Metabolic disorders: here's what you need to know

Medically reviewed on August 1, 2022 by Jillian Foglesong Stabile, MD, FAAFP. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

• What is a metabolic disorder?
• 7 examples of metabolic disorders
• Test for metabolic disorders at home

Your body is like a well-oiled machine. Under the surface, there are thousands of processes taking place, keeping you in tip-top shape. One of the most crucial pieces of the puzzle is your metabolism.

So, what is metabolism? Your metabolism plays a role in numerous bodily functions, from keeping your blood circulating to digesting your food. However, not everyone has a metabolism that always functions at full capacity.

For some people, regular metabolic function is impacted by a metabolic disorder—an issue that arises when abnormal chemical reactions disrupt the metabolic process. To help you understand these relatively rare disorders, we’ll be examining metabolic disorders in more depth, including the causes, signs, and treatment options for several conditions.

What is a metabolic disorder?

A metabolic disorder is any condition that disrupts the normal function of your metabolism.

When functioning properly, your metabolism turns the calories you consume into energy by combining them with oxygen and dispersing them throughout your body. Using various hormones and enzymes, your metabolism breaks down the foods you eat, turning nutrients into fuel or storing it for later.

Through proper nutrition, metabolic processes can also help your body maintain body temperature, grow, and heal wounds.

Typically, metabolic disorders occur when you have too much or too little of the chemical substances involved in healthy metabolic function. These disorders impact your metabolism by interfering with one or more of the following “ingredients” of the metabolic process:

• Amino acids
• Carbohydrates
• Lipids
• Proteins

Other metabolic disorders, known as mitochondrial diseases, affect the parts of your cells that produce energy.

Where do metabolic disorders come from?

The metabolic process is complex, and there are various steps along the way where something can go wrong. As such, metabolic disorders occur in a few different ways, including [2]:

• Genetics – Many metabolic disorders pass from parents to their children at birth. These inherited metabolic diseases or disorders (also called inborn errors of metabolism) can come from one or both parents.
• Hormone deficiencies – Hormones like testosterone, cortison, leptin, and insulin play a role in normal metabolic function. If there’s an imbalance or a deficiency in one or more of these hormones—especially for a prolonged period—problems can arise.
• Organ issues or failures – When organs associated with the metabolic process—such as the liver, pancreas, or kidneys—stop functioning as they should, metabolic disorders can occur. Some issues with internal organs are genetic, while others can crop up long after birth.

Regardless of where they come from, metabolic disorders can affect quality of life. Catching them as early as possible is ideal—and the best way to do that is to learn the signs and symptoms of common disorders.

7 examples of metabolic disorders

There are hundreds of metabolic disorders in existence, ranging from somewhat common to exceedingly rare. [4] Here are seven examples of metabolic disorders you should know about, along with their causes, symptoms, and treatment options.

Diabetes

Diabetes is one of the most prevalent metabolic disorders, affecting around 1 in 10 Americans. [5] Although diabetes is classified as an autoimmune disease, it is in fact a metabolic disorder, as insulin—the hormone affected by diabetes—is involved in the metabolic process.

There are two varieties of diabetes:

• Type 1 diabetes – Type 1 diabetes is an inherited condition that keeps your pancreas from producing insulin.
• Type 2 diabetes – The much more common type 2 diabetes can be inherited or acquired later in life due to excess weight or lack of physical activity. With type 2, your body produces insulin, but doesn’t use it well.

Symptoms of diabetes include: [6]

• Frequent urination
• Frequent feelings of hunger and thirst
• Blurry vision
• Dry skin
• Sores and infections that take longer to heal

Luckily, both types of diabetes are treatable. For type 1 diabetes, treatment involves insulin injections or an insulin pump. For type 2, recommended lifestyle changes include healthy eating, an exercise regimen, and, sometimes, taking medications.

Gaucher disease

Gaucher disease (pronounced go-SHEY) is a rare disorder that shows up in roughly one of every 40,000 births. [7] It is a lysosomal storage disorder that causes fatty substances to build up in the spleen, liver, and other organs. When overloaded with fats, these enlarged organs may cause pain and struggle to function.

As a hereditary disorder, Gaucher disease is only passed to children if both parents carry the gene that causes it.

Symptoms of Gaucher disease include: [8]

• Anemia (low red blood cell count)
• Abdominal pain
• Bone pain or weak bones
• Fatigue
• Frequent bruising
• Frequent nosebleeds

Most types of Gaucher disease are treatable. Typical treatment involves enzyme replacement therapy (ERT) and substrate reduction therapy (SRT). [7] ERT is performed via IV, while SRT is administered orally.

Hunter syndrome

Hunter syndrome is a very rare genetic metabolic disorder that is much more prevalent in males. [9] The metabolic syndrome occurs when an important enzyme is either missing or not functioning properly.

Symptoms of Hunter syndrome tend to show up between the ages of 2 to 4 and include [10]:

• Macrocephaly (enlarged head)
• Broad nose
• Thick lips
• Enlarged vocal cords that lead to a deeper voice
• Chronic diarrhea
• Stiff joints
• Developmental delays

These symptoms can lead to respiratory and cardiac complications. While there is no cure for Hunter syndrome, there are ways to manage the complications that arise. For example, sleep apnea is a common symptom, so devices that keep the airway open during sleep are often prescribed.

