All Posts tagged scientists

Tomatoes Fight Cholesterol

If you want to wage battle against cholesterol and other lipids (fat) that can contribute to vascular disease, then make tomatoes a big part of your diet. Scientists say this popular fruit contains a nutrient that can fight vascular disease such as stroke and arteriosclerosis.

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Tomatoes fight more than cholesterol and fat

Excessive levels of lipids, such as cholesterol and triglycerides in the bloodstream, a condition known as dyslipidemia, can lead to potentially deadly diseases such as arteriosclerosis, cirrhosis, and stroke. Scientists from Kyoto University and New Bio-industry Initiatives, Japan, report that a compound called 9-oxo-octadecadienoic extracted from tomatoes can boost oxidation of fatty acids and contribute to the regulation of lipid metabolism by the liver. These qualities indicate that 9-oxo-octadecadienoic acid can fight cholesterol and other lipids and therefore help prevent vascular diseases.

Vascular disease is a general term used to describe diseases that affect the blood vessels. The Vascular Disease Foundation offers information on nearly two dozen different conditions that fit this category, including abdominal aortic aneurysm, carotid artery disease, deep vein thrombosis, lymphedema, peripheral artery disease, and stroke.

Tomatoes are also valued for other health benefits. Much research has been dedicated to a potent antioxidant in tomatoes, lycopene, and its potential in the fight against various types of cancer, and especially prostate cancer. Tomatoes also contain excellent levels of other nutrients, including niacin, which helps lower cholesterol; and potassium, which reduces blood pressure and the risk of heart disease.

Dr. Teruo Kawada, who is from Kyoto University and who led the study, noted that “Finding a compound which helps the prevention of obesity-related chronic diseases in foodstuffs is a great advantage to tackling these diseases. It means that the tomato allows people to easily manage the onset of dyslipidemia through their daily diet.” To help the fight against cholesterol and other fats that contribute to vascular disease, enjoy more tomatoes.

SOURCES:
Kim YI et al. Molecular Nutrition & Food Research doi:10.1002/mnfr.201000264

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Genetic damage minutes after smoking

In research described as “a stark warning” to those tempted to start smoking, scientists are reporting that cigarette smoke begins to cause genetic damage within minutes — not years — after inhalation into the lungs. Their report, the first human study to detail the way certain substances in tobacco cause DNA damage linked to cancer, appears in Chemical Research in Toxicology, one of 38 peer-reviewed scientific journals published by the American Chemical Society.

Stephen S. Hecht, Ph.D., and colleagues point out in the report that lung cancer claims a global toll of 3,000 lives each day, largely as a result of cigarette smoking. Smoking also is linked to at least 18 other types of cancer. Evidence indicates that harmful substances in tobacco smoke termed polycyclic aromatic hydrocarbons, or PAHs, are one of the culprits in causing lung cancer. Until now, however, scientists had not detailed the specific way in which the PAHs in cigarette smoke cause DNA damage in humans.

The scientists added a labeled PAH, phenanthrene, to cigarettes and tracked its fate in 12 volunteers who smoked the cigarettes. They found that phenanthrene quickly forms a toxic substance in the blood known to trash DNA, causing mutations that can cause cancer. The smokers developed maximum levels of the substance in a time frame that surprised even the researchers: Just 15-30 minutes after the volunteers finished smoking. Researchers said the effect is so fast that it’s equivalent to injecting the substance directly into the bloodstream.

“This study is unique,” writes Hecht, an internationally recognized expert on cancer-causing substances found in cigarette smoke and smokeless tobacco. “It is the first to investigate human metabolism of a PAH specifically delivered by inhalation in cigarette smoke, without interference by other sources of exposure such as air pollution or the diet. The results reported here should serve as a stark warning to those who are considering starting to smoke cigarettes,” the article notes. The authors acknowledged funding from the National Cancer Institute.

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Neanderthals may have feasted on meat and two veg diet

Scientists have upgraded their opinion of Neanderthal cuisine after spotting traces of cooked food on the fossilised teeth of our long-extinct cousins. The researchers found remnants of date palms, seeds and legumes – which include peas and beans – on the teeth of three Neanderthals uncovered in caves in Iraq and Belgium. Among the scraps of food embedded in the plaque on the Neanderthals' teeth were particles of starch from barley and water lilies that showed tell-tale signs of having been cooked. The Ice Age leftovers are believed to be the first direct evidence that the Neanderthal diet included cooked plants as well as meat obtained by hunting wild animals.

