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17 July 2009

Strawberries: Sweet and Tasty Treat with Anti-Aging Power

Strawberries are one of nature’s healthiest "packages" of power nutrients. There is strong evidence that strawberries are a heart-protective fruit, an anti-cancer fruit, and an anti-inflammatory fruit all rolled into one ripe treat.

Let’s have a look at strawberries health benefits.

1 Powerful Mix of Vitamins, Phytochemicals & Antioxidants

One of the top benefits of strawberries is their antioxidant and phytonutrient content, which give strawberries heart-protecting, anti-inflammatory, and anti-cancer properties. According to a US Department of Agriculture study[1], strawberries rank third when compared to the top fresh fruits and vegetables.

Strawberries are widely known for their potential health benefits due to their high vitamin C, fiber, B-vitamins, potassium, and folic acid contents.

In addition, strawberries are abundant in phytonutrients, including flavonoids, anthocyanidins and ellagic acid, that have been the subject of much investigation by numerous research laboratories.

2 Cancer Prevention

There have been many published reports on the anticancer effects of strawberries. Strawberries are one of the few sources, along with raspberries and grapes, of ellagic acid, a compound which has been shown to prevent carcinogens from turning healthy cells into cancerous ones.

The anticarcinogenic effect of ellagic acid was shown in several types of cancers including skin, esophageal[8], breast, colon, and pancreas[7] cancers.

Besides ellagic acids strawberries contain a multitude of cancer-fighting compounds, including vitamin C, folate, anthocyanins, quercetin and kaempferol. Very few foods or their compounds have been shown to reduce risk of some cancers. However, strawberries have shown promise in both cell culture[5] and epidemiological studies[6].

3 Cardiovascular Disease Protection

New research from Harvard Medical School[9] found that strawberries may offer cardiovascular disease protection. The study found that those who reported eating the most strawberries experienced lower blood levels of C-reactive protein.

C-reactive protein or CRP is a blood biomarker that signals the presence of inflammation in the body. Elevated levels of CRP have been shown in multiple studies to be a potentially good predictor of risk for both heart disease and stroke, as it is generally a signal of atherosclerosis.

4 Anti-clotting Effect

Strawberry consumption may protect against blood clot formation.

An animal study[10] found strawberries had a powerful anti-clotting effect. Strawberry extracts were shown to produce anti-clotting (anti-thrombotic) properties in mice, an effect possibly mediated by inhibiting platelet activity and by producing antioxidant effects.

Prevention of Atherosclerosis

Until this century, it was not known that strawberries contain ellagic acid - a natural organic compound that several studies have shown to have a beneficial health effect.

Researchers found that ellagic acid has anti-inflammatory properties and may play an important role in the prevention of arterial plaques (atherosclerosis)[11].

6 Fountain of Youth: Prevents Neuronal and Behavioral Aging

Strawberries may protect against the decline of the central nervous system in age-related neurodegenerative diseases and to provide benefits to the aging brain[2].

"Research suggests that the polyphenolic compounds found in berry fruits, such as blueberries and strawberries, may exert their beneficial effects either through their ability to lower oxidative stress and inflammation or directly by altering the signaling involved in neuronal communication, calcium buffering ability, neuroprotective stress shock proteins, plasticity, and stress signaling pathways. These interventions, in turn, may exert protection against age-related deficits in cognitive and motor function."[3]

Recently researchers at the USDA Human Nutrition Research Center on Aging at Tufts University, showed that strawberry extract slowed the age-related decline in cognitive function[4].

Now researchers are looking at the effects of strawberry supplementation in three areas: behavioral aging, repair and regeneration of nerve cells in aging, and resistance to oxidative stress in aging.

7Sweet and Delicious, But Low in Sugar and Calories

Strawberries have a low Glycemic Index of 40. It is that rare case when sweet and tasty treat is waist-friendly and good for your health.

8 Help to Lower Cholesterol Levels

Researchers at the University of Toronto found that antioxidants in strawberries help lower "bad" cholesterol[13]. The study showed that the antioxidant power in strawberries can improve and maintain the effectiveness of cholesterol-lowering diets.

The researchers also found that people who consumed strawberries had reduced oxidative damage to LDL cholesterol. LDL cholesterol is even more damaging when it becomes oxidized.

9 Reduce Risk of Rheumatoid Arthritis

One of the benefits of strawberries may be protection against rheumatoid arthritis.

