3 cows on a blue sky background - featured image for the news article around multiple sclerosis and beef

Multiple sclerosis and beef – what’s the link?

Is there a connection between cow products such as milk and beef and multiple sclerosis? Ian Cook investigates

Dairy has long been considered by some as the environmental factor that may trigger multiple sclerosis (MS). The reason is simple – MS is far more common in countries where cow’s milk is drunk. Recently, Nobel Prize winning researcher and virologist Harald Zur Hausen widened this theory to look at beef and MS too.

Zur Hausen made several interesting observations about the connection between cow products and MS in academic papers published in 2014 and 2021. In the 2014 paper he said, “Epidemiological data point to the involvement of a cow milk factor in the aetiology of multiple sclerosis (MS).” In the 2021 paper he went further, suggesting that MS is associated with the consumption not just of milk but beef, too.

DNA clue

He noticed isolated ring-shaped DNA molecules closely related to bovine meat and milk factors (BMMF) from dairy and cattle blood are present in the brain lesions of patients with MS. Zur Hausen was amazed at his findings. As he put it, “The result was electrifying.”

Zur Hausen didn’t go so far as to say that beef and milk cause MS. Rather he thought MS is caused by a double infection of brain cells by the Epstein-Barr virus (EBV) and the presence of BMMF in those EBV infected brain cells.

Zur Hausen is the latest in a long list of researchers to make a connection between MS and cow products, although traditionally most researchers have limited their attention to milk rather than beef. In 2018 a German academic Stefanie Kürten from University Hospital Bonn looked into a link between cow’s milk and MS. “We injected mice with different proteins from cow’s milk. We wanted to find out if there was a constituent that they were responding to with symptoms of disease.”

Scientific evidence

Kürten and her group did indeed find exactly what they were looking for. When they administered a cow’s milk constituent called casein together with an effect enhancer to the mice, they went on to develop neurological disorders. Electron microscopy showed damage to the insulating layer around the nerve fibres, the myelin sheath.

The insulating sheath was massively perforated in the mice, apparently triggered by casein administration. “We suspected that the reason was a misdirected immune response, similar to that seen in MS patients,” explains Rittika Chunder, a postdoctoral fellow in Prof. Kürten’s research group. “The body’s defences actually attack the casein, but in the process, they also destroyed proteins involved in the formation of myelin.”

EBV link

Casein is present in beef as well as cow’s milk. Clearly it is possible that casein is part of the process that causes BMMF to be in the brain lesions associated with MS. But the question remains – how does all this tie in with the exposure to the Epstein Barr virus?

In his 2021 paper, Zur Hausen hypothesized that EBV is reactivated in MS and then the BMMF multiply and are eventually converted into proteins which cause auto-immunity, leading oligodendrocytes to malfunction, which leads in turn to the destruction of myelin.

Geographical evidence

According to Zur Hausen and Kürten, the case against cow products is a strong one but if further justification were needed, a paper published in Multiple Sclerosis Journal in 2016 found that one of the biggest cattle-rearing areas in South America, Córdoba, Argentina, also has the highest prevalence of MS in Latin America with 88 cases per 100,000 inhabitants.

This prevalence dwarfs that of the Chilean city of Punta Arenas at the very Southernmost and least sunny tip of the continent, which is known for its sheep farming, and has a prevalence of MS of just 14 per 100,000, suggesting that cow products may be a far more powerful predicator of MS even than latitude and lack of sunlight.

My own experience

Interestingly when I carried out a 93 food IgG (Immunoglobulin) food intolerance screening test I found that cow’s milk was the animal product that I had the highest level of sensitivity to, and beef was the meat I was most sensitive to. While I would be the first to admit that this is not conclusive proof that cow’s milk and meat are the environmental factor that have played a part in my MS, Professor Kürten’s work and the more recent work by Zur Hausen has made me think it is arguably time for all MSers, myself included, to consider cutting out cow’s milk from my diet and even cutting out beef too.

If further justification for this radical change to my diet were needed it would come not from my own anecdotal evidence or classical medical research, but from a study of occupational risks and MS. The study was carried out by a Danish pension provider PensionDanmark into critical illness insurance cover and those occupational groups most likely to claim it.

This research showed that the frequency of MS among ‘dairy operators,’ was twice as high as the rest of the study’s population. It’s hard to think of what more proof you need when it comes to reasons for giving up cow’s milk. The evidence against beef is growing but when it comes to giving up cow’s milk, I would say the evidence is already there. Given the fact that beef has only been linked to MS relatively recently, it may be just a matter of time before it is next on the banned list for enlightened MSers. I am sure that time will come and come soon.