15 Jul Doesn’t a high fat diet raise my cholesterol?
At Tribal we advocate a Real Food Paleo approach to nutrition, because of this, one of the most common questions I am asked is “how come I can suddenly eat fat?? I thought fat was unhealthy and best avoided??”
The purpose of this article is to outline fat as a key nutrient that is often demonised and overlooked for its health giving properties. If you have any fears regarding symptoms of metabolic or heart disease please consult a medical professional.
Firstly, Lets rewind a little, to understand and explain where the “avoid fat or suffer ill health” belief came from and why it came about.
Then, We’ll go on to identify the fats that heal and should be promoted and the fats that inflame and should be avoided.
Back in 1961, Time Magazine’s cover story named, Medicine: The Fat of the Land, became the public facing vehicle for the work of Ancel Keys, an American Scientist who studied the influence of diet upon health. This was a continuation of the widespread notification of Keys’ work and the-
High saturated fat consumption causes high cholesterol in the blood and causes heart disease.
The hypothesis was developed initially from an intuitive correlation of higher rates of heart disease among American business executives, presumably among the best-fed persons. Keys was heavily criticised for his work so he latterly attempted to add scientific weight to his hypothesis that a low-fat diet is healthy, the results of what later became known as the Seven-Countries Study appeared to show that serum cholesterol was strongly related to coronary heart disease mortality. However, there have been major holes pointed out in this study as Keys’ cherry picked data from countries that supported his hypothesis, leaving out 16 countries in total who’s outcome didn’t support his hypothesis.
Keys was not one to hold back and he was outspoken regarding the North American habit for making the stomach the garbage disposal unit for a long list of harmful foods, clearly an issue for long-term health, with this we cannot argue. One of the key downfalls of the work of Keys, was that Keys’ had hypothesised that the route cause for our issues was animal fat and that vegetable fats where the healthier option. We’ll tackle this great misconception later in this article.
Lipid hypothesis: High cholesterol in the blood causes heart disease.
A study in 1984 showed a correlation between cholesterol lowering drugs and a reduction in heart disease and strengthened the Lipid hypothesis that you see above, in the same year, based on the Diet-Heart Hypothesis (High Saturated Fat causes High Cholesterol) of Keys and this latest study Time Magazine reported that a reduction in bacon, eggs and butter as a means for reducing your risk of heart disease.
They took A. the 1984 study added it to B. The Diet-Heart hypothesis and came up with C. Reducing Saturated fat intake reduces your risk of Heart Disease. None of this summation was ever actually proven. It was also widely accepted that vegetable oils where the better choice and there was an increased move away from the traditional and stable high heat animal fats like butter, lard and suet.
Soon enough, it was a widely accepted household belief that fat was the route cause for our expanding waistlines and increasing metabolic health issues such as obesity, diabetes and coronary heart disease. The “Low-Fat’ craze had hit and the food and big-pharma industries would be taking advantage introducing greater amounts of processed and engineered fats like margarine, vegetable oils and low-fat alternatives.
In 1997, Keys himself stated “There’s no connection whatsoever between the cholesterol in food and cholesterol in the blood. And we’ve known that all along. Cholesterol in the diet doesn’t matter at all unless you happen to be a chicken or a rabbit.”
The chicken and rabbit part of the statement refers to a study where these animals where force-fed high-levels of cholesterol. Since rabbits and chickens are mostly vegetarian, their physiology is not adapted for processing such large amounts of dietary cholesterol, so it’s no surprise they developed atherosclerosis (fatty-plaque deposits and hardening arteries). The mistake was assuming that the results of this experiment could be extrapolated to humans, who are omnivores with significant differences in physiology.
Coming full circle, the 2014, June issue of Time Magazine has the cover story named, Don’t Blame Fat, Bryan Walsh describes the 1980’s move away from fat and promotion of a low-fat diet as a “Vast Nutritional Experiment” and describes the outcome here-
“Nearly four decades, the results are in: Americans cut the fat, but by almost every measure they are sicker than ever. The prevalence of Type 2 diabetes in the U.S. increased 166% from 1980 to 2012. Nearly 1 in 10 American adults has the disease, costing the country’s healthcare system $245 billion a year, and an estimated 86 million people are pre-diabetic.”
The worrying statistics for metabolic disease are not limited to the U.S., the low fat modern western diet is spreading fast across the globe and as the following table suggests, so are the metabolic health issues.
Weight Matters- The increase in obesity prevalence since 1980.
Earlier I alluded to Keys’ recently challenged belief that animal fat is bad and vegetable fat is good and our overall fat intake should be lower, also that elevated cholesterol equals heart disease. To understand why this has been challenged we need to understand what cholesterol is and how different fats affect it. The answers are derived mainly from the Weston A Price Foundation, a key resource for Tribal and inspiration to return to our original natural diets.