Strawberries contain a lot of vitamin C. In fact, about eight medium berries provide 160 percent of the recommended daily allowance (RDA) of vitamin C.

A large population based study[14] of more than 20,000 people found that consumption of foods high in vitamin C seem to protect against inflammatory polyarthritis, a form of rheumatoid arthritis involving two or more joints.

Participants who consumed the lowest amounts of vitamin C were three times more likely to develop the arthritic condition than those who consumed the highest amounts of vitamin C.

10 Prevent Ultraviolet Skin Damage

Ellagic acid, an antioxidant found in raspberries, strawberries, cranberries and pomegranates, may help prevent wrinkles and repair skin damage caused by the sun.

Researchers from Hallym University in South Korea applied ellagic acid to human skin cells in the lab and to the skin of hairless mice that had been exposed to strong, ultraviolet rays. In the human cells, ellagic acid reduced the destruction of collagen and inflammatory response, both major causes of wrinkles. Researchers had a similar result in 4-week-old mice, which are often used in dermatology studies because their skin is similar to that of humans.

11 Prevent Ulcers (Helicobacter pylori infection)

Berry extracts help kill the bacteria that cause most ulcers and improve the efficacy of prescription ulcer therapy, according to a report from Creighton University in Omaha, NE. The Nebraska researchers[15] demonstrated that berry extracts not only inhibit the growth of H. pylori, but also render it more susceptible to clarithromycin, one of the antibiotics used to eradicate the bacteria.

12 Enhance Vision (Macular Degeneration)

According to a study in the Archives of Ophthalmology, eating three or more servings of fruit per day may lower a person’s risk of age-related macular degeneration by 36 percent[16].

It is not known exactly how fruit helps to protect against age-related macular degeneration. It is thought that the antioxidants in fruit may help protect macular cells in the retina by neutralising free radicals. However, because the antioxidant vitamins and carotenes did not contribute to the prevention in age-related macular degeneration, it is possible that other molecules in fruit may be playing a role.

16 July 2009

Oily fish may reduce dementia risk: Transcontinental study

Increased intake of fish may reduce the risk of dementia by about 20 per cent, according to a new study spanning three continents.

Data from 14,960 people in seven countries indicated that the more fish consumed, the more beneficial the effects, researchers report in the American Journal of Clinical Nutrition.

“We showed for the first time that a statistically significant trend toward a lower prevalence of dementia among those with higher dietary fish intake in large population-based samples of older people living in 5 countries in Latin America, China, and India,” wrote the researchers led by Emiliano Albanese from King’s College London.

“Our results extend findings on the associations of fish and meat consumption with dementia risk to populations in low- and middle-income countries and are consistent with mechanistic data on the neuroprotective actions of omega-3 long-chain polyunsaturated fatty acids commonly found in fish,” they added.

Two earlier studies published in April 2007 in the American Journal of Clinical Nutrition reported that regular consumption of omega-3-rich food could prevent age-related cognitive decline.

The studies, from the Dutch National Institute for Public Health and the Environment, and the University of North Carolina, stated that only a limited number of studies have looked at the decline in cognitive function that precedes these diseases.

The majority of science for the health benefits of fish and omega-3 consumption has focused on cardiovascular health, but the science for cognitive benefits is growing and almost as compelling as the heart health data.

Transcontinental support

Albanese and his co-workers examined the links between dementia and fish and meat intake in low- and middle-income countries, including China, India, Cuba, the Dominican Republic, Venezuela, Mexico, and Peru.

“To our knowledge, this is the largest population-based study on this topic to date from either developing or developed country samples,” they said.

Almost 15,000 people aged 65 or over were surveyed. After adjusting for various confounders and pooling the data from all the sites, the researchers report that they observed a dose-dependent inverse association between dementia and fish consumption.

On the other hand, meat consumption was found to increase dementia risk.

“More substantive evidence will come from the incidence phase of our project, in which we will be able to compare the incidence of dementia according to dietary exposure at baseline, and from randomized controlled trials of the effectiveness of n-3 long-chain polyunsaturated fatty acids supplementation for the prevention of cognitive decline,” said the researchers.

Barefoot Running May Be Better For You

A small but growing body of research suggests that barefoot is the way to run. As a result, many runners have been shucking off their shoes in favor of naked feet or minimalist footwear.

