The Demonisation of Fat and Cholesterol

Post two ... The Demonisation of Fat and Cholesterol

Before I begin, I don't think this post will actually conclude anything, but is likely to be the start of a load of topics I need to explore further. As I said, these blogs are to help organise my thoughts.

Fat

Fat has had a bad press for as long as I can remember; it still seems to get bad press too, especially from respectable organisations like the British Heart Foundation (fats explained) and the British Diabetic Association (fat facts) who went on air recently (Lucy Jones - Eat Well For Less - BBC) and stated that saturated fats were a big cause of heart disease. But she also said eating plenty of cheap white bread is good for you and doesn't make you feel bloated. Now I know what the "ORLY" internet acronym is for.

I'm not sure how the "Low Fat = Good" thing got started and I can't find an reliable references to cite on this, but there seems to be a mounting body of evidence (excuse the pun!) that this is complete tosh at best and very harmful at worst. When it comes to fats, the only one thing everyone seems to agree on is that trans fats are bad bad bad.

Where possible I'm going to cite pucker peer reviewed studies and not just random internet quackery. Unfortunately, whoever thinks up the titles for the reports of these studies obviously has no flair for the dramatic.

Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease

Conclusions: A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat.

No surprise that there is a Wiki page that follows the controversy of the whole Saturated Fat and CVD /CHD debate. If the researchers and experts can't agree, how are we supposed to make our own minds up?

The NHS isn't much help on this front either as the best it can manage is along the lines of "there seems to be some evidence saturated fat isn't bad but we'll stick with our original advice".

Ok, so I'm still none the wiser; time to look at this from a different angle as it seems every article one way or the other is debunked by another saying the exact opposite.

Cholesterol

So, the big reason not to eat saturated fat is because it causes high cholesterol which is apparently the thing that causes all the nasties.

On this point the NHS looks to have actually got off the fence and said that Saturated fat link with heart disease questioned. Good grief, I can't take the drama. Does HTML have <sarcasm> tags?

It's actually one of the better articles I've read on Dr Malhotra's research, as it's reasonably balanced, quoting ...

Dr Malhotra disputes the idea that this proves a direct cause and effect between cholesterol levels and heart disease: "correlation is not causation", he writes. 

The article points out that saturated fat is believed to raise levels of low density lipoprotein (LDL) cholesterol (so-called "bad" cholesterol), which in turn raises cardiovascular risk. 

Yet only one type of LDL cholesterol seems to be associated with saturated fat intake, the article says. This type of cholesterol is called large buoyant (type A) LDL particles. 

The second type of LDL cholesterol – the small, dense (type B) particles associated with carbohydrate intake – is linked to cardiovascular disease.

So, not all cholesterol is bad and in fact only the type of cholesterol associated with carbs is linked to CVD? Did any of the studies that looked at saturated fat intake also correlate carb intake too? No idea, I can't find any information on this at all. <more reading to do>

The paper says one reason for this rise in obesity is that food tastes worse without fat, so the food industry compensated by replacing saturated fat with added sugar. 

Scientific evidence is now mounting that sugar is a possible independent risk factor for a condition called metabolic syndrome, a combination of diabetes, high blood pressure, obesity and high levels of "bad" fats, such as triglycerides and LDL cholesterol. Metabolic syndrome puts people at greater risk of heart disease, stroke and other conditions affecting the blood vessels. 

Two-thirds of people admitted to hospital with a diagnosis of heart attack have metabolic syndrome, but 75% of these patients have completely normal total cholesterol concentrations, says the paper. "Maybe this is because total cholesterol isn't really the problem," the article suggests.

To depart completely but briefly from the scientific to the anecdotal, I've recently cut out wheat from my diet. At the same time as the Hodgkin's kicked off last time, it had also sparked psoriatic arthritis. After doing a bit of reading I thought I'd try cutting out wheat and since then my joints have been a whole load better. I've not done any dieting other than cut out wheat and still eat like a horse but still I've lost 10kg of body fat ... or ... triglycerides (it was slow, steady loss, so I'm not worried).

I'm not sure if the weight loss is the carbs associated with the wheat, or the sugar that normally goes with the wheat, or something else that I've not thought of. I've also stopped feeling tired during the day, especially after lunch when I used to get an attack of the sleepies; an all round result then.

So, back to the story ...

Cholesterol is bad. What exactly does cholesterol do? (yes, this isn't exactly an academic body link, but it's nice and simple. like me!)

The True Function of Cholesterol in the Body

Here are just some of the many tasks cholesterol accomplishes in your body each day:

- Cholesterol is a crucial building material in the body. It helps maintain the structure of cells and vessels, improving overall health and function in the body.

- Cholesterol is a precursor to important sex hormones like testosterone, estrogen, androgen and progesterone. It is also a precursor to corticosteroids, hormones whose primary function is to protect the body against stress and disease. This includes the crucial hormones, cortisol and DHEA.

- Used as an insulator around nerves, cholesterol promotes healthy nervous system function and helps to prevent diseases associated with the nervous system. It is absolutely essential for brain function.

- Since bile salts are made from cholesterol, adequate cholesterol is needed for proper digestion. In addition, cholesterol aids the digestive system by strengthening the intestinal walls.

- Cholesterol is a precursor to vitamin D, an important nutrient which supports a healthy immune and nervous system, reproduction, insulin production and the metabolism of minerals. Recently the suggested daily allowance for vitamin D has been significantly raised in light of how important it is for good health.

- Serotonin receptors in the brain require cholesterol in order to function properly. Serotonin is an important neurotransmitter that promotes a natural feeling of well-being. Low levels of serotonin are linked to depression, violence and suicide.

I knew they'd get sex in there somewhere.

So, basically cholesterol is good and important; very important. Note to self: another load of reading to do on Statins - another day.

I seem to be going around in circles. Saturated fat is bad, but it's not, in fact it's beneficial. Cholesterol is evil, but it's not, in fact it's essential. Sugar appears to be the new evil and phrases like "type 3 diabetes" has me very intrigued.

Time to do a lot more reading and start a part 2 for the post.