This post is the second in a series on why fat – even saturated fat – is good for us. I’ve shared my personal experience with low fat dieting, and today we’ll take a look at what the science actually says is true about fats and our health.
I hope the Making Friends with Fat series is helpful to you. I’d love to hear your story, too, whether it’s similar to or very different from my own. Please leave comments as we go along so I can address particular concerns and questions you may have about this complex, but very important topic! And, of course, please share this series with others who might find it helpful!
Earlier this week, in Part 1 of the Making Friends with Fat series, I shared the story of how buying into the low fat farce as a teenager cost me dearly. Over the past 15 years, the Lord has brought great spiritual healing from my once destructive thoughts and behaviors; but some of the physical consequences of starving my body of fat and other critical nutrients still linger.
At times I wish I could undo the damage I did to my body all those years ago. But I’m also grateful for the journey of learning and healing that has now come from that difficult season of my life. I only hope that, by sharing this with others, some may benefit and not have to repeat my mistakes.
So without further ado, let’s chew the fat! (I couldn’t resist that one)
What We’ve Been Told About Fat Isn’t All True
For years, the medical literature and nutrition guidelines of every major health organization have steered us away from animal fats, instead encouraging replacement with vegetable fats that were apparently heart healthier.
The problem is, much of the supporting science was faulty. Here’s what the research actually says about common “truths” about fat, cholesterol, and heart disease:
“Low Fat Diets Protect From Heart Disease”
The most widely cited research in favor of low fat diets was published by Dr. Ancel Keys in the 1950’s. Unfortunately, his “Six Countries Study” (later reevaluated and renamed the “Seven Countries Study”) omitted data from 16 additional countries that would have negated his findings entirely. The unreported data from those 16 countries included some with low fat diets and high incidence of heart disease, as well as others with high fat diets and low incidence of heart disease (Source).
Years later, in 1977, the McGovern Committee in the US Senate published the first set of Dietary Goals for all Americans in which we were encouraged to eat less fat and more whole grains. This advice lacked scientific support and was questioned by many scientists and even the American Medical Association (Source). Rebuttals were silenced, Big Ag increased production of commodity grains like wheat and corn, and heart disease took it’s place as the #1 killer of Americans. Thanks, Senators.
“Saturated Fat Intake Raises Heart Disease Risk”
If total fat intake isn’t to blame, then maybe a specific type of fat – like saturated fat – is?
There are three common faults of studies linking saturated fat to heart disease: (1) Inaccurate collection methods for food intake data; (2) Saturated fats were often replaced with inflammatory polyunsaturated fats (e.g., refined vegetable oils) or refined carbohydrates, both of which are now believed by many to play key roles in the development of heart disease; and (3) The follow up was only short-term.
When only longer term human studies with proper data collection methods are evaluated, and when factors such as age, gender, polyunsaturated fat and trans fat intake are properly accounted for, there is no significant relationship between saturated fat and cholesterol, or saturated fat and heart disease risk. (Sources 1, 2, 3)
In 2014, a very large meta-analysis of 76 studies evaluating the link between various dietary fats and heart disease was published in The Annals of Internal Medicine. The conclusion of the meta analysis was that “Current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of total saturated fats.” (Source)
Furthermore, this chart compiled by Dr. Mercola, shows the very high saturated fat content of tribal diets around the world – not coincidentally, these tribes all have very low rates death from heart disease (Source):
|Tribe||Primary Diet||Percentage Saturated Fat|
|Maasai tribe in Kenya/Tanzania||Meat, milk, cattle blood||66 percent|
|Inuit Eskimos in the Arctic||Whale meat and blubber||75 percent|
|Rendille tribe in NE Kenya||Camel milk, meat, blood||63 percent|
|Tokealu, atoll islands in New Zealand territory||Fish and coconuts||60 percent|
“High Cholesterol Levels Raise Heart Disease Risk”
In the early 2000’s, a government committee – the National Cholesterol Education Panel (NCEP) – made this conclusion and issued target cholesterol levels for healthy Americans. A 2006 review of the evidence on which the committee’s target levels were based revealed very weak support and, in fact, called for a re-evaluation of the numbers (Source). Eight years later, the cholesterol targets are unchanged.
