A large segment of health-conscious Americans avoid foods that are deep fried, for fear that it may clog their arteries or lead to certain cancers. But countering these ideas, some recent studies show that some deep frying may actually provide health benefits.
One such study found that vegetables fried in olive oil actually carry health benefits missing in other cooked veggies. Researchers tested four different vegetables: potatoes, tomatoes, eggplants and pumpkins. They cooked each in four different ways:
- deep frying
- boiling in water
- boiling in water and oil
The researchers then analyzed the cooked veggies for certain health-related traits, including their levels of phenols, which protect plants against insects and other pests. Phenols also give these plants their color and flavor. For example, we have phenols to thank for the taste of raspberries and the spiciness of hot peppers.
But phenols may also carry health benefits. Some studies suggest that many phenols can fight cancer, but that's not universally accepted. Green tea, which many advocates mention, carries phenols.
What's more, many phenols also act as antioxidants, which means that they capture dangerous compounds in the body before these rogues can do any serious damage. For example, the phenol resveratrol is responsible for the antioxidant effects of grapes and red wine. However, there's also no conclusive evidence citing the benefits of antioxidants.
So the study's researchers found that the phenolic levels of boiled vegetables either stayed the same or decreased after cooking. Meanwhile, the deep fried and sautÃ©ed veggies' phenol content increased after cooking.
So what accounted for this phenol difference? The use of olive oil.
Olive oil carries such phenols as tyrosol and rutin. These and many other phenols in olive oils contain antioxidants that may play a role in the prevention of cancer and Type-2 diabetes.
When vegetables are deep fried or sautÃ©d using olive oil, they gain the antioxidants transferred from the olive oil. So while most foods lose their nutrients when deep fried, veggies actually gain nutrients when cooked in olive oil.
The antioxidants in olive oils aren t just good for our health, they also make olive oil one of the best choices when it comes to cooking and deep frying.
Antioxidants keep olive oil very stable in heat. According to a study reported by the Journal of Agricultural and Food Chemistry, after 36 hours of constant high heat olive oil maintain[s] most of its minor compounds and, therefore, most of its nutritional properties."
While the study found that deep fried veggies gain more nutrients than boiled veggies, they also found that deep frying increased the veggies' fat content more than did boiling. So with the addition of many more calories, those watching their weight would be wise to think twice about this kind of food preparation.
That said, the increased fat content may not be so bad when accounting for the nutrients gained. After all, humans need a certain amount of fat to survive. And we could all use some more phenols.