For decades, the overarching advice has been to cut down on saturated fat. This advice is so widespread and engrained into our society that we very infrequently, if ever question it. Indeed, low-fat products overwhelm us at the grocery store and have even infiltrated your local coffee shop, but are they really better for you?
This is a topic of extreme controversy. It’s also one of the few topics in the health and medical world that has extremely reputable and knowledgable experts on both side of the argument. As if it isn’t already hard enough to sort through all the crappy information out there already, it becomes almost impossible to sort it all out when the current science is all over the map.
But, that’s exactly what I’m going to attempt to do.
What the Mainstream Authorities Say
As of right now (2014), the recommendations from mainstream authorities on the subject are as follows:
World Health Organization. The WHO decided in 2003 that the “intake of saturated fatty acids (SFA) is directly related to cardiovascular risk.” They recommend restricting your daily intake of SFA to less than 10% of your total dietary intake per day.
The Mayo Clinic. Citing the Dietary Guidelines for Americans, the Mayo Clinic considers saturated fats to be potentially harmful as of 2010, and thus recommends reducing your intake of foods rich in saturated fat.
British Dietetic Association. The BDA has found good evidence while systematically reviewing randomized controlled trials that reducing saturated fat reduces morbidity in patients with cardiovascular disease.
The American Dietetic Association and Dieticians of Canada. Along with their British counterparts, they hold that epidemiological studies have shown a positive association between the intake of SFA and the incidence of Coronary Heart Disease.
I could go on and on here, with the Canadian Heart and Stroke Foundation, the American Heart Association, the British Heart Foundation, the National Heart Foundation of Australia, the World Heart Federation, the US Department of Health and Human Services all have the official stance that saturated fat is a risk factor for cardiovascular disease (CVD).
Reading this probably comes as little surprise to you, as it did me, at first. There is, however, more to the story.
The sciences of medicine and nutrition are a little like technology. They move at an ever-increasing rate. What was once believed to be truth yesterday, may very well be called into question today, and proven to be wrong tomorrow (albeit, not usually this quickly). Not only that, but trying to find out the definitive cause for heart disease is an incredibly complex issue, to which their is no one, lone villain.
What New Research Says
Particularly since 2008, there has been a vast amount of research and reviews done on the evidence that has been compiled on the topic of saturated fat in the past 60 years. Much like opening a cold case file for an old crime, researchers have parsed over the data with fresh eyes and a new knowledge base, looking to tie the evidence together for a conclusive answer to this question one way or another.
The answer is far from clear as of 2014, and the search for it has perhaps created more questions than answers. If someone forced me to to summarize the result of these studies in a word?
While that may seem to not help us at all, it actually tells us more than you think. It tells us that the once strong and almost immovable bond between saturated fat and CVD is weakening amongst the elite of the scientific community, and that there are likely many more things at play when it comes to Cardiovascular and Coronary Heart Disease than just saturated fat.
Based solely on the new evidence that has popped up in the last 4 years, there does not appear to be a unanimous agreement regarding the role of SFA in CVD. The fact that this dogma is no longer universally supported means that there is either something wrong with the concept, or that the issue is far more complex than it seemed at first sight. Likely, a little bit of both.
Even some of the very institutions that are listed above have reviewed the research and reanalyzed their own stance on saturated fat over the past few years. Although they haven’t officially haven’t changed their stance on the issue (yet), their findings are highly relevant to this discussion. The studies:
- In 2009, the King’s College in London found that some evidence suggested a negative influence of some kind on vascular function from saturated fat, but that the experimental evidence did not support this convincingly.
- In 2009, the pooled results of 11 cohort studies supported by the National Heart, Lung, and Blood Institute, the National Institutes of Health, amongst others, found that substituting polyunsaturated fatty acids in place of saturated fatty acids led to a 13% decrease in Coronary events and a 26% decrease in Coronary deaths.
- In 2009, a systematic review by the Heart and Stroke Foundation of Canada of previous cohort studies and randomized trials concluded that there was “insufficient evidence of association” between saturated fat intake and Coronary Heart Disease. Instead, they point to strong evidence of protective factors such as the mediterranean diet and vegetables, and harmful factors such as trans fats and foods high on the glycemic index.
