Thursday, March 19, 2015

Health Benefits of Peaches, Plums and Prunes

Peach extract slows breast cancer growth and spread
Washington State University food scientist and colleagues at Texas A&M have found that compounds in peaches can inhibit the growth of breast cancer cells and their ability to spread.

Writing in the Journal of Nutritional Biochemistry, the researchers say the compounds could be a novel addition to therapies that reduce the risk of metastasis, the primary killer in breast and many other cancers. The compounds could be given as an extract or, judging from the doses given mice in the study, two to three peaches a day.

"I would do three peaches a day," said Giuliana Noratto, WSU assistant professor of food science.

Study expands to other foods

The study also underscores the value of good nutrition in preventing cancer, she said.

"Having enough fruits and vegetables that can provide these compounds in our diet, we might have a similar preventive effect," said Noratto. She is now looking at compounds in wheat, barley, quinoa, apples and dairy products that could have a role in preventing obesity-related diseases.

The research was part of her doctoral work at Texas A&M with plant breeder David Byrne, food scientist Luis Cisneros-Zevallos and toxicologist Weston Porter.

Medicinal plant tradition

She was drawn to the research after doing work on the antioxidant activity of root plants in her native Peru.

"We have a huge tradition of medicinal plants," she said. "We are great believers that you can cure yourself by having a good diet and a good supply of medicinal plants."

In 2009, Noratto and her colleagues at Texas A&M published a study showing that peach and plum extracts suppressed breast cancer cells cultured in petri dishes. For the new study, the researchers implanted breast cancers cells beneath the skin of mice. The technique, called a xenograft, is often used to look at the growth of breast cancer cells in a living animal, mimicking the interactions by which tumors form and progress.

Metastasis inhibited too

After giving the cells a week to establish, the researchers fed the mice varying doses of peach polyphenols, compounds that help plants ward off the damaging effects of the sun's ultraviolet radiation.

"There are several studies showing that these compounds act as antioxidants and can therefore protect DNA against damage that can produce cancer," said Noratto, the first author of both studies. Other researchers have seen that phenomenon, Noratto said, but she and her colleagues wanted to know if the compounds might start a cascade of signals that could induce the cancer cells to commit suicide.

"We didn't even think about metastasis at that time," she said. "The surprise was we analyzed lungs and beside the fact that the peach compounds inhibited the growth of the tumor, they also inhibited the metastasis levels on the lungs."

Moreover, after 12 days the researchers saw that mice fed with high levels of polyphenols had tumors that grew less and without much of the blood vessel formation that can help cancer cells spread to other parts of the body. The tumors in those mice also had less evidence of enzymes involved in the spread and invasion of cancer.

The doses given the mice, if scaled up to a 132-pound person, could be supplied by two to three peaches a day or a dietary supplement of peach polyphenol extract powder.

Peaches, plums, nectarines fight obesity, diabetes, heart disease

Peaches, plums and nectarines have bioactive compounds that can potentially fight-off obesity-related diabetes and cardiovascular disease, according to new (June, 2012) studies by Texas AgriLife Research.

The study, presented at the American Chemical Society in Philadelphia showed that the compounds in stone fruits could be a weapon against "metabolic syndrome," in which obesity and inflammation lead to serious health issues, according to Dr. Luis Cisneros-Zevallos, AgriLife Research food scientist.

"In recent years obesity has become a major concern in society due to the health problems associated to it," said Cisneros-Zevallos, who also is an associate professor at Texas A&M University. "In the U.S., statistics show that around 30 percent of the population is overweight or obese, and these cases are increasing every year in alarming numbers."

While he acknowledged that lifestyle, genetic predisposition and diet play a major role in one's tendency toward obesity, "the major concern about obesity is the associated disease known as metabolic syndrome.

"Our studies have shown that stone fruits – peaches, plums and nectarines – have bioactive compounds that can potentially fight the syndrome," Cisneros-Zevallos said. "Our work indicates that phenolic compounds present in these fruits have anti-obesity, anti-inflammatory and anti-diabetic properties in different cell lines and may also reduce the oxidation of bad cholesterol LDL which is associated to cardiovascular disease."

What is unique to these fruits, he said, is that their mixture of the bioactive compounds work simultaneously within the different components of the disease.

