All of those antioxidant supplements are a huge con

The INSIDER Summary:

• Antioxidants are touted as superhealthy, and you might think you should load up on them.
• But research on antioxidants' health benefits has yielded mixed (often disappointing) results.
• Experts say more antioxidants aren't always better — and that you should get your antioxidants from whole food, not supplements. 

Food and supplement companies make it seem like antioxidants are little warriors that start vanquishing diseases in your body as soon as you ingest them. It's easy to assume that consuming more of them must be better than consuming less. 

But science shows loading up on antioxidants may not be as beneficial as you'd think — some research suggests it can even cause harm. Here's what you need to know.

First, a quick primer on how antioxidants work:

Antioxidants have the power to stop free radicals, highly reactive chemicals that tear through the body, damaging cells and possibly playing a role in the development of diseases like cancer. Free radicals are an inescapable fact of life: The body makes them as a natural byproduct of digesting food, and it also makes them in response to pollution or radiation exposure. 

"Antioxidants" is the catchall name given to the hundreds — probably thousands — of chemicals that can quench destructive free radicals. The body makes a lot of its own antioxidants, but we can also get them from our diet. Some antioxidants are also vitamins — vitamins A, C, and E, to be specific — but most others aren't.

When it comes to antioxidants, more is n0t always better. 

A few decades ago, scientists began to understand that free radical damage might play a role in conditions like heart disease, cancer, vision loss, and more, according to the Harvard School of Public Health. So they decided to study what would happen if they gave people large doses of antioxidants in supplement form. 

The results have been largely disappointing.

In 1985, for instance, American researchers recruited 18,000 people at high risk for lung cancer and had some of them take vitamin A supplements. But the study was halted almost two years early because participants taking the supplements were getting more lung cancer than participants taking a placebo.

Newer research hasn't been much more promising. A 2007 review found that taking antioxidants beta carotene, vitamin A, or vitamin E could increase mortality — yes, that's the fancy scientific term for death. And while some trials have found a benefit to antioxidant supplementation, most simply haven't. 

"The supplement trials have really failed," Christopher Gardner, PhD, professor of Medicine at Stanford Prevention Research Center and member of the True Health Initiative (THI), told INSIDER. 

The antioxidant "scores" on food packages don't mean much, either. 

You've probably come across tons of foods with claims about antioxidants on the label. 

The test that companies use to make such claims is called the Oxygen Radical Absorbance Capacity, or ORAC. The problem is that it's a done in a test tube, not in humans. And just because a food has lots of antioxidant power in a test tube, Gardner explained, doesn't mean it's going to translate to a tangible health benefit in your body. 

"Even though [there's an antioxidant] in a food, you would have to absorb it without breaking it down," Gardner said. "Then it would have to be delivered to some part of your body that needs it. Then it would have to be the case that you didn’t have enough to begin with, so this [antioxidant] made up for your deficiency. And then the last thing is, how would you measure that it did something?"

It's really tough to prove that the antioxidants in your morning goji berries, for example, are the reason you do or don't get heart disease 50 years from now.  

Because of all this, the USDA decided to shut down its online ORAC database back in 2012, writing that ORAC values were "routinely misused" by food and supplement companies.

This doesn't mean products that list ORAC scores are necessarily bad for you. On the contrary, foods with high ORAC scores are often very nutritious choices, cardiologist Joel Kahn, MD, another THI member, told INSIDER.

But you shouldn't let antioxidant-based marketing claims sway your food decisions. Don't spend more on a certain type of berry solely because it has a high ORAC score or the word "antioxidants" plastered all over the package. Just buy whatever berries you want to eat.

One thing is clear: Foods that contain lots of antioxidants are good for your health.

Most health authorities agree: Antioxidant supplements aren't worth your money, but antioxidant-rich foods definitely are. 

"Antioxidant-rich foods probably sound familiar because we've been telling you to eat those for a really long time," Gardner said. 

Fruits, vegetables, whole grains — these foods are all rich in antioxidants, but they also have healthful fiber and essential nutrients your body needs. Plus, a robust body of evidence says that they're beneficial for long-term health.

"People should get the majority of their antioxidants from brightly colored fresh fruits and vegetables," Kahn said. "There’s no doubt eating fruits and vegetables is a dose-related way to improve your health."