Monday, March 23, 2015

Health Benefits of Various Fruits: Avocados, Bananas, Cherries, Cranberries, Mangos, Pomegranates, Dates


Avocados lower bad cholesterol

Adding an avocado to your daily diet may help lower bad cholesterol, in turn reducing risk for heart disease, according to health researchers.

Avocados are known to be a nutrient-dense food, high in monounsaturated fatty acids. Previous studies have suggested that avocados are a cholesterol-lowering food, but this is the first study -- to the researchers' knowledge -- to look at health implications of avocados beyond monounsaturated fatty acids.

"Including one avocado each day as part of a moderate-fat, cholesterol-lowering diet compared to a comparable moderate-fat diet without an avocado provides additional LDL (low-density lipoproteins) lowering affects, which benefit CVD risk," said Penny M. Kris-Etherton, Distinguished Professor of Nutrition.

Kris-Etherton and colleagues tested three different diets, all designed to lower cholesterol: a lower-fat diet, consisting of 24 percent fat, and two moderate fat diets, with 34 percent fat. The moderate fat diets were nearly identical, however one diet incorporated one Hass avocado every day while the other used a comparable amount of high oleic acid oils -- such as olive oil -- to match the fatty acid content of one avocado. Hass avocados are the smaller, darker variety with bumpy green skin and have a higher nutrient content than Florida avocados, which are larger, and have smoother skin and a higher water content.

The researchers tested the diets with 45 healthy, overweight adults between the ages of 21 and 70. Compared to the participants' baseline measurements, all three diets significantly lowered LDL -- also known as bad cholesterol -- as well as total cholesterol. However, participants experienced an even greater reduction in LDL and total cholesterol while on the avocado diet, compared to the other two diets, the researchers report today (Jan. 7) in the Journal of the American Heart Association.

The avocado diet decreased bad cholesterol by 13.5 mg/dL, while LDL was decreased by 8.3 mg/dL on the moderate-fat diet and by 7.4 mg/dL on the low-fat diet.

All participants followed each of the three diets for five weeks. They were given a two-week break in between each diet. Blood samples were taken at the beginning and end of each study period. Subjects were randomly assigned the order in which they received each diet.

"This was a controlled feeding study, but that is not the real world -- so it is more of a proof-of-concept investigation," said Kris-Etherton. "We need to focus on getting people to eat a healthy diet that includes avocados and other food sources of better fats."

She pointed out that much of the U.S. population doesn't know how to use or prepare avocados, with the exception of guacamole. However, guacamole is usually eaten with corn chips, which are high in both sodium and calories.

"People should start thinking about eating avocados in new ways," said Kris-Etherton. "I think using it as a condiment is a great way to incorporate avocados into meals -- for instance, putting a slice or two on a sandwich or using chopped avocado in a salad or to season vegetables."

Kris-Etherton and colleagues note that further research will need to be conducted with a larger and more diverse study sample and to explore further how high-density lipoproteins -- good cholesterol -- might be affected by a diet that includes avocados.

Avocado Eaten With A Burger May Help Neutralize Interleukin-6

In November 2012, a study conducted by researchers at the University of California, Los Angeles (UCLA), Hass Avocado Modulates Postprandial Vascular Reactivity and Postprandial Inflammatory Responses to a Hamburger Meal in Healthy Volunteers, was published in the journal Food and Function.

This UCLA pilot studyi on 11 healthy men (18-35 years old,) on two separate occasions, found that eating one-half of a fresh medium Hass avocado with a burger (90 percent lean), rather than eating a burger alone, may curb the production of compounds that contribute to inflammation. Inflammation is a risk factor that may be associated with heart disease.ii

Specifically, the pilot study of 11 healthy men suggests that fresh Hass avocado, when eaten with a burger may neutralize Interleukin-6 (IL-6) - a protein that is a measure of inflammation - compared to eating a burger without fresh avocado.i The researchers observed a significant peak (approximately a 70 percent increase), of IL-6 four hours after the plain burger was eaten, but less effect on IL-6 (approximately a 40 percent increase) over the same time period when fresh avocado was eaten with the burger.i Additionally, the study found that when fresh Hass avocado was eaten with the burger it did not increase triglyceride levels beyond what was observed after eating the burger alone, despite the extra calories and fat from the fresh avocado.i Elevated triglyceride levelsiii are associated with heart disease.

