Drinking soft drinks is associated with higher blood pressure, according to a study of over 2,500 people reported this week in the journal Hypertension. High blood pressure is a major risk factor for heart disease, which is the leading cause of death worldwide. Someone with a blood pressure level in millimetres of mercury (mmHg) of 135 over 85 is twice as likely to have a heart attack or stroke as someone with a reading of 115 over 75.
The new research shows that for every extra can of soft drink consumed per day, participants on average had a higher systolic blood pressure by 1.6 mmHg and a higher diastolic blood pressure by 0.8 mmHg. This difference was statistically significant even after adjusting for factors such as weight and height. The study did not examine the mechanism that might link soft drinks with blood pressure. However, the researchers suggest that raised uric acid, which has been linked to soft drink consumption, might raise blood pressure by reducing the levels of nitric oxide, a chemical that relaxes the lining of the blood vessels.
The association between soft drinks and higher blood pressure was especially strong in people who consumed a lot of salt as well as sugar. Diet drinks were linked with lower blood pressure levels in some analyses, but the association was not consistent or strong. Professor Paul Elliott, senior author of the study, from the School of Public Health at Imperial College London, said: “It’s widely known that if you have too much salt in your diet, you’re more likely to develop high blood pressure. The results of this study suggest that people should be careful about how much sugar they consume as well.”
The researchers analysed data from 2,696 volunteers aged between 40 and 59, in eight areas of the US and two areas of the UK. On four separate occasions over a period of three weeks on average, the participants reported what they had eaten in the preceding 24 hours, as well as giving urine samples and having their blood pressure measured. The volunteers were taking part in INTERMAP, the International Study of Macronutrients, Micronutrients and Blood Pressure.
The researchers also found that people who drink more soft drinks tended to have more unhealthy diets in general. As well as consuming more sugar, those consuming more than one soft drink a day consumed more calories by 397 kilocalories per day on average, and less fibre and minerals. Those who did not consume soft drinks had a lower body mass index (BMI) on average than those who consumed more than one drink per day. “Individuals who drink a lot of sugar-sweetened beverages appear to have less healthy diets,” said Dr Ian Brown, the study’s first author, also from the School of Public Health at Imperial College London. “They are consuming empty calories without the nutritional benefits of real food. They consume less potassium, magnesium and calcium.” “This is a population study,” Dr Brown added. “It can’t say definitively that sugary drinks raise your blood pressure, but it’s one piece of the evidence in a jigsaw puzzle that needs to be completed. In the meantime, we would advise people who want to drink sugar-sweetened beverages should do so only in moderation.”
Eating a diet rich in fibre has long been known to help keep your digestive tract working properly. It’s also thought to lower the risk of heart disease, some cancers and diabetes. Now, a new study suggests it could reduce the risk of death from cardiovascular, infectious and respiratory diseases. People who ate a high-fibre diet decreased their risk of dying over a nine year period compared to those who ate less fibre, according to a new study in the Archives of Internal Medicine.
The findings are based on a diet study from the National Institutes of Health and AARP, which included 219,123 men and 168,999 women ages 50 to 71 when the study began. Researchers from the National Cancer Institute examined food surveys completed by the participants in 1995 or 1996. After nine years about 11,000 people died and researchers used national records to determine the cause.
People who ate at least 26 grams per day were 22 percent less likely to die than those who consumed the least amount of fibre — about 13 grams per day or less. Men and women who consumed diets higher in fibre also had a reduced risk of cardiovascular, infectious and respiratory diseases, the study found. Getting fibre from grains seemed to have the biggest impact, the authors write.
The study has some limitations — mainly, people who ate high-fibre diets might also have been more likely to eat healthier diets overall, attributing to their longevity. Still, the study offers more evidence that fibre is certainly good for you. Federal dietary guidelines recommend people consume at least 14 grams of fibre per 1,000 calories, so about 28 grams for an average 2,000 calorie-per-day diet. But many experts say many people don’t get enough.
Women consuming too much red meat may have a higher risk of stroke than women eating less, says a new study. Red meat is high in saturated fat and cholesterol; both are risk factors for cardiovascular disease, heart attack, and stroke. The United States Centers for Disease Control and Prevention suggests lowering saturated fat intake and eating more fresh fruits and vegetables to help reduce your risk of stroke. Writing in the journal Stroke, researchers examined nearly 35,000 Swedish women, ages 39 to 73. None of the women had heart disease prior to the start of the study in 1997.
