Ok, first a great big "thanks" to all those who have read my last blog post and left kind comments - I hope you all found it interesting and eye opening!
It's great to hear that I am reaching people - that was always my hope and my intention.
I can think of a number of people that, as a direct result of my last post (and some of the videos) are now in the process of changing the way they eat and shouting about it to their friends. Fantastic! Keep spreading the word.
If you haven't read it yet - no worries, you are here now, so maybe just read my last post before dipping into this one. Also, if you haven't watched "The Big Fat Fiasco" vids (linked in the post) then please do - they are essential viewing!
So, I spoke about food groups, in general, during my last post - but I think it might be worth delving a little deeper and talking about one specific food group in our diets and one that continues to get grossly misrepresented.
More specifically, saturated fats and more specifically still, cholesterol...
So here goes...
In my last post, I spoke about the different types of food we consume to fuel our bodies during work, rest, day to day activities and sports type activity.
I also called into question the validity and health benefits of the "Low fat / High Carb" diet that we have been brainwashed into believing for several decades!
We have a number of people to thank for this myth but a certain biochemist called Ancel Keys probably sits at the top of the tree.
It was his studies in the 1950's along with a great big dollop of bad science that lead to the so called "Lipid Hypothesis" which in essence was... if you eat fats, you get fat and the associated levels of fat and cholesterol in the blood will increase your risk of Atherosclerosis (ASVD) and coronary heart disease (CHD). So don't eat fats (particularly saturated fats), eat grains and vegetable oils instead.
Tom Naughton provides a great analogy in his film "Fat Head" - a brilliant and funny movie well worth a watch.
He asks that we imagine the whole of human history (over 1 million years!) compressed into 1 year. He states that, proportionally, we have only been farming and eating grains since yesterday (when we started becoming shorter and fatter) and we started consuming processed vegetable oils about 10 minutes ago (when heart disease became our number one killer). So after examining all this human history the "experts" (Ancel Keys among them) suggested that we all start eating what?
Yup - more grains and processed vegetable oils!!
That's right, in order to protect our heath, it was suggested that we should all eat more of the foods that we hadn't eaten for 99% of all human existence!!
Sorry.. did I miss something??
Thankfully the whistle has been blown on this hypocrisy, it's bad science exposed and the general population gradually coming round to the idea that they may have been sold a pup.
But elements of this myth still remain and a biggy is Cholesterol.
We've all heard of Cholesterol and how bad for us it is. We all know how increased Cholesterol levels can increase Atherosclerosis (ASVD), Coronary Heart Disease (CHD) and heart attack risk and we know that these increased levels are, by and large, due to consuming cholesterol rich foods like saturated fats and dairy right? Right?
Again we have our friend Ancel to thank for this one following his now famous study (that got him the cover of Time magazine) were he showed a "link" between high blood cholesterol levels in different countries and increased incidence of CHD.
What he actually showed was an "association" or "correlation" and, as any good scientist knows, correlation does not imply causation. In fact, as we will see later, Ancel didn't even see an association, but he "manipulated" the data to show one.
A great example that illustrates the inherent weakness of "observational" studies is shown in the Fat Fiasco video. It sites one such study which showed that women who were taking oestrogen (HRT) were "seen" to have a lower than average incidence of CHD, leading doctors to propose that HRT was protective against CHD. However, further "clinical" trials actually showed that HRT caused a small but statistically significant increase in risk of CHD. How could this be?
Re-analysis of the data from the observational studies showed that women undertaking HRT were more likely to be from higher socio-economic groups, with better than average diet and exercise regimes and generally more likely to look after themselves. The use of HRT and decreased incidence of coronary heart disease were coincident effects of a common cause (i.e. the benefits associated with a higher socio-economic status), rather than cause and effect as had been supposed.
So back to Ancel and his bad science. Another crafty trick he pulled was to disregard any findings that didn't suit his own hypothesis, so Aboriginal Australians were dropped from the study because they had very low levels of cholesterol but some of the highest incidence of CHD in the world. Conversely the Swiss, very high cholesterol, very low incidence of CHD. So the Swiss result was not included! These are just two examples of many nations that did not follow the link Ancel was trying to prove.
Looking at all the data - it's impossible to make any connection between blood cholesterol and CHD....
Supported by equally flawed observational analysis like the Framingham Study, the myth refuses to die....
Lets try and put this one to bed...
Firstly, some stuff you maybe didn't know about cholesterol...
Cholesterol is a very important chemical in the human body.
Cholesterol is actually a "Steroid Metabolite" and is an essential structural component of every cell of our bodies - without it our cells would literally fall apart and we'd be a pretty unpleasant blob on the floor.
Cholesterol is a potent antioxidant and a "metabolic nutrient" able to heal the body from infection and repair damaged tissue.
It helps synthesise vitamin A, D and K and without it our bodies can't produce bile or bile acids needed to digest protein.