The pilot study also reported that the difference in peripheral arterial blood flow (the movement of blood to different parts of the body, as measured by PAT), a predictor of vascular health, after eating the hamburger meal compared to the hamburger-fresh avocado meal was approaching statistical significance (P=.052). PAT scores significantly decreased (signifying reduced blood flow) only after the plain burger was eaten (approximately a 27 percent drop, on average) compared to a burger with fresh avocado (approximately a 4 percent drop, on average, signifying less reduction in blood flow).i This suggests the addition of the fresh avocado may have mitigated a larger reduction in blood flow. However, additional studies are needed.

These are initial findings from a single study of 11 healthy men that provide promising clues and a basis for future research to determine whether avocados can play a role in the areas of vascular health and heart health. "This study supports the hypothesis that fresh Hass avocado, may help support normal vascular function, which is important for heart health," said David Heber, MD, PhD, primary investigator of the study. "After eating a burger with one-half of a fresh medium Hass avocado, some of the after-meal effects observed after eating the plain burger, specifically inflammation and narrowing blood vessels, were reduced within hours, and triglycerides did not increase beyond what was observed after eating the burger alone.

Bananas Are as Beneficial as Sports Drinks

Bananas have long been a favorite source of energy for endurance and recreational athletes. Bananas are a rich source of potassium and other nutrients, and are easy for cyclists, runners or hikers to carry.

Research conducted at Appalachian State University’s Human Performance Lab in the Kannapolis-based North Carolina Research Campus (NCRC) has revealed additional benefits.

“We wanted to see which was more beneficial when consumed during intense cycling – bananas or a carbohydrate sports drink,” said Dr. David C. Nieman, director of the human performance lab and a member of the College of Health Sciences faculty at Appalachian.

“We found that not only was performance the same whether bananas or sports drinks were consumed, there were several advantages to consuming bananas,” he said.

The bananas provided the cyclists with antioxidants not found in sports drinks as well as a greater nutritional boost, including fiber, potassium and Vitamin B6, the study showed. In addition, bananas have a healthier blend of sugars than sports drinks.

The study, funded by Dole Foods, has been published in the peer-reviewed online journal PLoS ONE published by the nonprofit Public Library of Science (May 17, 2012 10.1371/journal.pone.0037479.

For the study, trained cyclists consumed either a cup of carbohydrate drink or half a banana every 15 minutes during a 75-kilometer simulated road race lasting 2.5 to 3 hours. Blood samples taken from the cyclists before and after the exercise were analyzed at the NCRC Metabolomics Laboratory for more than 100 metabolites – molecules associated with metabolism.

“Bananas come prepackaged with fiber, nutrients and antioxidants,” said Nieman, adding the research translates to any exercise.

“The mode of exercise is not the issue. I think there are a lot of athletes who don’t like the thought of drinking carbohydrate sports drinks, which are essentially flavored sugar water,” he said. “This type of research shows that you can have healthier carbohydrate sources before and after exercise that will support athletic performance just as well as a sports drink,” Nieman said.

Bananas Vs. Asthma

Going bananas may help kids breathe easier. Children who ate just one banana a day had a 34% less chance of developing asthmatic symptoms, according to new British research.

The Imperial College of London collected dietary information from 2,640 children, ages 5 to 10, and found that banana-eaters were one-third less likely to encounter breathing problems like wheezing. Children who drank apple juice daily experienced a 47% reduction. Other research suggests that children with low fiber intake are more vulnerable to the respiratory problems associated with secondhand smoke. The pineapple enzyme, bromelain, also appeared to reduce the inflammation associated with asthma in one animal trial.

These results offer yet more proof of the potential of food to affect asthma symptoms for better...or for worse. As previously reported in this space, kids who eat even one burger a week are more likely to suffer from asthma

Banana Bonus: Early banana consumption may also be associated with lower risk of childhood leukemia. Bananas' fiber, potassium, vitamin C and B6 content support heart health. Bananas also contain tryptophan,an amino acid which may play a role in preserving your memory and boosting your mood.