- In 2010, the National Heart, Lung, and Blood Institute found, upon a systematic review of the evidence, that substituting polyunsaturated fat for saturated fat led to a 19% reduction in Coronary Heart Disease.
- In 2010, the Nutrition journal stated that the evidence associating dietary saturated fat with increased risk of CVD is inconclusive.
- In 2010, the American Journal of Clinical Nutrition found that the risk of Coronary Heart Disease (CHD) is reduced when saturated fatty acids are replaced with polyunsaturated fatty acids, but that there was no clear benefit in replacing saturated fats with carbohydrates (which often occurs).
- In May of 2011, the Journal of the American Dietetic Association published a summary of its 93rd conferencing on the topic of saturated fat. Their official statement:
“Researchers agree that replacing saturated fat with healthy polyunsaturated fats is beneficial for health and [Cardiovascular Disease],” while, “the evidence against saturated fat may not be as strong as dietary guidelines have interpreted, [it is clear] that polyunsaturated fatty acids (especially) and monounsaturated fatty acids are healthy fats”, and that while there is room for saturated fats within the diet, “[they] should not be viewed as good for you.”
- In 2011, a massive systematic review from the Cochrane Library analyzed 48 studies that were done between 1965 and 2009, comprising of over 65,000 participants. They found that there is a “small but potentially important reduction in the cardiovascular risk on modification of dietary saturated fat, but not a reduction of total fat, in longer trials.” They found that reducing saturated fat and/or modifying dietary fat reduced the risk of having a cardiovascular event by 14 percent, but that there was no reduction in mortality. They go on to say, “there are no clear health benefits of replacing saturated fats with starchy foods (carbohydrates).”
Translation into English
As you can see, many of the studies agree on the same points. As you can also see, some of the studies disagree on the other points. It goes without saying, that the book has not closed on the subject. It is extraordinarily complex, and there are multiple factors that come into play when trying to identify risk factors and causes of both CHD and CVD.
When taking the results from the above reviews and studies into consideration, it is important to better understand how they worked. When many of the studies reduced the participants intake of saturated fat, they replaced it with poly or monounsaturated fats. They found a positive effect in this, and therefore reported that saturated fat was a significant causative factor in CVD and CHD.
What they didn’t consider, and what most health authorities haven’t considered until very recently, is that these results may not necessarily be due to the negative effects of saturated fats, but the positive, protective effect of the replacement nutrients.
It is a confirmed fact that replacing saturated fats in your diet with polyunsaturated fats will lower your risk of CVD and CHD. It’s also been discovered that replacing saturated fats with carbohydrates is not an effective strategy if you’re after heart health, and that it may even lead to increased risk of CVD and CHD.
The Take Home Facts:
- There is widespread conviction amongst health authorities that saturated fat plays a role in Coronary Disease, but that role is currently still up for debate in many professionals mind’s.
- Recent studies show that saturated fat is only correlated with heart disease, but no clear, causal link has yet to be pinpointed.
- The replacement of saturated fats with polyunsaturated fats is proven to decrease your chances of CHD.
- The replacement of saturated fats with carbohydrates (which is what the majority of the population has done) has no known benefits, and does not decrease your chances of developing CVD or CHD.
How Should Saturated Fat Fit into Your Diet?
There is room in your diet for saturated fat, but it shouldn’t necessarily be viewed as good for you. If you decide you want to avoid it completely, that’s fine. According to the 2011 Dietary Guidelines for Americans, by the USDA and US Department of Health and Human Services, the human body makes more than enough saturated fatty acids to meet its own needs and it does not require more from dietary sources.
However, just because you shouldn’t necessarily seek it out as a health food, doesn’t mean you can’t consume it in moderation. I believe there is insufficient evidence to axe it from your diet completely. However, why not try replacing as much saturated fat as you can with the healthier alternative, polyunsaturated fat? Doing this is proven to reduce cardiac events, after all.
How much saturated fat should you consume per day? I’d stick with the WHO’s recommendation of 10% of your total dietary calorie intake max. Get the rest from polyunsaturated fat sources.