Here is an explanation of the essential nutrient cholesterol is from Chris Masterjohn Phd and author for Wise Traditions, the quarterly Weston A Price Foundation journal.
“If you wanna understand what cholesterol does in the body, the best way to look at that is to look at cholesterol deficiency. And cholesterol deficiency can be seen in what’s referred to as Smith-Lemli-Opitz Syndrome, SLOS, this is a genetic deficiency in cholesterol production. So if we look at the type of symptoms of this genetic deficiency in cholesterol, we can start to understand the types of things that cholesterol does.
Firstly, most conceptions with SLOS are spontaneously aborted. So the first thing we can see is that cholesterol is essential to fertility, to carrying on a normal pregnancy, and to basic life and growth of a human being. But in the rare cases where someone actually is born with this disorder, they have all kinds of facial and skeletal abnormalities.
They can have mental retardation, autism, hyperactivity disorders, attention deficit disorders, visual dysfunction, endocrine dysfunction, serious digestive problems, and self-injurious and aggressive behavior. So you can start to see that cholesterol is basically affecting everything in the body.”
So, basically, what does cholesterol do in the body? Chris Masterjohn, explains again-
“Well it’s an essential component of our cell membranes where it helps maintain them the consistency of olive oil, not too fluid, not too stiff.
- It’s very important to the brain, our brain is 2% of our body weight but it contains 25% of our cholesterol.
- When we go to sleep at night our brain makes more cholesterol, that’s part of why sleep is good for us. And cholesterol is the limiting factor for the formation of connections between neurons. So we can learn things and remember things.
- Cholesterol is necessary for the production of all the steroid hormones, those that regulate our blood sugar, our mineral metabolism, and all our sex hormones.
- And it’s necessary for the production of bile acids, which is necessary for digestion.
- And a closely related compound 7-dehydrocholesterol is needed for vitamin D synthesis.
So this is cholesterol.”
So its not as simple as, the lower my cholesterol the better my health?
When you get your lipoproteins tested you’re really looking at something very different. People say there’s good cholesterol and bad cholesterol. But that one cholesterol compound is the one cholesterol that was just described above and that does all of those great things in the body.
There are different types of lipoproteins, but lipoproteins carry cholesterol, they aren’t a type of cholesterol. We have three different kinds of cholesterol carrying lipoproteins-
- High Density Lipoproteins (HDL)- Popularised as good lipoproteins. HDL scavenges the blood and removes excess lipid deposits from the arteries. HDL is elevated by saturated fats.
- Large Buoyant Low Density Lipoproteins (LDL)- These account for 80% of the circulating LDL, it’s increased by saturated fat and the fat promotes greater buoyancy of the lipoprotein. Large Buoyant LDL has a neutral impact and by itself poses little risk for heart disease. (Lustig, 2013), (Kresser, 2013).
- Small Dense Low Density Lipoproteins (LDL)- Conversely, Small Dense LDL, that account for approximately 20% of the lipoproteins, is driven by dietary carbohydrates. It is the sticky Small Dense LDL that contributes to heart disease. (Lustig, 2013)
- Triglycerides– Circulating lipids in the blood are known as triglycerides, these are not cholesterol. High levels of triglycerides are linked to heart health concerns. High levels of triglycerides are caused by overeating and a lack of physical activity, a greater perception of the relationship between carbohydrate, satiation signals, and blood sugar control is needed to control the level of triglycerides in the blood, circulating triglycerides are commonly driven up by a low-fat/high carbohydrate diet that people undertake when dieting or attempting to eat healthily aligned with conventional wisdom.
In the latest, Time Magazine article, Bryan Walsh states-
“There’s a risk that people have been steered in the wrong direction by using LDL cholesterol rather than LDL particle type as the risk factor”.
It is not the amount of cholesterol but the amount of Small Dense LDL particles and heightened circulating triglycerides that are the greatest risks for heart disease.
Essentially the intestines and the liver are secreting these lipoproteins in order to transport cholesterol, fats, and fat soluble vitamins, such as vitamin A, D, E, and K, coenzyme Q-10 and so on, to the many other cells in the body and to make sure that these nutrients are reaching those cells (Masterjohn, 2012). If your aiming for your cholesterol to be as low as possible and not addressing the ratios of your HDL to Circulating Triglycerides or the gross amount of Small Dense LDL you are seriously compromising your health status.
How much fat is healthy?
It’s impossible to answer this question without considering the relationship between all our macronutrients (carbohydrate, fat and protein). Protein generally self regulates as we find it difficult to digest more than we need and ends up totaling around 15%-20% of our total calorie intake.
