Byron Bay cafe, The Roadhouse, serving birthing breast milk smoothies

The Colostrum Shake will set you back $8 at the Roadhouse Cafe. Photo / Instagram

A cafe in northern NSW is turning heads with its "nurturing" smoothies that contain colostrum.

The Roadhouse, tucked in the town of Byron Bay, serves up smoothies made with the thick, yellow liquid, excreted from the mammary glands of mammals straight after they give birth.

Known as the "Colostrum Shake", the cafe blends up the "cool tonic" with coconut water, for just $8.

The cafe introduced the world to its colostrum smoothie in a post, uploaded to its Instagram account several months ago, news.com.au reported.

Describing the ingredient as "immune milk", the Roadhouse claims the colostrum is Mother Nature's first food for all mammals.

Colostrum is formed by a mammal immediately after birth. Photo / Getty

The post attracted hundreds of likes and comments, with some people describing it as "sick".

Many couldn't wrap their heads around the idea of drinking the liquid, which also leaks from women's breasts in the first 2-5 days after birth.

It's also referred to as "liquid gold" because of it's disease-fighting agents, which is why Roadhouse promoted it.

Despite some initial anxiety from followers, it was finally determined that the cafe was using cow colostrum, rather than human colostrum, after reading that the shake was "Udderly delicious".

The thick, yellow colostrum is said to be extremely good for newborns. Photo / Getty

Still, many commented that the addition was unnecessary and "so f**king weird!".

"WTF haha, this is sick," another commenter wrote.

But others couldn't see what the big deal was, claiming the provocative post was "clever marketing".

"Each to their own," one person wrote.

Another added: "What's the difference?"