(Guardian): Treating earache: 
2000BC: Here, eat this root. 
1000AD: That root is heathen. Here, say this prayer.
1850AD: Prayer is superstition. Here, drink this potion.
1940AD: That potion is snake oil. Here, swallow this pill.
1985AD: That pill is ineffective. Here, take this antibiotic.
2000AD: That antibiotic is artificial. Here, eat this root. —Alternative Medicine is Practically Mainstream