It's no secret that eating well is good for both body and mind, so it may not come as a surprise that a new study finds women who eat more olive oil and leafy vegetables such as salads and cooked spinach are significantly less likely to develop heart disease.A group of Italian researchers found that women who ate at least 1 serving of leafy vegetables per day were more than 40 percent less likely to develop heart disease over an average of eight years, relative to women who ate two or fewer portions of those vegetables each week. Women who downed at least 3 tablespoons of olive oil daily – such as in salad dressing – were also 40 percent less likely to be diagnosed with heart disease, compared to women who ate the least olive oil.
It's not exactly clear why specifically leafy vegetables and olive oil may protect the heart, said study author Dr. Domenico Palli of the Cancer Research and Prevention Institute in Florence. “Probably the mechanisms responsible for the protective effect of plant-origin foods on cardiovascular diseases involve micronutrients such as folate, antioxidant vitamins and potassium, all present in green leafy vegetables.” Folate reduces blood levels of homocysteine, Palli explained, which is thought to increase the risk of cardiovascular disease by damaging the inner lining of arteries. Other studies have shown people who eat more potassium have lower blood pressure, which can protect the cardiovascular system. Virgin olive oil may be particularly effective at lowering heart disease risk because of its high level of antioxidant plant compounds, he added.
This is not the first study to link olive oil or vegetables to good heart health. Most famously, the traditional Mediterranean diet — rich in vegetables and monounsaturated fats from olive oil and nuts, but low in saturated fat from meat and dairy — has been tied to a decreased risk of heart disease. Mediterranean-style eating has also been credited with lowering risk for some cancers, diabetes, and, more recently, with slowing brain aging. Cardiovascular disease is a major killer, responsible for 30 percent of all deaths worldwide and the leading cause of death for both men and women in the U.S.
To look more closely at the role of foods in protecting against heart disease, Palli and colleagues reviewed dietary information collected from nearly 30,000 Italian women participating in a large national health study. Researchers followed the women, whose mean age was 50 at the beginning of the study, for an average of 8 years, noting who developed heart disease. In that time, the women experienced 144 major heart disease-related events, such as heart attack or bypass surgery, the authors report in the American Journal of Clinical Nutrition. Women who ate at least one daily serving (about two ounces) of leafy vegetables – such as raw lettuce or endives, or cooked vegetables like spinach or chard — had a 46 percent lower risk of developing heart disease than women who ate at most two portions per week. Consuming at least an ounce of olive oil per day lowered their risk by 44 percent relative to women who consumed a half-ounce or less daily, the authors found.
The women's intake of other types of vegetables, such as roots and cabbages, and their consumption of tomatoes or fruit did not seem to be linked to their risk for major heart events. Both fruits and vegetables have been associated with heart benefits in past studies conducted elsewhere in Europe and in North America. The authors caution that the apparent lack of positive effect from high fruit consumption in their results may have something to do with a different attitude toward fruit in Italy. It is cheap, varied and easily available, so eating a lot of fruit is a widespread habit but it does not necessarily signal that the rest of someone's diet is as healthy, the authors wrote. Another issue with the study, Palli noted, is that women had to report how much they ate of various items, and some may not have remembered their diets accurately, or may have changed their eating habits during the study period. In addition, people sometimes over-estimate their healthy behaviors, believing they eat healthier than they really do.
SOURCE: American Journal of Clinical Nutrition, published online December 22, 2010.
Eating more fruits and vegetables may not protect children from developing allergies, according to a large Swedish study that questions earlier hints of benefit. Fruits and vegetables are rich in antioxidants, which are thought to reduce airway inflammation. So recent studies reporting less asthma, wheezing and hay fever among children who consumed more produce appeared to make sense.