Dolores Piperno, who led the study at the archaeobiology laboratory at the Smithsonian National Museum of Natural History in Washington, said the work showed Neanderthals were more sophisticated diners than many academics gave them credit for. Piperno said the discoveries even raised the possibility that male and female Neanderthals had different roles in acquiring and preparing food. “The plants we found are all foods associated with early modern human diets, but we now know Neanderthals were exploiting those plants and cooking them, too. When you cook grains it increases their digestibility and nutritional value,” she added.

The findings bring fresh evidence to the long debate over why Neanderthals and not our direct ancestors, the early modern humans, went extinct. The last of the Neanderthals are thought to have died out around 28,000 years ago, but it is unclear what role – if any – modern humans played in their demise. “The whole question of why Neanderthals went extinct has been controversial for a long time and dietary issues play a significant part in that,” Piperno said. “Some scholars claim the Neanderthals were specialised carnivores hunting large game and weren't able to exploit a diversity of plant foods. “As far as we know, there has been until now no direct evidence that Neanderthals cooked their foods and very little evidence they were consuming plants routinely.”

Piperno's team was given permission to study the remains of three Neanderthal skeletons. One was unearthed at the Shanidar cave in Iraq and lived 46,000 years ago. The other two were recovered from the Cave of Spy in Belgium, and date to around 36,000 years ago. The scientists examined three teeth from the Iraqi Neanderthal and two from each of the Belgium specimens. To look for traces of food on them, they scraped fossilised plaque from each tooth and looked at it under a microscope. Grains from plants are tiny, but have distinct shapes that the scientists identified by comparing them with a collection at the Smithsonian's herbarium. The researchers also cooked a range of plants to see how their appearance changed.

They collected 73 starch grains from the Iraqi Neanderthal's teeth. Some of these belonged to barley or a close relative, and appeared to have been boiled in water. “The evidence for cooking is strong. The starch grains are gelatinised, and that can only come from heat associated with cooking,” Piperno said. Similar tests on the Belgian Neanderthals' teeth revealed traces of cooked starch that probably came from parts of water lilies that store carbohydrates. Other cooked starch grains were traced back to sorghum, a kind of grass.

The study is published in the Proceedings of the National Academy of Sciences journal.

In Piperno's opinion, the research undermines one theory that suggests early modern humans drove the Neanderthals to extinction by having a more sophisticated and robust diet. The work also raises questions about whether Neanderthals organised themselves in a similar way to early hunter-gatherer groups, she said. “When you start routinely to exploit plants in your diet, you can arrange your settlements according to the season. In two months' time you want to be where the cereals are maturing, and later where the date palms are ready to pick. It sounds simplistic, but this is important in terms of your overall cognitive abilities. “In early human groups, women typically collected plants and turned them into food while men hunted. To us, and it is just a suggestion, this brings up the possibility that there was some sexual division of labour in the Neanderthals and that is something most people did not think existed.”

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Study Supports Gluten-Free Diet in Potential Celiac Disease Patients

Findings from a new study of 141 adults add to an ongoing medical debate over which patients with symptoms of celiac disease should go on a gluten-free diet. Published in ACS' Journal of Proteome Research, the study concludes that people currently diagnosed as “potential” celiac disease patients and not advised to follow a gluten-free diet may not be “potential” patients at all. Rather, the scientists found that these patients have the same distinctive metabolic fingerprint as patients with full-blown disease who do benefit from gluten-free diets.

In the study, Ivano Bertini and colleagues explain that celiac disease is an autoimmune digestive disorder characterized by the inability to digest a protein called gliadin, a component of gluten, which is found in wheat, rye, and barley. The condition causes diarrhea, bloating, and other symptoms in over 3 million people in the United States alone. Treatment is avoidance of foods containing gluten. But the disease is often undiagnosed or misdiagnosed. Definitive diagnosis involves biopsy of the small intestine, showing tissue damage. People with a positive blood test for the condition but no positive biopsy usually are diagnosed as “potential” celiac patients and may or may not be advised to follow a gluten-free diet.

The scientists used magnetic resonance metabolic profiling to analyze the biochemical markers in the blood and urine of 61 patients with celiac disease, 29 with potential celiac disease, and 51 healthy people. They found that those with potential disease largely shared the same profile as those with the confirmed disease and that the biochemical markers in both groups differed significantly from those of the healthy individuals. “Our results demonstrate that metabolic alterations may precede the development of small intestinal villous atrophy and provide a further rationale for early institution of gluten-free diet in patients with potential celiac disease, as recently suggested by prospective clinical studies,” the scientists conclude.

