Big Health Benefits To Small Weight Loss (nytimes.com)
schwit1 writes: Obese individuals who lose as little as 5 percent of their body weight can improve their metabolic function and reduce the risk of developing Type 2 diabetes and heart disease, a new study has found. Many current treatment guidelines urge patients to lose between 5% and 10% of their body weight in order to experience health benefits, but the recommendations were based on earlier studies that didn't distinguish between participants who lost only 5 percent of their weight and those who lost more.
Based on your anecdote it's hard to see how the main factor in your improved health wasn't the removal of the stressors in your life.