The idea that eating more saturated fat will increases our risk of heart disease is claimed to be ‘well-established’ according to most nutritional commentators. The fact is, as I disclosed here, there really isn’t any good evidence to support this assertion. Three major reviews in recent times have failed to find evidence demonstrating that saturated fat causes heart disease. Getting doctors, dieticians and governments to release their grasp on this concept has not been easy. I sympathise – there was a time I believed with all my heart that saturated fat caused heart disease. Note, I write ‘with all my heart’. My head knew no such thing, and the reason was simple: at that time I’d never thought to check the facts. Such was the certainty with which I had been told the ‘saturated fat causes heart disease story’, it didn’t even occur to me to look at the evidence. When I did, I was truly aghast at what I discovered.
I had another moment of revelation today, on reading a study which is published on-line and due to appear in next month’s edition of the American Journal of Clinical Nutrition [1]. This study followed more than 58,000 Japanese adults over a 14-year period, and assessed the relationship between their saturated fat intake and risk death from a variety of ‘cardiovascular’ diseases.
Before we go any further, let’s go through some terminology. ‘Cardiovascular disease’ is an umbrella term that essentially covers stroke or conditions related to the heart. Heart-related causes of death include heart attack (myocardial infarction), cardiac arrest (stopping of the heart) and heart failure (when the heart becomes too weak to support life). Strokes come in two main types: ischaemic and haemorrhagic. Ischaemic strokes are the most common types of stroke, and are caused by a blocking of one or more blood vessels in the brain. Haemorrhagic strokes are caused, on the other hand, by bleeding in the brain. These come in two main forms, ‘intraparenchymal’ and ‘subarachnoid haemorrhage’. OK, enough of the technicalities.
For each of these conditions, the authors of the study compared risk of death with intakes of saturated fat. Here’s a summary of what they found:
Compared to those eating the least saturated fat, those eating the most were found to be:
At NO increased risk of death due to heart attack, heart failure or cardiac arrest.
At NO increased risk of death due to subarachnoid haemorrhage.
At REDUCED risk of death due to intraparenchymal haemorrhage (52 per cent reduced risk)
At REDUCED risk of death due to ischaemic stroke (42 per cent reduced risk)
At REDUCED risk of death due to stroke (all types of stroke lumped together) (31 per cent reduced risk)
And, wait for it….
Higher intakes of saturated fat were found to be associated with a REDUCED RISK OF DEATH FROM CARDIOVASCULAR DISEASE (18 per cent reduced risk)
Now, at least some of these findings should come as no surprise to followers of the scientific literature. We know that saturated fat has consistently not been linked with heart disease risk. Plus, several previous studies have linked higher saturated fat intakes with a reduced risk of stroke, principally haemorrhagic stroke. One theory here, put forward by the authors, is that low levels of cholesterol (perhaps secondary to low saturated fat intake) leads to thin and weak blood vessels in the brain (that are more likely to haemorrhage).
However, the fact that this study linked higher saturated fat intakes with reduced risk of cardiovascular disease was a bit of a shock to me. While the finding is in the results table of the paper, I can’t find any mention of it elsewhere. The authors do make this comment, however: “Assuming that the inverse association between SFA [saturated fatty acid] and stroke mortality is causal, it would nevertheless be inappropriate to recommend an increased consumption of SFA-containing products to the general Japanese population, because it might increase population levels of total cholesterol and the risk of IHD [ischaemic heart disease].”
The authors are entitled to express any opinion they like, but this one is simply not supported by their own data. According to their findings, if the Japanese were to increase their saturated fat intake, heart disease deaths would stay the same, stroke deaths would go down, and so would deaths due to cardiovascular disease overall.
References:
1. Yamagishi K, et al. Dietary intake of saturated fatty acids and mortality from cardiovascular disease in Japanese: the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC) Study Am J Clin Nutri 2010;92(4):759-765
It is amazing how researchers can do a study only to then turn around contradict the findings in the conclusion. People just don’t like to go against the common wisdom do they?
The study is reductionist as it only addresses a single food component and not whole foods. It would be nice to know what foods the saturated fat was obtained from. From my experience in Japan, beef and pork are consumed but no (or negligible) milk or butter and I don’t think they cook with saturated fats or use sigificant processed pork. Also there are confounding factors such as use of large amount of salt (soy sauce) and white rice. But the biggest confounding factor is the amazingly high consumption of fish (beautiful fresh sushi rolls are available in every Japanese supermarket !). Consumption of large amounts of oily fish and fish oils is well known to increase blood clotting times.
Therefore I don’t think the study has any significant relevance to the west where huge amounts of saturated fat from cow’s milk and milk products, processed pork and (in the US) grain fed beef are eaten.
