Facts about Carnitine Deficiency: Signs, Symptoms, Causes, Treatment, and Prevention

Facts about Carnitine Deficiency: Signs, Symptoms, Causes, Treatment, and Prevention

Facts about Carnitine Deficiency: Signs, Symptoms, Causes, Treatment, and Prevention

Carnitine deficiency is a rare metabolic disorder characterized as the body's inability to process fats into energy properly. This condition affects thousands of people, particularly children. If you suspect that you are suffering from this condition, have yourself checked by a professional. Want to know what carnitine deficiency is and what signs to watch out for? Continue reading below:  

Facts about Carnitine Deficiency

Carnitine is a type of amino acid found in nearly all animal tissues and organisms. The human body produces carnitine naturally by synthesizing lysine side chains, a process that enables the body to process and convert fat to fuel. Carnitine contributes to energy production by transporting long-chain fatty acids into the mitochondria to be oxidized and turned into energy.

Unfortunately, not all people are able to produce enough carnitine. There are individuals who have to take carnitine supplements to augment their supply of this nutrient. Preterm infants, as well as individuals suffering from a genetic or medical disorder, are often carnitine deficient. Carnitine deficiency does not discriminate; it can affect men, women, and children of all ethnicities and ages.

Carnitine is an essential nutrient for certain cells, such as the muscle cells. Since these cells depend on fatty acids to thrive, the muscle tissues become weaker when they are not getting enough carnitine. Now imagine the muscle cells in the heart getting weaker from lack of carnitine. People who are carnitine deficient are likely to suffer from liver disease, muscle weakness, and heart problems.

The good news is, some foods are naturally high in carnitine. These foods include meat, fish, poultry, and milk. Red meat, in particular, has the highest carnitine content. The redder the meat, the more carnitine it contains. Dairy products, such as milk, cheese, ice cream, contain modest amounts of carnitine too.

Carnitine supplementation is also a great solution for people who are carnitine deficient. As long as you are getting the supplements from a trusted source and the products are derived from excellent sources, you can avoid the symptoms and potential health risks of carnitine deficiency.

Types of Carnitine Deficiency

There are two types of carnitine deficiency, primary and secondary carnitine deficiency:

Primary Carnitine Deficiency

Also known as systemic carnitine deficiency or carnitine uptake defect, primary carnitine deficiency is a metabolic disorder that is characterized by the body’s inability to use certain fats for energy, which affects the liver and the heart.  This leads to a defect in the proteins that transports carnitine. About 1 in 100,000 newborns are suffering from primary carnitine deficiency.

People afflicted with this condition have weak hearts, enlarged heart muscles, and an enlarged liver. Since the muscle cells in the heart are not getting the nutrients they need, the heart itself is unable to pump blood efficiently. The added strain causes the heart muscles to expand, leading to abnormal enlargement of the heart muscles. The same thing happens to the cells in the liver, if they are not getting enough nutrients, the liver has to work harder to break the fats down from the food you eat. The extra strain causes the liver tissues to expand, potentially causing liver disease. Primary carnitine deficiency could also cause skeletal muscles weakness.

Primary carnitine deficiency causes the blood sugar level to drop to dangerous levels. When this happens, the brain is unable to receive the nutrients it needs to develop fully. This leads to irreversible learning problems or even intellectual disability. Without early detection, primary carnitine deficiency can be fatal. It can also lead to permanent brain damage.

Secondary Carnitine Deficiency

This condition is more common than primary carnitine deficiency and is often caused by the body’s inability to produce carnitine in the blood. Secondary carnitine deficiency could affect the body's ability to absorb the nutrients from the food you eat, leading to nutrient deficiencies. This condition usually affects the liver, kidneys, and digestive system. Secondary carnitine deficiency may lead to liver disease, malnutrition, kidney disorders, and mitochondrial disease.

Causes of Carnitine Deficiency 

An abnormal gene, metabolic disorders, hereditary disorders, enzymes deficiencies and certain medical conditions often cause carnitine deficiency. When left untreated, carnitine deficiency could lead to:

  • Liver disease
  • Kidney disease (especially with dialysis)
  • Gastrointestinal disease
  • Malnutrition
  • Mitochondrial disease
  • Certain metabolic disorders
  • Certain drugs, such as valproate

In some cases, carnitine deficiency may be triggered by severe diarrhea, when ketosis is present or the demand for fat oxidation is high. Primary carnitine deficiency is often passed down from parents to children while secondary carnitine deficiency may be caused by a severe medical problem. People who are suffering from severe kidney or liver disease have a higher risk of developing carnitine deficiency.

Symptoms of Carnitine Deficiency 

Primary and secondary carnitine deficiency has different symptoms and the former causes more severe symptoms than the latter. Unfortunately, since carnitine deficiency is common among children and infants, the symptoms will show during the first few years of life. However, there are cases wherein the symptoms manifested only after an individual has reached adulthood. Some of the most common symptoms of carnitine deficiency are:

  • Moderate to severe muscle weakness
  • Fatigue
  • Irritability
  • Weak muscle tone
  • Confusion
  • Lethargy
  • Nausea
  • Loss of appetite
  • Decrease in gastrointestinal motility
  • Liver enlargement
  • Heart enlargement
  • Abdominal cramps
  • Delayed motor movement
  • Malnutrition in infants and children
  • Hypoglycemia for patients afflicted with liver disease
  • Edema or abnormal bloating
  • Shortness of breath for patients afflicted with heart disease

Do note that the symptoms and their severity will vary from patient to patient. In some cases, there is no symptom/s at all. Other times, the symptoms will manifest when a patient skips a meal, engages in rigorous activities or after suffering an illness. If you suspect that you are carnitine deficient, see a doctor for a diagnosis and do not self-medicate. In addition, avoid any known triggers to prevent the onset of the symptoms.

