Ask The Dr.

Some vegetable oils are as bad for your health as sugar. Here are five reasons why— and what to do about it.
Lemon scented olive oil

By Dr. Frank Lipman

For years, my wellness colleagues and I have designated sugar as the No. 1 dietary evil, a true destroyer of health. And although most people still eat way too much of it, U.S. sugar consumption is finally on a slow decline. But the battle for your health is far from over. There is another killer, “vegetable oil,” on the loose. The stuff is as big a problem as sugar, and should be eliminated from our diets just as quickly. Here’s a top-line list on why—and what to use instead:

1 VEGETABLE OIL HAS NO VEGETABLES! Many healthy fats come from plants, including olive, walnut, coconut, palm and avocado oils. But some of the unhealthiest fats around are also plant-based, and Big Food’s marketers know that if they slap the phrase “vegetable” or “heart-healthy” on a label, consumers will buy it for the presumed benefits. Trouble is, there’s no vegetable benefit or nutrients to be had in that gleaming bottle of golden vegetable oil. What’s in there is an industrial oil product better suited for cleaning and lubricating machinery.

2 KNOW THE ENEMY. I refer to vegetable oils like canola, corn, cottonseed, safflower, sunflower, rice bran and soy as “industrial oils” because they were never part of the human diet until we developed factories to produce them. Though technically “plant-based,” these oils are made with barely edible seeds, grains and legumes that our bodies can’t properly break down and digest. Refining these ingredients into something edible involves high heat and chemical solvents, like the neurotoxic solvent hexane, to remove the unappetizing taste and smell, and enhance the oil’s appearance and pourability.

3 VEGETABLE OIL INFLAMES YOUR BODY. As if the whole solvent issue wasn’t unappealing enough, another big reason to avoid vegetable oils is because they’re a very unstable form of fat. Unstable fats oxidize and turn rancid easily, forming free radicals. These free radicals damage healthy cells, and trigger inflammation, which we all should avoid at all costs. Granted, any fat can oxidize and release free radicals, but the polyunsaturated fats found in vegetable oils are the most unstable, and all it takes is some light exposure to kick off the oxidation process, even before you crack open a bottle. Planning on sauteing dinner with a bit of vegetable oil? Heating the pan will further destabilize and oxidize the polyunsaturated fats and unleash free radicals. Why risk adding more inflammation to your body? One more cause for concern: The severity of COVID-19 outcomes are increasingly being linked to inflammation. Ditching vegetable oils has never been more essential.

4 INDUSTRIAL OILS ARE GOOD FOR MACHINES, NOT YOU. Take, for example, the sounds-healthy-but-it’s-not canola oil, a made-up food derived from rapeseed. “Canola” is said to stand for “Canadian oil, low acid,” because it was originally developed in Canada and the word “canola” had a nice marketing ring to it. So, no vegetables, no benefits, highly refined and plenty of free radicals. It’s the worst of all worlds.

The trouble is, these cheap, readily available, extended- shelf-life industrial oils are so prevalent in the foods many of us eat every day—restaurant food, processed foods, baked goods, prepared foods and packaged foods—it’s easy to consume lots more than you think you are. And all that unstable, polyunsaturated fat threatens your health in several important ways:

They’re often made from genetically modified crops. Genetically modified organisms (GMOs) can have harsh consequences for your health, destroying good bacteria and altering your microbiome. An imbalanced microbiome leads almost immediately to weight gain and inflammation, and all the symptoms of un-wellness that inflammation brings on.

They throw off the balance of omega-3s and omega- 6s. Omega-3s are a type of fat found in fish, flax, nuts and seeds. Omega-6s are a type of fat found most frequently in meat, dairy products, eggs and other animal fats—but also in industrial oils. Ideally, your ratio of omega-6s to omega-3s is 1:1. But our modern consumption ratio is more like 10:1 or even 25:1, because most of us eat too much industrially raised meat and poultry and not enough grass-fed meats, wild fish, nuts and seeds.

To help keep your omega 6:3 ratio on track, trade processed foods for fresh, whole foods. Eat few—if any— fried foods. Ditch baked goods, prepared foods, and Frankenfoods like nondairy creamers. Don’t eat or cook with faux-butter products or vegetable shortening.

5 EMBRACE TRULY HEALTHY OILS WITH REAL BENEFITS. Know what you’re buying, cooking with and eating! Pay attention to labels, but get the real lowdown on ingredients, and how items are processed, from research- intensive sites like the Environmental Working Group’s Food Scores Guide (, rather than the manufacturers’ ingredient lists, which are virtually impossible to decipher (unless you’re a food scientist). Ultimately, what you want when it comes to oils are stable, unrefined, minimally processed saturated fats—not polyunsaturated—which support the health of your heart, brain, gut, immune system and hormones, and help tamp down inflammation.

1| Look for cold-pressed oils, to ensure they haven’t been treated with heat or solvents. If that oil is refined, leave it behind.

2| Look for oils in dark glass or metal packaging to prevent light exposure. Clear plastic is a major no-no, and a big clue that the stuff inside the bottle is most likely low-grade, industrial crap.

3| Buy the highest-quality oil possible—either from small- batch producers, or organic or artisanal producers at the farmers market—to minimize concerns about chemical pesticides or genetically modified ingredients.

4| Make oils-with-benefits your top choices, opting for fruit and nut oils, like extra-virgin olive oil, walnut oil, coconut oil, sesame oil, flaxseed oil, macadamia oil, almond oil and avocado oil, as well as palm oil—but only if it’s responsibly and sustainably sourced.

5| For those who prefer to cook with animal fats—like butter, ghee, duck fat and lard—look for it to come from organic, grass-fed, pasture-raised animals.

6| For everyday use, extra-virgin olive oil works well for sauces, light sauteing and salad dressings.

7| For higher-heat cooking and for those who follow the vegan path, coconut oil is an excellent and reasonably priced go-to.

8| Always store your oils far away from sources of heat and light to prevent rancidity. You can also wrap them in tinfoil for an additional layer of protection.

9| Clear the kitchen of “vegetable” oils like canola, corn, cottonseed, safflower, sunflower, rice bran and soy.

10| Steer clear of vegetable oil-soaked fast food— particularly fried foods—as well as processed and prepared foods, including most bottled salad dressings.