In our last article, about a month ago, we wrote about the huge contribution to nutritional science in South Africa by Dr ARP Walker. Around the same time, another observant scientist/surgeon in Uganda was making some landmark observations. He is most famous for identifying the cause of a particularly disfiguring cancer, which was not uncommon in Uganda in those far-off days, the early 1950s.
Dr Denis Burkitt was an Irish surgeon based at the prestigious Makerere University Hospital in Kampala. As the main referral hospital for the country, he saw an inordinate number of cases of a particular lymphoma affecting children and young adults. As a good scientist he set out to elucidate the cause, and why it was so common. After years of research he established that it was caused by the Epstein-Barr (EB) virus. Because of the association of the disease with malaria he believed that the virus was spread by Anopheles mosquitoes, as with malaria. However, subsequent research has shown the association is that malaria causes massive overgrowth of B lymphocytes, in which genetic mutations occur causing the Burkitt’s lymphoma. The EB virus is spread via human saliva, and is very prevalent in central Africa.
But perhaps an even more important observation by Dr Burkitt was the major difference in the spectrum of diseases between people in rural Africa and in Western countries. He was a good friend of Dr ARP Walker and, together with two other mission doctors in East Africa, came up with the dietary fibre hypothesis relating to non-communicable diseases.
They found that common western diseases, like heart attacks, diabetes, bowel cancer, diverticulosis, gall stones and piles, were almost unheard of in rural Africa. In 1969, he published an article entitled “Related disease-related cause?”.
It was this finding that changed the course of his career. He began travelling around the world promoting his ideas, which were rather revolutionary in those days. People in rural Africa were consuming around 50 g of dietary fibre per day, compared to their Western neighbours who were only consuming around 15 g per day. Could it be possible for such a small difference, resulting from manufacturing and processing of food to have such a profound effect?
It is now universally accepted that he was right, and further research has progressed to show that dietary fibre, and a healthy gut microflora are vitally important for overall health. Gut bacteria feeding off the dietary-fibre produce many different by-products, perhaps the most important being short-chain fatty acids. These small organic acids have profound effects on the immune system, the integrity of the intestinal wall, the appetite, the hunger centres in the brain, control of blood pressure, blood glucose levels, regulation of blood cholesterol, and even mental function such as stress and anxiety.
What a legacy he and other observant scientists left to us. It is too bad that we haven’t applied their findings to our dietary choices. Perhaps conditions like ischaemic heart disease, diabetes, colon cancer and so on would be far less common than they are now.
- This health column is written by Dr Dave Glass, a retired obstetrician/gynaecologist living in Somerset West for just over a year. He is also chairperson of the South African Lifestyle Medicine Association (Salma). Glass, with a MBChB, FCOG(SA) and DipIBLM, has a passion for preventing and addressing the root causes of chronic diseases such as diabetes, heart disease, auto-immune diseases, obesity, dementia and cancer.
