Palatable foods release brain opioids and dopamine in the
limbic system (1–3). For example, a tasty food can activate
opioid receptors in the ventral tegmental area (VTA) and
thereby stimulate cells that release dopamine in the nucleus
accumbens (NAc) (4). Conversely, opiates or dopamine
injected into the NAc can stimulate animals to eat palatable
food (5–7).