Strong evidence shows that thickly cushioned running shoes have done nothing to prevent injury in the 30-odd years since Nike founder Bill Bowerman invented them. Some smaller, earlier studies suggest that running in shoes may increase the risk of ankle sprains, plantar fasciitis and other injuries. Injuries plague 20 to 80 percent of regular runners every year.

Going shoeless allows your foot to flex and absorb shock. With thick heels, people lengthen their strides, landing heel-first and letting the shoe absorb the impact of each footfall. You can’t do that barefoot, so your body naturally falls into a shorter stride, landing first on the outside middle or ball of your foot. As you advance your foot rolls inward; the arch flattens and helps absorb the impact; it then springs back up as you lift your foot and push off the ground.

Vegetable Amino Acid Lowers Blood Pressure

WEDNESDAY, July 8 (HealthDay News) -- Researchers say they have discovered that one of the most common amino acids in vegetable protein seems to lower blood pressure.

Analysis of data from an international diet study shows that a 4.72 percent higher intake of glutamic acid as a portion of total dietary protein correlates with a 1.5- to 3-point reduction in average systolic blood pressure (the higher of the two blood pressure readings, when the heart beats) and a 1- to 1.6-point lower diastolic pressure (the lower reading, when the heart rests between beats). The report appears online July 6 in advance of publication in an upcoming print issue of the journal Circulation.

The point difference might not sound like much, but high blood pressure is a leading risk factor for heart disease, stroke and other cardiovascular problems, and a reduction on that scale could cut stroke death rates by 6 percent and coronary heart disease deaths by 4 percent, said study author Dr. Jeremiah Stamler, professor emeritus of preventive medicine at the Feinberg School of Medicine at Northwestern University in Chicago.

However, the worry is that people could take the finding as a reason to pop glutamic acid pills rather than making vegetables a larger part of their diet, Stamler said.

"We make a clear statement that there are no data on supplements of glutamic acid to tell us anything one way or another about their value," Stamler said.

Protein, animal and vegetable, consists of chains of amino acids. Glutamic acid is the most common of those amino acids, accounting for 23 percent of vegetable protein and 18 percent of meat protein.

The relationship between higher glutamic acid intake and lower blood pressure seen in the study of 4,680 people in China, Japan, the United States and the United Kingdom was not unexpected, said Ian J. Brown, a research associate in epidemiology and public health at Imperial College London, and a member of the research team.

"It is compatible with earlier findings that a diet high in vegetable proteins, those found in beans, whole grains, rice, soy products and bread, is associated with lower blood pressure," Brown said.

"The fact that the most important amino acid in vegetable protein is related to blood pressure supports the inference that a diet high in vegetable protein and low in animal protein has favorable effects on blood pressure," Stamler added.

Similar but lesser effects on lowering blood pressure have been found for other amino acids more common in vegetable protein, such as proline, phenylalanine and serine, Brown said.

"The solution to improving blood pressure is not based around a single nutrient," he said. "We are looking at a whole series of dietary elements that act together. Combined, they have a large effect."

But diet is not the only factor to be considered in attacking high blood pressure, Stamler said.

"We must also consider obesity, high salt intake, high alcohol intake and high potassium intake, among other risk factors," he said.

Still, the study provides evidence why the Dietary Approaches to Stop Hypertension (DASH) diet, developed by the U.S. National Institutes of Health, reduces blood pressure, Stamler said. The DASH diet is rich in fruits, vegetables, whole grains, lean poultry, nuts and beans.

"It's just as mothers and grandmothers have been saying for years," Brown said. "Eat your vegetables, avoid fatty foods, avoid excess alcohol."

15 July 2009

Magnetic brain stimulation improves skill learning

The use of magnetic pulses to stimulate the dorsal premotor cortex (PMd) region of the brain results in an improved ability to learn a skilled motor task. Researchers writing in the open access journal BMC Neuroscience show that skilled movements can be stored as memories in the PMd and that magnetic stimulation of this area can facilitate this learning process.

Lara Boyd and Meghan Linsdell, from the University of British Columbia, studied the effect of transcranial magnetic stimulation of the PMd on the ability of 30 volunteers to track a target on a computer screen using a joystick. During the task, the target would move randomly, then enter a programmed pattern and finally return to moving randomly. The participants were not aware of the repeated section, believing that movements were random throughout.

