If the name has you craving some juicy carne,  you’re actually on the right track. L-carnitine is an amino acid  derivative found in meat and animal products. Lucky for the vegans in  the house, our bodies can also make it.

Whether you know it or not, you’re already familiar with L-carnitine. Your body relies on it every day. It’s responsible for fast-tracking fatty acids to your mitochondria, which burn the fat into energy. L-carnitine is basically the low-key conveyor belt sending your fat to the incinerator.

Some signs you’re deficient include:

  • decreased muscle tone or weak muscles
  • fatigue
  • irritability
  • symptoms of low blood sugar

These  symptoms are similar to those of many other conditions, so talk to your  healthcare provider before you jump on the supplement train.

The carnitine squad

There  are several types of carnitine. L-carnitine kinda steals the spotlight  since it’s the one in red meat and most supplements.

Meet the others:

  • D-carnitine. If L-carnitine is a fat-busting superhero, D-carnitine is its lazier twin. This inactive form might even restrict your body’s capacity to absorb more useful members of the carnitine family.
  • Acetyl-L-carnitine. Called ALC for short, this is the carnitine voted most likely to boost your brain power. The jury’s still out, but some research suggests it’s a good supplement for folks with neurodegenerative diseases like Alzheimer’s disease or Parkinson’s disease.
  • Propionyl-L-carnitine. If you’re dealing with circulation issues — anything from high blood  pressure to erectile dysfunction — this is the carnitine for you. One  study suggests it improves blood flow by increasing nitric oxide levels.
  • L-carnitine L-tartrate. Scientific evidence behind this common sports supplement is mixed. Some studies have shown that it speeds up muscle recovery, while others suggest it won’t do much to improve performance.

Bottom line:

ALC  and L-carnitine are probably your best bets for a general supplement.  But it’s also important to take a look at the different types in  relation to your #goals.

Here’s what going down in your body RN

Almost all the L-carnitine in your body is stored in your muscles. The rest is chillin’ in your liver and bloodstream.

Right  now your L-carnitine stores are busy keeping your mitochondria, aka  your cells’ engines, fueled up. And since amino acids play a lot of  roles, L-carnitine also picks up toxins and dumps them outside the cell  walls. What a gem.

Bottom line:

L-carnitine  lives in your muscles, where it shovels fatty acids into cells so they  can be burned for energy. Your body makes L-carnitine, but you can boost  your level through food or supplements.

The tea on slimming down with L-carnitine

Popping  L-carnitine might sound like a pretty convenient way drop a little  weight. But let’s keep it 100: Sure, L-carnitine is responsible for  shoveling fatty acids into the furnace, but that’s just a teeny, tiny  part of the metabolic process.

Despite claims from supplement companies, there just isn’t much medical evidence of L-carnitine’s weight loss superpowers.

Here’s what we know:

  • A 30-day study of 32 fat cats (yes, really) revealed that the kitties who took  L-carnitine supplements had a dramatically higher resting energy  expenditure (REE) and fat-burning capacity than the cats who didn’t get  any. But in the end, the supplemented cats didn’t lose more weight than  the others.
  • In a review of nine studies of people with obesity, researchers found that  participants taking L-carnitine lost about 2.9 more pounds (1.3 more  kilograms) than those who didn’t.
  • While L-carnitine supplements  certainly won’t hurt your efforts to slim down, burning fat at the  cellular level won’t make a difference without diet and exercise  changes.

What about brain-boosting power?

If  you’re generally healthy, you probably already produce enough  L-carnitine. But your biological clock wreaks havoc on more than  baby-making and crow’s feet. Age can cut into your L-carnitine stores (so can diabetes and genetic conditions).

Studies on animals have suggested that L-carnitine can boost function in aging brains and possibly protect brain cells from damage.

Unfortunately, there isn’t much research yet on whether taking L-carnitine boosts brain power in younger, healthier people.

Any love for the heart?

Let’s start with the good news: A 2013 review found that L-carnitine helped heart attack patients recover quickly.  Since all the carnitines prefer to do their work inside muscle tissue,  it makes sense that their presence is good for the heart.

But that same year, a study in mice found that L-carnitine in red meat might increase levels of trimethylamine-N-oxide (TMAO), which could cause clogged arteries.

What gives? A 2004 review of older medical research suggested that L-carnitine does the most for people who’ve already had a  heart attack. The jury’s still out on exactly how it could help or harm  healthy hearts.

Wanna get those gym #gainz?

Some  research says L-carnitine supports workout #goals in the long term.  Typically, L-carnitine is a slow burn. Don’t expect it to kick in  overnight like caffeine or creatine. Stick with it and you might be running harder, better, faster, stronger in a few months.

On the flip side, a small study of professional athletes found that those who received 3 to 4 grams of  L-carnitine immediately before a workout had better endurance.