What one concludes from this study is important. – it does not provide any evidence that saturated fat form milk is beneficial for instance – nor does it demonstrate that there is any point in consuming extracted saturated fats or even any high amounts of saturated fats. The results may just be due to the higher fish consumption amongst the lower saturated fat eaters.
As regards fat containing foods a good balanced and natural lipid profile should be the objective. The safest thing to conclude is that one should eat a wide range of natural whole foods and avoid refined and processed foods and food from unnaturally fed animals. This means eating lamb, grass-fed beef, venison, wild game, sea fish, nuts, seeds, olives, avocadoes, coconuts etc without obsessing on anything. If milk is consumed it should be unhomgenised full fat milk from Jersey or Guernsey cows – the only safe spread is butter but this should be from grass fed cows – New Zealand (with its dark yellow colour) is probably the best. It also means avoiding eating all refined and processed fats and oils (though if one has to fry a minimal amount of coconut oil, palm oil, ghee or olive oil could be used), which are nutrition poor and avoiding processed meats such as bacon and salami .
I agree with Dennis about the confounding factors. Nevertheless, in my knowledge the strongest evidence re: stroke protection and SFA still comes from US (Gillman 1997 and Iso 2003).
It would also be interesting to know how PUFA in replacement of SFA would affect stroke incidence. Recently Mozaffarian (2010) and Jakobsen (2009) have shown that this switch strategy modestly prevents coronary outcomes but they did not analyse strokes per se.
Fat debate was heated again here in Finland. I responded to discussion recently.
I am given to understand that saturated fat consumption is, however, associated with an incresed risk for certain cancers such as prostate. see Dr. Dean Ornish and references he cites
Jim
I agree with you. I would not advocate a high fat diet. But I think that fat intake should have a natural lipid profile representative of wholefoods including a mixture of saturated, monounsaturated and polyunsaturated fats – perhaps in a 1:2:1 ratio but nowhere near the total amount of fat that is typically consumed in the west. But we do need some fats and I think that the Ornish/MacDougall etc diets have too little fat for long term use. If one eats only wholefoods and no added fats, including the fat containing foods I mentioned in my earlier comment as well as loads of fruit and veg (10 portions a day is about right) one will not consume large total amounts of fat. The ridiculously large amounts of fat in the western diet are a result of eating processed foods. Also I think eating a wholefood diet is cancer protective so any effect of a small amount of saturated fat may not be significant in this case.
Dennis I agree wth your comments completely. I myself have a relatively modest protein (I try for about 70gms/day lots of fish, chicken and grass-fed beef)): low refined carb (see exception below) but I load up on veggies (raw and cooked) Plus relatively high healthy fat (along the lines you suggested) diet about 45 to 50% of calories. My down fall is that I consume about 2 or 3 pints of lager beer per day. Sigh… When I stop I do get a little depressed. Cheers!
The new “study” that Dean Ornish is so fond of is a total sham. Some of the low carb participants were getting 60% of their calories from carbohydrates…which is NOT low carb by any stretch of the imagination.
http://www.fathead-movie.com/index.php/2010/09/09/the-atkins-study-ahem-ahem-according-to-ornish
This quite new case-control study from France casts some controversy to the association of SFA and strokes. In this study high SFA intake was associated with higher stroke incidence, and interestingly omega-6 fatty acids were protective. http://bit.ly/9bdkkv
Why do Eskimos, who typically eat a diet loaded with animal fat, have very low rates of heart disease?
The answer is that high cholesterol isn’t the cause of heart disease – oxidised cholesterol is. I am wondering what we might learn if the Japenese study included measuring individuals ORAC, (Oxygen Radical Absorbance Capacity,)against the ingestion of saturated fat.
I agree that it is not fat, per se, which causes heart attacks. However though Eskimos may not suffer from heart attacks, they have high risk of stroke and there are other risks from high levels of fat, such as cancers etc.
Just because we now have different (and probably justified) scapegoats for heart attacks – such as refined carbs and fats and glycosylated proteins – it does not mean that it is safe to consume high levels of fat. Stick to a more balanced diet such as in my comment 6.
Saturated fat is not a “thing” that can be considered as having identical properties any more than a “dog” can be considered as having identical properties.
A hydrogenated fat is saturated, but highly inflammatory and damaging, especially in its trans forms. Are these lumped into the study of “saturated fat”?
Coconut oil is a saturated fat, but it does not come with antibiotics and hormones dissolved within it (pesticides maybe).
Butter is a saturated fat, but one the body is designed to handle. However, put dissolved hormones, antibiotics and hormones into it, then it is unfair to count its effects as if it were pure butter.
My point is, with all the universities in the world (many government funded), with all the billions spent on cardiac disease, and with all the misery caused by misinformation, HAS NO ONE THOUGHT TO DO A GOOD STUDY IDENTIFYING THE DIFFERENT SOURCES AND TYPES OF SATURATED FATS?