The volunteers received four days of training, during which they were either given excitatory stimulation, inhibitory stimulation or sham stimulation immediately before practicing the motor task. The volunteers were not aware which group they were in. On the fifth day, they were tested to see how well they had learned the task. By comparing the improvements between the random and repeated sections of the task, the researchers were able to separate the general improvement due to practice from the learned motor memory of the repeated section.

Those participants who had received the excitatory stimulation were significantly better than the other groups at tracking the target during the repeated section of the test. They showed no significant difference in improvement during the random sections. The researchers conclude, "Our data support the hypothesis that the PMd is important for continuous motor learning, specifically via off-line consolidation of learned motor behaviors".

2 dietary oils, 2 sets of benefits for older women with diabetes

COLUMBUS, Ohio – A study comparing how two common dietary oil supplements affect body composition suggests that both oils, by themselves, can lower body fat in obese postmenopausal women with Type 2 diabetes.

The two oils compared were safflower oil, a common cooking oil, and conjugated linoleic acid (CLA), a compound naturally found in some meat and dairy products that has been associated with weight loss in previous studies. Both are composed primarily of polyunsaturated fatty acids, which are considered "good fats" that, when consumed in proper quantities, are associated with a variety of health benefits.

In the study, 16 weeks of supplementation with safflower oil reduced fat in the trunk area, lowered blood sugar and increased muscle tissue in the women participants.

Conjugated linoleic acid supplementation for the same length of time, on the other hand, reduced total body fat and lowered the women's body mass index (BMI), a common health measure of weight relative to height.

All of the women in the study took one oil for 16 weeks, followed by the other oil for an equal amount of time. The participants were instructed not to change their diets or exercise patterns over the course of the study so the research would measure the effects of only the supplementation.

"Making this subtle change in the intake of high-quality dietary fats in an effort to alter body composition is both achievable and affordable to postmenopausal women in the United States who are managing the difficult combination of obesity and diabetes," said Martha Belury, professor of human nutrition at Ohio State University and senior author of the study.

Among the most surprising findings: that in 16 weeks, these women could lose between about two pounds and four pounds of trunk fat simply by taking safflower oil supplements.

"I never would have imagined such a finding. This study is the first to show that such a modest amount of a linoleic acid-rich oil may have a profound effect on body composition in women," Belury said. The dose of either oil taken each day was approximately 1 2/3 teaspoons.

Postmenopausal women tend to lose muscle at the same time that body fat accumulates toward their middle, so this research shows how dietary oils can complement lifestyle and medication in helping older diabetic women manage their health, she said.

The research appears online and is scheduled for later print publication in the American Journal of Clinical Nutrition.

Thirty-five women participated in the study. All were considered obese based on their BMI measures of 30 or higher, were postmenopausal but younger than age 70, and had Type 2 diabetes but did not need to take insulin to treat the disease. Many did take other medications, such as those used to manage blood sugar levels, cholesterol or blood pressure.

The women were randomized into two groups to determine which supplement they took first. Each initial 16-week supplementation was followed by a four-week washout period to remove the first supplement from their systems before the next 16-week supplementation period began. The supplements were contained in eight pills; the women took two pills four times per day, at meals and bedtime.

"The power of the crossover is that it tells you the different effects of the dietary oils in the same woman," Belury said.

The daily supplementation contained 6.4 grams of each oil's active fatty acid: linoleic acid in safflower oil and, in CLA, specific fatty acid isomers – compounds that share the same chemical formula but differ in chemical structure.

The researchers used dual-energy X-ray absorptiometry, commonly known as DXA and usually used to measure bone density, to determine the women's baseline and follow-up lean mass and fat throughout their bodies and specifically in their trunk region.

Researchers asked the participants to keep diet and activity records for three consecutive days at four points over the course of the study to account for the potential for calorie intake or exercise to affect the results, Belury said. Physical activity remained unchanged throughout the study, and no significant differences were seen between the two groups' reported calorie intake.

The study showed that CLA supplementation significantly decreased body mass index and total body fat over both diet periods, typically showing effects in the last half of each 16-week period. The BMI levels of the women taking CLA dropped on average by about half a point, and their total body fat decreased by an average of 3.2 percent, reducing the weight of the fat tissue by an average of between 2.3 pounds and 3.5 pounds.

