How were you first alerted to the possible connection between UFAs and COVID-19 severity?
Singh: It was the similar patterns between COVID-19, a new disease with no treatment, and pancreatitis, an old disease, which we're currently studying. For example, obesity is a risk factor for both, and multi-organ failure can occur in both, although one disease starts in the lungs and the other in the digestive tract. And in either disease, severity is preceded by hypoalbuminemia and hypocalcemia. In addition, lipase elevation is linked to severity in COVID-19 and also mediates severity in pancreatitis.
The resemblances of the dietary patterns, clinical features, and autopsy findings for severe COVID-19 to those for severe acute pancreatitis were astounding! ...snip... How are these fats potentially lethal?
Singh: Humans have 1 to 5 kilograms of linoleic acid stored in fat. In this stored form it's safe, but it's released by lipases in pancreatitis and in COVID-19. The lethal dose of linoleic acid is 280 milligrams per kilogram -- just 23 grams for a person weighing 80 kilos. Similarly, in the case of oleic acid, only very low doses are needed for lethality.
Which dietary sources contain high levels of UFAs?
Singh: It's all related to composition based on double bonds in a long fatty acid chain with more than 12 carbons. Linoleic and oleic acid are the two most abundant UFAs in the human body, and linoleic acid has increased to now comprise more than 20% of our stored fat. Commonly consumed vegetable oils such as safflower, sunflower, and corn are all quite high in linoleic acid, while oleic acid makes up a large part of olive, canola, and peanut oil.
