Everything We Thought We Knew About Saturated Fat Might be Wrong
Could it be that the saturated fat and heart disease link we’ve heard about for so long now could in fact be wrong? A new, significant research analysis effort certainly puts it in doubt.
In an international research collaboration led by researchers at Cambridge University, London and published this month in the peer-reviewed journal Annals of Internal Medicine, scientists have carried out a systematic review and meta-analysis of 72 studies, 45 cohort and 27 randomized control studies, from across 18 countries and involving more than 600,000 people, so that they could analyze what the data actually says about saturated fat and heart disease.
The researchers examined things like total saturated fatty acid consumption, total monounsaturated fatty acid consumption and trans fatty acid intake, as well as looking at specific types of fatty acid consumption. They compared this to risks of developing heart disease and higher cholesterol levels over a lifetime. You can find a more detailed breakdown of what they studied and how here, but for our purposes these were the main areas of interest.
The Results: Link Between Saturated Fat and Increased Risk of Heart Disease ‘Unproven’
The researchers primarily found that this analysis of the data does not support the widely held belief that saturated fat can be linked to heart disease. They also found that the commonly held notion that so called “good fats” or polyunsaturates can protect the heart isn’t confirmed by this analysis either. The research did, however, find support for the idea that trans fatty acid intake is associated with a significant increase in coronary heart disease risk.
What is likely to be an area for future study is that the researchers found specific fatty acids had very different effects on the body even when they came from the same “family” of acids, some harmful but others that appeared to prevent coronary heart disease. It could be, therefore, that it could be higher concentrations of very particular fatty acids might increase heart disease risk, but that has yet to be ascertained.
Of course, we can’t talk about this research without recognizing its limitations, one of which was that the several of the studies included people with pre-existing conditions and so that means that the results may not necessarily translate for a healthy population. However, because of its scale and level of detail, the analysis is being treated as significant.
Does this Mean We Should Eat Fatty Acids Now?
This research, though very detailed, is only a first step in properly examining the link — or lack thereof — between fatty acids and heart disease, and to put this in perspective it’s important to recognize the backdrop behind this research.
Saturated fats are found in many different types of food but are especially abundant in things like meat and dairy, as well as palm and kernel oils that are often found in sugary treats like candy bars and other sweet food products.
The link between saturated fat and heart disease is decades old, with research going back to the 1950s suggesting that there seemed to be a link. A major study that really cemented the notion of the fat and heart disease link came in 1977 from Ancel Keys who conducted the “seven countries study,” which purported to find damning proof that countries which consumed the most saturated fat also had the highest levels of heart disease. The study had a number of problems though, not least of which was the way in which Keys appeared to have purposefully selected data from countries in a way that could (and almost certainly did) bias the data toward this result.
Nevertheless, international food agencies and dietary groups began recommending lowering saturated fat intake and, for the most part, replacing it with higher carbohydrate intake and healthy protein sources. However, the link between heart disease and saturated fat was never as solid as the recommendations might have led the general public to believe. Now, the new analysis shows that those recommendations may have been hasty.
It should be pointed out that technically this isn’t new information: individual studies have for a while now shown that the once golden rule of dietary advice, that saturated fat is bad for us, might be wrong. However, this analysis is so comprehensive that it helps to confirm that there probably isn’t sufficient data to underpin the current consensus of the strong link between high saturated fat intake and potentially fatal heart disease.
Yet, while the analysis may not have turned up evidence of such a link, there are still a number of reasons to avoid foods with a high saturated fat content. Such foods tend to be highly calorific and lacking in other nutrients, which in turn increases the risk of weight gain and obesity. Those foods also can carry high amounts of sugar which again adds to a number of health problems including the risk of developing diabetes.
So, while this research could ultimately prove to be one that greatly changes our understanding of saturated fats, it’s probably still best to have only small portions of those foods in our diets.
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