I have read on various sources that vegetble oil is improper for a ketogenic diet. But I do not understand why.

If the fats are suppose to turn into ketones, which in turn are burned for energy instead of sugar, and since any oil is a fat, why would this stop the process of ketosis?

3 Answers 3


The general recommendation against vegetable oil has nothing to do with the oil source. The usual complain is that vegetable oils are perceived as "highly processed" and thus "not natural". Which of course is not true. You can't treat extra virgin olive oil same as margarine (aka "hardened vegetable oil"). There are many crappy products made from unspecified "vegetable oil", but it doesn't mean that all oils coming from plants are bad.

Just make sure the oil is a high quality, cold pressed one.

Sorry I can't cite any sources, but when something is a made up misconception, there are no sources to prove it's not real : /


What is bad is not vegetable oil but making decisions based on pseudoscience. There is no evidence that low carb diets will do you any good except if you are (pre)diabetic. It's not good science to do studies on prediabetic obese people, put them on a low carb ketogenic diet, measure the improvement in insulin sensitivity and then conclude that carbs are bad. That's as stupid as saying that strenuous exercise is bad for the heart because the condition of heart failure patients worsens when put on a strenuous exercise routine.

The real evidence on carbs and fats points to the complete opposite direction. A high carb, low fat diet actually improves insulin sensitivity and has many other health benefits, particularly for the cardiovascular system. We can read here:

Maybe the Africans were just dying early of other diseases and so never lived long enough to get heart disease? No. In the video One in a Thousand: Ending the Heart Disease Epidemic, you can see the age-matched heart attack rates in Uganda versus St. Louis. Out of 632 autopsies in Uganda, only one myocardial infarction. Out of 632 Missourians—with the same age and gender distribution—there were 136 myocardial infarctions. More than 100 times the rate of our number one killer. In fact, researchers were so blown away that they decided to do another 800 autopsies in Uganda. Still, just that one small healed infarct (meaning it wasn’t even the cause of death) out of 1,427 patients. Less than one in a thousand, whereas in the U.S., it’s an epidemic.

These Ugandans only got about 20% of less of their energy from fats, they were eating mostly a plant based diet. Human physiology is adapted to get most of the energy from carbs. Our ancestors living in Africa had to do without butter and oil, they would be filling their stomachs with energy from starches and fruits. You only need a small amount of the essential fatty acids Omega-6 and Omega-3, of the order of a few grams per day.

There is plenty of other evidence for this. E.g. Evidence from autopsies on US soldiers killed in action in Vietnam shows that 80% had the early signs of atherosclerosis, while only about 3% of the North Vietnamese killed in action showed such signs. The main difference is the diet, the North Vietnamese were eating a plant based diet where most of their energy came from carbs. An intervention study by Dr. Esselstyn done on heart patients who could not be operated and were deemed to be terminally ill, resulted in most of these patients reversing their symptoms and living for many more years without symptoms, see here for details.

The opposite claim that a low carb high fat diet is good for health has arguably been falsified in a huge trial. The North American population has put itself on this diet, decreasing the amount of carbs relative to the amount of fats ever more. The result? Americans are not just getting fatter, they are ballooning to extremely obese proportions at an alarming rate. People in their 40s are dying from heart disease, teenagers are getting type 2 diabetes.

So, to conclude, what's bad for you is the ketogenic diet itself, not so much the oil you want to use for this diet.

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    But assuming I am pre diabetic, would the use of this oil knock me out of ketosis? And thank you for the informative read.
    – Ro Siv
    Jun 4, 2016 at 9:14
  • @RoSiv Yo should then stick to the official health advice, while this does call for lowering carb intake, it's not a ketogenic diet. Note that exercise will help a lot but to be able to exercise well you do need to burn carbs. Energy from carbs requires less oxygen to be burned. On an extremely low carb, high fat diet, you'll struggle with doing strenuous exercise. Jun 4, 2016 at 17:42
  • This article says "plant based diets are good" and provides limited evidence. Offers no evidence against LCHF. Claims that LCHF offers no benefits except to large fraction
    – John
    Jun 9, 2017 at 11:11

Many people think vegetable oils are healthy. The word vegetable might have something to do with it. Or maybe it’s the American Heart Association — a group that’s endorsed soybean oil, corn oil, and the rest of the vegetable oils as “heart healthy” for nearly half a century[*].

Whatever the reason, what’s certain is that vegetable oils have made their way into more and more foods (especially processed foods) over the last 50 years, while fats like butter and coconut oil have been phased out.

Vegetable oils have no place on a healthy ketogenic diet. The trouble is that vegetable oils are rich in linoleic acid and other inflammatory and easily oxidized omega-6 fatty acids.

Vegetable oils are bad for your metabolism, inflammation levels, oxidative stress, weight regulation, and cancer risk.

This article will cover the science behind vegetable oils, the top seven vegetable oils to avoid, and what to use instead of vegetable oils.

For the last half-century, the American Heart Association has maintained that saturated fat is a driving cause of heart disease and that for the sake of your heart, you should replace saturated fats like butter and coconut oil with “heart healthy” vegetable oils rich in omega-6 fatty acids.

However, more and more research is coming out that suggests the exact opposite. In the last decade, several large, independent reviews of the research have found thatdietary saturated fat is not associated with heart disease[][].

The data actually suggests the opposite. Saturated fat intake is inversely correlated with stroke incidence, and may protect against alcohol-related liver disease[][].

And foods high in saturated fat — eggs, palm oil, and coconut oil — are rich in beneficial nutrients like choline, carotenoids, and medium chain triglycerides (MCTs).

When you store (or eat) fat, you store it in triglyceride form. When it’s time to use that fat for energy — on a ketogenic diet, for instance — the triglyceride is broken down into fatty acids.

Fatty acids are the building blocks of fat. There are a few different types, each with unique effects on your health.

Here are the four major types of fatty acids:

Saturated fatty acid (SFA)Monounsaturated fatty acid (MUFA)Polyunsaturated fatty acid (PUFA)Trans Fatty Acid (trans fat)

You already learned about SFA. SFAs are satiating, resists oxidation, and is stable at high heats, which makes it great for cooking. Contrary to popular wisdom, SFA is healthy.

Next come MUFAs. High MUFA intake correlates with lower blood pressure, lower blood glucose, and lower cardiovascular risk[*].

You won’t find many folks bashing monounsaturated fats. They’re the main type of fat in olive oil and avocado oil, and are prevalent in the Mediterranean Diet, which is one of the best-studied diets for longevity.

Then there are PUFAs. PUFAs can be divided into anti-inflammatory omega-3 fatty acids like the ones you find in fish, and pro-inflammatory omega-6 fatty acids like the ones you find in vegetable oil.

Finally, artificial trans fats — or hydrogenatedPUFAs. Artificial trans fats are by far the worst type of fat around. Luckily, researchers have shown how bad they are, and at this point, trans fats are illegal in most parts of the world[*].

Omega-6 PUFAs aren’t as bad as trans fats, but they aren’t great for you either. Let’s talk about why.

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