Dopamine is a neurotransmitter that derives from an amino acid known as tyrosine. It is essential to numerous bodily systems including the renal, cardiovascular, endocrine and central nervous systems. A deficit in proper dopamine levels may cause a complication in both motor function and emotional state. Therefore, symptoms such as drastic mood swings, decreased libido, inattention and sleep disturbances are often attributed to low dopamine levels. Illnesses such as Parkinson's disease and Attention Deficit/Hyperactivity Disorder (ADHD) are also linked to low dopamine levels.
Low dopamine levels in men cause symptoms similar to those associated with decreasing levels of the hormone testosterone. Changes generally occur on both a physical and a sexual level. For example, low dopamine levels will usually decrease a man's bone density, sex drive, physical endurance and muscle mass. Also, low dopamine levels will usually increase a man's cholesterol levels and body fat.
Low dopamine levels in women cause symptoms similar to those associated with decreasing levels of the hormone oestrogen. For example, low dopamine will generally increase the adverse effects that often arise during menopause. These include hot flashes, night sweats, sleep disturbances and mood swings.
Dopamine acts as an excitatory hormone, which means it plays a major role in the sensations of pleasure, excitement and reward. This is why low levels of dopamine will often decrease an individual's libido. Decreased dopamine levels will also hinder other activities associated with pleasure or excitement including motor functions, cravings, compulsion and satisfaction. Contrarily, a spike in dopamine levels will generally leave an individual anxious or hyperactive.
Perhaps the most acute symptom of low dopamine is an increased risk of Parkinson's disease. This illness is characterised by several symptoms including trouble walking, rigid movement, impaired balance, difficulty swallowing or chewing, and muscle aches. Parkinson's is typically preceded by shakes or tremors in one side of the body (particularly the hands). While not fatal, Parkinson's has no cure and gradually worsens over time.
It is suggested that low levels of dopamine may be linked to ADHD. This is why the drug Ritalin, which boosts dopamine levels in the brain, is often prescribed for children with ADHD. Individuals with ADHD typically suffer from bouts of hyperactivity, impulsivity or inattention, which commonly leads to difficulty in academic, emotional or social functioning. ADHD is more common among children than adults, with most cases occuring before the age of seven.