The Nation's Health

Butter: Just because it's low-carb doesn't mean it's good

The diet I advocate in the Track Your Plaque program to gain control over the factors that lead us to coronary plaque and heart attack is a low-carbohydrate diet. We begin with elimination of wheat, cornstarch, oats, and sugars in the context of an overall carbohydrate-reduced diet. We refine the program by monitoring postprandial (after-meal) glucoses.

But not everything low-carb is good for you. Fried sausages, for instance, are exceptionally unhealthy, despite having little to no carbohydrates.

An emerging but potentially very powerful issue is that of Advanced Glycation End-products, or AGEs. There are two general varieties of AGEs: endogenous (formed within the body) and exogenous (formed in food that is consumed).

Endogenous AGEs form in the body as a result of high blood glucose, i.e., glycation. When exposed to any blood glucose level of 100 mg/dl or greater, some measure of glycation will develop due to a reaction between glucose and various proteins, e.g., proteins in the lens of the eye, forming cataracts over time.

Exogenous AGEs form in food, generally as a result of heating to high-temperature. (AGEs is really a catch-all term; there are actually a number of reactions that occur in foods, not all of them involving sugars. However, the "AGE" label is used to signify all the various related compounds. The values quoted here are from Dr. Helen Vlassara's Mt. Sinai Hospital laboratory; reference below.)

Beef cooked to high-temperature yields plentiful AGEs. One gram of roast beef, for instance, contains 306,238 units. This means that an 8-oz serving yields 13.8 million units AGEs. Compare this to a boiled egg with 573 units per gram, raw tomato with 234 units per gram.

Butter contains an impressive 264,873 units AGEs per gram, the highest content per gram in the entire list of 250 foods tested in the Mt. Sinai study. A couple pats of butter (10 g) therefore contains 2.64 million units. A stick of butter that you might add to cake batter to make a cake therefore yields 30 million units of AGEs.

So there's nothing wrong with the fat of butter. It's AGEs that appear to be responsible for the endothelial dysfunction/artery-constricting, insulin-blocking, oxidation and inflammation reactions that are triggered. Among all of our food choices, butter is among the worst from this viewpoint.

Throw in the peculiar "insulinotrophic" effect of butter, and you have potent distortion of metabolic pathways, courtesy of the butter on your lobster.

(AGE data from Goldberg 2004. In this analysis, carboxymethyllysine was the marker used for AGE content.)

Incidentally, the new Track Your Plaque diet will soon be released as chapter 9 of the new Track Your Plaque book on the website.