But not all research has found that link, and the studies that did may have had a surprising flaw, said Helen Rosenlund of Karolinska Institutet in Stockholm, who led the new study. She said some proteins in fruits like apples and pears resemble the pollen parts that trigger hay fever, meaning that kids might react to both. In other words, existing allergies may have caused them to eat around the produce, rather than the other way around. “This could confuse research findings,” explained Rosenlund, “falsely suggesting that diets with fewer fruits and vegetables result in more allergic disease.”
To find out if this was the case, Rosenlund and her colleagues looked at data on nearly 2,500 eight-year-olds who had participated since birth in a larger Swedish study. Based on blood tests and questionnaires filled out by parents, the researchers found that seven percent of the children had asthma. The rates of hay fever and skin rashes were more than twice as high. The average child ate between one and two servings of fruit, and between two and three servings of vegetables each day.
At first glance, some produce did seem helpful: Kids with the biggest appetite for fruit had less than two-thirds the odds of developing hay fever than those who ate the least amount. Apples, pears and carrots appeared to be particularly helpful, the researchers report in the Journal of Allergy and Clinical Immunology, but there was no such link for vegetables overall. However, it turned out that half the children with hay fever were sensitive to birch tree pollen, one of the pollens known to resemble the proteins in apples and carrots. And sure enough, after the team repeated their analysis excluding the 122 kids with food-related allergy symptoms, the hay fever link disappeared as well. “Fruits do not seem to offer protection against allergic if diet modifications are considered,” say Rosenlund.
The researchers say more studies are needed, particularly in other parts of the world that may have a different variety of allergy triggers, or allergens. And they advise those studies should not forget to look at how allergies might influence what participants eat. “Studying diet it is not so easy when it comes to the relation with allergic disease,” Rosenlund said, “because it is such a complex disease pattern.”
SOURCE: bit.ly/g3DpI7 The Journal of Allergy and Clinical Immunology, online January 10, 2011.
A new study shows following a Mediterranean style diet rich in vegetables, olive oil, and fish may keep the mind sharp and slow age-related cognitive decline.The diet typified by the Italians, Greeks, and other Mediterranean cultures has already been shown to reduce the risk of heart disease, diabetes, and some types of cancer. But this and other studies are now suggesting that the diet may also have healthy benefits for the mind.
The Mediterranean diet emphasizes fruits and vegetables, fish, legumes, non-refined cereals, olive oil, and moderate wine consumption, usually at meals. Researchers found older adults who followed the diet more closely had slower rates of age-related cognitive decline than those who didn't, even after adjusting for other factors such as educational level. “The more we can incorporate vegetables, olive oil, and fish into our diets and moderate wine consumption, the better for our aging brains and bodies,” says Christy Tangney, PhD, associate professor of clinical nutrition at Rush University, in a news release.
In the study, published in the American Journal of Clinical Nutrition, researchers analyzed information gathered by the ongoing Chicago Health and Aging Project, which follows 3,759 adults over the age of 65 living on the South Side of Chicago. Every three years, the participants took tests of memory and basic math skills and filled out a questionnaire on how often they eat 139 different foods. The study follow-up time was 7.6 years on average.
Researchers looked at how closely the participants followed a Mediterranean diet and then compared it to their scores on age-related cognitive decline. Out of a maximum score of 55 for total adherence to a Mediterranean diet, the average score was 28. The results showed those with higher than average scores had a slower rate of age-related mental decline than those with lower scores. Researchers also looked at how closely the participants followed the Healthy Eating Index-2005, which is based on the 2005 Dietary Guidelines for Americans. They found no relationship between adherence to this type of diet and the rate of age-related cognitive decline.
Primary school children who don't like eating fruit and vegetables are 13 times more likely to develop functional constipation than children who do, according to a study in the December issue of the Journal of Clinical Nursing. Drinking less than 400ml of fluid a day also significantly increases the risk. Dr Moon Fai Chan, assistant professor at the National University of Singapore, teamed up with Yuk Ling Chan, from the Hong Kong Polytechnic University, to study the diet and toileting habits of 383 children aged from eight to ten from a school in Hong Kong. Fifty-one per cent were boys and children who were on regular medication or who paid regular hospital or clinic visits were excluded. Seventy per cent of the children who took part in the study were ten-years-old, 22 per cent were nine and eight per cent were eight.
