Vegetable oils are often recommended as a heart healthy replacement for saturated fat in the diet. A 2011 a report by the USDA Center for Nutrition Policy and Promotion concluded: “The evidence shows that a decrease in (saturated fat) equivalent to 5 percent of calories, replaced by (polyunsaturated fat)…decreases risk of CVD”. This view, based on epidemiological evidence, is particularly perplexing given the existence of a superior form of evidence, randomized controlled trials, which have not only evaluated this very subject but also frequently contradicted the quote above. Continue reading
I’ve previously discussed on this blog my belief that linoleic acid may have negative effect on cancer risk. Today I want to look at some experimental evidence regarding why this is. Continue reading
To my knowledge there exist no controlled dietary trials lasting long enough for us to know how replacing monounsaturated fats (e.g. olive oil, canola oil) with omega-6 polyunsaturated fats (e.g. corn oil, sunflower oil) affects death from and incidence of various diseases. C’mon researchers, get on that!
In the meantime, if we want to try and figure out which types of fat is healthier, we need to look at controlled trials which measured various health markers suggestive of disease risk. I went on a mad search for controlled trials on humans comparing the effects of monounsaturated fat and omega-6 (or n6) polyunsaturated fat on such markers. Here’s what I found:
I care about my health. And one important consideration when discussing health is death; dying really puts a damper on good health. So when I go to the grocery store and see a bottle of vegetable oil proudly stamped with a sticker about how healthy it is I wonder “Is that true?”. And when I read in a magazine about evil saturated fats I sometimes ask myself “Would replacing my butter and beef fat with corn and soybean oil reduce my chances of dying?”
Of course, extensive personal experience tells me that I would feel much crappier consuming the vegetable oils, but hey, maybe I would live longer?
I decided to examine long term controlled trials who’s only variable was pitting saturated fat against polyunsaturated fat (primarily the omega-6 variety found in vegetable oils). Let’s see what happened to mortality rates, shall we? Continue reading
The idea that gluten consumption may influence the development of schizophrenia has been the subject of a bit of discussion lately (1). Much of the speculation comes from the increased rates of gluten intolerance and celiac disease like symptoms found in schizophrenics (2,3). One major hypothesis postulates that when gluten derived peptides known as exorphins enter the blood they disturb brain function and cause schizophrenia (4,5). And while there is a correlation between gluten intolerance and schizophrenia, it’s merely that; a correlation. Not much evidence exists proving causality. It is possible that gluten is responsible, but it could be that both are symptoms of the same underlying cause. Let me explain. Continue reading
I believe preliminary evidence is coming out that shows linoleic acid is a promoter of certain cancers. Let’s examine the evidence supporting this claim, beginning with studies done on animals. Continue reading
A few months ago a study titled “Effects of n−6 PUFAs compared with SFAs on liver fat, lipoproteins, and inflammation in abdominal obesity: a randomized controlled trial” was published in the American Journal of Clinical Nutrition. This study compared the effects of polyunsaturated fat, in the form of sunflower oil, with saturated fat, in the form of butter on various markers of health. The results of this study seem to indicate that saturated fat produces higher insulin, higher levels of inflammatory mediators, a worse lipid profile, and greater accumulation of liver fat. Ouch.
Still, I think there are some problems with this study that weakens it as evidence that saturated fat is bad and polyunsaturated vegetable oils are good. Continue reading
Well, here I am. After many eons of studying nutrition in the halls of Valhalla, I have decided to bring by opinions to the world wide net. I don’t have the time to post anything of real length to begin with, so here’s a wonderful cooking show I’ve been enjoying lately.
Personally, I don’t advocate eating straight mayonnaise like the fellow in the video; too much linoleic acid. Despite his statement to the contrary, it’s probably not “good for you”.