Carnitine and Fatigue

L-carnitine is important for energy production, and a study found that supplementing with l-carnitine reduced symptoms of fatigue in some people with hypothyroidism (An et al., 2016).  The dosage used in the study was 990 mg twice a day for twelve weeks.  A few people experienced minor side effects like nausea and discomfort. 

 

When your doctor wants to test your TSH to see if it is in the normal range while you are on a prescription, you should be aware that your levels will be highest first thing in the morning then gradually go down; and a study found levels to drop by as much as 30% due to eating breakfast (Dong et al., 2022).  This is why we recommend that you get to the lab first thing in the morning and not eat anything before the test in order to get the most accurate reading of your actual levels.  You can bring a snack to eat on the way home.  Another option is an at-home finger prick test you can do as soon as you wake up.  This will save you in time and transportation cost in addition to the convenience.  Let me know if you want me to help you order the at-home kit. 

 

 

References:

 

An, J. H., Kim, Y. J., Kim, K. J., Kim, S. H., Kim, N. H., Kim, H. Y., Kim, N. H., Choi, K. M., Baik, S. H., Choi, D. S., & Kim, S. G. (2016). L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double-blind, placebo-controlled trial. Endocrine Journal, 63(10), 885–895. 

 

ClinicalTrials.gov. National Library of Medicine (U.S.). (2013). Effects of L-carnitine on Hypothyroidism. Identifier NCT01769157.

 

Dong, A., Huang, Y., Huang, Y., & Jia, B. (2022). Effects of calorie intake and sampling time on thyroid stimulating hormone concentration. BMC Endocrine Disorders, 22(1). 

 

Naik, H., Shao, S., Tran, K. C., Wong, A. W., Russell, J. A., Khor, E., Nacul, L., McKay, R. J., Carlsten, C., Ryerson, C. J., & Levin, A. (2022). Evaluating fatigue in patients recovering from COVID-19: validation of the fatigue severity scale and single item screening questions. Health & Quality of Life Outcomes, 20(1), 1–9.