The ratios between carbohydrate and fat ingestion is where you have some play and it would be Tribal’s recommendation for heath and performance that you periodise your balance between carbohydrates and fats throughout your training year to match your goal, training type and volume.
At times when body composition and health is a priority and activity levels are a little lower; the focus of your training is more on strength and skill development rather than racing, your carbohydrate intake may only make up 25-30% of total energy consumption. I’ll cover carbohydrate choices and the link between carbohydrate, metabolic disease and heart disease in a later article. When carbohydrate ingestion is low, fat intake needs to become higher and may make up as much as 55% of your total calorie ingestion.
The vice versa is also true, when carbohydrate ingestion elevates, % fat ingestion should balance. With increased activity, your total energy consumption needs to elevate, total carbohydrate consumption increases and therefore fat ingestion stays fairly constant. It’s important to understand here that the extreme volumes of exhaustive exercise that bring about this need for increased carbohydrate ingestion are not in line with our genetics, therefore, we should be regularly cycling back to the higher fat approach detailed in the previous paragraph to promote recovery, control of inflammation and health.
Not all fat is the same
The previous recommendations may sound like a lot more fat than you have been used to eating, especially if you have previously been eating a low-fat, high carbohydrate diet in line with the food pyramid.
It is imperative to remember that it’s largely the quality of food and fat that you eat, as much as the quantity that determines health and performance. These guidelines for sources of the different types of fat can be found in more detail in Chris Kresser’s book, The Personal Paleo Code.
Saturated Fats (Long and Medium Chain)
Long Chain Saturated Fats
Solid at room temperature and are mostly from animals, examples are milk and meat from ruminants like cattle and sheep. Saturates form the core structural fats in the human body, comprising 75-80% of fatty acids in most cells and they’re our primary store of energy. In other words, when our body stores excess energy from food for later use, it stores it primarily as long-chain saturated fat.
Unlike polyunsaturated fats and carbohydrates such as glucose and fructose, saturated fats have no known toxicity- even at very high doses- as long as insulin levels are within the normal range.
Long-chain saturates are essential to endurance athletes- they control inflammation and are more easily used as energy than polyunsaturated fats, and the process of converting saturated fat into energy leaves no toxic by-products, only carbon dioxide and water.
Affect of long-chain saturated fats upon key markers for heart health.
- Beneficial to cardiovascular function. Reduces levels of Lp(a), an inflammatory substance in the blood that promotes heart disease.
- Improves lipid profiles by increasing HDL, decreasing circulating triglycerides and raising and promoting large buoyant LDL particles.
Main sources are? Fattier cuts of beef, lamb and pork; cream, whole milk, butter, ghee; smaller amounts found in coconut and egg yolks.
Should I eat these? Absolutely yes, along with monounsaturated fat, saturated fat should comprise the bulk of your fat intake. As I have already mentioned, quality is king here- eating fat from a cow raised in a shed with no sunlight, pumped with growth hormone and fed a diet based on grains- the fat is going to do you no good.
Medium Chain Saturated Fats or Medium Chain Triglycerides
Mainly found in coconut, medium-chain saturated fats have unusual properties. They are metabolized differently from long-chain saturated fats: they require no bile acids for digestion and they pass directly to the liver via the portal vein. This makes medium-chain saturated fats a great source of easily digestible energy and as an endurance athlete; these fats should become part of your fuelling protocol.
In addition to being great for energy they are also anti-bacterial, anti-viral and have antioxidant properties. As they are so immediately usable for energy, they promote thermogenesis or enhanced fat burning that is so vital to endurance sports.
Main sources are? Coconut and its derivatives- flesh, oil, milk and butter and MCT oil.
Should I eat these? Use coconut oil for cooking, it is resistant to the oxidative damage that can occur at high heats with other fats. Also, use MCT oil as part of your fuelling protocol.
Primarily found in olives, avocado, some meat and certain nuts, macadamia’s being my personal favourite. as with saturates, monoumsaturated fats are integral to the formation of our body and are non-toxic even in high-doses. These are the fats that are promoted within a Mediterranean diet, so, nearly all groups agree that these fats are healthy.
Monounsaturated fats increase HDL and reduce LDL, including the small dense variety and triglycerides.
Main sources are? Olives, olive oil, avocado, lard (pork fat), duck, chicken, egg yolk, macadamia nuts, and almonds.
Should I eat these? Eat liberally, but, be aware that some of these foods are also sources of omega-6, as explained below this essential fat can be prevalent and out of balance with omega-3 within the modern diet and in excess can be pro-inflammatory.
Trans Fats (Natural and Artificial)
Artificial trans-fats have slightly different chemical structure to natural trans-fats found in beef and butter. But these minor differences in structure lead to dramatically different effects in the body. Whereas natural trans-fats may reduce the risk of cancer, heart disease, obesity and other inflammatory conditions, artificial trans-fats have been shown to increase the risk of those diseases – even at relatively low doses.
