You're talking about the difference in how you feel in the short term, in an uncontrolled "experiment", where you started exercising at the same time, versus an increase in long term disease. Of course you're going to feel better if you lose 30 pounds and start exercising. What's to say you wouldn't feel even better than that if you dropped all of those carbs and started eating far more vegetables and other vitamin rich non-proteins instead of all that yogurt? No offense, but do a line of cocaine and you'll feel better for a short period of time, too. It doesn't mean you're healthier or increasing your life expectancy.