Why junk food makes you want more
Accumbal serotonin hypofunction and dopamine hyperfunction due to chronic stress and palatable food intake in rats
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Rats that ate lots of chocolatey food had more dopamine (a 'feel-good' chemical) in their brain, and when they stopped eating it and got plain food instead, their serotonin (another mood chemical) dropped. Stress made this even more confusing.
Surprising Findings
Re-feeding stressed rats with palatable food increased serotonin, but re-feeding rats with prior palatable food intake decreased serotonin.
Common belief is that palatable food always boosts mood via serotonin—but here, it only helps if you haven’t been eating it. For those used to it, normal food makes serotonin drop.
Practical Takeaways
If you're trying to cut junk food, expect a temporary mood dip—it may be your brain adjusting to lower serotonin after chronic high-sugar intake.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Rats that ate lots of chocolatey food had more dopamine (a 'feel-good' chemical) in their brain, and when they stopped eating it and got plain food instead, their serotonin (another mood chemical) dropped. Stress made this even more confusing.
Surprising Findings
Re-feeding stressed rats with palatable food increased serotonin, but re-feeding rats with prior palatable food intake decreased serotonin.
Common belief is that palatable food always boosts mood via serotonin—but here, it only helps if you haven’t been eating it. For those used to it, normal food makes serotonin drop.
Practical Takeaways
If you're trying to cut junk food, expect a temporary mood dip—it may be your brain adjusting to lower serotonin after chronic high-sugar intake.
Publication
Journal
Nutritional Neuroscience
Year
2024
Authors
C. García-Luna, E. Espitia-Bautista, E. Alvarez-Salas, P. Soberanes-Chávez, P. de Gortari
Related Content
Claims (6)
Auditory feedback during mastication modulates perceived food satiety and influences subsequent food intake via dopaminergic reward pathways.
When rats are stressed and eat sugary food, their brain’s chemical balance changes differently when they’re hungry versus when they eat again—especially in the area linked to pleasure and reward.
Whether a rat is hungry or just ate, and what it’s been eating before, changes the levels of two key brain chemicals in its reward center.
When rats eat lots of sugary, fatty food for a long time, their brain's pleasure center becomes more active with dopamine, which might make them keep eating even when they don't need to.
When stressed rats eat sugary food after being hungry, their brain's serotonin activity goes up—but if they’ve been eating sugary food for a while and then eat normal food, serotonin activity drops.