求翻译：严格素食者最容易缺乏的营养素是铁、锌和维生素B12。这是因为，肉类、内脏和动物血是铁的最佳来源，而一般素食中的铁较难被人体吸收；锌在动物性食物当中比较丰富，而且吸收率高；维生素B12则只存在于动物性食品(包括蛋和奶)、菌类食品和发酵食品中，一般素食不含这种维生素。此外，严格素食者的食物当中几乎没有维生素A和维生素D，是什么意思？

Strict vegetarians are most likely to lack the nutrients iron, zinc and vitamin B12. This is because, meat, offal and animal blood is the best source of iron, and the general difficult to be vegetarian in the body to absorb iron; zinc in animal foods rich in them, and absorption rate; vitamin B12 fo

strict vegetarians the most vulnerable to lack of nutrients, iron, zinc and Vitamin B 12. This is because the meat, offal and animal blood is the best source iron, and iron in the vegetarian food in general is more difficult to be absorbed by the body; zinc in animal food, more plentiful, and 12 hig

The strict veggie most is easy the deficient nutrient is the iron, the zinc and Vitamin B12.This is because, the meats, the internal organs and the animal blood are the hard best origins, but in the common vegetarian diet iron is difficult by the human body absorption; The zinc quite is rich in the

Strict vegetarians most lack nutrients are iron, zinc, and vitamin B12. Because meats and offal and animal blood is best sources for iron, iron in vegetarian more difficult absorbed; zinc in animal foods relatively rich and absorption rate high vitamin B12 only exists in animal food (including egg a

Vegan most likely lacking in nutrients are vitamin B12 iron, zinc and. This is because the meat, offal and animal blood is the best source of iron, but generally of iron in vegetarian diet is more difficult to be absorbed by the human body; zinc in animal foods relatively rich, and high rate of abso