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Barely a week goes by without a new “health food” arriving on the market.
In many cases, the health claims are bogus and don’t have any real studies behind them.
This appears to be the case with an oil called grape seed oil.
Due to the high amount of polyunsaturated fats and Vitamin E, it is being marketed as healthy.
It is claimed to have all sorts of health benefits… including lower cholesterol and a reduced risk of heart disease.
The problem with many of these so-called health foods is that they aren’t healthy at all.
In some cases, they are downright harmful.
In this article, I’m going to take a closer look at grape seed oil and try to separate the facts from the fiction.
Grape seed oil is processed from the seeds of grapes, which are formed as a by-product of wine making.
Making this oil is actually a brilliant idea from a business perspective.
For thousands of years, wine manufacturers have been left with tons of this useless by-product, grape seeds.
Due to modern technological advances, they are now able to extract the oil from the seeds… something that wasn’t possible a hundred years ago.
The oils are usually extracted in factories using an industrial process. It involves high heat and various chemicals… which includes the toxic solvent hexane.
The “healthier” types of seed- and vegetable oils are “cold pressed” or “expeller pressed” – this is a much more natural way to extract the oil from the seeds.
If your oil doesn’t explicitly state how it is processed, then you should assume that it was extracted using chemicals like hexane.
Bottom Line: Grape seed oil is extracted from grape seeds, a by-product of wine making. This process usually involves various chemicals, including the toxic solvent hexane.
The health claims for grape seed oil are based on the supposedly high amounts of nutrients, antioxidants and polyunsaturated fats.
But here’s a newsflash… most of the nutrients and antioxidants (including the proanthocyanidins) from grape seeds are not present in the oil (1).
After it has gone through the intense chemical extraction process, most of the good stuff has been filtered out.
The only nutrient left in there in any significant amount is Vitamin E. A tablespoon contains 3.9 mg of Vitamin E, which is 19% of the RDA (2).
However, calorie for calorie, grape seed oil is NOT an impressive source of Vitamin E.
Other much better sources include nuts, spinach and various others… these foods also contain a ton of other beneficial nutrients instead of just Vitamin E alone.
The fatty acid composition of grape seed oil is:
The marketers are quick to point out that this product is low in cholesterol and “dangerous” saturated fats.
But in recent years, saturated fat and dietary cholesterol have actually been proven to be harmless. The whole “artery-clogging” thing was a myth (3, 4, 5, 6).
One of the claims is true though… grape seed oil is very high in polyunsaturated fats.
However, it is important to keep in mind that there are two main kinds of polyunsaturated fats… Omega-3s and Omega-6s.
We need to get these two types in a certain balance in order to maintain optimal health. Most people are eating too few Omega-3s and way too many Omega-6s (7).
Many studies show that too many Omega-6s lead to poor health and disease (8, 9).
As it turns out, grape seed oil contains mostly Omega-6 fatty acids, the bad kind.
In several cases, grape seed oil has also been found to contain harmful levels ofPolycyclic Aromatic Hydrocarbons (PAHs) – substances that are known carcinogens in animals (10).
Really… there is nothing positive to be said about grape seed oil. It is bad news all around.
Bottom Line: The only micronutrient found in grape seed oil is Vitamin E. This oil is also very high in Omega-6 fatty acids, which most people are eating too much of already.
I did not manage to find a single human study on grape seed oil.
However… it is very similar to other seed- and vegetable oils like soybean oil, corn oil and safflower oil.
The health effects of grape seed oil should be very similar to these other oils, because the fatty acid and nutrient composition is similar.
The problem is… there are plenty of studies showing that these oils have harmful effects in humans.
It is true that seed- and vegetable oils can lower LDL cholesterol, but in this case it does NOT translate to a reduced risk of heart disease.
In fact, there have been several controlled trials where these oils increase the risk of heart disease in humans (11, 12, 13).
There is also a study showing that the amount of Omega-6 in cell membranes (grape seed oil is very high in Omega-6) is positively correlated with heart disease risk (14).
Then there are studies showing that a high Omega-6 intake can increase inflammation in the body, potentially raising the risk of all sorts of diseases (15).
The truth is… seed oils in general are extremely unhealthy, despite what some people would have you believe.
If anything, grape seed oil is even worse than the others… because it contains an even higher amount of Omega-6 fatty acids.
Bottom Line: Many studies show that seed oils lead to harmful effects on health, including a drastically increased risk of heart disease.
Grape seed oil has a high smoke point.
For this reason, it is advertised as a good choice for high heat cooking like frying.
This is based on a huge misunderstanding… the smoke point of an oil is NOT the determinant of whether it should be used for cooking or not.
The number of double bonds in the fatty acid molecules is much more important.
Polyunsaturated fats are called poly (poly=many) because they contain many double bonds.
These double bonds are reactive and tend to react with oxygen when heated, forming harmful compounds and free radicals (16).
Because grape seed oil is so incredibly high in polyunsaturated fats, it really is one of the worst oils you could possibly use for cooking.
The healthiest cooking oils are those that contain mostly saturated fats (like butterand coconut oil), because they don’t have double bonds and are therefore less likely to react with oxygen when heated.
Grape seed oil isn’t all bad… there are a lot of people who claim that it is good for moisturizing hair and skin. It is also used in massage and aromatherapy.
For this reason, it may have some topical benefits.
But really… this oil should NOT be eaten. There is nothing healthy about it.
The Vitamin E amount is not impressive when you consider the high amount of calories and most of the antioxidants from the grape seeds do not make it into the oil.
What we’re left with is a highly refined oil loaded with inflammatory, damage-prone Omega-6 fatty acids, which most people are already eating way too much of.
If good health is what you are after, then avoid grape seed oil like the plague.
P.S. Discover the world's best source of evidence-based nutrition and weight loss information on the next page.
Grapeseed Oil
Grapeseed oil is pressed from grape seeds left over from wine making. It is believed to have very little saturated fat, is filled with good fat, has a very mild taste. It is considered good for cooking and frying, but am afraid I have had little experience with it.
• What is it made from: oil extracted from rapeseed. In the last few years there's been a surge in artisanal, British, "cold-pressed" rapeseed oils, which are marketed much like single-estate olive oils. Unlike olive oil, rapeseed doesn't go toxic at high heat, while a smoke point higher than that of olive oil makes it marginally more suitable for frying
• Best for: roasting potatoes, frying
• Worst for: it has a very subtle flavour, so is not to everyone's taste fordrizzling
Grapeseed
Extracted from grape seeds, this versatile oil is usually mild in flavor, but imported ones may have a grapy flavor and aroma. A good choice for cooking over high heat.
Monounsaturated: 17% | Polyunsaturated: 73% | Saturated: 10%
Best uses: Use this all-purpose oil for sautéing, roasting and in salad dressings.
Grapeseed Oil
Grapeseed oil is light green in color, and is prized by restaurant chefs for its high smoke point (420˚)—but also for its clean, plays-well-with-others taste. It’s often used in vinaigrettes because it is less expensive than EVOO, and allows other ingredients (like specialty oils or herbs) to shine through.