Popcorn: the snack with even higher antioxidant levels than fruits and vegetables

Popcorn’s reputation as a snack food that’s actually good for health popped up a few notches today as scientists reported that it contains more of the healthful antioxidant substances called “polyphenols” than fruits and vegetables. They spoke at the 243rd National Meeting & Exposition of the American Chemical Society (ACS), the world’s largest scientific society, being held in San Diego, USA this week.

Joe Vinson, Ph.D., a pioneer in analyzing healthful components in chocolate, nuts and other common foods, explained that the polyphenols are more concentrated in popcorn, which averages only about 4 percent water, while polyphenols are diluted in the 90 percent water that makes up many fruits and vegetables.

In another surprising finding, the researchers discovered that the hulls of the popcorn –– the part that everyone hates for its tendency to get caught in the teeth –– actually has the highest concentration of polyphenols and fiber.

“Those hulls deserve more respect,” said Vinson, who is with the University of Scranton in Pennsylvania. “They are nutritional gold nuggets.”

The overall findings led Vinson to declare, “Popcorn may be the perfect snack food. It’s the only snack that is 100 percent unprocessed whole grain. All other grains are processed and diluted with other ingredients, and although cereals are called “whole grain,” this simply means that over 51 percent of the weight of the product is whole grain. One serving of popcorn will provide more than 70 percent of the daily intake of whole grain. The average person only gets about half a serving of whole grains a day, and popcorn could fill that gap in a very pleasant way.”

Vinson cautioned, however, that the way people prepare and serve popcorn can quickly put a dent in its healthful image. Cook it in a potful of oil, slather on butter or the fake butter used in many movie theaters, pour on the salt; eat it as “kettle corn” cooked in oil and sugar — and popcorn can become a nutritional nightmare loaded with fat and calories.

“Air-popped popcorn has the lowest number of calories, of course,” Vinson said. “Microwave popcorn has twice as many calories as air-popped, and if you pop your own with oil, this has twice as many calories as air-popped popcorn. About 43 percent of microwave popcorn is fat, compared to 28 percent if you pop the corn in oil yourself.”

Likewise, Vinson pointed out that popcorn cannot replace fresh fruits and vegetables in a healthy diet. Fruits and vegetables contain vitamins and other nutrients that are critical for good health, but are missing from popcorn.

Vinson explained that the same concentration principle applies to dried fruit versus regular fruit, giving dried fruit a polyphenol edge. Previous studies found low concentrations of free polyphenols in popcorn, but Vinson’s team did the first study to calculate total polyphenols in popcorn. The amounts of these antioxidants were much higher than previously believed, he said. The levels of polyphenols rivaled those in nuts and were up to 15 times greater than whole-grain tortilla chips.

The new study found that the amount of polyphenols found in popcorn was up to 300 mg a serving compared to 114 mg for a serving of sweet corn and 160 mg for all fruits per serving. In addition, one serving of popcorn would provide 13 percent of an average intake of polyphenols a day per person in the U.S. Fruits provide 255 mg per day of polyphenols and vegetables provide 218 mg per day to the average U.S. diet.

Michael G. Coco, an undergraduate chemistry student at the University of Scranton who participated in the study, said he benefited in several ways.

“From working on this project with Dr. Vinson, I’ve gained experience and many insights in doing scientific research,” said Coco. “Besides the obvious things like learning how to use instrumentation and perform analyses, I’ve also learned that research is extremely satisfying, especially when you discover or think of something no one else has thought of.”

 

Powerful Antioxidant Resveratrol Prevents Metabolic Syndrome In Lab Tests

Researchers in the Faculty of Medicine & Dentistry at the University of Alberta have discovered that resveratrol, a powerful antioxidant found in common foods, prevents a syndrome in some offspring that could lead to later health issues such as diabetes.

Resveratrol is found in fruits, nuts and red wine, and has been shown to extend the lifespan of many species.

Human offspring that have trouble growing in the womb have an increased risk of developing metabolic problems later in life. But U of A medical researchers Jason Dyck and Sandra Davidge and their teams found that administering resveratrol to the young offspring of lab rats after weaning actually prevented the development of a metabolic syndrome, which is characterized by glucose intolerance, insulin resistance and higher deposits of abdominal fat.

Dyck and Davidge published their findings in a recent edition of the peer-reviewed journal Diabetes. Dyck is a researcher in the departments of Pediatrics and Pharmacology, while Davidge is a researcher in the departments of Obstetrics & Gynecology and Physiology. Both are also members of the Mazankowski Alberta Heart Institute, as well as the Women and Children’s Health Research Institute. Dyck and Davidge were co-senior authors of the study.