Artificial trans-fats have a negative impact upon cardiovascular health. Pro inflammation, they damage the fragile lining of the blood vessels, increase LDL particles, reduce HDL and block omega 3 conversion. They provide absolutely no beneficial role in human health, yet they cause significant harm.
Main sources are? Processed, refined and fried food (cakes, margarine, fast food, frozen food, crisps, biscuits, crackers, chocolate bars) and packaged foods (instant soups, cake mixes, microwave popcorn, flavored rice and pasta mixes).
Should I eat these? Not if you value your health.
You will be familiar with these essential fatty acids as Omega-3 and Omega-6. Omega-3 fats are present in green leaves and algae (and the animals that eat them) and omega-6 fats are found primarily in seeds (as well as the animals that eat them).
As essential fatty acids, we must, therefore, acquire these from our diet. The optimum ratio of these fats is somewhere close to even, Omega-3:Omega:6 fatty acids as 1:2-1:4. These fats only make up about 4% of our total calorie intake, hence, we only need a little from the sources listed below. The optimum ratio promotes a calm body and controls inflammation.
The modern western diet that is popular amongst developed countries has lost sight of this delicate balance of essential fats and promotes a far higher Omega-6 intake than was ever present in our evolutionary past. The higher consumption of Omega-6 being driven largely by an increase in industrial seed oils- corn, cottonseed, soya, sunflower, safflower and rapeseed. The increased consumption of the above oils has also been met by a radical decrease in the consumption of oily fish, our main source of Omega-3. The ratios commonly reported for people following a modern western diet are closer to 1:20. Ratios like this, are so far from our evolutionary predisposition, are pro-inflammatory and are believed to be a major contributing factor to our increased prevalence of obesity, type-2 diabetes, metabolic syndrome, autoimmune disease and heart health issues.
Main sources are?
Omega-3 Fatty Acids- Found in small quantities in leafy green vegetables, walnuts, eggs and animal meats. The greatest source of Omega-3 fatty acids is oily fish, salmon, mackerel and herring being amongst the best sources.
Omega-6 Fatty Acids- Readily available in nuts, seeds and grain products, meats and industrial seed oils as listed above, please bare in mind that processed foods always contain these oils.
Should I eat these?
We have to make an attempt to re-address this ratio.
Omega-3 Fatty Acids- If you are healthy and free from heart disease, aim to consume at least 2 portions of oily fish each week. If you consider yourself at risk of heart disease, increase your intake of oily fish up to 4 portions per week and follow the guidelines for Omega-6 reduction below.
Omega-6 Fatty Acids- Avoid industrial seed oils and grain products and the foods that contain them completely. Eat poultry, avocado and nuts in moderation, as mentioned above, these are sources of both monounsaturated fats and Omega-6 so its not as clear cut, non toxic as it immediately sounded above.
What really causes heart disease?
It is not saturated fat, or indeed cholesterol that cause heart disease. Rather, it is our movement away from our original diets and lifestyles that have caused the inflammation and oxidative stress that cause metabolic syndrome and heart disease.
Here is a list of the primary risk factors for compromising your cardiovascular health; it’s a wonderful thing that these are all in your control-
- Tobacco use.
- Physical inactivity.
- Poor quality diet, the consumption of non-foods.
- Increased adipose tissue/ obesity.
- High blood pressure.
And, here’s a couple that maybe you hadn’t thought of previously-
- Oral health issues/ gum disease.
- Sleep disturbance.
A Simple Strategy for Fatty Success
Sarah Pope, author of a great book called ‘Get Your Fats Straight’ suggests a really simple 3-Step process for improving the quality of fats you are ingesting.
Replace all your margarines, spreads and liquid vegetable fats with good quality, nutrient dense butter from healthy cows. You can use butter for high-heat cooking, baking, spreading, and, for making your veggies even more delicious. KerryGold pure irish butter is a great option, its from grass fed cows.
Begin supplementing with fermented cod liver oil. You’ll increase your intake of fat-soluble vitamins- A, D and K and essential fats, omega -3.
Start consuming coconut oil. You can use this medium chain saturate for high-heat cooking, take as a supplement by the spoonful or add to a smoothie. Additionally, make a point of beginning to use MCT oil as a supplement around your training- as a derivative of coconut oil it maintains the health benefits but can easily be added to coffee, tea, soups, salad dressings or your chosen training fuel to improve blood sugar regulation, appetite regulation and concentration. Avoid cooking at high heats with MCT and start slowly, one teaspoon a day and increase to as much as three tablespoons, introducing too quickly may cause digestive discomfort or disturbance, ensure you monitor your reaction before increasing.