"Our work shows that the four major phenolic groups – anthocyanins, clorogenic acids, quercetin derivatives and catechins – work on different cells – fat cells, macrophages and vascular endothelial cells," he explained. "They modulate different expressions of genes and proteins depending on the type of compound.

"However, at the same time, all of them are working simultaneously in different fronts against the components of the disease, including obesity, inflammation, diabetes and cardiovascular disease," he explained.

Cisneros-Zevallos said this is believed to be the first time that "bioactive compounds of a fruit have been shown to potentially work in different fronts against a disease."

"Each of these stone fruits contain similar phenolic groups but in differing proportions so all of them are a good source of health promoting compounds and may complement each other," he said, adding that his team plans to continue studying the role of each type of compound on the molecular mechanisms and confirm the work with mice studies.

Peaches, plums induce deliciously promising death of breast cancer cells

Breast cancer cells - even the most aggressive type - died after treatments with peach and plum extracts in lab tests at Texas AgriLife Research recently, and scientists say the results are deliciously promising. Not only did the cancerous cells keel over, but the normal cells were not harmed in the process.

AgriLife Research scientists say two phenolic compounds are responsible for the cancer cell deaths in the study, which was published in the Journal of Agriculture and Food Chemistry. The phenols are organic compounds that occur in fruits. They are slightly acidic and may be associated with traits such as aroma, taste or color.

"It was a differential effect which is what you're looking for because in current cancer treatment with chemotherapy, the substance kills all cells, so it is really tough on the body," said Dr. David Byrne, AgriLife Research plant breeder who studies stone fruit. "Here, there is a five-fold difference in the toxic intensity. You can put it at a level where it will kill the cancer cells - the very aggressive ones - and not the normal ones."

Byrne and Dr. Luis Cisneros-Zevallos originally studied the antioxidants and phytonutrients in plums and found them to match or exceed the blueberry which had been considered superior to other fruits in those categories.

"The following step was to choose some of these high antioxidant commercial varieties and study their anticancer properties," Cisneros-Zevallos said. "And we chose breast cancer as the target because it's one of the cancers with highest incidence among women. So it is of big concern."

According to the National Cancer Institute, there were 192,370 new cases of breast cancer in females and 1,910 cases in males in 2009. That year, 40,170 women and 440 men died from breast cancer. The World Health Organization reports that breast cancer accounts for 16 percent of the cancer deaths of women globally.

Cisneros-Zevallos, an AgriLife Research food scientist, said the team compared normal cells to two types of breast cancer, including the most aggressive type. The cells were treated with an extract from two commercial varieties, the "Rich Lady" peach and the "Black Splendor" plum.

"These extracts killed the cancer cells but not the normal cells," Cisneros-Zevallos said.

A closer look at the extracts determined that two specific phenolic acid components - chlorogenic and neochlorogenic - were responsible for killing the cancer cells while not affecting the normal cells, Cisneros-Zevallos said.

The two compounds are very common in fruits, the researchers said, but the stone fruits such as plums and peaches have especially high levels.

"So this is very, very attractive from the point of view of being an alternative to typical chemotherapy which kills normal cells along with cancerous ones," Byrne added.

The team said laboratory tests also confirmed that the compounds prevented cancer from growing in animals given the compounds.

Byrne plans to examine more fully the lines of the varieties that were tested to see how these compounds might be incorporated into his research of breeding plums and peaches. Cisneros-Zevallos will continue testing these extracts and compounds in different types of cancer and conduct further studies of the molecular mechanisms involved.

Eating prunes helps prevent fractures and osteoporosis
When it comes to improving bone health in postmenopausal women — and people of all ages, actually — a Florida State University researcher has found a simple, proactive solution to help prevent fractures and osteoporosis: eating dried plums.

"Over my career, I have tested numerous fruits, including figs, dates, strawberries and raisins, and none of them come anywhere close to having the effect on bone density that dried plums, or prunes, have," said Bahram H. Arjmandi, Florida State's Margaret A. Sitton Professor and chairman of the Department of Nutrition, Food and Exercise Sciences in the College of Human Sciences. "All fruits and vegetables have a positive effect on nutrition, but in terms of bone health, this particular food is exceptional."