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Wholegrains help lower blood pressure

Starting the morning with a bowl of porridge and eating a whole-grain sandwich at lunchtime can help cut the risk of high blood pressure, according to new research. A study carried out by scientists from Aberdeen University which involved more than 200 volunteers revealed that eating three portions of whole-grain foods every day lowers the risk of high blood pressure, a major risk factor for heart disease and stroke. A good deal of research has suggested that a whole-grain diet is good for your health, but this study is one of the first to test the theory in a well-designed clinical trial.

Volunteers in the study ate three servings a day of whole-grain foods, which were either wheat, or a mixture of both wheat and oats. The whole-grain diets were compared with one that contained the same amounts of refined cereals and white bread. The study used foods widely available in supermarkets to make the diet easy to follow, without having to make any changes to their usual lifestyle. Apart from the whole-grain and the equivalent refined cereal foods, the volunteers were encouraged to continue with their normal food choices.

Dr Frank Thies, senior lecturer at The Rowett Institute of Nutrition and Health, who led the study, said: “We observed a decrease in systolic blood pressure of 5-6 mm Hg in the volunteers who ate the whole-grain foods, and this effect is similar to that you might expect to get from using blood pressure-lowering drugs. “This drop in systolic blood pressure could potentially decrease the incidence of heart attack and stroke disease by at least 15 and 25 per cent respectively. The scientists also added that wholegrain wheat and oat-based recipes should be on everyone's festive menu this Christmas.

The findings are published in the American Journal of Clinical Nutrition.

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Watercress may help fight cancer

The pilot study used four women, all of whom were breast cancer survivors, and monitored changes in their blood of key molecules involved in the growth of cancer cells. The participants were asked to fast on the day of the tests and had blood samples taken before and after eating a portion of watercress. The scientists found that six hours after they had eaten the leaves, the women experienced a drop in the activity of a molecule called 4E binding protein, which is thought to be involved in helping cancer cells survive.

Laboratory studies also showed that extracts taken from watercress leaves inhibited the growth of breast cancer cells. The findings build on epidemiological studies that have shown people who eat watercress and other vegetables rich in isothiocyanates, such as broccoli and cabbage, are at lower risk of developing cancer.

Hazel Nunn, Cancer Research UK's health information manager, said the current study was too small to draw any firm conclusions.

She added: “Watercress may well have benefits but there's no reason to believe that it should be superior to a generally healthy, balanced diet that is high in fibre, vegetables and fruit and low in red and processed meat, salt, saturated fat and alcohol.”

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Why a Restricted DIet Leads to Longer Lifespan

The research is being presented at the conference of the British Society for Research on Ageing (BSRA) in Newcastle. It was conducted by scientists at the BBSRC Centre for Integrated Systems Biology of Ageing and Nutrition (CISBAN) at Newcastle University.

Working with the theory that cell senescence – the point at which a cell can no longer replicate – is a major cause of ageing the researchers set out to investigate what effect a restricted diet had on this process. By looking at mice fed a restricted diet the team found that they had a reduced accumulation of senescent cells in their livers and intestines. Both organs are known to accumulate large numbers of these cells as animals age.

Alongside this the CISBAN scientists also found that the telomeres of the chromosomes of the mice on restricted diets were better maintained despite their ageing. Telomeres are the protective 'ends' of chromosomes that prevent errors, and therefore diseases, occurring as DNA replicates throughout an organisms lifetime but they are known to become 'eroded' over time.

The adult mice were fed a restricted diet for a short period of time demonstrating that it may not be necessary to follow a very low calorie diet for a lifetime to gain the benefits the scientists found.

Chunfang Wang, the lead researcher on this project at CISBAN, said: “Many people will have heard of the theory that eating a very low calorie diet can help to extend lifespan and there is a lot of evidence that this is true. However, we need a better understanding of what is actually happening in an organism on a restricted diet. Our research, which looked at parts of the body that easily show biological signs of ageing, suggests that a restricted diet can help to reduce the amount of cell senescence occurring and can reduce damage to protective telomeres. In turn this prevents the accumulation of damaging tissue oxidation which would normally lead to age-related disease.”

Professor Thomas von Zglinicki, who oversaw the research, said: “It's particularly exciting that our experiments found this effect on age-related senescent cells and loss of telomeres, even when food restriction was applied to animals in later life. We don't yet know if food restriction delays ageing in humans, and maybe we wouldn't want it. But at least we now know that interventions can work if started later. This proof of principle encourages us at CISBAN in our search for interventions that might in the foreseeable future be used to combat frailty in old patients.”

