The average Indian height is going down with every generation due to the eating habits and also due to malnutrition. To play football, you need to be strong and tall. That is the main reason European, African and American teams are doing better. After the 2nd world war countries like South Korea, Japan and China started better calorific diet in schools for breakfast and lunch with meat amongst others basically replacing rice based food. Most of us know that the average calorific value of diet of 50 indians is equal to 1 american, just for an example. So mid day school meals, breakfast for everyone till 12th grade and making it compulsory is a must for the Indias. Afterall, one in six in the world is an Indian.
