What is L-Carnitine? Sources, Dosage and Side Effects

1-What is L-Carnitine?

You may be asking what is L-carnitine or what is L-carnitine used for?

Is it just one of those nutrients that’s optional, or is it something that is important to supporting your health?

What is L-carnitine?

what is L Carnitine

There are a lot of misconceptions out there about what L-carnitine actually is.

Some people refer to it as an amino acid, but that’s technically incorrect.

It’s amazing how many sources out there have this wrong!

Yes, it is extremely similar in structure, but L-carnitine is actually a derivative of the amino acid, lysine.

What is L-carnitine used for?

In a nutshell, it plays a crucial role in the metabolism of fat, specifically the “long chain” fatty acids.

You see, fats and nutrients flow through our blood and this supplies our cells with “fuel.”

The mitochondria inside your cells use these supplied fats and sugars to make energy.

The short and medium chain fatty acids can enter the mitochondrial wall by themselves.

However, the long chain fats reportedly need L-carnitine in order to get inside.

So natural L-carnitine is said to be good for supporting the metabolism of these fats.

Where does L-carnitine come from?

There are two sources…

What we eat: Foods derived from animals contain carnitine. Unfortunately plant based sources contain only trace amounts.

Therefore, we strict vegan are hardly getting any L-carnitine through our diet.

Our body: Your body does produce carnitine naturally.

However, there is a vast amount of research that suggests our body’s production of carnitine declines with age.

This is why so many people in their 20’s, 30’s, 40’s and up are turning to L-carnitine supplements.

How are L-carnitine supplements used?

As a dietary supplement, the most common dosage on the market at this time appears to be 500mg, however some people use more or less depending on their age and circumstances (ask your doctor to find out what he recommends).

Many people report increased energy from using L-carnitine supplements, so for this reason some say it should avoided near the end of the day (just as you would avoid coffee late in the day).

One of the most popular versions of this supplement is alpha lipoic acid acetyl l-carnitine, because these two cellular nutrients combined are a powerful combination!

2-L-Carnitine Dosage

L Carnitine Dosage

As with any dietary supplement, please consult your doctor before taking L-carnitine.

Here are some typical L -arnitine dosages you can discuss with them:

Regular L-Carnitine Dosage: 

A typical recommended daily dosage is often L-carnitine 500 mg to 1,000 mg.

However it’s important to realize that L-carnitine is reportedly known for boosting energy levels, similar to caffeine.

Therefore it’s best to take before 3pm.

Also, some nutritionists recommend co-supplementing acetyl L carnitine and alpha lipoic acid, because they are said to work best together.

There have been dozens of clinical trials which suggest L-carnitine supplements may be very beneficial for a number of diseases and conditions, however the FDA has not evaluated any of these claims.[1]

It’s important to understand that L-carnitine is only a dietary supplement (not medicine) and cannot be used for the diagnosis, prevention, cure, or treatment of a disease.

L-Carnitine Dosage Weight Loss & Endurance

L Carnitine Dosage Weight Loss & Endurance

L-carnitine reportedly supports weight loss in two different ways:

Fat Burning: Carnitine assists in the burning of fat.

In fact, long chain fatty acids reportedly cannot be metabolized by your mitochondria without the aid of carnitine.

While it’s true our bodies make carnitine naturally, there’s less produced as we get older.

Furthermore, studies have suggested that L-carnitine deficiencies appear more prevalent in obese individuals.

Energy Support: When taking a supplemental L-carnitine dosage, one benefit is energy support.

This makes sense, since carnitine supports cell mitochondria in burning long chain fatty acids, turning them into energy.

Common sense also tells you that when a person has a healthy amount of energy, they’re more likely to be physically active, exercise, etc.

According to numerous online publications, the typical L-carnitine dosage for weight loss seems to be between 1 to 3 grams (1,000 to 3,000 mg) daily.

That being said, it seems to be more common to stick to the low end of that range.

L-Carnitine Dosage For Heart

Perhaps some of the most promising benefits of L-carnitine are those which are heart related.

There have been quite a few clinical studies which have shown very exciting results, especially for angina. 

Logically speaking, it makes sense since the heart is a muscle.

It has been said that muscles get up to seventy percent of their energy through burning fatty acids.

According to the University of Maryland Medical Center website, here are the adult recommended supplemental L-carnitine dosages for heart conditions:

• Heart failure & Angina: 1.5 to 2 grams daily
• Peripheral vascular: 2 to 4 grams per day
• Heart disease: 600 to 1,200 mg taken 3 times per day, or 750 mg taken 2 times per day

Of course as a reminder, L-carnitine is not medicine and should NOT be used to treat, cure, or prevent any of the above!

L-Carnitine Dosage For Brain

What’s unique about acetyl L-carnitine is that is has the ability to pass through the blood-brain barrier.

Proper energy metabolism for the brain is vital since it makes up 20% of your body’s energy consumption.

This is why research suggests L-carnitine supplements are beneficial for degenerative brain conditions.

