Neurotransmitters are the chemicals the brain uses to regulate our energy, mood, emotional stability and more. Some are designed to give us energy (excitatory) while others help us feel calm and relaxed (inhibitory). Ideally, we have sufficient reserves working in harmony, but often neurotransmitters are depleted by various stressors, including the pressures of modern life. Neurotransmitter imbalances can result in depression, insomnia, anxiety, poor concentration, fatigue, weight gain, hyperactivity and restlessness to name a few.