Maple syrup urine disease (MSUD)

Another inherited disorder, maple syrup urine disease (so-called because of the sweet odor of urine produced by affected individuals) is caused by inefficiencies in processing amino acids. MSUD affects approximately 1 in 185,000 infants around the world. [11]

Other symptoms of the disease include:

• Vomiting
• Lethargy
• Atypical movements
• Delayed development
• Seizures (if untreated)

Because people with MSUD struggle to break down the amino acids valine, leucine, and isoleucine, the most common treatment is a lifelong diet plan that limits the consumption of these amino acids. [12] When left untreated, MSUD can result in a coma or, in rare cases, death.

Phenylketonuria (PKU)

PKU is an inherited metabolic disorder that leads to a build-up of phenylalanine (an amino acid).

Although PKU is rare, it can cause severe problems. [13] Typical symptoms include:

• Odorous skin, breath, or urine
• Frequent rashes or eczema
• Hyperactivity
• Microcephaly (reduced head size)
• Delayed development
• Behavioral issues

As with MSUD, treatment revolves around limiting foods containing the problematic amino acid, such as aspartame- and protein-rich options.

Tay-Sachs disease

Like MSUD, Tay-Sachs disease is a genetic metabolic disorder caused by an inability to break down a substance involved in metabolizing. However, in the case of Tay-Sachs, patients that are affected are missing an enzyme that helps process fatty substances. [14]

The most common form of Tay-Sachs disease is infantile; signs of the disease begin to show at three to six months. [14] Typical symptoms include:

• Problems with movement
• Seizures
• “Cherry-red” spots in the eyes
• Trouble swallowing
• Loss of hearing and vision
• Muscle weakness and issues with motor skills

In rare cases, juvenile or late-onset Tay-Sachs disease can occur in children aged five and up. [15] Symptoms differ from the infantile form and include:

• Respiratory infections
• Behavioral problems
• Decline in mental function
• Weakened muscles
• Tremors or muscle spasms
• Psychiatric disorders

Unfortunately, Tay-Sachs disease is often fatal, as it can progressively worsen. However, genetic screening tests can identify the genes associated with the disease. If you have a family history of the disease, you can undergo genetic screening and counseling before conceiving.

Wilson’s disease

Wilson’s disease is an inherited metabolic disorder that leads to a build-up of copper in the brain, liver, and other organs. [16] As a genetic disorder, it’s passed from parent to child at birth.

Although most people don’t think of copper as something to consume, the body requires a certain amount of the mineral to develop nerves, bones, melanin, and collagen. Under normal circumstances, your body absorbs the necessary amount of copper from your diet, then sends the leftovers to your liver for disposal.

However, if you suffer from Wilson’s disease, your body will continue to absorb copper—and it’s possible to have too much of a good thing.

There are a few telltale signs of Wilson’s disease, such as [16]:

• A golden-brown discoloration of the eye
• Jaundice
• Fluid building in the abdomen and/or legs
• Fatigue
• Loss of appetite
• Muscle stiffness

While excessive copper can be life-threatening, Wilson’s disease is treatable—especially when caught early. Treatment involves taking medications throughout one’s life and continuing to monitor symptoms. [17]

Test metabolism hormones at home

One way to check your metabolic health is to take an at-home Metabolism Test from Everlywell. Our test measures three hormones—cortisol, free testosterone, and thyroid-stimulating hormone (TSH)—that are vital to a healthy metabolism.

While a single test won’t be able to confirm whether or not you have a metabolic disorder, it can help you determine what your next steps should be.

Remember: Only a healthcare provider can give you an official diagnosis. Until then, you shouldn’t take a hormone imbalance as proof that you have a metabolic disorder—but it may mean you should follow up with additional testing.

Related content

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References

1. Metabolism. Cleveland Clinic. URL. Accessed August 1, 2022.
2. Metabolic Disorders. MedlinePlus. URL. Accessed August 1, 2022.
3. Nutrition, Anabolism, and the Wound Healing Process: An Overview. ePlasty. URL. Accessed August 1, 2022.
4. Inherited metabolic disorders. Mayo Clinic. URL. Accessed August 1, 2022.
5. Statistics About Diabetes. American Diabetes Association. URL. Accessed August 1, 2022.
6. Diabetes Symptoms. Centers for Disease Control and Prevention. URL. Accessed August 1, 2022.
7. What is Gaucher Disease? National Gaucher Foundation. URL. Accessed August 1, 2022.
8. Gaucher disease. Mayo Clinic. URL. Accessed August 1, 2022.
9. Mucopolysaccharidosis type II. MedlinePlus. URL. Accessed August 1, 2022.
10. Hunter syndrome. Mayo Clinic. URL. Accessed August 1, 2022.
11. Maple syrup urine disease. MedlinePlus. URL. Accessed August 1, 2022.
12. Maple Syrup Urine Disease. Cleveland Clinic. URL. Accessed August 1, 2022.
13. Phenylketonuria (PKU). Mayo Clinic. URL. Accessed August 1, 2022.
14. Tay-Sachs disease. Mayo Clinic. URL. Accessed August 1, 2022.
15. Tay-Sachs disease. MedlinePlus. URL. Accessed August 1, 2022.
16. Wilson’s disease. Mayo Clinic. URL. Accessed August 1, 2022.
17. Wilson Disease. National Organization for Rare Diseases. URL. Accessed August 1, 2022.
18. Tay-Sachs disease. Mayo Clinic. URL. Accessed August 1, 2022.