Arjmandi and a group of researchers from Florida State and Oklahoma State University tested two groups of postmenopausal women. Over a 12-month period, the first group, consisting of 55 women, was instructed to consume 100 grams of dried plums (about 10 prunes) each day, while the second — a comparative control group of 45 women — was told to consume 100 grams of dried apples. All of the study's participants also received daily doses of calcium (500 milligrams) and vitamin D (400 international units).

The group that consumed dried plums had significantly higher bone mineral density in the ulna (one of two long bones in the forearm) and spine, in comparison with the group that ate dried apples. This, according to Arjmandi, was due in part to the ability of dried plums to suppress the rate of bone resorption, or the breakdown of bone, which tends to exceed the rate of new bone growth as people age.

The group's research, "Comparative Effects of Dried Plum and Dried Apple on Bone in Post Menopausal Women was published August, 2011 in the British Journal of Nutrition. Arjmandi conducted the research with his graduate students Shirin Hooshmand, Sheau C. Chai and Raz L. Saadat of the College of Human Sciences; Dr. Kenneth Brummel-Smith, Florida State's Charlotte Edwards Maguire Professor and chairman of the Department of Geriatrics in the College of Medicine; and Oklahoma State University statistics Professor Mark E. Payton.

In the United States, about 8 million women have osteoporosis because of the sudden cessation of ovarian hormone production at the onset of menopause. What's more, about 2 million men also have osteoporosis.

"In the first five to seven postmenopausal years, women are at risk of losing bone at a rate of 3 to 5 percent per year," Arjmandi said. "However, osteoporosis is not exclusive to women and, indeed, around the age of 65, men start losing bone with the same rapidity as women."

Arjmandi encourages people who are interested in maintaining or improving their bone health to take note of the extraordinarily positive effect that dried plums have on bone density.

"Don't wait until you get a fracture or you are diagnosed with osteoporosis and have to have prescribed medicine," Arjmandi said. "Do something meaningful and practical beforehand. People could start eating two to three dried plums per day and increase gradually to perhaps six to 10 per day. Prunes can be eaten in all forms and can be included in a variety of recipes."

The Bone-Boosting Benefits of Dried Plums

Fifty-seven million Americans suffer from low bone density or osteoporosis, a disease which causes bones to become so weak and brittle that even a minor fall or other stresses may cause fractures.(1) A study published in the British Journal of Nutrition in July 2014 examined the mechanism of the bone-protective properties of an unlikely source—California dried plums.(2)

To further understand the mechanism by which dried plums (prunes) improve bone health, researchers from San Diego State University and Florida State University used data collected from a previous 12-month clinical trial that compared the bone-protective effects of dried plums and dried apples.(3) Results from this clinical trial confirmed the bone-protective properties of dried plums, and several animal studies have also supported this finding. However, the mechanisms by which dried plums impart their bone-protective properties remain unclear.

“While it is difficult to identify the exact mechanism behind dried plums’ positive effect on bones, this study identified three potential pathways for the mechanism behind the effect of dried plums on bone resorption and bone formation,” explains Dr. Shirin Hooshmand, PhD, Assistant Professor Department of Exercise and Nutritional Sciences at San Diego State University. “We are excited to continue to apply the results of this study to future research that may help us to determine the exact link between dried plums and healthy bones.”

During the original 12-month clinical trial, which was published in 2011 in the British Journal of Nutrition, 160 osteopenic, postmenopausal women were randomly assigned to eat either 100 grams dried plums (about 10 dried plums) daily or 75 grams dried apple daily. Each participant also received 500 milligrams of calcium plus a daily vitamin D supplement (400 international units). The results indicated that the group that consumed dried plums had significantly higher bone mineral density in the ulna (one of two long bones in the forearm) and spine, in comparison with the group that ate dried apples.

This, according to study author and researcher Dr. Bahram H. Arjmandi, PhD, RD, Florida State University’s Margaret A. Sitton Professor of the Department of Nutrition, Food and Exercise Sciences and Director of the Center for Advancing Exercise and Nutrition Research on Aging (CAENRA) in the College of Human Sciences, was due, in part, to the ability of dried plums to suppress the rate of bone resorption, or the breakdown of bone, which tends to exceed the rate of new bone growth as people age.

