The new fat that's worse than trans fat

Better Nutrition, April, 2007 by Jack Challem

Just about everyone knows that trans fats are bad news when it comes to boosting cholesterol and heart disease risk. But their replacement--known as interesterified fats--are even more dangerous, according to a study in the January 2007 journal Nutrition & Metabolism.

Kenneth C. Hayes, PhD, of Brandeis University, Waltham, MA, and some colleagues in Malaysia put 30 healthy subjects on three diets, each for one month. The diets were the same except that they alternately included 30 percent saturated fat, partially hydrogenated soybean oil, or interesterified soybean oil.

Like trans fats, interesterified fats raised blood levels of the "bad" LDL cholesterol and lowered the "good" HDL cholesterol. But the real shock came when the researchers looked at blood sugar levels.

After one month of consuming the interesterified fats, the subjects' fasting blood sugar shot up by 20 percent, and their post-meal blood sugar skyrocketed by 40 percent (compared with the saturated-fat diet). Hayes noted that these changes amounted to prediabetes.

Meanwhile, the Food and Drug Administration has given food companies and restaurants the go-ahead to use interesterified fats. Watch out for any of these terms on food ingredient labels, interesterified soybean oil, interesterified vegetable oil, fully hydrogenated oil, high in stearic acid, or stearate rich.