CISBAN is one of the six BBSRC Centres for Integrative Systems Biology. The centres represent a more than £40M investment by the Biotechnology and Biological Sciences Research Council (BBSRC) to support the development of systems biology in the UK. The centres are also supported by the Engineering and Physical Sciences Research Council.

Systems biology uses the study of a whole, interconnected system – a cell, an organism or even an ecosystem – with computer modelling to better make the outputs of biology more useful to scientists, policymakers and industry.

Prof Douglas Kell, BBSRC Chief Executive and keynote speaker at the BSRA Conference, said: “As lifespan continues to extend in the developed world we face the challenge of increasing our 'healthspan', that is the years of our lives when we can expect to be healthy and free from serious or chronic illness. By using a systems biology approach to investigate the fundamental mechanisms that underpin the ageing process the CISBAN scientists are helping to find ways to keep more people living healthy, independent lives for longer.”

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Quest for modern Methuselah

The new data was used to create the International Database on Longevity (IDL), http://www.supercentenarians.org/. “The IDL is the first reliable record of scientifically verified data about supercentenarians on an international scope”, says Heiner Maier from the MPIDR. “It is the best existing account of mortality beyond the age of 110.”

Finding the supercentenarians was an unusual task for the demographers, as they could not rely on standard statistical methods. In each country the scientists designed their own strategy of how to identify probable candidates of the super old, and then prove their age by locating official documents that confirmed their date of birth and date of death (or current age if still living).

But there were challenges. In the late 19th century, when the supercentenarians were born, many countries didn't have a central birth register, and often original documents were lost, misplaced or forgotten. So the scientists needed to search through a massive amount of certificates, census lists, death registers and the paper files of universities and health and security administrations to identify supercentenarians.

The findings varied between countries. In the United States 341 supercententarians were eventually found (309 women and 32 men), whereas in the much smaller country of Denmark only two women were verified as being over 110. In some cases going through all of the records would have been logistically impossible. In Germany, for instance, the researchers would have had to sort through records of roughly 8000 Residence Registry Offices. Luckily, however, researchers found a much faster method – they asked the Office of the German President for help. The President keeps a directory of residents older than 100 in order to send birthday congratulations. With the list in hand the researchers easily tracked down 17 supercentenarians.

The record holder in longevity is still the French woman Jeanne Calment, who died in 1997 at the age of 122. The book “Supercentenarians” celebrates her life – how she met the painter Vincent van Gogh when she was 13, how she later allowed herself one glass of port and one cigarette a day, and how she liked good food and wine, including cakes and chocolate, which she ate every day. When the demographers James Vaupel and Bernard Jeune, two of the authors of “Supercentenarians,” visited her at age 120, she remarked that the most important thing in her long life was that “I had fun. I am having fun.”

Chris Mortensen's long life is also detailed in the book. Born in Denmark, he died at 115 in the United States. Still the record holder as the world's oldest living man, at his advanced age he still smoked cigars, and lived as long as the Dutch woman Hendrikje van Andel-Schipper. Despite being born prematurely with a weight of only three pounds, she nevertheless avoided major life-threatening diseases until her nineties, when she was diagnosed with a breast cancer, and ultimately died of stomach cancer. The African American woman Bettie Wilson who died at the age of 115 even survived a gall bladder surgery at age 114. And Elizabeth Bolden, also an African American woman, who was deeply religious and had ten great-great-great grandchildren, was allegedly completely mentally fit and was able to recount all the major details of her life on her 112th birthday.

What is striking is that many of the super old avoided dementia, at least until shortly before they died. Now researchers want to expand the use of the International Database on Longevity (IDL) and use its data to investigate mortality at advanced age and the reasons for an extra long life. But these reasons are still elusive. So far the only thing for certain is that being a woman is clearly advantageous, since ninety percent of those celebrating their 115th birthday were women. Having ancestors who lived exceptionally long played as little a role as economic background and half of the supercentenarians had no children. It is unclear, however, whether this evidence will remain constant with future supercentenarians. The search for the secret of super old age has only just begun.

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Popular Fruit and Veg Not The Healthiest

Obvious choices of fruit and vegetables are not necessarily the healthiest, new research has suggested. Scientists have come up with a list of five “powerhouse” foods that may be better alternatives. Experts recommend five portions a day of fruit and veg in a healthy diet – plant foods are known to contain “phytonutrient” chemicals that can protect the heart and arteries and prevent cancers – but the most popular varieties may not be the best, according to US researchers.

