A fruitarian diet , which consists solely of fruit, is deficient in protein, salt, and many micronutrients and is not recommended. A physician should be alert to early evidence of nutrient deficiency or toxicity in patients adhering to them. Such diets have resulted in frank vitamin, mineral, and protein deficiency states and cardiac, renal, and metabolic disorders as well as some deaths. Some trace mineral supplements have induced toxicity. Patients with alcohol or drug problems are notoriously unreliable when questioned about their eating habits, so making judicious inquiries of relatives or acquaintances may be necessary.
Addiction leads to a disturbance of lifestyle in which adequate nourishment is neglected.
Absorption and metabolism of nutrients are also impaired. High levels of alcohol are poisonous and can cause tissue injury, particularly of the GI tract, liver, pancreas, brain, and peripheral nervous system. Drug addicts are usually emaciated. A history of poor appetite, GI disturbance, and recent sizable weight loss suggests the possibility of malnutrition. A history of bleeding may indicate iron deficiency.