Of note, 8 of the 9 NCEP members were on the payroll of pharmaceutical companies that produce lipid-lowering statin drugs at the time the recommendations were issued (Source). Hmmm….
What Is True About Fats
So what should we believe about fats? I’m glad you asked…
Saturated Fats are Healthy
Until the 1900’s people consumed large amounts of saturated fat and rarely died from heart disease.
Saturated fats give structure to cell membranes. (Source)
Saturated fats aid immune function. (Source)
Saturated fats improve gut health. (Source)
Saturated fats assist in calcium deposition into bones. Dr. Mary Enig – considered an expert on fats – recommends a whopping 50% of fat intake should be saturated for optimal bone health. (Source)
Cholesterol is Healthy
Cholesterol is needed to form every cell membrane in the human body. If that’s not a significant and healthy role, I don’t know what is!
Cholesterol is needed to produce bile, which helps digest fats and fat soluble vitamins A, D, E, and K. (Source)
Cholesterol aids in the conversion of vitamin D to it’s active form within the body (did you know that most vitamin D requires conversion to be beneficial?) (Source)
Cholesterol is required for hormone production (including estrogen, testosterone, cortisol, and others). (Source)
Cholesterol aids in the brain’s use of serotonin (a “feel good chemical”). Low cholesterol levels have been linked to aggressive and violent behavior, depression and suicidal tendencies (Source)
For women in particular, those with higher cholesterol live longer. Yes, you read that right! (Source)
Eating Healthy Fats Can Help You Lose Weight
There are a few reasons this is true. One is simply that fats are very satisfying. My personal experience has been that eating more fat, particularly when paired with lower carbohydrate intake, smaller amounts of food are satisfying to me, and I don’t find myself craving snacks between meals as often either.
Secondly, when adequate amounts of fat – namely saturated fat and cholesterol – are consumed, the body is better able to manage hormones like insulin, thyroid hormone, estrogen, testosterone, and others that are vital for weight management. (Source)
Fat Soluble Vitamins A, D, E, & K are Most Concentrated in Animal Fats
Despite research that has tried to parse out one or the other of these vitamins, they work best in combination with one another, and serve as antioxidants, immune boosters, and play important roles in formation of teeth and bones. A, D, E, and K are most abundant and best absorbed from animal foods such as butter, tallow, lard and liver. (Source)
Most People Should Increase Omega-3 Fats & decrease Omega-6 Polyunsaturated Fats
Both omega-3 and omega-6 fats are polyunsaturated, but most Westerners consume too little omega-3 and far too much omega-6, especially in the form of cheap and highly processed vegetable oils. The ideal ratio of omega-6:omega-3 is around 2:1; but estimates of the standard American range from as little 14:1 to as much as 25:1, which results in inflammation and a host of health problems (Source).
Decrease intake of these:
Increase intake of these:
Wild caught, fatty fish
Trans Fats and Interesterified Fats Should Be Avoided
In all the controversy regarding fats, one thing seems to be agreed upon by all parties – artificial trans and interesterified fats (from “hydrogenated” and “partially hydrogenated” oils) are harmful in a number of ways and should be avoided entirely.
To be sure you’re not consuming these, look at the ingredient list rather than the nutrition facts panel. By law, a product can be labeled as having “zero” trans fat even if it contains up to 0.5 grams per serving. Hopefully this will change with the implementation of the FDAs plans to ban trans fat in the US food supply. This may not sound like much, but studies indicate increased risks of infertility, heart disease, stroke, diabetes and more with even minimal daily intake of trans fats (Sources 1, 2, 3)
A Back To The Book Summary of Fats
As a dietitian, I enjoy sorting through the literature to learn what (good) science proves is healthy.
But, more importantly, as a Christian, I love that the bottom line on fats and health is basically this:
If God made it, it’s good for us.
Read other posts in the Making Friends with Fat series!
I’d love to hear your thoughts & questions about dietary fats and our health.
Leave a comment below to get the conversation started!