With modern computers, how hard can it be?
Rather than looking at fat per se we should eat a diet that our ancestors ate and produce food in the most natural way possible.THey would have eaten fat as it came in fish, nuts and meat but no butter, oils as they would not have been able to process them.
In as much as Dear Dr Briffa’s passion appears to be an informed and inquiring look at relevant studies it seems proper to focus to look for the way forward in this matter via correctly constituted and analyzed confirmatory studies. But first there has to be an awareness change that says….the sticky gooey fats we often eat do not necessarily make sticky gooey lumps that clog up our heart and brain.
Ted,
There are too many variables – we eat hundreds of different foods, each indidual food with varying qualities depending on how it is produced. Also we eat foods rather than fats, per se. Furhermore we all have different metabolisms and sensitivities. Thus neither intervention studies nor population studies can give definitive results. At most we can judge relative risks of different foodstuffs and we all make different judgments about risk – even though there are some widely held interpretations they are often hotly debated as you well know. Putting together a diet is rather like putting together a financial portfolio – everything has some risk even cash. So one looks for diversity with more of the less risky things and less of the more risky things. My guiding principles are diversity and distance from nature. T think that the nearer to nature a food is, the lower the risk. Hence wholefoods are lower risk and refined, processed and contaminated foods are high risk. Thus I eat wholefoods as naturally produced as possible (preferably wild) , with a bias to paleo foods including a very wide range of plant and animal foods , but even including a small amount of the dreaded whole grains (other than modern wheat) but very little dairy. We all look at the huge range of , often contradictory, evidence available and have to make our own judgments.
Oh and Hilda you are quite right.
To dennis: Can not agree with you more.
As a chinese, my family (probably the whole country) is fed with processed vegetable oil. But a good thing is: Large amount of vegetable are consumed (especially green leavies), some of which may never to be found in Europa, as well as in U.S.
It is true that the diversity of food and their sources makes it hardly possible to build up a firm association concerning certain diseases. Even my father, who is very much careful with what he eats, believes in most of my opinions but never loses his interests in steamed bread which is made of refined flour.
yingchun,
Thank you for your kind comment. I also have difficulty persuading my family to follow nature. But the whole world seems to believe in processed ‘foods’ due variously to tradition, fashion, advertising or necessity. I wonder whether in reality we could make more efficient use of our food by not using it for refining and processing – but I suppose millions of jobs would be lost and this is an unrealsitic prospect. In Japan, I think it is, that they say one should eat at least forty different foods a day and I suspect cninese tradition has similar thoughts or sayings.
A great comment from dennis regarding complexity of nutritional research and its interpretation! Perhaps Mente et al 2009 (in conclusion of his extensive meta-analysis) and Mozaffarian & Ludwig (2010 JAMA commentary) are right when they advocate new approach in dietary recommendations focusing rather on food (patterns) than discrete nutrient intakes.
hi,dennis:
In china we do not advocate a diverse food intake specifically, it seems that most of the populations are just following it, thanks to the very much various foodstuffs (meat, veggies, fruits, eggs, soy products, fermented foods etc.). I can not help remembering the happy time with my mum shopping in the morning markets, around by so much fresh stuffs ~~
Some typical dishes represents the diverse topic very well. People are used to mixing several veggis together, dripped with fermented vineager, soy sauce and a little sesam oil, yummy~~
When eating meat, we are always cut them into cubes or slices and fried with various veggies. However here in Germany, I have to eat large piece of fried meat served with small amount of boiled veggies and potatoes. Without help from extra sauces, it is hard to finish the whole meat~~
BTW: One of my favorite veggie mix include a medium size onion, a big tomato and two slim peppers (a little bit hot). They are all cut into small pieces, and only salt and vineger are enough to give the spices~~
hi yinchun
I know exactly what you mean about large chunks of meat and small portions of vegetables – that is exactly how we do it over here, traditionally at home, as well as in restaurants (almost impossible to get any significant amount of vegatables in restaurants). Fortunately I am retired so we can cook at home so today we are going to have some stir fried duck (with turmeric and chili) with a huge plate of natural stir fried vegetables (onion, mange touts, bok choi, tenderstem broccoli, bean sprouts, capsicum, ginger, garlic, spring onion, corn) with lemon juice and soy sauce. We will also have some red fruit. This is how I think one should aim to eat every day.
Best wishes
Dear yinchun, cannot is one word.
I recently bought a large tub of dried red chillies and my son tells me I can grow chillies from them so I am doing just that on a south facing window cill.
Try leaving the food you don’t like, the German’s are not a wasteful people and will soon get the message – you can always ask for more vegetables. Regards, Audrey