Human beings are peculiar in routinely drinking the milk of another species. After all, milk is meant as the first food for a very young baby animal. As such, cow's milk is the ideal first food for baby cows, not necessarily for people (baby or otherwise).
On the other hand, most mammal milks are very similar in composition to each other, and it's undoubtedly true that cow's milk provides most of the nutrients (it's a notably too low in iron) that children and adult people need. And it isn't especially high in sugar, fat, salt, strange additives or anything else obviously 'unhealthy' for you. So compared to a lot of other things we might be eating, it's a pretty 'good' food.
The only really sound arguments against milk are biological and epidemiological: many of the world's adults are genetically incapable of digesting it: intolerant to either the sugars (lactose) or proteins (casein). Moreover, there are several research studies which find disturbing correlations: osteoporosis and Type I diabetes seem more common in countries that drink the most cow's milk. A diet high in milk products (and gain foods) may encourage an acid imbalance in the body, effectively leaching calcium out of our bones, to raise the risk of osteoporosis. The link to diabetes mostly applies to babies on formula milk. It's thought that early exposure to cow's milk may sometimes trigger the immune system to attack the pancreas, leading to damage in the body's future ability to produce insulin.
There are a lot of other myths about why milk might be bad for you, most of which are linked to the risk of contamination; but these dangers may be similar for other foods, too.
On the other hand, most mammal milks are very similar in composition to each other, and it's undoubtedly true that cow's milk provides most of the nutrients (it's a notably too low in iron) that children and adult people need. And it isn't especially high in sugar, fat, salt, strange additives or anything else obviously 'unhealthy' for you. So compared to a lot of other things we might be eating, it's a pretty 'good' food.
The only really sound arguments against milk are biological and epidemiological: many of the world's adults are genetically incapable of digesting it: intolerant to either the sugars (lactose) or proteins (casein). Moreover, there are several research studies which find disturbing correlations: osteoporosis and Type I diabetes seem more common in countries that drink the most cow's milk. A diet high in milk products (and gain foods) may encourage an acid imbalance in the body, effectively leaching calcium out of our bones, to raise the risk of osteoporosis. The link to diabetes mostly applies to babies on formula milk. It's thought that early exposure to cow's milk may sometimes trigger the immune system to attack the pancreas, leading to damage in the body's future ability to produce insulin.
There are a lot of other myths about why milk might be bad for you, most of which are linked to the risk of contamination; but these dangers may be similar for other foods, too.