Safflower oil supplementation showed no effect on total body fat readings, but reduced the weight of trunk fat tissue by between 2.6 pounds and 4.2 pounds, or an average of 6.3 percent. It also increased lean tissue, or muscle, by between an average of about 1.4 pounds and 3 pounds.

Safflower oil also lowered fasting blood sugar levels by between 11 and 19 points on average. Blood sugar is considered normal if it falls below 110 milligrams per deciliter; the women's average blood sugar levels ranged from 129 to 148 after 16 weeks of safflower oil supplementation.

"Lowering fasting glucose is important for these women. The overall effect in just 16 weeks wasn't bringing them back to normal, but safflower oil still improved it significantly," Belury said.

The dietary oils did not have significant effects on other health measurements, such as waist circumference, waist-to-hip ratio and skinfold thickness measures of body fat, Belury noted.

The CLA also did not appear to affect the variety of hormones involved in fat burning. However, safflower oil increased a hormone called adiponectin. Increasing this hormone may have instilled an improved ability to burn dietary fats, said Belury, who hopes to investigate this mechanism in a follow-up study.

Belury said that other work she is conducting in animals suggests that at least in the case of CLA, the fatty acid appears to allow the body to burn calories in a heat-producing way. Questions remain about the long-term safety of any kind of supplementation that lowers body fat, because some research has suggested that the fat that leaves fat tissue ends up in the liver or muscles – a condition that could lead to insulin resistance and diabetes if that fat can't be used.

Neither CLA nor the linoleic acid in safflower oil is naturally produced in the human body, so both must be obtained from food or dietary supplements. Linoleic acid is an omega-6 fatty acid that is important in growth and maintenance of tissues and lipid metabolism. The American Heart Association recently issued recommendations suggesting that omega-6 fatty acids are among the polyunsaturated fats that should be consumed for heart health.

CLA is found naturally in trace amounts primarily in beef, lamb and milk, but obtaining levels comparable to those used in Belury's study likely requires concentrated doses similar to those found in dietary supplements.

"Essentially what we're trying to understand with nutrition is how dietary approaches can complement Westernized medicine," Belury said. "In an ideal world, we'd love it if women like those in our study could use diet, activity and other aspects of a healthy lifestyle to manage their health. But most will probably be on oral medications for the rest of their lives for managing their diabetes and metabolism, which is fine as long as the medications work. We think there's a chance that nutrition can complement medication and help drugs work even better."

Chlorine in Your Baby Carrots

The small cocktail or “baby” carrots you buy are made using the larger crooked or deformed carrots which are put through a machine which cuts and shapes them into cocktail carrots. You might have known that already. But what you might not know is that once the carrots are cut and shaped into cocktail carrots, they are dipped in a solution of water and chlorine in order to preserve them.

When a baby carrot turns white (“white blushing”), this causes the bags of carrots to be pulled from the shelf and thrown away. To prevent this consumer waste, the carrots are dipped in chlorine to prevent the white blushing from happening.

Chlorine is a very well-known carcinogen. Organic growers instead use a citrus based, nontoxic solution called Citrox.

What's in that bottle? Congress says water unclear

WASHINGTON (Reuters) - Bottled water makers make millions off people who believe their products are purer than tap water, but consumers do not realize that they are less regulated than plain old tap water, according to a U.S. Congressional report released on Wednesday.

The report from the General Accountability Office also found that the U.S. Food and Drug Administration has little power to regulate the safety of bottled water, and even states with the power to regulate it concentrate more on tap water.

The report was just one piece of ammunition unleashed at the bottled water industry at a hearing of the House of Representatives Energy and Commerce Subcommittee on Oversight and Investigations.

"Of particular note, FDA does not have the specific statutory authority to require bottlers to use certified laboratories for water quality tests or to report test results, even if violations of the standards are found," the GAO report reads.

Jane Houlihan of the Environmental Working Group, an advocacy organization that submitted a second report to the committee, said in a statement: "Many people assume bottled water is healthier and safer to drink than ordinary tap water.

"But some companies have lured consumers away from the tap with claims of health and purity that aren't backed by public data."

Sponsors of the hearing agreed.

"Americans are willing to pay top dollar for bottled water, which costs up to 1,900 times more than tap water and uses up to 2,000 times more energy to produce and deliver," Michigan Representative Bart Stupak told the hearing.


"Over the past several years, however, bottled water has been recalled due to contamination by arsenic, bromate, cleaning compounds, mold, and bacteria. In April, a dozen students at a California junior high school reportedly were sickened after drinking bottled water from a vending machine."