The studies have had mixed results so far, so further research is needed.

However this isn’t stopping many doctors and nutritionists from recommending acetyl L-carnitine supplements for this purpose.

L-carnitine dosage for this use varies greatly.

There are some sources which recommend 250 mg to 300 mg to avoid possible side effects – such as nausea – which may occur in people who are sensitive to supplements.

However there have been other sources which recommend the typical dosage of L-carnitine 500 mg to 1,000 mg for supporting brain health.

Others have recommended even higher.

Consult your doctor to find out what would be best for you.

L-Carnitine Dosage For Other Conditions

According to the University of Maryland Medical Center resource (discussed above) here are some other L-carnitine dosages which were mentioned for specific conditions, but of course this should only be done under the direction of a physician:

 Overactive thyroid: 2 to 4 grams daily, divided in 2 to 4 doses
 Diabetic neuropathy: 3 grams daily
 Male infertility: 300 mg 1,000 mg, three times per day
 Chronic fatigue syndrome: 500 to 1,000 mg, 3 to 4 times per day

Important L-Carnitine Dosage Warning

With the fatty acids being metabolized by the cells more efficiently, there is naturally an increase in electron flow that goes along with it.

Inevitably, that may mean an increase in oxidative stress.

In order to help balance these things out, some say it’s best to combine acetyl L-carnitine & alpha lipoic acid (a powerful antioxidant and natural cofactor in mitochondrial enzymes).

So ideally a two-in-one alpha lipoic acid acetyl L-carnitine supplement.

3-L-Carnitine Side Effects

l carnitine side effects

L-carnitine is an extremely important nutrient which makes the digestion of certain fats possible.

But are there any L-carnitine side effects?

Well here are some important things you need to know before using this supplement…

Why is L-carnitine useful?

Some of the L-carnitine side effects actually make sense once you understand how it works.

Most of your body’s energy is made by the mitochondria inside your cells.

These mitochondria burn nutrients, turning them into energy.

Carnitine is an essential nutrient that helps your mitochondria absorb and metabolize certain types of fats.

The so called “long chain” fats cannot make it into the cells by themselves.

These types of fats need carnitine to transport them from the blood’s plasma into the cell.

Without carnitine acting as a transporter, reportedly this category of fats cannot be metabolized by the mitochondria.

What are the side effects of L-carnitine?

This process supports the burning of long chain fats.

Naturally, that can reportedly lead to higher cellular energy production.

Along with that, reportedly there may be certain side effects.

Some are common (like increased energy) while others seem to only affect certain groups of people with specific medical conditions.

Of course like almost any supplement or food, mild side effects like upset stomach or nausea are possible.

Some sources claim a fishy odor in the urine, sweat, and breath can occur, but that probably only occurs with a high dosage as that is a side effect which you don’t hear about.

Please note that dietary supplements (like L-carnitine) should never be used for the diagnosis, treatment, prevention, or cure of any disease or medical condition. None of the claims re-published on this site have been evaluated by the FDA. Nor does this site itself make any claims to L carntine – all of the alleged information presented here has been gathered from various sources.

Here are various tips for taking L-carnitine supplements which have been published on other websites:

Don’t take them late in the day.

Because L-carnitine is known for boosting energy levels, it’s important to avoid them later in the day (just like caffeine).

The notable nutritionist Robert Crayon, who dedicated several years researching carnitine, advises against taking it after 3pm since doing so may make it difficult to fall asleep a few hours later.

This is the most common L-carnitine side effect, but obviously it can be easily controlled by simply taking them early on in the day.

Have cancer or HIV? 

Then you should avoid this supplement unless your doctor tells you otherwise.

This is because one of the L-carnitine side effects is that it may interfere with medicines used in treating these diseases.

Have a history of seizures? 

Then you should not take L-carnitine supplements, unless specifically directed by your doctor.

L-carnitine supplements have been known to increase the frequency and/or seriousness of seizures for those that have a history of them.

It has been theorized that the reason for this may be because L carnitine causes increased cellular activity and energy, which in turn may trigger the “switch” which causes an episode.

Are you pregnant? 

There is not enough known as to whether there are any L-carnitine side effects for women who are expecting.

Therefore if that’s you, it would be best to be safe and avoid L-carnitine unless directed by your doctor.

Under-active thyroid? 

There is some research which may suggest L-carnitine supplements may not be a good idea for those suffering from this condition.

It is suspected that an L carnitine side effect is  that it might possibly interfere with this gland’s hormone.

Is L-carnitine safe to take?

This is a naturally occurring nutrient that we’ve known about for over a hundred years and is likely safe, according to numerous sources.

There have been many clinical trials conducted and it appears to greatly support the health of our heart, brain, muscles, the burning of fat, and your energy.

Our bodies produce less as we age, which is why deficiency is common.

L-carnitine has been coined the anti-aging supplement by both scientists and consumers.

For best results, it has been recommended to take alpha lipoic acid and L-carnitine supplements together as they compliment each other.

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