The Benefit of L-Carnitine

WHAT IS IT AND WHAT DOES IT DO

L-carnitine is an amino-acid like nutrient that is naturally produced in the body. L-carnitines main role in the body is transporting long-chain fatty acids into the cells mitochondria where is it burned for energy¹.

More than 95% of the body’s L-carnitine is stored in the muscle with small amounts found in your liver and blood².

Your body will produce L-carnitine from the amino acids lysine and methionine, but requires plenty of Vitamin C to do so³. You can also get a certain amount of L-carnitine from your diet by eating animal products such as red meat and fish⁴.

For vegans, or people who cannot produce enough L-carnitine naturally, supplementing with L-carnitine is essential.

For athletes, L-carnitine supplementation boosts the body’s own production and may lead to increases in muscle performance, fat burning and reductions on fatigue⁵.

WHY WOULD IT POSITIVELY AFFECT PERFORMANCE

As carnitine is responsible for moving fatty acid into the cells, supplementing with carnitine has been studied as a performance enhancer on the premise that increasing muscle carnitine content will increase the utilisation of fat during exercise and decrease muscle glycogen depletion⁶.

Indeed, research found that supplementing with 2grams of L-carnitine + 80g carbohydrate twice daily for 24 weeks saw an increase in fatty acid utilisation, substantially reduced lactate production and an increased work output of 11% from baseline when compared to no change in the control group⁷. Further to this it has been suggested that supplementing with 2g daily for 4-weeks has been associated with an improvement in VO2max in long distance runners⁸.

Supplementing with L-carnitine may also play a role in recovery from strenuous exercise. Ingesting between 2-4g/day has been shown to reduce pain, tenderness and exercised-induced muscle damage following an intense period of training.^9,10

To note:
When taking L-carnitine it is important to remember these two things:

For performance, supplementing L-carnitine and carbohydrate together has been shown to increase carnitine content in skeletal muscle and maximise the benefits you get from the supplement¹¹.
The benefits of L-carnitine may be more indirect and take time to appear. It is suggested that consistent use over a 4–6-month period is needed for the fat oxidation, fatigue reduction and recovery benefits to kick in.

CAN IT HELP WITH WEIGHT LOSS

Whilst you might think that ‘burning’ more fat would equal more fat loss – this isn’t always the case, and the research into whether L-carnitine helps with fat loss is mixed.

In an 8-week study there was no difference between those who took L-carnitine and those who did not¹². However, a recent meta-analysis¹³ [study of studies] concluded that:

“L-carnitine supplementation reduced body weight, BMI and fat mass…with larger reductions shown in those who were overweight/obese compared to those with normal BMI”

What is key to note, is that alone L-carnitine won’t help you lose body fat, this must be done together with a healthy balanced diet and lifestyle.

HOW MUCH TO TAKE AND WHEN

There are various forms of carnitine supplementation available.

Acetyl-L-carnitine: 600-2500mg/day
The best for brain health and function
L-carnitine L-tartrate: 1000-4000mg/day
The most effective for exercise performance

If you plan to get the most from your workout then supplementing with L-carnitine [+ carbohydrate] one hour prior to exercise is the best idea. If you are looking to take advantage of the benefits on recovery and weight loss, then supplementing after exercise can also be effective.

BOTTOM LINE

There is still much more for us to learn about L-carnitine, but if you are serious about taking it, make sure you are making this a long-term change, as in the short term its likely you won’t see much change. L-carnitine can be found in PhD’s Diet Whey, Diet Whey Meal, Burn and Lean Degree.

References

Written by Sean Aspinall