People with multiple sclerosis (MS) should stop drinking milk.
Milk—plus other dairy products such as yoghurt and cheese—can make the symptoms worse, say researchers from the University of Bonn.
Even for people without the condition, cow’s milk can mimic the devastating effects of MS, causing neurological damage by attacking the myelin, the insulating layer around the nerve fibres.
With multiple sclerosis, the body’s immune system destroys the myelin sheath, and in experiments on laboratory mice the researchers discovered that casein, a protein in cow’s milk, had the same effects. The researchers think that in breaking down the casein, the immune system also destroys myelin.
To check if similar effects would be seen in people, the researchers injected casein antibodies into human brain tissue. The antibodies accumulated in cells responsible for myelin production.
The immune response appears to focus on the ‘B’ white blood cells, and other researchers have noted a strong reaction to casein in MS sufferers. It’s thought they may have developed an allergic reaction to the protein when they were younger.
Although they can’t be sure that casein affects all MS sufferers, the researchers discovered it certainly makes symptoms worse in those who are allergic to milk.
(Source: Proceedings of the National Academy of Sciences, 2022; 119; doi: 10.1073/pnas.2117034119)