So, how could he increase it?
Hendra kept a tight sleep schedule. And, due to his prohibition to consume sleeping pills, he forced his body to spend its energy with strenuous workout, until he was dripping in sweat every time he would take a nap or sleep for the night.
Besides that, he also consumed a healthy diet of avocado and dark chocolate to heightened the level of happiness hormones in his body. Both things consisted of rich antioxidants that would increase N-Acylethanolamine to stimulate his brain into releasing endorphins and make him feel better, naturally.
He also ate nuts and seeds, salmon that contained tryptophan, omega 3 fatty acids, EPA, DHA, also vitamin B6 and B12, that would make him feel better, reduce inflammation, and protect the nerves in his brain.
But, the most important thing in his diet was drinking two liters of water every day.