“Nature has created dried plums to be unique in nutrient composition. They really are the whole package,” explains Dr. Arjmandi. “In more than 15 years of research, I have never seen a fruit like dried plums. Research suggests that dried plums may actually help to regenerate bone in people who have experienced bone loss. This is a serious issue for men and women alike, and dried plums continue to show promising results in the prevention and reversal of bone loss.”

Results of additional animal studies which measured effects on bone mineral density are consistent, showing strong supporting evidence of an effect of dried plums on bone mineral density and/or markers of bone turnover. Collectively, both the human and animal studies indicate that adding dried plums to the diet may be an effective way to help support healthy bones.

Research also suggests dried plums may support heart health and digestive health and may improve satiety:

•Dried plums help manage weight through improved satiety, perhaps by producing lower glucose and/or appetite-regulating hormone concentrations. (4)
•Dried plums reduce LDL cholesterol in both animals and humans. (5)

•Dried plums promote digestive health and are palatable and more effective than psyllium for the treatment of mild to moderate constipation, and should be considered as first-line therapy. (6)

•Dried plums are considered a low-glycemic index (GI) food, which means they are likely more satiating than high-GI foods and do not cause a large rise and fall in blood glucose levels and insulin response after a meal.(7)

1. Learn About Osteoporosis.” National Osteoporosis Foundation. Web. 15 October 2013.
2. British Journal of Nutrition / Volume 112 / Issue 01 / July 2014, pp 55 - 60
3. British Journal of Nutrition (2011), 106, 923–930.
4. Furchner-Evanson A, Petrisko Y, Howarth L, Nemoseck T, Kern M. Type of snack influences satiety responses in adult women. Appetite. 2010;54:564–569.
5. Gallaher CM, Gallaher DD. Dried plums (prunes) reduce atherosclerosis lesion area in apolipoprotein E-deficient mice. British Journal of Nutrition. 2009;101(2):233–239.
6. Attaluri A, Donahoe R, Valestin J, Brown K, Rao SS. Randomised clinical trial: dried plums (prunes) vs. psyllium for constipation. Alimentary Pharmacology and Therapeutics. 2011;33:822–828.
7. Foster-Powell, K., Holt, S.H.A., Brand-Miller, J.C. International table of glycemic index and glycemic load values. The American Journal of Clinical Nutrition. 2002.76:5-56.

Eating prunes can help weight loss
Research by the University of Liverpool has found that eating prunes as part of a weight control diet can improve weight loss.

Consumption of dried fruit is not readily recommended during weight loss despite evidence it enhances feelings of fullness.

However, a study by the University's Institute of Psychology, Health and Society of 100 overweight and obese low fibre consumers tested whether eating prunes as part of a weight loss diet helped or hindered weight control over a 12-week period.

It also examined if low fibre consumers could tolerate eating substantial numbers of prunes in their diet, and if eating prunes had a beneficial effect on appetite.

To assess the effects of prunes on weight and appetite, participants in the study were divided into two groups – those who ate prunes every day (140g a day for women and 171g a day for men) and those who were given advice on healthy snacks over the period of active weight loss.

The researchers found that members of the group which ate prunes as part of a healthy life-style diet lost 2kg in weight and shed 2.5cm off their waists. However, the people in the group which was given advice on healthy snacks lost only 1.5kg in weight and 1.7cm from their waists.

The study also found that the prune eaters experienced greater weight loss during the last four weeks of the study. After week eight, participants showed increased feelings of fullness in the prune group. Moreover, despite the high daily doses, prunes were well tolerated.

Liverpool psychologist, Dr Jo Harrold who led the research, said: "These are the first data to demonstrate both weight loss and no negative side effects when consuming prunes as part of a weight management diet. Indeed in the long term they may be beneficial to dieters by tackling hunger and satisfying appetite; a major challenge when you are trying to maintain weight loss."

Professor Jason Halford, Professor of Experimental Psychology and Director of the University's Human Ingestive Behaviour Laboratory, added: "Maintaining a healthy diet is challenging. Along with fresh fruit and vegetables, dried fruit can provide a useful and convenient addition to the diet, especially as controlling appetite during dieting can be tough."

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