DR Michael Greger, founder of nutritionfacts.org, talks to us about the role of a plant based diet in relation to type two diabetes.
When it comes to what we eat, it feels difficult to know who to believe. One article claims one thing, and the next claims another.
Physicist Dr. Michael Greger is also the author of the health and nutrition book ‘How Not To Die’, which instantly became a New York Times Best Seller. The book has become something of a holy grail within the plant based community, with a wealth of information on how switching to a plant based diet can be beneficial to human health.
We’re excited to bring you Dr. Greger’s thoughts each issue to dispel confusion over many of the misnomers floating around, so that you can feel confident when explaining your plant based diet to friends, family and colleagues.
First up is type two diabetes.
After the age of about 20, we may have all the insulin-producing beta cells we’re ever going to get. Beta cells are the cells inside the pancreas that produce, store and release insulin — the hormone which helps regulate sugar levels in the blood. So if we lose these beta cells, we may lose them for good.
We know that these crucial beta cells may be killed by excessive fat consumption. If you expose the insulin-producing beta cells in the pancreas to fat in vitro, they suck it up and then start dying off. As the fat starts to breakdown, products of this process interfere with the function of beta cells and this ultimately leads to beta cell death. Therefore, chronic increases in blood fat levels can be harmful to our beta cells, insulin production and pancreas.
It’s not just any fat; it’s saturated fat. Fats in olives, nuts, and avocados provides a slight increase in a protein which damages beta cells, but saturated fat really elevates this protein leading to significant beta cell death.
Simply, saturated fats are harmful to beta cells.
Bad cholesterol (LDL) can also cause beta cell death as a result of the formation of free radicals — unpaired electrons in the body associated with the development of cancer, Alzheimer’s and Parkinson’s.
Diets rich in saturated fats not only may contribute to obesity and insulin resistance, but the increased levels of circulating free fats in the blood (non-esterified fatty acids, or NEFAs) may also cause beta cell death and may thus contribute to the progressive beta cell loss we see in type two diabetes. These findings aren’t just based on test tube studies. When researchers have infused fat directly into people’s bloodstreams, they can show it directly damaging pancreatic beta cell function. The same occurs when we ingest it.
Type two diabetes is characterized by weaknesses in both insulin production and insulin action, and saturated fat appears to impair both of these vital functions. Researchers showed saturated fat ingestion reduces insulin sensitivity within hours of consumption. This implies saturated fat impairs beta cell function as well, again just within hours after going into our mouth. Unfortunately, saturated fat isn’t just toxic to the pancreas.
Saturated fat has been found to be particularly toxic to liver cells, contributing to the formation of fatty liver disease. If you expose your liver cells to animal fat in vitro, a third of them die. If you expose human liver cells to plant fat, though, nothing happens. This may explain why higher intake of saturated fat and cholesterol are associated with non-alcoholic fatty liver disease.
However, it is not all doom and gloom. If you reduce the proportion of saturated fat in your diet, the knock-on effect on insulin levels is substantial, regardless of how much belly fat we have, and by reducing saturated fat consumption, we can help interrupt the processes which lead to beta cell death.
So what causes diabetes?
Simply, the consumption of too many calories rich in saturated fats. It is true that not every person whose diet is high in saturated fats will develop diabetes; it is also true that not every smoker will develop lung cancer. However, the likelihood of development is greatly increased by these lifestyle choices and saturated fats are currently considered the most significant cause of type two diabetes.
For more information on Dr Greger’s work head to: nutritionfacts.org