Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) VLCAD deficiency ?
    ### Response:
    VLCAD deficiency is a condition in which the body is unable to properly breakdown certain fats (called very long-chain fatty acids) into energy, particularly during periods without food (fasting). Signs and symptoms can occur during infancy, childhood or adulthood depending on the form of the condition and may include low blood sugar (hypoglycemia), lack of energy, and muscle weakness.
    