Germans have been drinking less and less milk for years. According to the Federal Information Center for Agriculture (BZL), the per capita consumption of cow's milk fell last year to an average of just 47.8 kilograms (minus 2.2 kilograms). This is the lowest milk consumption since the start of all-German statistics in 1991. Nevertheless, milk is on the table in many households every day and there are a lot of assumptions about milk. But what is true and what is perhaps not? A fact check on International Milk Day on June 1st:
Claim: Warm milk helps you fall asleep.
Rating: Not scientifically proven.
Facts: Grandma Hilde recommended it to the offspring, as did grandmother Emine: warm milk with honey before going to bed. The Stiftung Warentest, however, rates the old home recipe as a "nice dream" that stems from the fact that milk contains tryptophan. This amino acid serves the body as a precursor for the hormone melatonin, which controls the sleep-wake cycle. However, the amount of tryptophan in milk is comparatively low and the sleep-promoting effect of even higher-dose preparations is poorly documented.
In a 2020 meta-study, Japanese researchers evaluated various studies on the effects of milk and milk products on sleep. Their result: A balanced diet including dairy products can improve the quality of sleep. However, the significance of some evaluated studies was low, according to the researchers. And the fact that evening milk was an effective aid to falling asleep could not be proven in general by any study.
However, that doesn't mean the nightcap is definitely useless. Psychological effects are quite conceivable: milk and honey are reminiscent of security and childhood. The ritual of an evening milk as such can also have a calming effect.
Claim: Cleopatra owed her beauty to milk baths.
Facts: The economy uses the myth in many different ways and successfully: Hotels offer baths in milk and honey, which, like that of Egypt's legendary queen, are said to make the skin firm and radiantly beautiful. Cosmetics relate their ingredients to substances that are said to have been used since ancient times and advertise accordingly with Cleopatra's name or likeness. There is hardly any actual evidence of their beauty, and even less of their bathing habits.
One might think of the Hollywood image of Elizabeth Taylor as Cleopatra bathing in a milky broth when it comes to the secret of her beauty. The Roman naturalist Pliny left a clue to the actual extravagance when he related in the first century AD that the emperor's wife Poppaea always carried 500 pregnant donkeys with her, in whose milk she bathed. In translations there is also talk of mare or sheep's milk. But since beauty can hardly be evaluated objectively, the secret remains exactly that - a secret.
Claim: Hippopotamus milk is pink.
Facts: It's one of the popular urban legends of the internet that almost everyone has stumbled upon at some point: the supposedly uniquely colored hippo mother's milk. Even the renowned magazine "National Geographic" spread the claim on Facebook in 2013 as "Friday Fact". In fact, the hippos do not feed on strawberry milk.
The US fact check portal "Snopes" has examined the claim and comes to the verdict: not true. Perhaps the rumor goes back to the fact that hippos excrete a reddish, sweat-like hipposudoric acid that protects their skin from the sun's rays. If this mixed with the white of breast milk, a pink-colored substance might result.
However, British biologist David Wynick cautions: "As the pigment is acidic, I would assume it wouldn't bond well with the milk." He has not been able to find any evidence that it passes into breast milk, causing it to turn pink.
A video released by the Cincinnati Zoo showing nurses milking a hippopotamus also shows no evidence of breast milk coloring.