By Gatonye Gathura
Fermented milk, including ‘mursik’ does not cause cancer of the large intestine but sausages, alcohol, salami and eggs are a risk, shows a new study at Kenyatta National Hospital.
In the past studies have accused traditionally fermented milk for high rates of cancers of the digestive track, especially in the Rift Valley but a new study says the products may actually help against the disease.
Fermented milk has been associated with high presence of the bacteria Streptococcus infantarius (Sii) suspected to cause cancers of the digestive system.
However a new study at Kenyatta National Hospital (KNH) suggests fermented milk may interact with the suspect bacteria to protect consumers against tumors of the colon and rectum called colorectal cancer.
The team studied 413 adult individuals attending KNH for colon examination. The participants included groups with colorectal cancer, other colon problems and a comparison group which had healthy large intestines.
The authors now report that all types of fermented daily products do not cause colorectal cancer in fact some like the commercial yoghurt was found to reduce the risk.
Traditional fermented milk such as the famous mursik of the Kalenjin, commercial sour milk such as the mala or lala were not associated with an increased risk of colorectal cancer.
“In fact the consumption of commercial yoghurt showed a slightly but significant decrease risk of developing colorectal cancer,” says the study.
Also absolved from blame is the traditional sour cereal based porridge now a popular breakfast product in many urban healthy foods restaurants.
The product is also popular with the mobile ‘mama uji’ vendors to be found serving groups of workers in construction sites, boda boda and matatu pick up points.
The study, published eleven days ago (25th October 2017) further investigated other foods or lifestyles that may have led to some of the KNH patients developing colorectal cancer.
The researchers report that the consumption of any type of sausages, that is from chicken, beef or pork, beef salami and eggs increases the risk to this cancer.
Colorectal cancer which affects the large intestines is the seventh most prevalent tumor among women and men in Kenya.
The study appearing in the journal Acta Tropica was carried out by a team from the University of Nairobi and prominent institutions from Switzerland, Germany, Ivory Coast and France.
The research funded by the University of Nairobi, UBS Optimus Foundation Switzerland and Wellcome Trust of the UK also recorded a small risk in white tea and coffee in development of colorectal cancer.
“Adding plain milk to tea or coffee showed slightly elevated risks for colorectal cancer whereas tea without milk and coffee without milk did not,” says the study but calls for more research on this finding.
The researchers investigated the kind of diets consumed by the study participants and concluded that processed meat, alcohol and smoking put one at highest risk of developing colorectal cancer.
“Foods that were significantly associated with colorectal cancer in our study, were eggs, pork sausages and beef salami.”
Other foods found with potential risk towards colorectal cancer, the study says were chicken sausages, poultry with skin, processed meat, pork and roast beef.
The team also identified alcohol consumption and smoking as major risk factors of developing colorectal cancer.
Other factors found to put Kenyans at an increased risk of developing colorectal cancer were being over 50, living in rural areas owning or being in close contact with livestock.
Past studies have linked traditionally fermented milk to the development of cancers of the digestive system including those of the throat or esophageal cancer.
Mursik the traditional fermented milk of the Kalenjin of the Rift Valley has been studies extensively for its possible role in the development of throat cancer.
A 2013 study by Dr Kirtika Patel of Moi University Moi Teaching and Referral Hospital (MTRH) reported throat tumours as the leading cancer in males at the facility. It was also the third after cancer of cervix and breast in females in all cancers reported at the facility.
The study has linked smoking, snuff use, alcohol, cooking with charcoal and firewood, taking hot beverage, and use of mursik to throat cancer.
The authors suspected some compounds found in the charcoal powder used in processing mursik and some bacteria in the fermented milk to the development of throat cancer in consumers.
Other traditionally fermented milk products in Kenya include the amabere amaruranu of the Kisii, kule naoto of the Maasai and the suusa from North Eastern Kenya.
By Kenya, Switzerland, Germany, Ivory Coast and France
Investigated role of fermented milk in colorectal cancer
Fermented daily products such as mursik, mala, lala and yogurt do not cause colorectal cancer
All types of processed meat, eggs, alcohol and tobacco are a risk to colorectal cancer
Study investigated 413 patients at Kenyatta National Hospital
Patients with colon problems had higher rates of the bacteria Sii