Most recent studies found that antioxidants in citrus fruit may protect chronic diseases caused by obesity.Lemon, lime, oranges, tangerine and other citrus fruits are good for everyone -- they contain plenty of vitamins and substances, such as antioxidants, that can help keep you healthy. Now scientists found one kind antioxidants in oranges, limes and lemons that may help fighting against the harmful effects of obesity in mice fed a Western high-fat foods.
Diabetes, heart disease and liver disease are increasing rapidly as more people pack on the kilos. But there’s a substance in citrus fruits called flavanones, which are antioxidants that help people to reduce the amount of oxidative stress in their body. The diseases linked to obesity are caused by oxidative stress and its related inflammation.
The scientists are releasing their studies at the 252nd National Meeting &Exposition of the American Chemical Society (ACS) today.
As people consume a fatty diet, their fat cells produce reactive oxygen species that damage cells. When fat cells become too large, which they do in obese individuals, they produce higher levels of reactive oxygen species that overwhelm the body, causing inflammation and disease.
Researchers say antioxidants found in fruits and vegetables, such as citrus flavanones, help protect reactive oxygen species and reduce oxidative stress in human and other animals that eat a high fat diet.
Those fruits and vegetables contain antioxidants called flavonoids, which are the largest group of phytonutrients, a type of plant chemicals with more than 6,000 types. Phytonutrients along with carotenoids are responsible for the vivid colors of fruits and vegetables.
There are several groups of flavonoids, including anthocyanidins, flavanols, flavones, flavanones and isoflavones. Flavanones,such as hesperidin, eriocitrin, and eriodictyol, are abundant in citrus fruits and have been associated with lowering oxidative stress in vitro and animal models.
Paula S. Ferreira, a graduate student with the research team says, "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.”
Chronic diseases in obese people are caused by of oxidative stress
More than one-third of all adults in the U.S. are obese, according to the U.S.Centers for Disease Control and Prevention. Being obese increases the risk of developing heart disease, liver disease and diabetes, most likely because of oxidative stress and inflammation, Ferreira says.
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.
Ferreira and colleagues aimed to observe the effects of citrus flavanones on mice with no genetic modifications 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, lime sand lemons. The flavanones they focused on were hesperidin, eriocitrin and eriodictyol. The mice were divided into few groups.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.
Cell damages in the liver and blood can be reduce with flavanones
The scientist team found that mice on the high fat died had 80 percent more cell damage markers in their blood and 57 percent in the liver compared to rodents fed a normal diet.
Again mice fed a high fat diet plus the three flavanones - hesperidin, eriocitrin and eriodictyol - had a reduction in cell damage markers compared to mice on a standard diet. Reductions in the liver ranged from 50 to 64 percent depending upon the flavanone given compared to those on a high fat diet alone.
As with the results in the liver, eriocitrin and eriodictyol reduced TBARS levels in the blood by 48 percent and 47 percent, respectively, in mice on the high-fat non-flavanone diet.
Researchers said the obese mice became healthier consuming citrus flavanones even though they did lose any weight.
"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."
Ferreiraadds, "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."
Next, the team will explore how best to administer these flavanones, whether in citrus juice, by consuming the fruit or developing a pill with these antioxidants. In addition, the team plans to conduct studies involving humans, Cesar says.
Researchers again said it’s possible that citrus could be beneficial to people who are not obese but eat a fatty, Western-style diet, she said. Ferreira said the best way to get flavanones is to drink them,like orange juice.
However future studies will explore the best ways to administer the flavanones comparing delivery through fruit juice, consuming fruits, or developing an antioxidant pill. The team also plans to move on from mouse studies to human studies.
Cesar also acknowledges funding from the Support Program for Scientific Development of the School of Pharmaceutical Sciences at UNESP and by Citrosuco, an orange juice production company in Matão, Sao Paulo,Brazil.