L-Carnitine vs Acetyl L-Carnitine: Which one to use?

You’ve read about L-carnitine and acetyl L-carnitine (ALCAR). How do you know which one to use?

 What are they?

L-carnitine is an amino acid which can be created from lysine and methionine. It is only made in the liver, kidneys, and brain. Acetyl L-carnitine is L-carnitine that has been modified with an acetyl group.

 L-carnitine

L-carnitine is useful to transport long-chain fatty acids across the inner membrane of the mitochondria, where they can be oxidized for energy. Using fats for energy is a way to provide the cell with energy without raising insulin levels. L-carnitine facilitates this process.

Long-chain fatty acids cannot cross the mitochondrial membrane without L-carnitine. L-carnitine shuttles the long-chain fatty acid into the mitochondria.  

Use this when:

 You want the horse to burn long-chain fatty acids instead of glucose to help keep insulin levels down.

 You want to provide energy from fatty acids for hard work or endurance.

 You want to aid in the recovery from hard work.

 Your horse is on the SGLT2 inhibitors (the *-flozin
drugs). The protocol is discussed here.

 You want to help your horse’s energy utilization that has PSSM.

 Acetyl L-carnitine (ALCAR)

ALCAR is l-carnitine with an added acetyl group to it. The acetyl group modifies its functions.

Functions affecting the nervous system

The brain and spinal cord

 ALCAR may be neuroprotective.

 ALCAR may modulate neurotransmitters that are responsible for improved learning and attention, motivation, and reduction in the perception of pain.

Peripheral nervous system

 Improves functioning of the neuro-muscular junction

 May modulate transmission of the pain response

 May improve the clinical signs of neuropathic pain.

Functions affecting cellular response

 ALCAR promotes the creation of new mitochondria.

 It also is implicated in the repair and replacement of old or damaged mitochondria.

 ALCAR is an anti-oxidant and anti-inflammatory.

 ALCAR may improve insulin sensitivity.

 In a nutshell:

 Consider L-carnitine when you want to use long-chain fatty acids for energy for muscle metabolism, instead of glucose.

 Consider acetyl L-carnitine when

 you want to increase the number of mitochondria in the cells,

 you want to improve neurotransmission,

 you want to address neuropathic pain.

Do you have a special photo or story that you’d like to share? Email to sales@mybesthorse.com

Disclaimer: Statements regarding dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease or health condition.

©Joan Kulifay, MSc. 2025

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