Religious texts/traditions often suggest that we should limit meat consumption. These suggestions generally predate modern science, yet seem to fairly frequently be rooted in the idea that meat -- or certain meats -- are "unclean."
Matthew 5:6 -- "Blessed are those who hunger and thirst for righteousness, for they will be filled."
Matthew 6:16 -- “When you fast, do not look somber as the hypocrites do, for they disfigure their faces to show others they are fasting. Truly I tell you, they have received their reward in full. 17 But when you fast, put oil on your head and wash your face, 18 so that it will not be obvious to others that you are fasting, but only to your Father, who is unseen; and your Father, who sees what is done in secret, will reward you."
A little more detail as to context: https://en.wikipedia.org/wiki/Matthew_6:16
Fasting has been beneficial to my incurable medical condition. I'm quite encouraged by the association between fasting and religion. To me, it suggests there is something fundamentally wise about the practice and important to human health.
That may be the interpretation under Judaism, but outside of Judaism I think people can take a decent stab at understanding.