Joseph Doss, president and chief executive officer of the International Bottled Water Association, told the hearing that Americans drank 8.7 billion gallons (33 billion liters) of water in 2008, or 28.5 gallons (108 liters) per person.

"Sales revenues for the United States bottled water market in 2008 were approximately $11.2 billion," Doss said. "Bottled water consumption is about half that of carbonated soft drinks and only slightly ahead of milk and beer.

The GAO found that the FDA does not regulate a compound called DEHP in bottled water. The Environmental Protection Agency regulated levels of DEHP, a so-called phthalate linked to some health risks, in tap water.

"Specifically, FDA deferred action on DEHP in a final rule published in 1996 and has yet to either adopt a standard or publish a reason for not doing so on the safety of bottled water," the GAO said.

Doss said DEHP was unlikely to be in bottled water, which he said was governed by several layers of regulation.

Obesity health risk cause 'found'

Scientists believe they may have uncovered a key reason why obese people have a raised risk of health complications such as type 2 diabetes.

They blame a specific protein - pigment epithelium-derived factor (PEDF) - which is secreted by fat cells.

The Australian and US research on mice suggests blocking some of PEDF's action may reverse some complications - raising hopes of new drug treatments.

The study appears in the journal Cell Metabolism.

In light of our findings, we believe that blocking PEDF will ameliorate several obesity-related complications

Dr Matthew Watt
Monash University
Because PEDF is produced by fat cells people who are overweight have higher levels of the protein in the bloodstream.

The latest research shows that the protein sends a signal to other tissues in the body, triggering development of insulin resistance - a condition that often leads to type 2 diabetes - in the muscle and liver.

Raised PEDF levels were also linked to a release of fats into the bloodstream, raising the risk of complications such as heart disease.


In tests on obese mice, the researchers found that treatments designed to block the action of PEDF lowered the animals' blood fat level and reversed some of their insulin resistance.

Fat cells are known to play an important role in regulating the body's metabolism by releasing hormones and other chemicals.

This pattern of secretion is also known to change with the size of the fat cells.

The latest study set out to identify which of these secretions had a profound general impact on metabolism.

Tackling insulin resistance directly, even in the absence of weight loss, could potentially strengthen our ability to help obese patients reduce their risk of life-shortening disease

Dr Ian Campbell, medical director of the charity Weight Concern
The researchers took particular interest in PEDF because it was already known that levels of the protein were raised in people with type 2 diabetes, and metabolic syndrome - a collection of risk factors including too much belly fat, high cholesterol and high blood pressure.

They found that of all the molecules secreted by fat cells PEDF was among the most abundant.

They also showed that PEDF levels fell in obese mice when they lost weight, either by using diet or drugs.

When lean mice were injected with PEDF they showed signs of developing insulin resistance and inflammation in both muscle and liver.

And in the long term, PEDF raised fat levels in the animals' blood.

These fats were transported into the muscle and liver, where they accumulated, raising the risk of insulin resistance still further.


But when obese mice were given treatment to neutralise PEDF their sensitivity to insulin improved, reducing their risk of diabetes, and the level of fats in their blood fell.

Researcher Dr Matthew Watt, from Monash University in Australia, said: "In light of our findings, we believe that blocking PEDF will ameliorate several obesity-related complications."

He said previous research had suggested that PEDF also protects against furring of the arteries and excessive blood vessel growth and helps keep the nervous system healthy.

But he said new drugs could be at least five years away.

Dr Victoria King, of Diabetes UK, said: "While this study has been carried out in mice, there has been some indication from other studies that higher levels of this protein found in overweight people with type 2 diabetes could indicate that a similar process is occurring in humans.

"But this would need to be studied further and verified."

Dr Ian Campbell, medical director of the charity Weight Concern, said: "If we were able to somehow switch off or limit the activities of this, or related compounds it could open up new possibilities for drug treatments, not for obesity, but for the secondary effects.

"To date weight loss drugs though effective are often not effective enough.

"Tackling insulin resistance directly, even in the absence of weight loss, could potentially strengthen our ability to help obese patients reduce their risk of life-shortening disease."

Professor Ian MacDonald, an expert in the chemistry of nutrition at the University of Nottingham, said PEDF was one of many chemicals produced by fat cells and it was unclear how they all interacted with each other.