Here’s how L-carnitine might improve your workouts over the long haul:

  • Endurance. It could help your blood flow and keep your heart rate down during intense exercise.
  • Muscle soreness. A 1996 study suggested that L-carnitine could reduce delayed-onset muscle soreness (aka DOMS).
  • Oxygen supply. A 2005 study on mice found that L-carnitine might speed up red blood cell production, which keeps oxygen flowing freely to the muscles.

Any perks for the peeps with type 2 diabetes?

Living with type 2 diabetes takes a whole lotta discipline. But there’s evidence that taking L-carnitine might alleviate some symptoms and risks.

Some research suggests acetyl-L-carnitine (ALC) dials down nerve pain and weakness caused by type 2 diabetes. A 2005 study suggested L-carnitine supplements could also lower blood sugar.

There  isn’t much new research on links between type 2 diabetes and  L-carnitine (weight loss studies get all the love, amiright?). But the  bottom line is that if you’re dosing properly and checking with your  doctor, L-carnitine is way more likely to help than to hurt.

Safety PSA

L-carnitine is technically FDA-approved for just one use: treating carnitine deficiency. But doses of less than 3 grams a day seem safe for pretty much anyone. Taking too much (2 to 3 grams,  depending on your body) can cause mild side effects, including:

  • nausea
  • stomach cramps
  • “fishy” body odor

And, as we mentioned, a 2013 study in mice found that L-carnitine in red meat might contribute to clogged arteries, although more research is needed.


More  medical studies are needed, but up to 2 grams a day seems safe for most  people. One animal study suggested that L-carnitine supplements could  raise your risk of blocked arteries.

To supplement or not to supplement…

There’s no “one size fits most” answer for whether or not you should add a bottle of L-carnitine to your medicine cabinet.

Technically,  your body can whip up L-carnitine without help, thank you very much.  The main things to consider are your diet and whether your body is  healthy enough to create what it needs.

The folks most likely to benefit from supplementation:

  • Vegetarians and vegans have a higher risk of L-carnitine deficiency since they don’t eat animal products.
  • Older adults might benefit from L-carnitine supplements since research shows your levels go down as you get older.
  • People with cirrhosis and kidney disease often have low L-carnitine levels. A supplement can help with their overall wellness.

If  you still wanna give L-carnitine a whirl, remember to research the  specific carnitine type that’s right for your goals. Chatting with your  doctor isn’t a bad idea either.

Get the right dose

Most  people supplement with 500 to 2,000 milligrams of L-carnitine per day.  Two grams (2,000 milligrams) seems to be the sweet spot for long-term  effectiveness without health risks.

Pick your poison

Pill-popping  isn’t the only way to give yourself a little L-carnitine love. You can  find it in foods, liquids, powders, and even injections.

While the  best way to score nutrients is through diet and a healthy lifestyle,  supplements can help. If you’re concerned about mixing meds, it’s always  a good idea to check with your doctor.

Meat and dairy

Your body absorbs L-carnitine from food sources more quickly than from supplements. Sneak in some L-carnitine with a  3-ounce serving (about the size of your palm) of these meats:

  • Beef: 81 milligrams
  • Pork: 24 milligrams
  • Fish: 5 milligrams
  • Chicken: 3 milligrams

Meat is your best bet, but other animal products deliver itty-bitty doses of L-carnitine too:

  • Ice cream (½ cup): 3 milligrams
  • Cheddar cheese (2 ounces): 2 milligrams
  • Milk (8 ounces): 8 milligrams


Mix a concentrated liquid supplement into your morning glass of water or OJ if you’re not a fan of  swallowing pills. Bonus: You can try ALL the flavors! Start slow, with a  1,000-milligram dose per day.

Cost is the main drawback to liquid supplements. You’ll get more bang for your buck with powder or pill forms.


Powdered L-carnitine supplements work well for those who already whip up a protein shake or smoothie in  the morning. Add a scoop (1,000 milligrams) along with your collagen or  protein powder.

There’s not much difference in cost between powder and pills, so pick whatever strikes your fancy.


Injections and IV doses of L-carnitine are best left up to the pros. In a 2014 study of people who had an L-carnitine deficiency, switching from pills to IV therapy had a positive effect on cholesterol levels.

If  you think your body is L-carnitine deficient, it’s best to talk to your  healthcare provider about treatment options and sources.


Most medical research on humans taking L-carnitine has involved pills,  so sticking to this supplement form gives you the highest chance of  getting good results. Vegetarian capsules are available, so it’s a #win  for those who prefer their L-carnitine without the carne.

Bottom line

L-carnitine  is known as a fat-burner because that’s what it does on the cellular  level. Studies on leveraging that for weight loss have been mixed.

Of  all the different carnitine types, L-carnitine and acetyl-L-carnitine  show the most promise. There’s evidence that these forms are good for  your brain and heart and even for disease prevention.

Supplements  are a good idea for people with naturally low L-carnitine levels: older  adults, vegans, and vegetarians. But it’s best to chat with your doctor  before taking any new supplement.

Source : https://greatist.com/health/l-carnitine#how-to-get-it