The study took advantage of the fact that “infancy is a potential window of opportunity to intervene and prevent the future development of metabolic diseases.” The researchers noted this is the first potential pharmacological treatment that may help babies that developed in a growth-restricted environment in the womb.

“There is a concept that in utero, there are genetic shifts that are occurring – reprogramming is occurring because of this strenuous environment babies are in, that allows them to recover very quickly after birth,” says Dyck.

“When babies are growth-restricted, they usually have a catch-up period after they are born where they catch up to non-growth-restricted groups. It might be that reprogramming that creates this kind of ‘thrifty’ phenotype, where they want to consume and store and get caught up.

“That reprogramming appears to make them more vulnerable to developing a host of metabolic problems.”

Earlier this year, Dyck and Davidge published another paper in Diabetes demonstrating that rat offspring not growing well in the womb had noticeable side effects from high-fat diets after birth – the rats deposited more fat in the abdominal area, developed glucose intolerance, more dramatic cases of insulin resistance and insulin resistance at earlier stages of life.

Dyck and Davidge are continuing their research in this area, examining whether treating the mother during pregnancy can prevent metabolic problems in rat offspring affected by intrauterine growth restriction.

Davidge is an Alberta Innovates-Health Solutions (AIHS) Scientist and a Canada Research Chair in Women’s Cardiovascular Health. Dyck is an AIHS Senior Scholar and the Director of the Cardiovascular Research Centre at the U of A.

 

Reference 

Dolinsky VW, Rueda-Clausen CF, Morton JS, Davidge ST, Dyck JR. Continued postnatal administration of resveratrol prevents diet-induced metabolic syndrome in rat offspring born growth restricted. Diabetes 2011; 60 (9): 2274-84.

 

Chocolate Is A ‘Super Fruit’

It is widely known that fruit contains antioxidants which may be beneficial to health. New research published in the open access journalChemistry Central Journal demonstrates that chocolate is a rich source of antioxidants and contains more polyphenols and flavanols than fruit juice.

When researchers at the Hershey Center for Health & Nutrition™ compared the antioxidant activity in cocoa powder and fruit powders they found that, gram per gram, there was more antioxidant capacity, and a greater total flavanol content, in the cocoa powder.

Similarly when they compared the amount of antioxidants, per serving, of dark chocolate, cocoa, hot chocolate mix and fruit juices they found that both dark chocolate and cocoa had a greater antioxidant capacity and a greater total flavanol, and polyphenol, content than the fruit juices. However hot chocolate, due to processing (alkalization) of the chocolate, contained little of any.

Dr Debra Miller, the senior author of the paper, says that, “Cacao seeds are a “Super Fruit” providing nutritive value beyond that of their macronutrient composition”. Which is great news for chocolate lovers.

 

Reference

Crozier SJ, Preston AG, Hurst JW, Payne MJ, Mann J, Hainly L, Miller DL. Cacao seeds are a “Super Fruit”: A comparative analysis of various fruit powders and products. Chemistry Central Journal 2011, 5: 5.

 

Antioxidant Spices Reduce Negative Effects Of High-Fat Meal

Eating a diet rich in spices, like turmeric and cinnamon, reduces the body’s negative responses to eating high-fat meals, according to Penn State researchers.

“Normally, when you eat a high-fat meal, you end up with high levels of triglycerides, a type of fat, in your blood,” said Sheila West, associate professor of biobehavioral health, Penn State, who led the study. “If this happens too frequently, or if triglyceride levels are raised too much, your risk of heart disease is increased. We found that adding spices to a high-fat meal reduced triglyceride response by about 30 percent, compared to a similar meal with no spices added.”

West and her colleagues prepared meals on two separate days for six men between the ages of 30 and 65 who were overweight, but otherwise healthy. The researchers added two tablespoons of culinary spices to each serving of the test meal, which consisted of chicken curry, Italian herb bread, and a cinnamon biscuit. The control meal was identical, except that spices were not included. The team drew blood from the participants every 30 minutes for three hours. They reported their findings in the current issue of the Journal of Nutrition.

“In the spiced meal, we used rosemary, oregano, cinnamon, turmeric, black pepper, cloves, garlic powder and paprika,” said Ann Skulas-Ray, postdoctoral fellow. “We selected these spices because they had potent antioxidant activity previously under controlled conditions in the lab.”

When the meal contained a blend of antioxidant spices, antioxidant activity in the blood was increased by 13 percent and insulin response decreased by about 20 percent.