Apart from the symptoms we’ve listed above, carnitine deficiency could also lead to the following conditions:

Angina: This is a type of chest pain caused by reduced blood flow to the heart. Some studies associate carnitine deficiency with angina.

Rapid Weight Loss: Since carnitine deficiency leads to the decreased conversion of fat to fuel, the condition could cause rapid weight loss and decreased muscle mass.

Memory Impairment: One of the most serious after-effects of carnitine deficiency is temporary and permanent memory loss. Some studies suggest that carnitine deficiency could increase the risk of various memory impairment and related diseases like Alzheimer's disease among seniors.

Male Infertility: Multiple studies suggest that carnitine deficiency could lead to lower sperm count in men. L-carnitine supplementation may decrease the risk of male infertility.

Hyperthyroidism: Low carnitine may trigger or aggravate hyperthyroidism symptoms. These symptoms include insomnia, palpitation, and tremors.

Diagnosing Carnitine Deficiency

How is a carnitine deficiency diagnosed? For a proper diagnosis, you have to be checked by a neurologist or geneticist. For infants and children, diagnosis is done through standard newborn screenings.

To diagnose the condition, your doctor will check your medical and family’s health history. You will go through a series of physical exams, which may include a neurological exam. Your doctor will also check your blood to measure the levels of carnitine and enzymes that may point to liver disease. Your creatine kinase will also be checked for muscle damage.

Other tests will include a urine test, exercise tests, genetic tests and heart tests. These tests are designed to confirm the presence of ketones in the body and identify the type of metabolic disorder you suffer from. A heart test is done to determine the extent of damage that the condition caused to the heart.

Make every doctor visit an opportunity to get to know your condition better. Start by writing down questions you may have about carnitine deficiency. We recommend bringing someone with you in case you are unable to ask the listed questions yourself as well as to remember your health provider’s medical advice.

Write down all the treatments, tests, and medications that you have to remember. Ask your doctor what tests or treatments he or she recommends and what the results could mean. Learn how the drugs and/or treatment help in controlling the condition. Research about a certain drug or treatment’s side effects so you know what to expect once the treatment starts. Ask your doctor if there are other treatments that could help control the disease other than the ones he or she recommended.

Treatments for Carnitine Deficiency

Supplementation is the best treatment for carnitine deficiency. Most supplements are sold in pill form. When shopping around for the best supplements for carnitine deficiency, choose those made from L-carnitine. This is the most viable form of carnitine. Taking L-carnitine supplements increases the amount of carnitine in the blood, allowing the body to use up the nutrient as quickly and efficiently as possible.

Because carnitine deficiency is a life-long condition, you have to take L-carnitine supplements for the rest of your life if you suffer from primary carnitine deficiency. On the other hand, if you suffer from secondary carnitine deficiency then you will take carnitine supplements from time to time only. Whatever type of carnitine deficiency you are afflicted with, you have to check your carnitine levels regularly even if you are taking carnitine supplements.

For patients who are suffering from liver, heart or kidney disease due to this condition, you will require additional treatments and stringent monitoring.

Apart from taking L-carnitine supplements, you can stabilize the carnitine levels in the body by:

Eating on Time

Never skip meals! Ideally, divide your three main meals into six small meals to stabilize the carnitine levels in the blood while also boosting the metabolic rate.

Stick to a Low Fat, High Carbs Diet

A low fat, high (complex) carbohydrates diet is the best diet for patients suffering from carnitine deficiency. Complex carbohydrates help fuel the organs while low-fat foods reduce the strain on the heart and liver.  Always watch your caloric intake and minimize your intake of saturated fats, trans-fats, sugar, and sodium for best results.

Take Multivitamins

Apart from boosting your diet with nutrient-dense whole foods, we recommend taking multivitamins. Choose a multivitamin that’s enriched with vitamin C, biotin, and riboflavin.

Take Your Meds on Time

This is a no-brainer. If your doctor recommends taking your medications at certain times, take the drugs on time. This will help prevent the onset of the symptoms.

Preventing Carnitine Deficiency

How to prevent carnitine deficiency? There is not much that you can do once you are diagnosed with this condition other than to take L-carnitine supplements. At this point, the only thing you can do is to protect your future kids from suffering from the same ailment. If your family has a history of carnitine deficiency, consult a specialist before starting a family.

If say, you carry the mutated gene that causes carnitine deficiency, you can use in vitro fertilization to test embryos for the condition. For early pregnancies, you can ask for amniocentesis to test for this disease.

Complications of Carnitine Deficiency

Heart Enlargement

Heart weakness is one of the most common (and severe) complications of carnitine deficiency. Since the heart is unable to pump blood efficiently due to muscle weakness, a patient may suffer from shortness of breath and decreased heart function. When left untreated, carnitine deficiency may lead to heart enlargement and early death.

Liver Disease

Liver disease is also a serious complication of carnitine deficiency. The lack of nutrients to the liver puts much strain on this organ. Eventually, the liver will enlarge and all its functions will be affected. Infants and children are at a higher risk of suffering from liver disease. Left untreated, liver problems may also lead to hypoglycemia, infections, coma, and in severe cases, early death. Do note that some patients respond well to L-carnitine supplementation but others don’t.


Carnitine deficiency may be a rare condition but it’s a serious one that requires a lifelong treatment. However, as long as you are taking the right medications and you are undergoing regular checkups, it is possible to minimize the risks of this condition.

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