Cherries Lower Risk Of Gout Attacks By 35%

A new study found that patients with gout who consumed cherries over a two-day period showed a 35% lower risk of gout attacks compared to those who did not eat the fruit. Findings from this case-crossover study published in Arthritis & Rheumatism, (September 2012,) a journal of the American College of Rheumatology (ACR), also suggest that risk of gout flares was 75% lower when cherry intake was combined with the uric-acid reducing drug, allopurinol, than in periods without exposure to cherries or treatment.

Previous research reports that 8.3 million adults in the U.S. suffer with gout, an inflammatory arthritis triggered by a crystallization of uric acid within the joints that causes excruciating pain and swelling. While there are many treatment options available, gout patients continue to be burdened by recurrent gout attacks, prompting patients and investigators to seek other preventive options such as cherries. Prior studies suggest that cherry products have urate-lowering effects and anti-inflammatory properties, and thus may have the potential to reduce gout pain. However, no study has yet to assess whether cherry consumption could lower risk of gout attacks.

For the present study, lead author Dr. Yuqing Zhang, Professor of Medicine and Public Health at Boston University and colleagues recruited 633 gout patients who were followed online for one year. Participants were asked about the date of gout onset, symptoms, medications and risk factors, including cherry and cherry extract intake in the two days prior to the gout attack. A cherry serving was one half cup or 10 to 12 cherries.

Participants had a mean age of 54 years, with 88% being white and 78% of subjects were male. Of those subjects with some form of cherry intake, 35% ate fresh cherries, 2% ingested cherry extract, and 5% consumed both fresh cherry fruit and cherry extract. Researchers documented 1,247 gout attacks during the one-year follow-up period, with 92% occurring in the joint at the base of the big toe.

"Our findings indicate that consuming cherries or cherry extract lowers the risk of gout attack," said Dr. Zhang. "The gout flare risk continued to decrease with increasing cherry consumption, up to three servings over two days." The authors found that further cherry intake did not provide any additional benefit. However, the protective effect of cherry intake persisted after taking into account patients' sex, body mass (obesity), purine intake, along with use of alcohol, diuretics and anti-gout medications.

In their editorial, also published in Arthritis & Rheumatism, Dr. Allan Gelber from Johns Hopkins University School of Medicine in Baltimore, Md. and Dr. Daniel Solomon from Brigham and Women's Hospital and Harvard University Medical School in Boston, Mass. highlight the importance of the study by Zhang et al. as it focuses on dietary intake and risk of recurrent gout attacks. While the current findings are promising, Gelber and Solomon "would not advise that patients who suffer from gout attacks abandon standard therapies." Both the editorial and study authors concur that randomized clinical trials are necessary to confirm that consumption of cherry products could prevent gout attacks.

Cranberries have heart health, urinary and gastrointestinal tract and other metabolic benefits

Cranberries are more than a holiday favorite, given their remarkable nutritional and health benefits. A new research review published November 2013 in the international journal Advances in Nutrition provides reasons why these tiny berries can be front and center and not just a side dish. The review authors conclude that cranberries provide unique bioactive compounds that may help reduce the incidence of certain infections, improve heart health and temper inflammation.

Ten worldwide experts in cranberry and health research contributed to the article, including scientists and medical experts from Tufts University, Pennsylvania State University, Boston University, Rutgers University, French National Institute for Agricultural Research, University of East Anglia in the United Kingdom and Heinrich-Heine-University in Germany. The authors included more than 150 published research studies to create the most thorough and up-to-date review of the cranberry nutrition and human health research.

"Hundreds of studies show that the bioactive compounds found in cranberries improve health," said lead author Jeffrey Blumberg, PhD, FASN, FACN, CNS, Director of the Antioxidants Research Laboratory and Professor in the Friedman School of Nutrition Science and Policy at Tufts University. "For example, the polyphenols found in cranberries have been shown to promote a healthy urinary tract and exert protective benefits for cardiovascular disease and other chronic conditions."