According to West, many scientists think that oxidative stress contributes to heart disease, arthritis and diabetes. “Antioxidants, like spices, may be important in reducing oxidative stress and thus reducing the risk of chronic disease,” she said, adding that the spice dose they used provided the equivalent amount of antioxidants contained in 5 ounces of red wine or 1.4 ounces of dark chocolate.

Skulas-Ray noted that adding two tablespoons of spices to meals did not cause stomach upset in the participants. “They enjoyed the food and had no gastrointestinal problems,” she said. But, she added, “The participants were notified ahead of time that they would be eating highly spiced foods and they were willing to do so.”

In the future, West plans to investigate whether she can get the same results by adding smaller doses of spices to meals.

 

Antioxidants Of Growing Interest To Address Infertility, Erectile Dysfunction

A growing body of evidence suggests that antioxidants may have significant value in addressing infertility issues in both women and men, including erectile dysfunction, and researchers say that large, specific clinical studies are merited to determine how much they could help. The study this story is based on is available from ScholarsArchive@OSU: http://bit.ly/nNir7E

 

CORVALLIS, Ore. – A growing body of evidence suggests that antioxidants may have significant value in addressing infertility issues in both women and men, including erectile dysfunction, and researchers say that large, specific clinical studies are merited to determine how much they could help.

A new analysis, published online in the journal Pharmacological Research, noted that previous studies on the potential for antioxidants to help address this serious and growing problem have been inconclusive, but that other data indicates nutritional therapies may have significant potential.

The researchers also observed that infertility problems are often an early indicator of other degenerative disease issues such as atherosclerosis, high blood pressure and congestive heart failure. The same approaches that may help treat infertility could also be of value to head off those problems, they said.

The findings were made by Tory Hagen, in the Linus Pauling Institute at Oregon State University, and Francesco Visioli, lead author of the study at the Madrid Institute for Advanced Studies in Spain.

“If oxidative stress is an underlying factor causing infertility, which we think the evidence points to, we should be able to do something about it,” said Hagen, the Jamieson Chair of Healthspan Research in the Linus Pauling Institute. “This might help prevent other critical health problems as well, at an early stage when nutritional therapies often work best.”

The results from early research have been equivocal, Hagen said, but that may be because they were too small or did not focus on antioxidants. Laboratory and in-vitro studies have been very promising, especially with some newer antioxidants such as lipoic acid that have received much less attention.

“The jury is still out on this,” Hagen said. “But the problem is huge, and the data from laboratory studies is very robust, it all fits. There is evidence this might work, and the potential benefits could be enormous.”

The researchers from Oregon and Spain point, in particular, to inadequate production of nitric oxide, an agent that relaxes and dilates blood vessels. This is often caused, in turn, by free radicals that destroy nitric oxide and reduce its function. Antioxidants can help control free radicals. Some existing medical treatments for erectile dysfunction work, in part, by increasing production of nitric oxide.

Aging, which is often associated with erectile dysfunction problems, is also a time when nitric oxide synthesis begins to falter. And infertility problems in general are increasing, scientists say, as more people delay having children until older ages.

“Infertility is multifactorial and we still don’t know the precise nature of this phenomenon,” Visioli said.

If new approaches were developed successfully, the researchers said, they might help treat erectile dysfunction in men, egg implantation and endometriosis in women, and reduce the often serious and sometimes fatal condition of pre-eclampsia in pregnancy. The quality and health of semen and eggs might be improved.

As many as 50 percent of conceptions fail and about 20 percent of clinical pregnancies end in miscarriage, the researchers noted in their report. Both male and female reproductive dysfunction is believed to contribute to this high level of reproductive failure, they said, but few real causes have been identified.

“Some people and physicians are already using antioxidants to help with fertility problems, but we don’t have the real scientific evidence yet to prove its efficacy,” Hagen said. “It’s time to change that.”

Some commonly used antioxidants, such as vitamins C and E, could help, Hagen said. But others, such as lipoic acid, are a little more cutting-edge and set up a biological chain reaction that has a more sustained impact on vasomotor function and health.

Polyphenols, the phytochemicals that often give vegetables their intense color and are also found in chocolate and tea, are also of considerable interest. But many claims are being made and products marketed, the researchers said, before the appropriate science is completed – actions that have actually delayed doing the proper studies.

“There’s a large market of plant-based supplements that requires hard data,” Visioli said. “Most claims are not backed by scientific evidence and human trials. We still need to obtain proof of efficacy before people invest money and hope in preparations of doubtful efficacy.”

About the Linus Pauling Institute: The Linus Pauling Institute at OSU is a world leader in the study of micronutrients and their role in promoting optimum health or preventing and treating disease. Major areas of research include heart disease, cancer, aging and neurodegenerative disease.