After ten years, results showed 4% of the study participants, 1,680 women, had a stroke. Those consuming the most red meat had the highest risk of stroke. Women in the top tenth of red meat intake, consuming at least 3.6 ounces each day, were 42% more likely to have a stroke, compared to women who ate just under one ounce of red meat daily.
Eating processed meat also increased stroke risk. Women eating 1.5 ounces of processed meat each day were 24% more likely to suffer a cerebral infarction, compared to woman consuming less than half an ounce of processed meat each day. Processed meat was not linked to any other form of stroke. Cerebral infarction is a type of stroke caused by a disturbance in the blood vessels supplying blood to the brain. Other types of stroke involve a rupturing of a blood vessel, called hemorrhagic strokes.
The scientists blame red meat and processed meat’s effect on raising blood pressure for the increased stroke risk. According to the World Health Organization (WHO), every year an estimated 17 million people die due to cardiovascular diseases, most notably stroke and heart attack. The WHO lists physical inactivity and unhealthy diet as the main risk factors for heart disease and major cardiac events.
Cancer is a leading cause of death around the world. WHO estimates that 84 million people will die of cancer between 2005 and 2015 without intervention. Each year on 4 February, WHO supports International Union Against Cancer to promote ways to ease the global burden of cancer. Preventing cancer and raising quality of life for cancer patients are recurring themes.
Teens whose diets include lots of sugary drinks and foods show physical signs that they are at increased risk for heart disease as adults, researchers from Emory University report. Among 2,157 teens who took part in the National Health and Nutrition Examination Survey, the average amount of added sugar eaten in a day was 119 grams (476 calories), which was 21.4 percent of all the calories these teens consumed daily, the researchers noted. “We need to be aware of sugar consumption,” said lead researcher and postdoctoral fellow Jean Welsh. “It's a significant contributor of calories to our diet and there are these associations that may prove to be very negative,” she said. “Sugar-sweetened soft drinks and sodas are the major contributor of added sugar and are a major source of calories without other important nutrients.” Awareness of the negative effects of added sugar may help people, particularly teens, cut down on the amount of sugar they consume, Welsh added. “Parents and adolescents need to become aware of the amount of added sugar they are consuming and be aware that there may be some negative health implications if not now, then down the line,” she said.
The report is published in the Jan. 10 online edition of Circulation.
Welsh's team found that teens who consumed the most added sugar had 9 percent higher LDL (“bad”) cholesterol levels, and 10 percent higher triglyceride levels (another type of blood fat), compared with those who consumed the least added sugar. Teens who took in the highest amount of added sugar also had lower levels of HDL (“good”) cholesterol than those who consumed the least amount of added sugar. In addition, teens who consumed the highest amount of added sugar showed signs of insulin resistance, which can lead to diabetes and its associated risk of heart disease, the researchers found.
The American Heart Association has recommended an upper limit for added sugars intake, based on the number of calories you need. “Most American women [teens included] should consume no more than 100 calories of added sugars per day; most men, no more than 150 calories,” the association states.
One caveat to these findings is that because of the way the study was done it is not clear if added sugars caused the differing cholesterol levels, only that they are linked. In addition, the data are only for one day and may not reflect the teen's usual diet, the researchers noted. Commenting on the study, Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine, said that “this study does not prove that dietary sugar is a cardiac risk factor in this population, but it strongly suggests it.”
The paper has three important messages, he said. First, dietary sugar intake in a representative population of teenagers is nearly double the recommended level. Second, the higher the intake of sugar, the greater the signs of cardiac risk, including elevated LDL (“bad”) cholesterol and low HDL (“good”) cholesterol. Third, the apparent harms of excess sugar are greater in overweight than in lean adolescents.
“Sugar is by no means the sole dietary threat to the health of adolescents, or adults,” Katz said. “But we now have evidence it certainly counts among the important threats to both. Reducing sugar intake by adolescents, to prevent them becoming adults with diabetes or heart disease, is a legitimate priority in public health nutrition,” he said.
