This nutrient is converted to vitamin A by the body, therefore, deficiency symptoms are the same as those of vitamin A. The earliest symptom is night blindness. Prolonged deficiency leads to more advanced changes in eye tissue. Other potential signs of mild to moderate deficiency include rough, dry skin, loss of appetite, loss of hair luster, brittle nails, joint pain, and possibly increased susceptibility to infection.

Deficiency may lead to depletion of fat-soluble vitamins (A, D, E, and K), eczema, and other skin disorders. In children, fat deficiency could cause growth retardation. Long-term deficiency could be associated with many chronic illnesses. Fats are stored in the body as fatty acids. There are three essential fatty acids that the body cannot make and, therefore, must get from dietary sources or supplements.

Depleted levels of iron may lead to anemia and weakened immune function. In the event of anemia, symptoms include dizziness, fatigue, shortness of breath, pale skin color, and possibly irregular heartbeat.

The earliest symptom of deficiency of this nutrient is night blindness. Prolonged deficiency leads to more advanced changes in eye tissue. Other potential signs of mild to moderate deficiency include rough, dry skin, loss of appetite, loss of hair luster, brittle nails, joint pain, and possibly increased susceptibility to infection.

Low levels of folic acid have been linked to anemia, heart disease, and birth defects.

Symptoms of vitamin B₁₂ deficiency are rare because it takes years to develop complications associated with long-term depletion of this nutrient. Irritability, weakness, numbness, anemia, loss of appetite, headache, personality changes, and confusion are some of the signs and symptoms associated with vitamin B₁₂ depletion. Low levels of this vitamin may also be associated with an increased risk of colon cancer, heart disease, brain disorders, and birth defects.

Vitamin D deficiency leads to abnormal bone formation (rickets) in children and softening of the bones (osteomalacia) in adults. Vitamin D deficiency interferes with calcium absorption, leading to deficiency of that nutrient with all of the associated symptoms (such as increased risk of fractures, osteoporosis (bone loss), and muscle weakness). Because this nutrient is fat-soluble, prolonged periods of deficiency are required to produce these symptoms.

While deficiency of this nutrient is uncommon, it negatively affects muscle tissue, red blood cells, nervous, and reproductive systems. Over the long-term, depleted levels of this nutrient may also be associated with cancer, heart disease, and altered immune function.

The major symptom of vitamin K deficiency is an inability of the blood to clot properly, which may lead to excessive bleeding and a tendency to bruise easily.

The selected depletions information presented here identifies some of the nutrients that may be depleted by certain medications. The signs and symptoms associated with nutrient deficiency may also indicate conditions other than nutrient deficiency. If you are experiencing any of the signs or symptoms mentioned, it does not necessarily mean that you are nutrient deficient. Nutrient depletion depends upon a number of factors, including your medical history, diet, and lifestyle as well as the length of time you have been taking the medication. Please consult your healthcare provider; he or she can best assess and address your individual healthcare needs, and determine if you are at risk for nutrient depletions from these medications as well as others not listed here.

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