I’ve seen the claims online and you probably have too. Internet influencers promise natural and quick-fix ways to boost serotonin levels, so your moods are balanced and you're always uber-happy.

If you’ve heard of two of the brain’s chemical neurotransmitters, it’s probably dopamine and serotonin. Never mind that glutamate and GABA do most of the work — it’s the thrill of dopamine as the ...