SOURCES: HealthDay; Jean Welsh, M.P.H., Ph.D., R.N., postdoctoral fellow, Emory University, Atlanta; David L. Katz, M.D., M.P.H., director, Prevention Research Center, Yale University School of Medicine, New Haven, Conn.; Jan. 10, 2011, Circulation, online
Japanese women who eat three or more bowls of rice a day face a 50 percent greater risk of developing diabetes than those who eat one bowl, according to research by the National Cancer Center and other institutions. Although it has long been known that consuming large amounts of carbohydrates can increase the risk of developing the disease, the study was the first of its kind to explore the connection between eating rice and developing diabetes.
Conducted over five years from the early 1990s, the study covered about 60,000 people aged 45 to 74 in Iwate, Nagano, Ibaraki, Okinawa and four other prefectures. Of the subjects, 1,103–625 men and 478 women–developed diabetes during the study period.
Women who ate three bowls of rice a day were 1.48 times more likely to develop diabetes than those who ate one serving daily, the study found. Eating four or more bowls of rice a day raised the risk of women developing diabetes to 1.65 times that of women who ate only one bowl of rice a day. However, among women who performed physical labor or exercised vigorously for at least one hour a day, there was no significant difference in their risk of developing diabetes regardless of whether they habitually gorged on the grain.
For men, there was less evidence of a connection between rice intake and diabetes risk.
But regardless of gender, the less physical exercise a person did, the higher their risk of developing the disease.
While it is possible that eating a lot of rice can contribute to the onset of diabetes in some women, the study produced no conclusive evidence that overindulging is a direct cause of diabetes. Researchers at the National Center for Global Health and Medicine who analyzed the study’s results said it was important to monitor rice intake as part of maintaining a balanced diet.
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.
Even young children appear to be consuming more caffeine, so much so that caffeine could be contributing to sleep problems in primary school children, researchers found. Three-quarters of children ages 5 to 12 consumed caffeine on an average day in a survey of parents at routine clinic visits by William J. Warzak, PhD, of the University of Nebraska Medical Center in Omaha, and colleagues. The more caffeine children consumed, the fewer hours they slept on average (P=0.02), the researchers reported online in the Journal of Pediatrics, although not drawing a causal link. The average intake was two or three times higher than the 22- to 23-mg daily average reported nearly a decade ago, they noted.
Eight- to 12-year-olds in Warzak's study averaged 109 mg of caffeine — the equivalent of nearly three 12-oz cans of soda each day. But even the 52 mg of caffeine consumed by 5- to 7-year-olds on an typical day was well above the level known to have a physiologic effect on adults, the researchers noted. “There's really no role for caffeine in kids,” Marcie Schneider, MD, of the Albert Einstein College of Medicine in New York City, emphasized in commenting on the study. “We know that caffeine raises your blood pressure, raises your heart rate, and can be addictive.” Unlike older teens who are likely drinking coffee to wake up in the mornings for school, the assumption is that younger kids are getting most of their caffeine from soda, noted Schneider, who serves as a member of the American Academy of Pediatrics Committee on Nutrition.
She urged pediatricians to raise parents' awareness of the issue, perhaps as part of the yearly checkup. “We routinely ask kids what they're eating and drinking,” “It may be something that is worth pediatricians pointing out to parents that this kid does not need caffeine in their life partially because it does some things that are negative.”
Warzak's group surveyed parents of 228 children seen at an urban outpatient pediatric clinic during routine visits about the children's average daily consumption of drinks and snacks with an emphasis on caffeine-containing items. None of the children had a known sleep disorder or medical condition that might cause bedwetting. Illustrated depictions were provided to help parents accurately estimate serving sizes.
Nearly all of the caffeine intake was consumed through beverages. Few children got a meaningful amount of caffeine from food. “Caffeine's diuretic properties have encouraged behavioral health practitioners to eliminate caffeine from the diet of children with enuresis,” the researchers noted. However, they found that intake didn't correlate with the number of nights a child wet the bed (P=0.49). Overall, enuresis was actually less likely in children who consumed caffeine.
The researchers cautioned that interpretation of these results may be complicated by cultural differences in reporting children's behavioral health concerns and that their study could not draw any causal conclusions. Schneider also noted the use of parental reports and the relatively small sample as limitations. Although the findings offered no support for removing caffeine from children's diets on the basis of bedwetting, Warzak's group concluded in the paper that “given the potential effects of caffeine on childhood behavior, a screen of caffeine consumption might be beneficial when evaluating childhood behavioral health concerns.”
