Why do we get addicted to things?

The brain’s reward circuit, centred on the neurotransmitter dopamine, evolved to reinforce behaviours essential for survival, like eating and social bonding. Addictive substances such as nicotine, alcohol and opioids cause unnaturally large dopamine surges. With repeated exposure, the brain reduces its own dopamine receptors (tolerance), so normal activities feel less rewarding and more of the substance is needed. Cravings become intense, and withdrawal is unpleasant. Genetic factors account for about 40 to 60 percent of addiction risk. Behavioural addictions, like gambling, engage similar dopamine pathways. Modern treatment combines medication, therapy and support groups to help rewire the reward system.