Based on the totality of the published cranberry research, the authors concluded that the cranberry fruit is truly special because of the A-type proanthocyanidins (a polyphenol from the flavanol family), in contrast to the B-type proanthocyanidins present in most other types of berries and fruit.

The A-type proanthocyanidins appear to provide the anti-adhesion benefits that help protect against urinary tract infections (UTI), which affect more than 15 million U.S. women each year. They present evidence suggesting that cranberries may also reduce the recurrence of UTIs – an important approach for relying less on antibiotic treatment for the condition.

The authors also cite data that shows the cranberry may improve cardiovascular health by improving blood cholesterol levels and lowering blood pressure, inflammation and oxidative stress. Cranberries have been shown to help support endothelial function and reduce arterial stiffness. Together, these benefits may promote overall health and functioning of blood vessels to help slow the progression of atherogenesis and plaque formation, which can lead to heart attacks and stroke.

Need Fruit? Eat More Cranberries

While all fruit contributes necessary vitamins and minerals to the diet, berry fruits offer a particularly rich source of health-promoting polyphenols. Because of their tart taste and very low natural sugar content, sugar is often added to cranberry products for palatability. Even with added sugar, cranberry products typically have a comparable amount of sugar to other unsweetened fruit juices and dried fruit products. Additionally, the 2010 Dietary Guidelines for Americans asserts that the best use of calories from added sweeteners is for improving the palatability of nutrient-rich foods, as is the case when adding sugar to cranberries. As an additional option, non-nutritive sweeteners are used to produce low calorie versions of cranberry products. Americans can help increase their fruit intake by incorporating cranberries and cranberry products into their diet and there is no need to wait for the holidays – cranberries can be enjoyed year round – fresh, frozen, dried, or in a juice or sauce.

New study: Emerging research indicates mangos may lower blood sugar in obese adults

Research published in the journal Nutrition and Metabolic Insights found that regular consumption of mango by obese adults may lower blood sugar levels and does not negatively impact body weight. These are important findings considering that approximately 34 percent of U.S. adults have been classified as obese and given the health concerns related to obesity, such as type 2 diabetes (T2DM) and metabolic syndrome.

"We are excited about these promising findings for mangos, which contain many bioactive compounds, including mangiferin, an antioxidant that may contribute to the beneficial effects of mango on blood glucose. In addition, mangos contain fiber, which can help lower glucose absorption into the blood stream," said Edralin Lucas, Ph.D., associate professor of nutritional sciences at Oklahoma State University, College of Human Sciences and lead study author. "Our results indicate that daily consumption of 10 grams of freeze-dried mango, which is equivalent to about one-half of a fresh mango (about 100 grams), may help lower blood sugar in obese individuals."

This pilot study was designed to investigate the effects of mango consumption on anthropometric measurements, biochemical parameters, and body composition in obese adults. Participants completing the 12-week study included 20 adults (11 males and 9 females) ages 20 to 50 years old with a Body Mass Index (BMI) of 30 to 45 kg/m2. The study subjects were asked to maintain their usual diet, exercise habits, and regimen of regularly prescribed medications.

Each day during the study period, participants consumed 10 grams of freeze-dried mango, and dietary intake was monitored via 3-day food records assessed at baseline and after 6- and 12- weeks of mango supplementation. Anthropometric measurements (height, weight, and circumference of waist and hip) were measured at baseline and after 6- and 12- weeks of mango supplementation. Body composition and blood analyses of fasting blood triglyceride, HDL-cholesterol, glucose, hemoglobin A1c, and plasma insulin concentration were evaluated at baseline and at the end of 12 weeks of mango supplementation.

