The Low Fat Myth: Why A Fat-Deficient Diet Could Prevent a Slim Waistline

At some point, most people have set a New Year’s Resolution to improve some aspect of their health, wellness or fitness. We all know it’s January when every gym in America is offering a New Year’s Special. Navigate through any aisle at the supermarkets, and you’ll see altered packaging of the same old “health foods.” This time around, however, the nutritional value is “improved” with 50 percent less of that substance that we’re programmed to fear and avoid like the plague: F-A-T.

The three-letter word has been demonized my entire adult life as an artery-clogging taboo. But it wasn’t always that way. In fact, your grandparents might have thought you were crazy for thinking so when they were children. There are a number of theories as to when the sentiment shifted.

One popular notion traces back to the 1950s when a physiologist named Ancel Keys conducted a study that correlated dietary saturated fat consumption to coronary heart disease mortality. The study, more commonly known as the Seven Countries Study, is extremely flawed because of the sheer number of confounding variables that were not accounted for in the study. The data collected was not even from an experiment that controlled subjects’ diets, but rather from national nutritional surveys.

Take France for example. Their incidence of heart disease is about half of that in America, yet the French are widely known for their high saturated fat intake. This observation is commonly referred to as the French paradox. The Diet-Heart Hypothesis coined by Keys then is generally the same one medical practitioners still herald to this day.

Though many scientists criticized Keys for his findings, most people in the United States already severely restricted their saturated fat intake by the 1960s. People were not only told to avoid the tasty substance, but their doctors even started telling them fat consumption would cause them to develop heart disease, high blood pressure or atherosclerosis.

This is just one of the countless instances where society drew conclusions before fully understanding the bigger picture. In a 2007 Stanford study published in the Journal of the American Medical Association, overweight women were randomly assigned to follow four popular weight-loss diets. The group that consumed high-fat and high-protein diets lost more weight and experienced more favorable metabolic effects than those that consumed a high-carbohydrate one.

The important takeaway is that the source of the saturated fat is a vital factor in determining whether it can have deleterious effects on health, not necessarily because it’s saturated. After all, not all saturated fats were born equal. In addition, the advice does not necessarily hold true for all types of fats. Medical data still suggests, for example, trans fats are detrimental to our health because of its incorporation into the body’s cellular membranes.

The bottom line is that some fats can actually help, not harm us in our journey of reaching our desired health goals. It satiates us, keeps us full for longer and provides us with a fulfilling energy source. This isn’t to say you should open the floodgates and only consume saturated fats. The primary issue is severely restricting the macronutrient in the quest to meet desired dietary objectives.

So the next time someone tells you to throw down something because the package doesn’t claim it’s low fat, practice a little skepticism. If the French can get away with a little steak au poivre, I’m sure you can, too.


A version of this article appeared on page 6 of January 8th, 2013’s print edition of the Nexus.