Your television is flooded with commercials portraying milk as the consummate protector of strong bones and top health. Athletes, movie stars and other famous individuals help shout this message from the rooftops. But, according to research published October 28, 2014 in The BMJ, these advertisements may be sending the wrong message.
Milk is essential for survival and growth of developing young children, particularly breast milk, which provides complete and vital nutrients. Human milk and cow’s milk both contain the sugar lactose, but human milk also supplies the lactase enzyme necessary to digest lactose.
With the exception of humans, all mammals consume milk as long as it is necessary for growth and development. Humans ignore this natural progression and consume milk formulated for developing calves long into adulthood.
As we age, humans produce less of the digestive enzyme lactase, which helps digests the milk sugar lactose — the other sugar in cow’s milk is galactose. A significant number of the world population — up to 65 percent — is lactose intolerant, meaning they are unable to digest the milk sugar lactose. This inability to digest lactose leads to gastrointestinal discomfort like bloating, stomach cramps, gas and diarrhea.
Though advertised as a nutrient essential for strong bones, previous scientific research has produced conflicting results casting doubt on the importance of milk for the prevention of fractures. Other research has suggested that cow’s milk increases oxidative stress and chronic inflammation.
Armed with this knowledge, Swedish researchers designed a study to investigate milk’s effect on human health. Over 106,000 Swedish adults aged 39 to 74 were included in the study. Each study participant completed food frequency questionnaires for 96 common foods including milk, yogurt and cheese. Lifestyle information, education level and marital status were all included as factors in the study.
Fracture and mortality rates were tracked among men for a total of 11 years, whereas women were tracked for 20 years. What the researchers found was that milk consumption did not reduce fracture risk, and surprisingly women who drank three or more glasses of milk per day had a higher risk of death than those who limited their consumption to one glass daily. Men who consumed the most milk also had a higher mortality rate.
The researchers also observed a link between milk consumption and biomarkers of oxidative stress and inflammation. Consuming fermented milk products, like yogurt, produced the opposite effect, reducing fracture and mortality rates, particularly among women.
The study authors emphasize that their study does not prove cause and effect and only shows an association. They recommend further research to confirm their hypothesis that milk sugars may be responsible for the adverse health effects of cow’s milk.
For those who prefer not to consume cow’s milk, almond and rice milk may be viable alternatives.