The researchers found that after 12 weeks, participants had reduced blood glucose (-4.41 mg/dL, P<0 .001="" after="" agreement="" although="" and="" animal="" are="" be="" blood="" bmi="" body="" both="" but="" by="" changes="" circumference="" cm="" dl="" effect="" fat="" females.="" females="" findings="" gender="" glucose="" hdl-cholesterol="" higher="" hip="" however="" i="" in="" kg="" lean="" lower="" lowering="" lucas="" m2="" males="" mango="" mass.="" mass="" mg="" no="" not="" observed="" of="" or="" overall="" p="0.062)" percent="" pressure.="" previous="" published="" ratio="" research="" results="" seen="" significant.="" significant="" significantly="" statistically="" study="" sugar="" supplementation="" tended="" the="" there="" these="" this="" to="" triglycerides="" waist="" was="" weight="" were="" which="" with="">British Journal of Nutrition

"We believe this research suggests that mangos may give obese individuals a dietary option in helping them maintain or lower their blood sugar. However, the precise component and mechanism has yet to be found and further clinical trials are necessary, particularly in those that have problems with sugar control, such as diabetics, are necessary," said Lucas.

Results from this present study could have been influenced by a number of factors including the small sample size, lack of a control group, duration of mango supplementation, inaccurate self-reporting of dietary intake and physical activity level by study subjects, or from lack of compliance with daily mango supplementation as part of the study protocol. Additional human studies with larger sample sizes and of longer duration of mango supplementation should be conducted.

A nutrient rich fruit, mangos contain over 20 different vitamins and minerals, supporting optimal function of processes throughout the body. Mangos are an excellent source of the antioxidant vitamins C and A as well as folate. They are also a good source of fiber, copper, and vitamin B6.

Pomegranate stems Alzheimer's

Alzheimer's disease can be slowed and some of its symptoms curbed by a natural compound that is found in pomegranate, according to the findings of a two-year project headed by University of Huddersfield scientist Dr Olumayokun Olajide, who specialises in the anti-inflammatory properties of natural products.

Now, a new phase of research can explore the development of drugs that will stem the development of dementias such as Alzheimer's, which affects some 800,000 people in the UK, with 163,000 new cases a year being diagnosed. Globally, there are at least 44.4 million dementia sufferers, with the numbers expected to soar.

The key breakthrough by Dr Olajide and his co-researchers is to demonstrate that punicalagin, which is a polyphenol – a form of chemical compound – found in pomegranate fruit, can inhibit inflammation in specialised brain cells known as micrologia. This inflammation leads to the destruction of more and more brain cells, making the condition of Alzheimer's sufferers progressively worse.

There is still no cure for the disease, but the punicalagin in pomegranate could prevent it or slow down its development.

Dr Olajide worked with co-researchers – including four PhD students – in the University of Huddersfield's Department of Pharmacy and with scientists at the University of Freiburg in Germany. The team used brain cells isolated from rats in order to test their findings. Now the research is published in the latest edition of the journal Molecular Nutrition & Food Research and Dr Olajide will start to disseminate his findings at academic conferences.

He is still working on the amounts of pomegranate that are required, in order to be effective.
The researchers found that compared to people who never ate fruit, those who ate fruit daily cut their CVD risks by 25-40% (around 15% for IHD, around 25% for ischaemic stroke and 40% for haemorrhagic stroke). There was a dose response relationship between the frequency of fruit consumption and the risk of CVD.
Dr Du said: "Our data clearly shows that eating fresh fruit can reduce the risk of cardiovascular disease, including ischaemic heart disease and stroke (particularly haemorrhagic stroke). And not only that, the more fruit you eat the more your CVD risk goes down. It does suggest that eating more fruit is beneficial compared to less or no fruit."
The researchers also found that people who consumed fruit more often had significantly lower blood pressure (BP). Eating fruit daily was associated with 3.4/4.1 mmHg lower systolic/diastolic BP compared to those who never ate fruit. Dr Du said: "Our data shows that eating fresh fruit was associated with lower baseline BP. We also found that the beneficial effect of fruit on the risk of CVD was independent of its impact on baseline BP."
In a separate analysis, the researchers examined the association of fruit consumption with total mortality and CV mortality in more than 61 000 patients from the China Kadoorie Biobank who had CVD or hypertension at baseline. They found that compared to those who never ate fruit, daily consumers of fruit cut their overall risk of death by 32%. They also reduced their risks of dying from IHD by 27% and from stroke by around 40%.
Professor Zhengming Chen, the principal investigator of the China Kadoorie Biobank, said: "Patients with CVD and hypertension should also be encouraged to consume more fresh fruit. Many western populations have experienced a rapid decrease in CVD mortality during the past several decades, especially stroke mortality since the early 1950s, for reasons that are not yet fully explained. Improved access to fresh fruit may well have contributed importantly to that decline."
The researchers concluded: "Our results show the benefit of eating fruit in the healthy general population and in patients with CVD and hypertension. Fruit consumption is an effective way to cut CVD risk and should not only be regarded as 'might be useful'. Policies are needed to promote the availability, affordability and acceptability of fresh fruit through educational and regulatory measures."

