Health & Wellness

Saturated Fats Are Bad for Your Liver

Too much fat in your liver can lead to diabetes

By Wendy Haaf

Photo: iStock/YelenaYemchuk.

All extra calories are not created equal—not when it comes to non-alcoholic fatty liver disease, an important risk factor for developing Type 2 diabetes.

In an experiment reported in the journal Diabetes Care, 38 healthy but overweight adults were randomly assigned to eat an extra 1,000 calories a day from one of three sources: saturated fat (in the form of butter, cheese, and coconut oil), sugar (from candy, a sugary drink, and orange juice), or unsaturated fat (largely from olive oil, pesto, and pecans). After three weeks, all three groups saw gains in accumulated liver fat; however, the increase was greatest in those on the saturated fat diet: they saw a 55% gain, versus 33% for sugar and 15% for unsaturated fat.

The extra-butter crowd were also worse off in two other ways: their bodies were less sensitive to insulin (a marker of diabetes risk) and they had higher levels of LDL (“bad”) cholesterol.