Scientists analysed data from US health surveys of people's dietary habits to examine sources of phytonutrients. They found that for 10 of the 14 phytonutrients studied, a single food type accounted for two-thirds or more of an individual's consumption. It made no difference whether or not a person was a high or low consumer of fruit and veg.

The most common food sources for five key phytonutrients were: carrots (beta-carotene), oranges / orange juice (beta-cryptoxanthin), spinach (lutein/zeaxanthin), strawberries (ellagic acid) and mustard (isothiocyanates).

However, for each of these phytonutrients there was a better food source available.

These were listed as follows: sweet potatoes (nearly double the beta-carotene of carrots), papaya (15 times more beta-cryptoxanthin than oranges), kale (three times more lutein/zeaxanthin than spinach), raspberries (three times more ellagic acid than strawberries), and watercress (one cup contains as much isothiocyanate as four teaspoonfuls of mustard)

Study leader Keith Randolph, technology strategist for the supplement company Nutrilite, said: “These data highlight the importance of not only the quantity but also the significant impact the quality and variety of the fruits and vegetables you eat can have on your health.”

The findings were presented at the 2010 Experimental Biology conference in Anaheim, California.

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12 Ways Vitamin D Can Help

Vitamin D, the “sunshine” vitamin, does a lot more than help keep bones strong — scientists are finding that it impacts all aspects of our health.

Vitamin D can be obtained from exposure to sunlight, vitamin supplements (vitamin D-3 is recommended by many experts), and foods such as salmon and tuna.

Recent studies show that having high levels of vitamin D in our blood can help protect against many diseases, while low levels are linked with several disorders.

Here are 12 critically important ways vitamin D can help protect your health:

1. Colon cancer. A study by cancer prevention specialists at the Moores Cancer Center at the University of California found that high amounts of vitamin D could slash colorectal cancer rates by two-thirds. A European study found that high levels of vitamin D cut the odds of colon cancer by almost 40 percent.

2. Breast cancer. Research using data from two earlier studies found that women with the highest amounts of vitamin D in their blood lowered their risk of breast cancer by 50 percent when compared to women with the lowest levels. A Canadian study found that women who took a vitamin D pill of least 400 international units every day lowered their risk of developing breast cancer by 24 percent.

3. Heart disease. A British study has found that middle-aged and elderly people with high levels of vitamin D reduce their risk of developing cardiovascular disease by 33 percent. Utah scientists found that patients who raised their blood levels of vitamin D after being diagnosed as deficient lowered their risk of having a heart attack by 33 percent, their risk of heart failure by 20 percent, and their risk of dying from any cause by 30 percent.

4. Brain health. A European study of men between the ages of 40 and 79 found that high levels of vitamin D were associated with high scores on memory tests.

5. Diabetes. Researchers at Warwick Medical School found that adults with the highest blood levels of vitamin D lowered their risk of developing Type 2 diabetes by 55 percent.

6. Asthma. Asthmatics who have high levels of vitamin D have better lung function and respond to treatment better than those who have low levels, according to researchers at National Jewish Health in Denver.

7. Bone health. Vitamin D and calcium reduce the risk of hip fractures in the elderly. Studies show that people who are deficient in vitamin D absorb 65 percent less calcium than those with normal levels. One recent study from the United Kingdom found that 95 percent of patients with hip fractures were deficient in vitamin D, and having adequate levels could reduce hip fractures by up to 50 percent.

8. Depression. University of Toronto researchers found that people who suffer from depression, especially those with seasonal affective disorder, improved as the levels of vitamin D in the blood rose. Researchers in Norway found that high doses of vitamin D helped relieve the symptoms of depression.

9. Multiple sclerosis. Australian scientists discovered that people who live in the state furthest from the equator — and get less sunlight — are seven times more likely to develop multiple sclerosis than those who live in the sunniest state.

10. Colds and flu. Scientists at the University of Colorado found that people with the lowest amounts of vitamin D in their blood had the highest incidence of colds and flu.

11. Rheumatoid arthritis. Researchers from the University of Alabama, Birmingham, found that women with the highest levels of vitamin D in their blood lowered their chances of developing rheumatoid arthritis by 30 percent.

12. Crohn's Disease. Vitamin D switches on genes responsible for fighting Crohn's disease (a chronic inflammatory disease primarily affecting the small and large intestine), according to Canadian researchers. “Our data suggests that vitamin D deficiency can contribute to Crohn's disease,” Dr. John White, endocrinologist at the Research Institute of the McGill University Health Center in Montreal, Canada, said in a statement.

(Source: National Institute of Health UK)

 

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