Interesante artículo de octubre de 2018 mencionando los beneficios en la salud, el medio ambiente (reduciendo la principal causa de emisión de gases con efecto invernadero, deforestación y consumo de agua) así como los motivos éticos para no comer alimentos de origen animal (carnes, incluyendo pescados, huevos ni lácteos)
Between 2002 and 2007, 73,000 Seventh Day Adventists, a religious group in America, participated in a study of eating habits. The 27,000 vegans and vegetarians among them had significantly lower mortality rates.
Large studies have shown that people who eat a lot of red meat have higher overall mortality rates. … Eating a lot of processed meat is linked to colorectal cancer. The evidence on this seems clear enough for various authorities to recommend limits to the total ingestion of red meat.
In 2016 a study by Marco Springmann and colleagues at the University of Oxford found that, globally, a transition to well-balanced vegan diets might result in 8.1m fewer deaths a year. Universal vegetarianism would avoid 7.3m deaths.
Mr Springmann and his colleagues calculated that in 2050 greenhouse emissions from agriculture in a vegan world would be 70% lower than in a world where people ate as they do today
Raising cattle produces seven times more in terms of emissions per tonne of protein than raising pork or poultry does, 12 times more than soya and 30 times more than wheat.
The vegans also abstain from milk and eggs because there, too, they see a lot of exploitation, death and suffering. In dairy herds calves are typically taken from their mothers within 24 hours, compared with the nine months to a year they would suckle if left to themselves. Male calves are killed or reared for meat. In industrial egg-production day-old male chicks are killed and simply discarded. Even if one keeps strictly to meat, though, the death toll involved is immense. Over 50bn farm animals are killed for meat every year.
Animals’ brains contain regions clearly analogous to those correlated with consciousness, perception and emotion in humans. They definitely feel pain, and some can both express preferences and, it would appear, hold beliefs about the preferences of others. That would seem to have some moral salience.