So cholesterol is a good guy ok!
Ahhh but what about "bad" cholesterol I hear you say!
Well lets get this straight....there is no such thing as "bad" cholesterol or "good" cholesterol for that matter. Just cholesterol.
So maybe some of you have heard of HDL and LDL cholesterol. I'm not surprised, we hear these terms banded about all the time on the TV by the likes of Gloria Hunniford intent on selling some magical margarine designed to stop us all from dropping dead from heart failure.
What Gloria doesn't know is that HDL cholesterol and LDL cholesterol aren't even cholesterol! They are proteins (High density lipoproteins and Low density lipoproteins).
Cholesterol is a waxy chemical that is not soluble in the watery environment of blood so it needs to be transported within certain protein molecules around the body. That's where HDL and LDL come in.
So why is HDL (wrongly) touted as "Good" and LDL considered "Bad"
LDL is simply transporting cholesterol FROM the liver TO the body tissues. If you believe (incorrectly) that cholesterol is bad, then I suppose anything that transports it TO the body tissues must also be considered "bad".
This is completely and utterly wrong! Wrong wrong-idy wrong...
LDL is simply transporting cholesterol to where it needs to be in the body. LDL is just trying to help by carrying cholesterol it to where it can mop up cellular damage, repair cells and make new ones. So stop picking on it ok!
HDL on the other hand gets all the brownie points for transporting this "poison" away from the tissues. (If I were HDL, I'd spend all my time blowing raspberries at LDL - but that's just me) So where does HDL take this cholesterol? You'd assume, because cholesterol is so "bad" and HDL is so "good", it would transport it out of the body ASAP wouldn't you.
But it doesn't
It actually takes it to the liver - where it is recycled and re-used. Our bodies know how important cholesterol is. It a complex chemical compound that the body wants to hang on to. It's far easier to recycle than it is to re-manufacture.
A great quote from Natasha Campbell McBride, MD goes something like this...
Calling HDL "good cholesterol" and LDL "bad cholesterol" is like calling an ambulance en route to an patient a "bad ambulance" and an ambulance en route to the hospital a "good ambulance".
If we are to listen to the experts, we are expected to believe that the liver is actually manufacturing, using, recycling and re-using a compound, within the body, who's sole purpose is to give us a heart attack! Seems unlikely to me...
In relation to cholesterol, there are however a few parameters that do matter.
There is good evidence to suggest that the ratio of LDL to HDL is important. Not the actual numbers that you hear quoted by some doctors and dietitians, but the ratio.
With this fact in mind, lets look at something like butter. Yup, good old tasty, natural, saturated fat, butter. Yes it raises LDL cholesterol, but it raises HDL cholesterol as well. So the effect on our bodies is, at worst completely neutral (except for all the positive nutritional effect of course). One might even be so bold as to suggest butter could reduce coronary heart disease risk. But increase? Nope, sorry, it just doesn't. The same for all natural fats that man has chosen to leave well enough alone!
The other factor that is extremely important is molecular size.
"Small, dense, LDL" are the real bad guys. These proteins can pass more easily into the arterial wall, where they can build up to form fatty plaque deposits. Normal LDL then joins the party in an effort to mop up the rancid, oxidised proteins and a type of scar tissue forms causing an obstruction of the blood vessel and all of the consequences thereafter. This is most probably where LDL gets its bad rep - but it's just trying to do it's job.
Conversely, large fluffy LDL (as it should be) - causes no such problems. Their particle size means everything keeps flowing as nature intended and cholesterol can go about it's business of keeping us alive!
Ok, so small, dense LDL are the bad guys - but what causes it??
Well, as with most things, you can blame your parents as there is a genetic pre-disposition to have small dense LDL. An active lifestyle will reduce the risk - good news for us athletes!
But diet has a BIG effect and hopefully you can all predict where this is going.....
It's not a diet high in saturated fats that causes small, dense LDL but......
You guessed it....
It's not a diet high in saturated fats that causes small, dense LDL but......
You guessed it....
A diet which is high in refined (high GI) carbohydrates and high in Trans Fats (fats that man has meddled with)!
Is that the sound of a penny dropping?
I hope so!
So what can we learn?
Cholesterol is good - our bodies need it to function, repair and survive.
There is nothing wrong with "Natural" saturated fats. Butter, cheese, eggs, whole milk and yoghurt is all good!
A great "Universal" fat is coconut oil - I may do a mini blog post about this incredible food later - but, suffice it to say, it's now the only fat (along with butter) that I have in my house. I use it for everything from frying, baking, bread making to spreading on toast.
If you must use a vegetable oil - make it virgin olive oil.
The real bad guys are not natural saturated fats but refined, high GI carbs, hydrogenated vegetable oils and trans fats. These can cause an increase in small, dense LDL - which are the REAL precursor to Atherosclerosis and CHD - avoid them and ANY foods containing them!
So there we have it.
Myth busted...pass the butter!