Do not eat forbidden fat.
“Do not eat forbidden fat of ox, goat or sheep “Vayikra 7: 23
If someone ate an olive size amount of forbidden fat from one of these 3 animals, if deliberate he deserves spiritual severance, if unintentionally he would be required to bring a sin offering.
The fat of a ram’s tail is permissible and not all that is connected with an offering is called forbidden fat, only the fat on the entrails, kidneys and the loins.
Sinews in fat are forbidden.
The fat of untamed kosher animals is permitted.
This applies in all places at all times for men and women.