Kural - 255

If flesh you eat not, life's abodes unharmed remain;
Who eats, hell swallows him, and renders not again

Explanation
Not to eat flesh contributes to the continuance of life; therefore if a man eat flesh, hell will not open its mouth (to let him escape out, after he has once fallen in).

Tamil Transliteration
Unnaamai Ulladhu Uyirnilai Oonunna
Annaaththal Seyyaadhu Alaru.