“A number of studies have suggested that functional constipation – which is due to dietary habits, environmental habits and psychosocial factors rather than a particular health problem – is getting worse among school-age children” says Dr Moon Fai Chan from the Alice Lee Centre for Nursing Study at the University. “It is estimated that functional constipation accounts for 95 per cent of cases of constipation affecting children once they pass infancy. The condition has serious consequences, as it can cause a wide range of distressing emotional and physical problems such as stress, soiling, problems at school, damaged self-confidence and reduced social interaction.”
Key findings of the study included:
- Seven per cent of the children who took part suffered from functional constipation and there were clear dietary differences between the children who did and did not have problems.
- Girls were more likely to have functional constipation than boys (8.2 per cent versus 6.6 per cent) and nine-year-olds were more likely to report problems (13.3 per cent) than eight-year-olds (10 per cent) and ten-year-olds (5.2 per cent).
- Children who only drank 200ml to 400ml of fluid a day were eight times more likely to experience problems than children who drank 600ml to 800ml and 14 times more likely than children who drank a litre or more.
- Children who said they did not like fruit or vegetables were 13 times more likely to suffer from functional constipation than children who did.
- Nine out of ten children refused to use the school toilets for bowel movements and the figure was the same for children with and without constipation.
The biggest problems with school toilets were that children preferred to go at home. They also cited lack of toilet paper and dirty toilets. “When we compared our findings with previous studies we found that the levels of functional constipation among Hong Kong school children was higher than those in the USA and UK, but similar to Italy” says Dr Chan. The authors have made a number of recommendations that they feel would help to tackle the problem. They suggest that:
- Primary schools should work with healthcare professionals to make children more aware of the problem, with regular healthcare education sessions in classrooms and at assemblies.
- Parents need to be educated about functional constipation so that they can spot problems in their children and make sure that their diet provides sufficient fluid, vegetables and fruit. They should also remind their children to pay regular toilet visits at school.
- School tuck-shops should stock high-fibre snacks such as popcorn, fresh food and dried fruit, instead of crisps and sweets.
- Children should be encouraged to drink plain water during lessons and drinking fountains should be installed.
- School toilets should be more user-friendly, private and well stocked with paper so that children feel more comfortable using them.
“We hope that this study will help to raise awareness of functional constipation, which can cause children real physical and emotional distress and seriously affect their quality of life” says Dr Chan.
Source: Investigating factors associated with functional constipation of primary school children in Hong Kong. Chan MF and Chan YL. Journal of Clinical Nursing. 19, pp3390-3400. (December 2010). DOI: 10.1111/j.1365-2702.2010.03366.x
Two specific eating patterns increase the risk of death for older adults, a 10-year study finds.Compared to people who ate healthy foods, men and women in their 70s had a 40% higher risk of death if they got most of their calories from high-fat dairy foods or from sweets and desserts. University of Maryland researcher Amy L. Anderson, PhD, and colleagues monitored the eating patterns of 2,582 adults aged 70 to 79. They found that these diets fell into six patterns or clusters.
After adjusting for risk factors such as sex, age, race, education, physical activity, smoking, and total calories, “the High-Fat Dairy Products cluster and the Sweets and Desserts cluster still showed significantly higher risk of mortality than the Healthy Foods cluster,” Anderson and colleagues found.
The six dietary patterns were:
- Healthy Foods: Higher intake of low-fat dairy products, fruit, whole grains, poultry, fish, and vegetables. Lower intake of meat, fried foods, sweets, high-energy drinks, and added fat.
- High-Fat Dairy Products: Higher intake of ice cream, cheese, and 2% and whole milk and yogurt. Lower intake of poultry, low-fat dairy products, rice, and pasta.