"But we do know that regular intake and regular consumption of pomegranate has a lot of health benefits – including prevention of neuro-inflammation related to dementia," he says, recommending juice products that are 100 per cent pomegranate, meaning that approximately 3.4 per cent will be punicalagin, the compound that slows down the progression of dementia.

Dr Olajide states that most of the anti-oxidant compounds are found in the outer skin of the pomegranate, not in the soft part of the fruit.

The research continues and now Dr Olajide is collaborating with his University of Huddersfield colleague, the organic chemist Dr Karl Hemming. They will attempt to produce compound derivatives of punicalagin that could the basis of new, orally administered drugs that would treat neuro-inflammation.

Dr Olajide has been a Senior Lecturer at the University of Huddersfield for four years. His academic career includes a post as a Humboldt Postdoctoral Research Fellow at the Centre for Drug Research at the University of Munich. His PhD was awarded from the University of Ibadan in his native Nigeria, after an investigation of the anti-inflammatory properties of natural products.

He attributes this area of research to his upbringing. "African mothers normally treat sick children with natural substances such as herbs. My mum certainly used a lot of those substances. And then I went on to study pharmacology!"


Pomegranate-date cocktail a day keeps the doctor away

Glorious, red pomegranates and their Middle Eastern sister, luscious toffee-like dates, are delicious, increasingly trendy, and healthy to boot. As it turns out, when consumed together they are a winning combination in the war against heart disease. Just half a glass of pomegranate juice a day with a handful of dates can do the trick!

A team of researchers at the Technion-Israel Institute of Technology, led by Professor Michael Aviram of the Rappaport Faculty of Medicine and Rambam Medical Center, has discovered that the combination of pomegranate juice and dates along with their pits provide maximum protection against atherosclerosis (plaque buildup or hardening of the arteries), which can cause a heart attack or stroke. The findings were published in the most recent issue (March 26, 2015) of Food & Function, a journal of The Royal Society of Chemistry.

A number of risk factors are involved in the development of atherosclerosis, including cholesterol oxidation, which leads to accumulation of lipids in the arterial wall. Natural antioxidants can slow down the oxidation process in the body, and serve to reduce the risk of heart attack. For the past 25 years, Prof. Aviram and his research team have been working on isolating and researching those antioxidants, in order to keep plaque buildup at bay.
Going into the most recent study, the team was aware of the individual benefits provided by pomegranates and dates. Pomegranate juice, rich in polyphenolic antioxidants (derived from plants), has been shown to most significantly reduce oxidative stress. Dates, which are rich sources of phenolic radical scavenger antioxidants, also inhibit the oxidation of LDL (the so-called "bad cholesterol") and stimulate the removal of cholesterol from lipid-laden arterial cells.

Prof. Aviram had a hunch that since dates and pomegranate juice are composed of different phenolic antioxidants, the combination could thus prove more beneficial than the sum of its parts.

In a trial performed on arterial cells in culture, as well as in atherosclerotic mice, the Technion team found that the triple combination of pomegranate juice, date fruits and date pits did indeed provide maximum protection against the development of atherosclerosis because the combination reduced oxidative stress in the arterial wall by 33% and decreased arterial cholesterol content by 28%.

The researchers conclude that people at high risk for cardiovascular diseases, as well as healthy individuals, could benefit from consuming the combination of half a glass of pomegranate juice (4 ounces), together with 3 dates. Ideally, the pits should be ground up into a paste and eaten as well, but even without the pits, the combination is better than either fruit alone.


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