Nutrition & Metabolism Disorders
A metabolic disorder occurs when the metabolism process fails and causes the body to have either too much or too little of the essential substa...
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Nutrition & Metabolism Disorder Overview
Metabolism is the chemical process your body uses to
transform the food you eat into the fuel that keeps you alive. Nutrition (food)
consists of proteins, carbohydrates, and fats. These substances are broken down
by enzymes in your digestive system, and then carried to the cells where they
can be used as fuel. Your body either uses these substances immediately, or
stores them in the liver, body fat, and muscle tissues for later use.
What Is a Metabolic Disorder?
A metabolic disorder occurs when the metabolism process
fails and causes the body to have either too much or too little of the
essential substances needed to stay healthy.
Our bodies are very sensitive to errors in metabolism. The body
must have amino acids and many types of proteins to perform all of its
functions. For example, the brain needs calcium, potassium and sodium to
generate electrical impulses, and lipids (fats and oils) to maintain a healthy
Metabolic disorders can take many forms. For instance:
- a missing enzyme or vitamin that is necessary
for an important chemical reaction
- abnormal chemical reactions that hinder
- disease in the liver, pancreas, endocrine glands
or other organs involved in metabolism
- nutritional deficiencies
What Causes Metabolic Disorders?
You can develop a metabolic disorder if certain organs (for
instance, the pancreas or the liver) stop functioning properly. These kinds of
disorders can be a result of genetics, a deficiency in a certain hormone or
enzyme, consuming too much of certain foods, or a number of other factors.
There are hundreds of genetic metabolic disorders caused by mutations
of single genes. These mutations can be passed down through generations of
families. According to the National Institutes of Health (NIH), certain racial
or ethnic groups are more likely to pass on defective genes for particular
inborn disorders (NIH).
The most common of these are:
- sickle cell anemia in African Americans
- cystic fibrosis in people of European heritage
- maple syrup urine disease in Mennonite
- Gaucher’s disease in Jewish people from Eastern
- hemochromatosis in Caucasians in the U.S.
Types of Metabolic Disorders
Diabetes is the most common metabolic disease. There are two
types of diabetes: type 1, the cause of which is unknown—although there can be
a genetic factor—and type 2, which can be acquired, or potentially caused by
genetic factors as well. According to 2011 data from the American Diabetes
Association, 25.8 million children and adults, or about 8 percent of the U.S.
population have diabetes (ADA, 2011).
In type 1 diabetes, the T cells attack and kill beta cells
in the pancreas, the cells that produce insulin. Over time, a lack of insulin
can cause nerve and kidney damage, eyesight impairment, and increased risk of
heart and vascular disease.
Hundreds of inborn errors in metabolism (IEM) have been
identified, and most are extremely rare. However, it is estimated that IEM collectively
affects 1 in every 1,000 infants. Many of these disorders can only be treated
by limiting dietary intake of the substance or substances the body cannot
The more common types of nutritional and metabolic disorders
disease: This condition causes an inability to break down a particular kind
of fat, which accumulates in the liver, spleen and bone marrow. This inability can
result in pain, bone damage and even death. It is treated with enzyme
galactose malabsorption: This is a defect in the transport of glucose and
galactose across the stomach lining which leads to severe diarrhea and
dehydration. Symptoms are controlled by removing lactose, sucrose and glucose
from the diet.
hemochromatosis: In this condition,
excess iron is deposited in several organs, and can cause liver cirrhosis, liver
cancer, diabetes, and heart disease. It is treated by removing blood from the
body (phlebotomy) on a regular basis.
syrup urine disease: This condition
disrupts the metabolism of certain amino acids, causing rapid degeneration of
the neurons. If not treated, it causes death within the first few months after
birth. Treatment involves limiting the dietary intake of branched-chain amino
(PKU): PKU causes an inability to
produce the enzyme, phenylalanine hydroxylase, resulting in organ damage,
mental retardation and unusual posture. It is treated by limiting the dietary intake
of certain forms of protein.
Metabolic disorders are highly complex and rare. Even so,
they are the subject of ongoing research, which is also helping scientists to
better understand the underlying causes of more common problems such as
lactose, sucrose, and glucose intolerance, and the overabundance of certain
Sandy Calhoun Rice
Medically Reviewed by:
George Krucik, MD, MBA
May 10, 2013
Published By: Healthline Networks, Inc.