Moderate lactose intolerance might also be a symptom of Western diets rich in processed food. I also had it for most part of 15 years. Then I discovered that I could drink whole milk in small quantities if combined with cereal or cacao. During this time I continued to consume yoghurts and other dairy products. For a time I even made my own yoghurt or kefir because I could not consume whole milk so it was only logical to ferment it.