A diet that lacks meat also lacks important nutrients

The argument

Many important nutrients essential to the body and to health overall are found in high quantities in meat. However, they are hardly ever naturally present in foods aside from meat, or if they are, are only found in low quantities or cannot be absorbed easily due to the source from which they're found. These nutrients include vitamin B12, vitamin D, omega-3 fatty acids, zinc, and iron. Vitamin B12 and iron help prevent anemia among other functions, vitamin D maintains bone health, omega-3 fatty acids are important for hearth health, and zinc helps the immune system and metabolism. Going on vegetarian diet could mean lacking these important nutrients, which could adversely affect the body. Further, a vegetarian diet could pose to be dangerous for pregnant mothers. Without careful planning and awareness, nutrient deficiencies as a result of a vegetarian diet could lead to maternal undernutrition and even impaired fetal growth.

Premises

Counter-arguments

Several of the nutrients listed are not meat-dependent, so the premise overstates its case. Vitamin D comes principally from sunlight and fortified foods, and meat is a poor source of it. Iron is present in legumes, tofu, wholegrains, nuts and dark leafy vegetables, and its absorption improves substantially when vitamin C is eaten in the same meal. Zinc is found in legumes, seeds, nuts and wholegrains. The long-chain omega-3s are the genuine gap, and they come from oily fish rather than from meat — so a fish-eating diet and a meat-eating one differ precisely here. The diet actually at issue is also vegetarian rather than vegan, and so includes eggs and dairy, which supply B12 and calcium; B12 is the one nutrient requiring supplementation on a fully plant-based diet, and it is largely covered by the diet described. The argument also establishes that a poorly planned vegetarian diet risks deficiency, which is not the same as a disadvantage of vegetarianism. Badly planned omnivorous diets produce deficiencies too, and iron deficiency is common among menstruating women who eat meat. The body concedes as much when it qualifies the pregnancy claim with "without careful planning and awareness" — major dietetic associations hold that appropriately planned vegetarian diets are adequate at all life stages, including pregnancy, lactation and infancy. Since the question is posed as pros and cons, an accounting must finally weigh these planning requirements against the lower saturated fat and higher fibre intakes the same diets typically deliver.

Rejecting the premises

[Rejecting P1] Several nutrients named are not meat-dependent: vitamin D comes chiefly from sunlight and fortification rather than meat, iron and zinc are present in legumes, wholegrains, nuts and seeds with absorption improved by vitamin C, and long-chain omega-3s come from oily fish rather than meat. [Rejecting P2] The diet at issue is vegetarian and so includes eggs and dairy, which supply B12 and calcium — the nutrient that genuinely requires supplementation on a fully plant-based diet is largely covered here. [Rejecting P3] The premise's own qualification, "without careful planning and awareness", concedes the risk is of poor planning rather than of vegetarianism, and major dietetic bodies hold appropriately planned vegetarian diets adequate at all life stages including pregnancy.