialysis Children: A Randomized, Placebo-Controlled Clinical Trial.

Targeting Skeletal Muscle Dysfunction With L-Carnitine for the Treatment of Patients With Chronic Obstructive Pulmonary Disease.