Hindus do not eat non vegetarian food like chicken, meat or fish or any other Non Vegs on particular days, not limited but including: Mondays, Thursdays, and Saturdays of every week, many more auspicious days like Yekadashi, Sankranti, Dussera, Sankashti Chaturthi, Angarki Chaturthi, Ekadashi, Gudhipadwa, Akshaytrutiya, Diwali (all the days).
Amongst these, the reason for not eating meat on some particular days excluding weekly days is purely religious. Killing of animals is considered as a sin in Hinduism. So, people avoid eating meat at least on those auspicious days to maintain sacredness of that particular day.
The reason behind not eating meat on weekdays including Mondays, Thursdays, and Saturdays is that as a human being we need only a little amount of meat to fulfill requirements of our body such as iron, vitamin B12 and other vital nutrients. But human being basically is also like an animal and we can get addicted to eating meat. As we all know eating excessive meat is not good for health.
It can cause diseases like piles, kidney stones, colon cancer, blood pressure, heart attack, etc.
Then also people cannot refrain themselves from eating flesh. Therefore, Hinduism has placed some restrictions by assigning the days to particular diet. Some are
- Monday is dedicated to Lord Shiva,
- Tuesday to Lord Hanuman,
- Thursday to Lord Dattatreya and Lord SaiBaba, and
- Saturday to Lord Hanuman, Lord Venkateswara.
And yes, in some parts of india, Even wednesday and friday are also dedicated to some lords but i’m sure they left some day alone not dedicating to any god. In this way, people have been assigned some religious restrictions and as most Hindus are religious, they do obey this rule. Following this, they restrict Non vegetarian in their diet which is good for their health.