Is Low Fat Making You Fat?

For decades in America, dietary fats have been demonized. Conventional wisdom from everyone from the American Heart Association to the American Medical Association has given us the message that dietary saturated fat is bad for you, and fat makes you fat.

In the late 1970s and early 1980s high carbohydrate, low fat diets became a matter of public policy. The United States government, via the U.S. Department of Agriculture and the U.S. Department of Health and Human Services, recommended that we eat less fat (and, consequently, more carbohydrates) to lower our blood cholesterol levels.

At about the same time, the U.S. food industry took a radical turn. Foods naturally high in saturated fats and cholesterol underwent processing to “clean” them of these offending substances. Highly processed nutrition bars, cookies and cereals, even bottled water boasted “Low Fat” and “No Cholesterol”.  The new dietary recommendations were a bonanza for the processed foods industry.  Highly processed low fat products, even non-fat cakes and sweets, overflowed store shelves, while natural, nutrient laden full fat products like real butter, full fat milk, fatty meats and cheeses were all but abandoned. These were replaced by products such as non-fat and low fat meats, “butter flavored” margarines and non-fat and low-fat cheese products. Lists of ingredients grew long with hard to pronounce chemicals.  Grains became a staple of the American diet.  With a sense of duty and the confidence that we were doing great things for our health, we ate these new products, despite the fact that they are often flat, flavorless and completely foreign to anything Mother Nature intended.

But as decades passed and we ate more of the new, “healthy", low fat "foods", Americans grew fatter and fatter. Our population, which started at less than 10 percent obesity in 1985, burgeoned upward to greater than 30 percent obesity today, with another 30 percent overweight. For the first time in the history of the world, being overweight or obese in the United States is the norm. Fatty liver disease is now common to persons who were never alcoholics. Obesity-related illnesses like diabetes, fatty liver disease and heart disease are increasingly commonplace, even among children and adolescents. 

What happened to the so-called healthy low fat, low cholesterol diet revolution? Wasn’t it supposed to make us all more healthy rather than less?

Experts suspect dietary policies meant to contribute to health inadvertently made us ill. Researchers at Albert Einstein College of Medicine wrote, “The hypothesis that dietary fat admonitions actually caused the current US obesity epidemic is consistent with the data, logically sound, and plausible on the basis of both behavioral and biological mechanisms.”

In other words, our low fat, low cholesterol diets made us fat and sick.

But doesn’t eating fat make you fat?

The emerging science is intriguing.  A study of nearly 20,000 Swedish women found those who reported eating full fat dairy products gained 15-30 percent less weight than those who didn’t.  And, contrary to predictions made by researchers studying 12,000 children and adolescents, skim and 1 percent milk was associated with weight gain, but full fat milk was not. 

A study of animals gives us clues to how this works. In a study of mice, dietary fats were shown to signal the liver to initiate burning of abdominal (belly) fat. Natural fats also have the ability to signal satisfaction (satiety with a meal), which helps diners curb calories.  If you eat a meal containing natural fats only until you are satisfied with your meal, you are unlikely to gain weight; if you are overweight, you are most likely to shed extra pounds.

What about cholesterol?  Won't I get a heart attack?

Data from the World Health Organization's MONICA study, which looked at heart attack risk factors across  41 population groups in 22 countries found no relationship between death from heart disease and blood cholesterol levels, none at all!  In fact, eggs and other foods rich in natural cholesterols are good for you.

I hear saturated fat is deadly--is that true?

Studies do not confirm a link between natural (not man-made) saturated fat and heart disease, or any common chronic disease for that matter.  There is an association between processed meats, with coloring, additives and preservatives, and chronic illness such as diabetes and heart disease.  So eat butter and bacon if you like, but look for organic sources sans chemical additives.

So, should you cut out highly-processed, lower fat foods? From a health and weight standpoint, it’s a good idea. All of the new and intriguing evidence about natural dietary fats suggests that Mother Nature knows best.


If you do not see a working hyperlink below, just copy the web address and paste it in the address bar of your browser to access the information:

To see how obese America grew over recent decades, take a look at the United States Centers for Disease Control maps at:

To learn more about how lowering carbohydrates in your diet can safeguard your health and weight, visit the Metabolism Society at:

Study fails to link saturated fat and coronary heart disease

Cholesterol and Heart Disease: Data from the MONICA Study demonstrates no link between total blood cholesterol and heart disease

Processed meat, not red meat per se, linked to coronary heart disease (CHD) and diabetes.