MCAD Deficiency

What is MCAD Deficiency?

Medium-chain acyl-CoA dehydrogenase (MCAD) is an enzyme used to digest certain types of fat, and people with a MCAD don’t produce enough of it. This makes it hard to process medium-chain fats like coconut and palm oils.

Since dietary fat is essential for brain function as well as overall health, this genetic disorder must be diagnosed early in life to prevent serious complications. Children who go too long without treatment may end up permanently brain damaged, in need of a liver transplant, or in a coma.

What are the Symptoms of MCAD Deficiency?

A failure to thrive is the earliest sign a child is not digesting something properly or missing a crucial element of their diet.

Symptoms include

  • Lethargy and sluggish behavior
  • Vomiting after eating any meal with even the smallest amounts of medium-chain fats
  • Hypoglycemia, low blood sugar, and the resulting symptoms like nausea and lightheadedness between meals
  • Increase in symptoms when fasting or skipping meals

Since the disorder sets in during infancy, it’s easy to overlook the first symptoms. Paying close attention to your baby is essential so that serious nutritional issues like MCAD deficiency are detected before permanent damage is done. It’s easy to confuse the signs of this disorder with other childhood illnesses, so gene testing is necessary to rule out this problem.

How is MCAD Deficiency Treated?

Avoiding medium-chain fats is the first step in addressing this deficiency. Sticking to a tight schedule of meals also prevents hypoglycemia from setting in. High carbohydrate and protein-heavy diets are recommended, with careful amounts of safe fats mixed in with supervision.

A relatively safe supplement known as L-carnitine can also help, but only if recommended by the doctor overseeing the child’s treatment.

Last Reviewed:
October 10, 2016
Last Updated:
August 30, 2017