Antioxidants Found in Citrus Fruits Could Protect From Disease, Say Researchers

22 Aug 2016 --- A new study has revealed that obesity, heart disease, liver disease and diabetes could all be prevented by the consumption of citrus flavanones, a class of antioxidants found in citrus fruits.

With more than one-third of all adults in the US obese, the development of heart disease, liver disease and diabetes is higher than ever.

Paula S. Ferreira, a graduate student with the research team, thinks the development of disease is most likely because of oxidative stress and inflammation.

“When humans consume a high-fat diet, they accumulate fat in their bodies. Fat cells produce excessive reactive oxygen species, which can damage cells in a process called oxidative stress. The body can usually fight off the molecules with antioxidants. But obese patients have very enlarged fat cells, which can lead to even higher levels of reactive oxygen species that overwhelm the body's ability to counteract them.”

The researchers set out to observe the effects of the citrus antioxidants called flavanones for the first time on mice with no genetic modifications and that were fed a high-fat diet.

The team, at Universidade Estadual Paulista (UNESP) in Brazil, conducted an experiment with 50 mice, treating them with flavanones found in oranges, limes and lemons. The flavanones they focused on were hesperidin, eriocitrin and eriodictyol. For one month, researchers gave groups either a standard diet, a high-fat diet, a high-fat diet plus hesperidin, a high-fat diet plus eriocitrin or a high-fat diet plus eriodictyol.

The high-fat diet without the flavanones increased the levels of cell-damage markers by 80 percent in the blood and 57 percent in the liver compared to mice on a standard diet. 

However, hesperidin, eriocitrin and eriodictyol decreased the cell-damage markers levels in the liver by 50 percent, 57 percent and 64 percent, respectively, compared with mice fed a high-fat diet but not given flavanones. Eriocitrin and eriodictyol also reduced these levels in the blood by 48 percent and 47 percent.

In addition, mice treated with hesperidin and eriodictyol had reduced fat accumulation and damage in the liver.

"Our results indicate that in the future we can use citrus flavanones, a class of antioxidants, to prevent or delay chronic diseases caused by obesity in humans," said Ferreira.

"Our studies did not show any weight loss due to the citrus flavanones," says Thais B. Cesar, Ph.D., who leads the team. 

"However, even without helping the mice lose weight, they made them healthier with lower oxidative stress, less liver damage, lower blood lipids and lower blood glucose." 

Ferreira adds, "This study also suggests that consuming citrus fruits probably could have beneficial effects for people who are not obese, but have diets rich in fats, putting them at risk of developing cardiovascular disease, insulin resistance and abdominal obesity." 

The team plans to conduct studies involving humans, and will explore how best to administer the flavanones, whether in citrus juice, by consuming the fruit or developing a pill with these antioxidants.