A vitamin deficiency occurs when a child does not get enough of a specific nutrient to ensure proper body functioning. Although not all vitamin or mineral deficiencies are dangerous, certain deficiencies can cause serious illnesses and health conditions. One symptom of vitamin deficiencies might include excessive licking, typically of non-food items. If your child frequently licks objects or people, consult your physician -- while it may be caused by a vitamin deficiency, it could also be caused by other serious conditions.
Specific symptoms depend on which vitamin is deficient in the child's body. However, common signs and symptoms of deficiencies include fatigue, lack of energy, weakened immune system, dry skin, dental problems, difficulty concentrating, weight loss or insufficient weight gain, muscle weakness and brittle bones. More specific symptoms include unpleasant body odors from vitamin B12 deficiency, easy bruising from vitamin C deficiency and insomnia from vitamin D deficiency.
Although licking might not be directly caused by a vitamin deficiency, it could be a related side effect. For example, vitamin A deficiency can cause a decreased sense of smell. Children with this deficiency might develop a licking habit to compensate for the loss of smell. Additionally, children with a folic acid deficiency often experience a sore tongue. In this case, children might attempt to relieve the soreness by licking cold or smooth objects.
Other Possible Causes
If your child exhibits excessive licking characteristics, consult your physician to help determine the exact cause of the symptom. While some licking disorders are related to nutritional deficiencies, others can relate to mental or nervous disorders. Sensory processing disorder is a condition that occurs when the body's sensory signals become disorganized and are unable to trigger appropriate motor and behavioral responses. While some children with SPD avoid the stimulation of certain senses, other children seek enhanced sensory stimulation, which could include excessive licking to stimulate the sense of taste. If your child has sensory-seeking SPD, additional symptoms might include fidgeting, hugging tightly, frequently rubbing against walls or furniture, engaging in vigorous physical play and an obsession with different textures.
Pica is a serious eating disorder characterized by compulsive cravings for non-food items. Although pica can be caused by a variety of conditions, including developmental disorders and mental health conditions, nutritional deficiencies are a common cause of the disorder. Specifically, children with an iron or zinc deficiency are at risk for developing pica. Children with pica might crave non-food items like dirt, clay, chalk, baking soda, ice, glue, hair, paper, sand and soap, among other items. Typically, the disorder extends beyond licking, and children with the condition actually consume these items. If your child displays symptoms of pica over several weeks, consult a health-care professional. Consuming non-food items could result in dangerous side effects, including lead poisoning, toxicity, dental problems and intestinal obstructions.