A hundred years ago less than one in one hundred Americans were obese and coronary heart disease was unknown. Pneumonia, diarrhea and enteritis, and tuberculosis were the most common causes of death. Now, a century later, the two most common causes of death are coronary heart disease and cancer, which account for 75 percent of all deaths in this country. There were 500 cardiologists practicing in the U.S. in 1950. There are 30,000 of them now – a 60-fold increase for a population that has only doubled since 1950.
In 1911, Procter and Gamble started marketing Crisco as a new kind of food. The name Crisco is derived from CRYStalized Cottonseed Oil. It was the first commercially marketed trans fat. Crisco was used to make candles and soap, but with electrification causing a decline in candle sales, Procter and Gamble decided to promote this new type of fat as an all-vegetable-derived shortening, which the company marketed as a "healthier alternative to cooking with animal fats." At the time Americans cooked and baked food with lard (pork fat), tallow (beef and lamb fat), and butter. Procter and Gamble published a free cookbook with 615 recipes, from pound cake to lobster bisque, all of which required Crisco. The company succeeded in demonizing lard, and during the 20th century Crisco and other trans fat vegetable oils gradually replaced saturated animal fats and tropical oils in the American diet.
In 1953 Ancel Keys, the father of K-rations for the military, published a study that correlated deaths from heart disease with the percentage of calories from fat in the diet. He found that fat consumption was associated with an increased rate of death from heart disease in the six countries that he studied.
U.S. Dietary Fat: Animal and Vegetable Sources 1909 and 1985
Over the past century, butter consumption has plummeted from 18 grams per person per day to 5 grams. Consumption of lard has dropped substantially while use of shortening has almost tripled. In 1909, shortening was a natural product made with coconut oil and lard. Shortening used today is made out of partially hydrogenated vegetable oil.
Consumption of margarine made with trans fats has gone up five fold, and vegetable oils, more than fifteen-fold. Along with trans fats, these often rancid vegetable oils are new to the human diet.
A good case can be made that these changes in fat-and-oil consumption over the last hundred years are the major cause of the epidemic of obesity, diabetes, heart disease, stroke, cancer, and learning disabilities in children. Observing the increasing use of vegetable oils during the 1940s and 1950s, a few physicians, notably Dr. Weston A. Price and Dr. Francis Pottenger, predicted that there would be increasing rates of such diseases.
Prevalence of Obesity among US adults 1950-2010
An epidemic of obesity has accompanied the adoption of a low-fat diet. With only 1 in 150 people obese when the century began, by 1950 nearly 10 percent of Americans were obese. Thirty years later, in 1980, it had risen to 15 percent. Then following publication of the U.S. Dietary Guidelines and its every-five-year updates, obesity in Americans has steadily risen. Now two-thirds of the American public is overweight, with more than one-third, obese. Today the average American weighs 30 pounds more that he or she did 100 years ago. American women weigh and average 167 pounds and men, 191 pounds.
There is solid evidence that this epidemic of obesity has resulted from replacing saturated fat in the American diet with carbohydrates and processed polyunsaturated vegetable oils.
A review of eating habits in the United States in 2004 found that about 3/4 of restaurant meals were from fast-food restaurants, whereas only 1% were fine food dining restaurants. Nearly half of the meals ordered from a menu were hamburger, French fries, or poultry — and about one third of orders included a carbonated beverage drink. From 1970 to 2008, the per capita consumption of calories increased by nearly one-quarter in the United States and about 10% of all calories were from high-fructose corn syrup.