- Sweets and Desserts: Higher intake of doughnuts, cake, cookies, pudding, chocolate, and candy. Lower intake of fruit, fish and other seafood, and dark green vegetables.
- Meat, Fried Foods, and Alcohol: Higher intake of beer, liquor, fried chicken, mayonnaise/salad dressings, high-energy density drinks, nuts, snacks, rice/pasta dishes, and added fat. Lower intake of low-fat dairy products, fiber/bran breakfast cereal, and other breakfast cereal.
- Breakfast Cereal: Higher intake of fiber/bran and other breakfast cereals (especially the latter). Low intake of nuts, refined grains, dark yellow vegetables, and dark green vegetables.
- Refined Grains: Higher intake of refined grains (such as pancakes, waffles, breads, muffins, and cooked cereals such as oatmeal) and processed meat (such as bacon, sausage, ham, and other lunchmeats). Lower intake of liquor, breakfast cereals, and whole grains.
Several of the groups got an unusually large amount of their total calories from just one food group:
The sweets and desserts cluster got 25.8% of its total energy from sweets.The refined grains cluster got 24.6% of its total energy from refined grains.The breakfast cereal group got 19.3% of its total energy from cold cereals other than those full of fiber and bran.The high-fat dairy products group got 17.1% of its total energy from higher-fat dairy foods.
Overall, people in the healthy foods cluster had more years of healthy life and a lower death rate than all other groups. Moreover, their blood tests came back with significantly more indicators of health than the other groups.
But not all of the study findings were so predictable. “Unexpectedly, in this and in several other studies, a [dietary] pattern higher in red meat was not significantly associated with increased risk of mortality,” Anderson and colleagues note. It's also not entirely clear why the Meat, Fried Food, and Alcohol cluster didn't have a significantly higher death risk, as most diets warn people to limit or avoid such foods.
“In our study, the Meat, Fried Food, and Alcohol cluster did have a slightly higher percentage of total energy from vegetables, fruit, and whole grains than both the High-Fat Dairy Products and Sweets and Desserts clusters, which showed higher risk of mortality,” Anderson and colleagues suggest.
This was by far the most common eating pattern seen in the study: 27% of participants were in the meat, fried food, and alcohol cluster. But Anderson and colleagues do not recommend such a diet. Instead, they point to the fact that 14.5% of study participants were in the healthy foods cluster. “Adherence to such a diet appears a feasible and realistic recommendation for potentially improved survival and quality of life in the growing older adult population,” Anderson and colleagues conclude.
The study appears in the January 2011 issue of the Journal of the American Dietetic Association.
What did the research involve?
The researchers needed to obtain several sets of data to fill their model. Data for UK deaths from coronary heart disease, stroke and cancer were obtained from the Office for National Statistics, the General Register Office for Scotland and the Northern Ireland Statistics and Research Agency. Information on the population's intake of foods and nutrients was obtained from two sources: the average intake of fatty acids, fibre, and fruit and vegetables for 2005–7 was derived from the Expenditure and Food Survey, while estimates of salt intake came from the National Diet and Nutrition Survey, 2006.
The modelling also incorporated several meta-analyses of individual studies looking at diet and disease risk factors. The researchers looked at reviews that had pooled data from randomised trials, cohort studies or case-control studies, giving priority to meta-analyses of randomised trials. These different studies were combined in the model to calculate the change in risk of disease for an individual who changes his or her diet. To estimate the change in health outcomes with a change in diet at a population level, the model used the difference between current average consumption levels and recommended levels of different foods in the UK.
What were the basic results?
