For example, a recent randomized controlled trial reported that CBT reduces levels of CRP in insomnia,83 a condition which is frequently associated with depression.84, 85 In contrast, two pre-post studies found no reduction in CRP levels during CBT in patients with depression, although one of these studies reported decreased expression of Toll-like receptors after CBT.86, 87 CBT mainly consists of two core components: behavioral activation and cognitive therapy.88 When applying behavioral activation, individuals may increase both physical activity and pleasurable experiences. This evidence concerns the gene CRP and major depressive disorder.