It is not the milk that is bad for the environment, but the cows themselves. So, yes, milk is bad for the environment.
One cow will produce 220 pounds or almost 100 kg of methane per year. Methane is of course decidedly bad for the environment, having 28 times the potency in comparison to carbon dioxide, despite its shorter life span.
It is true that cows are kept not just for milk, but also for meat. There are indeed more beef cattle kept in the United States than dairy cattle, but the methane effects of the dairy cattle alone are staggering due to the large numbers kept.
As well, dairy cattle were recently determined to be at a higher welfare risk than beef cattle, which leads us to the addition of ethical concerns in the conversation of cows.
A discussion of what is ‘bad for the environment’ can of course be opened up beyond climate change and land destruction factors to the mistreatment of animals. It is no secret that cattle can be severely mistreated as they are slaughtered for beef, but dairy cattle are just as, if not more mistreated than those that humanity farms to kill for their meat.
This is largely due to the higher level of intervention by humans in dairy cows lives. They are meddled with regularly during milk collection, as well as housed indoors for at least part of the year in some cases, with an even higher level of intervention from humans during that time. This is in addition to poor genetic selectiveness by humans leading to larger health problems, as well as the practice of removing calf from mother earlier on in the milking process. The milk a cow produces is of course naturally meant for their calves and not human consumption.
How to make this better for the environment?
Well, there are a wide variety of plant based milks available now as we shift into a new area of decidely not needing cow milk.
Plant based milks range in ingredients and taste, as well as nutrients included. However most plant based milks are fortified with a range of vitamins, iron, calcium, and sometimes protein as well. It is important to choose the correct plant based milk that would supplement your needs.
Although plant based milks do not support animal cruelty or extreme methane production, they can hurt the environment in other ways. Some plant based milks over use water in their production, or source products from far away. However, none of them have the environmental impact of methane. As always, do your research into the impacts of companies before purchasing their products, and try to buy local.