Of all the differences with my "real food lifestyle," fat is by far the most misunderstood. After a comment from a reader here; my sister asking, "Butter is only good in moderation, right?;" and conversations with friends about "fattening" food; I decided a post detailing fats was in order. I am going to do this in a book report. All of this information comes from Nourishing Traditions by Sally Fallon in the Introduction section on Fats.
Fats provide energy, are used for building cell walls and hormones, and slow nutrient absorption (so we can go longer between meals). They allow our body to use fat soluble vitamins and absorb some minerals.
Saturated fats make up more than half of cell membranes. Saturated fats keep our bones healthy by allowing calcium to be incorporated. They lower Lp(a), defined as "a substance in the blood that indicates proneness to heart disease." They protect the liver from toxins. They build the immune system. We need them to use omega 3 fatty acids. The fat around our heart is highly saturated. Saturated fats protect us against harmful microorganisms in the digestive tract.
We have been taught that fat and cholesterol are harmful to our bodies. This theory, by Ancel Keyes, is called the Lipid Hypothesis. (Note that it is a hypothesis, but taught widely as fact.) There were many flaws in his research, but his theory received more publicity than opposing views, partly due to backing by the vegetable oil and food processing industries. Fallon says, "Most people would be surprised to learn that there is, in fact, very little evidence to support the contention that a diet low in cholesterol and saturated fat actually reduces death from heart disease or in any way increases one's life span."
She then sites the following studies:
*In 1920, heart disease was rare. In the mid 1950's, heart disease was the leading cause of death in the U.S. Today it causes at least 40% of all deaths in this country. If what we have been taught is true, and saturated fats cause heart disease, then "one would expect to find a corresponding increase in animal fat in the American diet." But that's not what happened: saturated fat consumption decreased from 83% in 1910, to 62% in 1970. Butter went from 18 pounds per person each year to only 4. In this same time frame, vegetable oils increased 400% and sugar and processed food went up 60%.
* The Framingham Heart Study, which took place in Framingham, Massachucetts, collected data from 6000 people every 5 years starting in 1948. There were two groups: one who consumed small amounts of fat and cholesterol, and another who ate large amounts. After 40 years of this experiment, the director said, "In Framingham, Mass., the more saturated fat one ate, the more cholesterol one ate, the lower the person's serum cholesterol... We found that the people who ate the most cholesterol, ate the most saturated fat, ate the most calories, weighed the least and were the most physically active."
*A British study of several thousand men divided the men into two groups. The men on the strict diet reduced their saturated fat and cholesterol, stopped smoking and increased consumption of unsaturated oils. The other half continued on as they had, with no reduction in saturated fat or cholesterol, and were even permitted to continue smoking. After a year, the men on the strict diet had 100% more deaths than those who did not change their behaviors.
*MRFIT (Multiple Risk Intervention Trial) was a study comparing the death rates and eating habits of more than 12,000 men. The men who reduced saturated fat, cholesterol and smoking had a marginal decrease in coronary heart disease, BUT their mortality rate was higher. There was an increase in deaths from cancer, brain hemorrhage, suicide and violent death. Other studies have had similar results.
* The LRC-CPPT (Lipid Research Clinics Coronary Primary Prevention Trial) gave all subjects a low fat, low cholesterol diet and cholesterol lowering drug or placebo. The subjects given the drug had a 24% decrease in heart disease related death, but other causes of death increased (cancer, stroke, violence and suicide). This study is often cited to give proof in favor of low fat diets, though low fat diets were not tested at all in this study (only the cholesterol lowering drug was).
*Michael DeBakey conducted a survey of 1700 patients and found no correlation between cholesterol in the blood and hardening of the arteries. A survey of South Carolina adults had similar results.
*Mothers milk is high in cholesterol and fat. Over 50% of calories in breast milk come from fat.
*Traditionally, people used animal fats.
Yemenites in Yemen: eat fats of animal origin. Yemenites living in Israel used vegetable fats (and large amounts of sugar). There was little heart disease or diabetes with the Yemenites in Yemen, but large amounts of both with the Yemenites in Israel.
India: People in Northern India eat 17 times more animal fat but have a 7 times lower rate of heart disease than people in Southern India.
Masai in Africa: eat mainly blood, milk and beef and have no heart disease and low cholesterol levels.
Eskimos: Eat lots of animal fats and have little or no heart disease on their native diet.
China: A study found that those in areas where whole milk was consumed in large amounts had half the rate of heart disease as those where only small amounts of animal products were consumed.
Mediterranean: Fat (including saturated fat from lamb, sausage and goat cheese) equals up to 70% of their calories. They are known for their low rates of heart disease.
Puerto Rico: The Puerto Ricans
Soviet Georgia: Those who ate the most fatty meat lived the longest.
Okinawa: The average life span for women is 84 years. They eat pork, seafood, and cook their food in lard.
If you had come up to me 10 years ago and told me that I would be blogging in favor of fats today, I think I would have said "Yeah, right" (and also, "what's blogging?"). Everything I'd ever read in magazines, fitness publications (I used to teach aerobics), nutrition/ diet books, and saw on the news said that fat is BAD. But the more I read about the actual studies that have been done, the more I realize, there was little reason to ever think that. Fat is not only necessary for our bodies and health, it is essential. And yes, saturated fat, I mean you.
I'd love to hear about any studies that helped convinced you that fat was not an evil villain, and how you got over your fat phobias. Please share!
This post is part of Fight Back Fridays.
This post is part of Fight Back Fridays.