Browse evidence-based analysis of health-related claims and assertions
Over the last 50 years, the fat stored in our bodies has changed—more of it comes from processed vegetable oils, which might be changing how our body burns energy.
Descriptive
The highly processed vegetable oils we eat a lot of today—like soy and canola oil—can cause damage inside our cells because they break down easily and lack protective nutrients, which might mess with how our body uses energy.
Mechanistic
Even though many countries have banned artificial trans fats, you can still find them in baked goods, fried foods, and snacks in places where rules aren’t enforced or labeled clearly.
Eating artificial trans fats might change how your genes work without changing the DNA itself, possibly making you more prone to inflammation and fat buildup in the liver — but we don’t yet know how this works in people.
Artificial trans fats make your body produce more inflammation and cell damage, which can lead to heart disease and other chronic illnesses.
Trans fats from dairy and meat don’t seem to harm cholesterol or cause inflammation like the ones made in factories — some might even be a little good for you.
Correlational
Artificial trans fats make the liver produce more fat, cause more cell damage from oxidation, and trigger inflammation, which can lead to serious liver scarring over time.
Eating foods with artificial trans fats raises the bad cholesterol and lowers the good cholesterol, making heart disease more likely.
Different fish scraps make oils with different smells after cleaning — tuna oil smells one way, seabass smells another, because they have different fats.
Fish waste oil starts with more natural vitamin E than wild fish oil, but cleaning it removes most of it — yet the oil still lasts longer, so something else is protecting it.
Cleaning fish oil with steam makes some bad smells worse in some oils, and doesn’t get rid of all the fishy odor.
Cleaning fish oil with heat and chemicals makes it last longer without going rancid, even though it loses some natural antioxidants.
Oil made from tuna scraps has just as much of the healthy omega-3 fats as expensive cod liver oil.
Quantitative
Turning fish waste into oil and cleaning it with chemicals makes it cleaner and safer to use, without losing the healthy fats.
How well the clay soaks up bad stuff matters more than how acidic it is when cleaning palm oil.
If the raw palm oil is of low quality, it creates more harmful chemicals when heated during refining.
Using a lot of phosphoric acid to clean the oil and then a special clay removes almost all of another harmful chemical in the final product.
A special type of clay used to clean oil works better at removing harmful chemicals if it can trap more stuff, not because it’s more acidic.
Using water to clean raw palm oil before refining can cut down one harmful chemical by about half.
Scientists can estimate how long it takes for half of the healthy compounds in olive oil to break down when it’s heated at different temperatures.
Scientists can calculate exactly how fast the healthy parts of olive oil break down when heated at different temperatures, using a mathematical model.
The amount of heat energy needed to break down the healthy compounds in olive oil doesn’t change much, no matter how hot you heat it (within the range tested).
When you heat olive oil really hot, the healthy compounds called polyphenols break down faster the longer and hotter it gets.
When you heat olive oil, it gets more gunk in it — and the hotter you go, the more gunk forms. Some oils (like Armonia) get way gunkier than others (like Manzanilla).