Source: Warzak WJ, et al “Caffeine consumption in young children” J Pediatr 2011; DOI: 10.1016/j.jpeds.2010.11.022.
Researchers from the University of Hull and the Hull York Medical School have found dark chocolate has a significant effect on reducing the symptoms of Chronic Fatigue Syndrome (CFS). The research, published in Nutrition Journal, found that polyphenol rich chocolate eases the condition, with subjects noting significant improvements to their well-being. Chocolate is known to increase neurotransmitters like phenyl ethylamine, serotonin, and anandamide in the brain, but this is the first time that polyphenol rich chocolate in people with CFS has been studied.
Above: Professor Steve Atkin.
Subjects with CFS having severe fatigue of at least 10 out of 11 on Chalder Fatigue Scale were enrolled on the pilot study. Participants were given one of two types of chocolate, one with a high cocoa content and the other without.
Over an eight week period the volunteers consumed one type of chocolate followed by a two week wash out period and then another eight weeks of eating the other variety. The dark chocolate contained 85% cocoa solids with the alternative containing none. Each individual bar weighed 15g with each volunteer expected to eat three per day, and also told not to consume more or make changes to their diet.
Researchers also noted the weight of subject did not significantly alter despite consuming an extra 245 calories per day for two months.
Professor Steve Atkin who led the study says: “The significance of the results is particularly surprising because of the small number of subjects in the study. A further study is needed to see what the effects would be on a larger group of people, but this is potentially very encouraging news for those who suffer from Chronic Fatigue Syndrome.”
This latest finding follows recent research also carried out at the University of Hull and the Hull York Medical School where dark chocolate was found to help reduce the risk of heart attacks in people with Type 2 diabetes by increasing the amount of good cholesterol in the blood stream.
A new study finds that drinking orange juice, soda and other beverages high in the sugar fructose could increase the small risk that middle-age and elderly women have of developing gout. Gout is a painful form of arthritis caused by too much uric acid in the blood. For women in the study who drank two or more servings of these beverages per day, the risk of gout was more than double that for women who drank sugary sodas and juices less than once per month. Because gout is relatively rare among women, the drinks probably contribute only moderately to a woman's chances of developing it. Still, this is the first study linking sodas and sweetened fruit juices to women's gout risk. Previous research found such a link for men.
The study will be published in the Nov. 24 issue of the Journal of the American Medical Association, and is being presented today (Nov. 10) at the American College of Rheumatology annual scientific meeting.
Gout occurs when levels of uric acid in the blood become too high, and uric acid crystallizes around the joints, leading to inflammation, swelling and pain. Foods than can increase the levels of uric acid in the blood include organ meats (such as kidneys and livers), asparagus and mushrooms, according to the Mayo Clinic. Fructose is also known to increase blood uric acid levels, the researchers said. While gout is not common in the United States, the rate of incidences has more than doubled over a 20-year period, from 16 cases per 100,000 Americans in 1977 to 42 per 100,000 in 1996. Over this period, the researchers noted, the population also consumed increasing amounts of soda and other drinks sweetened with fructose.
The new study followed 78,906 women for 22 years, from 1984 to 2006, as part of the Nurses' Health Study. At the beginning of the study, none of the women had gout. By the end, 778 had developed it. Women who drank one serving of soda per day were 1.74 times more likely to develop gout than those who drank less than one serving per month. Those who drank two or more servings per day were 2.4 times more likely to develop gout. Drinking two or more servings of soda per day caused an additional 68 cases of gout per 100,000 women per year, compared with drinking less than one serving of soda per month, the researchers said. Drinking orange juice also increased the risk. Women who drank one serving of orange juice per day were 1.41 times more likely to develop gout, and those who drank two or more servings were 2.4 times more likely to report gout.
Lifestyle and diet
The rise in gout cases is most likely due to changes in lifestyle and diet and an increase in conditions associated with gout, such as metabolic syndrome, said study researcher Dr. Hyon K. Choi of the Boston University School of Medicine. The results held even after the researchers took into account factors that could have influenced the findings, such as age, body mass index and whether the women had gone through menopause, Choi said.
The findings suggest diets to prevent gout should reduce fructose intake, the researchers said.
The study was funded by the National Institutes of Health.