In a general summary of the main findings, the researchers calculated that:
About 33,000 deaths a year would be avoided if UK dietary recommendations were met. There would be a reduction in deaths from coronary heart disease of 20,800 (95% credible interval 17,845 to 24,069), a reduction of 5,876 for deaths from stroke (3,856 to 7,364) and a reduction of 6,481 for deaths from cancer (4,487 to 8,353). About 12,500 of these avoided deaths would be in people aged 75 or under. About 18,000 of the avoided deaths would be men and 15,000 would be women. More than 15,000 of the avoided deaths (nearly half the total figure) would be due to increased consumption of fruit and vegetables. Reducing average salt intake to 6g a day would avoid 7,500 deaths annually. The greatest number of deaths avoided would be in Northern Ireland and Scotland, whose populations are furthest from achieving dietary recommendations.
How did the researchers interpret the results?
The researchers say their study suggests that increasing average consumption of fruits and vegetables to five portions a day is the target likely to offer most benefit in terms of deaths avoided. They also say that reducing recommended salt levels to 3g daily and saturated fat to 3% of total energy would achieve a similar reduction in mortality.
They conclude that their calculations based on the Dietron model are robust, pointing out that their estimate of deaths avoided is lower than a previous government survey which calculated that 70,000 deaths a year could be avoided if government dietary recommendations were met. The estimates could be used in calculating the allocation of resources for interventions aimed at reducing chronic disease.
This well-conducted modelling study used various data sources to link consumption of different dietary components with disease risk factors (for example blood pressure, cholesterol and obesity) and subsequent mortality from coronary heart disease, stroke and cancer. The study supports previous research showing that diet plays a crucial role in health and that a diet with plenty of fruit and vegetables, fibre and low fat and salt levels can reduce the risk of chronic disease, in particular coronary heart disease. However, its predictions are made at the population level. A model such as this cannot predict individual risk, which will depend on many factors, including family history, smoking and other lifestyle habits.
It is important to note that the figures are based on the estimates and assumptions made when using a mathematical model, and not on reality. As the authors themselves note, the modelling technique they used may have led to “some degree of double counting” and that, therefore, their estimate of reduced mortalities if dietary recommendations were met is likely to be an overestimate. Also, the accuracy of the model depends to some extent on the quality of the meta-analyses that were included, and the quality of the individual studies that were pooled within these reviews in order to establish associations between diet and particular disease risk factors.
Overall, this study supports current dietary recommendations and even though it cannot predict how diet influences risk for individuals, it does indicate that keeping to dietary recommendations reduces the risk of disease.
Dietary recommendations include eating five portions of fruit and vegetables a day (about 440g) and 18g of fibre (provided by wholegrain foods and some fruit and vegetables). It is recommended that salt intake is limited to a maximum of 6g a day and that a third of total energy is provided by fats, with saturated fat comprising 10%. The researchers point out that in 2007, according to the estimated average intakes in the sources they used, none of the UK countries met these recommendations.
Research by the University of Reading has found that couples with children have a poorer diet than those without. On average, statistics showed that childless couples ate 2kg more fruit and vegetables than families over a fortnight. The results formed part of a study that looked at the uneven distribution of unhealthy diets in the population. It also showed that regional variation in the demand for fruit and vegetables is pronounced, with the highest demand in London and the South East and the lowest in Scotland and Northern Ireland.
Professor Richard Tiffin, Director of the Centre for Food Security at the University, said: “There are clear distributional implications for dietary health that arise from these patterns of consumption and also for the health of children. They suggest that targeted interventions are necessary in order to reduce the incidence of diet-related health problems in the future.” The study revealed that the presence of children in a household leads to a lower level of demand for fruit and vegetables and meat, and an increased demand for milk and dairy, cereals and potatoes.
The results also emphasised the role played by low incomes and socio-economic circumstances in poor dietary choices. Comparing an unemployed individual with an otherwise identical individual living in a household of two, the former consumed over 3kg less fruit over a period of two weeks. Similarly, for two identical households, a difference in income of 10 per cent can be expected to lead to a difference in demand for fruit and vegetables of around 500g.
