Even if you’re not a fan of McDonald’s burgers, fries, or food offerings of any kind, you have to admit the fast food chain knows how to make a pretty tasty shake. Thick and creamy, sipping on a McDonald’s shake can instantly bring back those feelings of happy contentedness you felt as a child, and in Japan part of the reason might be that the experience is designed to make you feel like a baby sucking down a meal of breast milk.

Japanese Twitter user @ritsu_mmsh recently sent the following tweet to his followers, which claims that McDonald’s shakes, called “Mc Shakes” in Japan, are designed to be drunk at the same speed as an infant nurses.

But apparently this was already common knowledge to those with an interest in product design and/or breasts. As a matter of fact, several point to a series of books written by McDonald’s Japan founder Den Fujita, specifically Den Fujita’s Business Strategies 2: Overwhelming Business Strategies, as their source.

Fujita is quoted as saying within its pages that:

“When humans drink something, the speed that produces the most delicious feeling is the speed at which babies nurse…McDonald’s straws are designed so that when used with a shake, the speed will be the same as that of an infant drinking breast milk.”

Online reactions to this revelation included:

“Be right back-going to McDonald’s for a shake!” “I’m gonna go pick up a vanilla one.” “McDonald’s is going to be packed with customers.” “They should make a cup lid with a nipple on it.” “No no McDonald’s speed is way off. If you go nurse you can totally tell.”

We don’t have sharp enough memories or perverted enough tastes to confirm or disprove that last comment. It’s also not clear whether this unusual design choice is unique to Japanese McDonald’s branches, or if franchises all around the world use the same size straws. Either way, though, this is one more reason to swing by the Golden Arches in the Land of the Rising Sun, even if they don’t happen to be serving one of their Japan–exclusive flavors at the time.

▼ Don’t worry, we’re sure the straw fits fine in these anime girl figure cups.

Sources: Twitter/@ritsu_mmsh, Yahoo! Japan Chiebukuro, Naver Matome, Jin

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