In this article I will elaborate on the health benefits of L-Carnitine.
You will learn how to lose fat and improve your mood with this nootropic as well as side effects and contraindications of use.
CAUTION: Medical Disclaimer
Table of Contents
My experience with Carnitine
Carnitine is not a new supplement for me since I have been using it since I was 22. It is an amazing supplement and while it was originally marketed for fat loss, it is also fantastic for cardiovascular health, insulin sensitivity and overall hormonal health.
In my experience the fat loss effect ceases after 2-3 weeks but this is mostly because of homeostasis happening in the body. Upping the dose will ensure that you keep getting results.
Just like with creatine, there are responders and non-responders (see study) which explains why people either love it or hate it.
A few years ago, I switched to Acetyl-l-Carnitine and found it to work even better. It gave me an amazing focus (since it is also a nootropic supplement that enhances cognitive processes), I was killing it in the gym, could handle stress better and slept better at night.
Turns out that in some people it can also give a stimulative effect but the mechanism on how that works is not currently known. I highly recommend Carnitine for improving health, body composition and performance in the gym.
What is Carnitine?
L-Carnitine is a naturally occurring amino acid made in the liver and kidneys. It is stored in the heart, brain, skeletal muscles and sperm.
It was initially introduced to the bodybuilding world for its fat burning properties. L-Carnitine increases the mitochondria’s potential for fat loss – up to a certain degree and under certain conditions (i.e. via ways of exercise when fat cells get triggered to be burned). However L-Carnitine in reality does not actually burn fat directly but does so indirectly by increasing energy levels in the body. This in turn increases activity, improves exercise and in the long run promotes healthy fat loss.
Also, when the mitochondria are stimulated for fat loss, they tend to become more bulletproof against aging and exercise. This is because of L-Carnitine’s antioxidant qualities as it can fight off free radicals and reduce their damage in the human body.
Since it is found in the heart, it has been used in medicine for certain heart-related conditions.
While L-Carnitine can be made in the body, there are certain conditions and/or medications that stop the body from making enough carnitine, cause carnitine depletion or block its efficient transportation to the appropriate tissues. This is when supplementation comes in handy.
Carnitine benefits include:
- Supporting insulin resistance by triggering fat acids and transporting them to the cells for burning and production of ATP. While it is not primarily responsible for fat loss, it can help to lose fat by restoring the body’s fat loss potential.
- Supporting heart health after heart attacks by supporting the muscles of the heart. (L-Carnitine and propionyl-L-Carnitine)
- Stabilizing angina and helps people to exercise without chest pain. (L-Carnitine),
- Reducing symptoms of heart failure. (L-Carnitine and propionyl-L-Carnitine)
- Improving L-Carnitine deficiency in people with angina, intermittent claudication or people who take anti-seizure medication or have kidney problems and require hemodialysis.
- Improving symptoms of hyperthyroidism (rapid or pounding heartbeat, nervousness and weakness).
- Countering male infertility by increasing sperm count when infertility is caused by inflammation of the prostate and seminal vesicles. It does not increase testosterone but it can protect its production during times of stress (as an antioxidant).
- Partially improving sports performance by assisting with glycogen depletion (it is partially converted to creatine so it can replenish ADP energy stores). It also removes muscle lactate and other waste products from cells thus protecting key organs from disease. (L-Carnitine and propionyl-L-Carnitine)
Acetyl-L-Carnitine has all the above benefits plus:
- Is more bioavailable than other forms and has stronger antioxidant properties,
- Is a brain and neuro protector as well as a brain booster. This means increased alertness and support for neuron growth. It can actually cross the blood-brain barrier and once it reaches the brain it converts to Acetyl-COA, which binds with choline and turns into Acetylcholine which can support memory, focus, mental alertness and other cognitive functions.
Because of its latter attribute it is also used in studies in Alzheimer’s and other brain conditions.
When and how to take it
There are 5 forms of carnitine:
- L-Carnitine and its converted forms,
- L-Carnitine L-Tartrate (LCLT),
- Propionyl-L-carnitine (which is Glycine-bound),
- Acetyl-L-Carnitine (ALCAR),
L-Carnitine and Propionyl-L-Carnitine are mostly used for their heart protective benefits, while ALCAR is used mostly for brain health and fat loss.
The 5th form (D-Carnitine) should be avoided at all costs since it can interfere with the natural L-Carnitine form and cause toxicity and other unwanted side effects.
When used for treating cardiac and other serious conditions, L-Carnitine should be taken by prescription only. Do not take L-Carnitine supplements without consulting your doctor first.
To protect your body from insulin resistance you will need to combine L-Carnitine with its precursor – Lysine.
Just like with all amino acid forms, make sure to use only the L- version of any carnitine since anything else will be synthetic and therefore toxic.
Safety and side effects
L-carnitine is considered to be LIKELY SAFE when taken orally in recommended doses (under 5gr) by healthy people.
Reported side effects include:
- Increased appetite,
- Fishy body odor and breath,
- Skin rash,
- Stomach upset,
Also in some cases, its slightly fishy odor can be detected in sweat and urine.
Special Precautions & Warnings:
There is not enough information regarding the safety of L-Carnitine so avoid using them during pregnancy.
According to WebMD, taking L-Carnitine while breastfeeding has been deemed as POSSIBLY SAFE when taken in recommended amounts. However because the effects of taking Carnitine in large amounts are currently not known this practice is not advised and should be avoided.
Do not give L-Carnitine supplements to a child unless instructed by a doctor.
Contraindications or interactions with other medication/substances:
Consult with your doctor before using this supplement especially if you have any of the following conditions or take the following medication/substances:
- Underactive thyroid (hypothyroidism) as L-carnitine can worsen hypothyroidism symptoms.
- Seizures as L-carnitine appears to increase the risk of seizures in people with seizure history.
- Peripheral vascular disease,
- High blood pressure,
- Alcohol induced Liver disease (cirrhosis),
- Kidney disease,
- Anticoagulants/blood thinners: When taken with L-Carnitine they may increase their effects and increase the risk of bleeding.
- Thyroid hormone: When taken with L-Carnitine it may decrease its effectiveness by stopping the thyroid hormone to enter the cells.
- Anti-seizure medication: When taken with L-carnitine it may decrease their effectiveness.
Do I need to cycle off?
Cycling is not required but I always recommend taking 1 month off after using it for 5-6 months.
Over the past 20 years I have experimented with literally hundreds of herbs, supplements (and other natural products) and was finally able to discover the right doses for amazing results.
If you wish to learn more about the dosages that I use with my clients for different purposes (better health, hormonal balance, stress management, testosterone boost and more) or how I combine this herb/supp with others, leave a comment below or reach out to me for a consultation through the “Hire me” link.
L-Carnitine maybe just an amino acid but it has countless health benefits when used as part of a complete exercise and nutrition program.I personally recommend it for improving body composition, cognitive processes, mood, supporting testosterone and hormonal levels.
I hope you enjoyed this article as much as I did writing it. Putting together this article took a bit of time but it will only take you a second to click on the Share buttons below and show your support to this blog.
Also if you have any comments or questions, feel free to leave a comment and I will get back to you as soon as possible. Thanks!
by Nick Sigma
CWC, EH, E-YRT200
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- Improvement of sperm quality after micronutrient supplementation
- Mike Mahler’s optimization course.