Professor Tiffin said: “Our results imply that households which have a higher level of expenditure will tend to consume proportionately more meat and more fresh fruit and vegetables. Households in London and the South East have higher levels of fruit and vegetable consumption while it is reduced by the presence of children. “The dietary components that we have analysed have important implications for policy-makers in tackling diet-related chronic disease, which represents one of the most significant public health challenges of the 21st century.”
The paper, 'The demand for a healthy diet: estimating the almost ideal demand system with infrequency of purchase, by R. Tiffin (University of Reading) and M. Arnoult (Scottish Agricultural College), is published this month in The European Review of Agricultural Economics – http://erae.oxfordjournals.org/content/current
Researchers used the UK government's Expenditure and Food Survey (EFS) for 2003-2004. Participating households voluntarily record food purchases for consumption at home for a two-week period using a food diary. The sample is based on 7,014 households in 672 postcode sectors stratified by Government Office Region, socioeconomic group and car ownership. It is carried out throughout the UK and throughout the year in order to capture seasonal variations.
Bouhlal and co workers reported that salt had an impact on intake but fat did not. They found that in general food intake increased with salt level, noting that compared with the 'normal' salt levels, a suppression of salt induced a 25 per cent decrease in green bean intake, whereas an addition of salt induced a 15 per cent increase in pasta intake. Contrarily to initial beliefs, the researchers observed no increase in food intake with increasing added sugar level. They said the findings indicate that two to three year old children's food intake may not be affected by its added sugar content.
The study data also showed that preschool children with a higher BMI score consumed more pasta when fat level was higher. The authors said this finding may confirm previous results which highlight fatter children prefer high-fat foods. The researcher said their results imply that fat and sugar addition could be avoided in foods for children without having an impact on palatability, allowing the energy density of children's diet to be limited.
“Furthermore, these findings suggest that there is no need to add salt to pasta which is consumed anyway. On the contrary, salt suppression in vegetables, whose intake is to be promoted, should be considered cautiously,” they said.
Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114510003752
“The impact of salt, fat and sugar levels on toddler food intake”
Authors: S. Bouhlal, S. Issanchou, S. Nicklaus
This month the federal Department of Agriculture and Health and Human Services will release the 2010 dietary guidelines. These guidelines directly impact the eating habits of one in every four Americans whose meals are subsidized by federal programs. The precise timing of the release this month is unknown, according to John Webster, a spokesman for the USDA.
The major question here is whether or not the new guidelines will impact the obesity epidemic that is increasing ever so quickly in our country. Decisions about what to eat are generally made at the supermarket, not while reading federal guidelines. “What we need to do is put more effort into figuring out how to engage people who don’t use nutrition as a major deciding point when buying food,” says Alice H. Lichtenstein, a professor at the Friedman School of Nutrition Science and Policy at Tufts University. “We really need to learn more about consumer behavior.’’ Some experts wonder if more nutrition information helps or confuses shoppers.
It is arguable that the guidance needs to be much clearer, more like the wildly popular “Eat This, Not That!,’’ a magazine column, which was then reworked into a book and an iPhone app, that made its mark by telling readers which fast food was nutritionally better than others. Dr. David L. Katz, director of Yale University’s Prevention Research Center and an associate professor at the university’s School of Medicine, is an advocate for more specific guidance. For example, 45 to 65 percent of daily calories should come from foods that contain carbohydrates. But “lollipops and lentils are both carbs,’’ Katz says. And while the current federal recommendations do stress eating carbohydrates from whole grains, fruits, and vegetables, he adds, “We need to do a better job of specifically defining highly recommended foods.’’
While no one is talking about the final 2010 recommendations before their release, a June advisory report, open for public comment, gives some clues. Cohen of UMass Amherst expects the final guidelines to place even greater emphasis on physical activity and continue to recommend that people include more fruits, vegetables, nuts, seeds, foods with Omega-3 fatty acids, and a suggestion to eat three servings of low-calorie dairy products a day (some argue that calcium supplements should be used in place of the third serving).
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.”