Dopamine is replaced naturally by the brain, which produces dopamine from precursor amino acids typically obtained through eating, according to Dr. Emily Deans for Psychology Today. The precursor essential amino acid phenylalanine produces the amino acid tyrosine, which crosses the blood-brain barrier and is converted to dopa, becoming dopamine.
The precursor amino acids can also be obtained through taking L-tyrosine supplements, generally in pill or tablet form, as suggested by The Dr. Oz Show, or through the medication levodopa, known by the brand names Parcopa and Sinemet, according to WebMD.
Eating foods that contain high levels of tyrosine can boost the production of dopamine. Food sources with large amounts of tyrosine include almonds, avocados, bananas, dairy products, lima beans, pumpkin and sesame seeds, according to the Franklin Institute. Foods that are high in phenylalanine include beef, poultry, pork, fish, milk, yogurt, eggs, cheese, soy products, certain nuts and seeds and aspartame, an artificial sweetener, explains the University of Maryland Medical Center.
To convert tyrosine or phenylalanine into dopamine, the brain needs adequate supplies of oxygen, folic acid, iron, copper and vitamins B3, B6 and C, notes the Franklin Institute. Because dopamine oxidizes very easily, consumption of antioxidants in fruits and vegetables and supplements of vitamins C and E is recommended to protect the neurons that use dopamine from free radical damage.