Your max height potential is genetic and has to do with adaptation to an environment or sexual selection. Nothing to do with the way sikhs ate in past as that won't affect the DNA. Food is a factor, but more so for poor people who barely eat and won't be able to reach their genetic potential. People of average wealth that eat decent do reach that potential. Again, south brahmins aren't genetically brahmins at all and claim it for privilege. When you bring up the point "us brahmins are not known for being tall", I found that hilarious.

Why bring up the average in a country known for poverty? As explained above, poor people don't get to their full genetic potential due to lack of food and hence mess up the statistics. The average for UPPER CLASS castes who actually eat are most likely 5'9 at least. You're short bud even for a well fed indian.