NEWS BRIEFS – November 2014
Curcumin, the medicinal compound that gives turmeric its lovely colour, has antidepressant benefits.
CURCUMIN EFFECTIVE AGAINST DEPRESSION
A research trial has found that curcumin, the medicinal compound that gives turmeric its distinctive colour, has significant antidepressant benefits. In a study of 56 volunteers with a major depressive disorder, half were treated with a patented curcumin extract of 500 mg twice daily, while the other half took a placebo, for eight weeks. From weeks four to eight of the study, curcumin was significantly more effective than the placebo in improving several mood-related symptoms in the volunteers.
Previous studies had found strong links between depression and inflammation in the body, and further discovered that curcumin influenced several biological mechanisms including a reduction in inflammation. In animal-based studies, curcumin had been consistently shown to have antidepressant effects. This is the longest such human study that was double-blind and placebo-controlled. These findings support earlier research suggesting that depression is associated with increased inflammation and is not only about brain chemicals such as serotonin. The researchers stressed that they would not recommend it as a first line of treatment for depression yet, because more research is required.
This study was published in the Oct. 1, 2014 issue of Journal of Affective Disorders, accessed at: https://tinyurl.com/osg8yjq with a fee.
TIME SPENT SITTING THREATENS AGING DNA AND LIFE SPAN
A study has found that curbing the amount of time spent sitting down might help to protect aging DNA, and therefore may extend lifespan. Reducing sedentary activity appears to lengthen telomeres, which sit on the end of chromosomes, the DNA storage units in each cell. (Telomeres are important because they stop chromosomes from fraying or clumping together and scrambling the genetic codes they contain, performing an anti-fraying role similar to the plastic tips on the end of shoelaces. Longevity and a healthy lifestyle have been linked to telomere length, but whether physical activity can make any difference has not been clear.)
The researchers analyzed the length of chromosomal telomeres in the blood cells of 49 predominantly sedentary and overweight people in their late 60s, on two separate occasions, six months apart. Levels of physical activity were assessed, as well as amount of time spent sitting down each day. Neither the number of steps taken daily nor the amount of daily physical activity was significantly associated with telomere length. But a reduction in the amount of time spent sitting down daily was significantly associated with telomere lengthening in blood cells.
The authors concluded that a reduction in sitting hours may be of great importance in preserving DNA integrity. This study was posted online September 3, 2014 in advance of later publication in the British Journal of Sports Medicine. You can read the entire report now at https://tinyurl.com/o6zd247 for a fee.
POTASSIUM CUTS RISK OF STROKE AND DEATH
Investigators have released findings showing that, at least among postmenopausal women, those who eat foods higher in potassium have a lower risk of stroke and of mortality than those who eat less potassium-rich foods. Researchers said more studies are needed to determine whether potassium has the same effects on men and younger people. (Previous studies have shown that potassium consumption may lower blood pressure, but whether potassium intake can help prevent stroke or death has not been clarified. Vegetables such as sweet potato, beet greens, and tomato paste, and foods such as bananas, are rich food sources of potassium. The U.S. Dept. of Agriculture recommends that women eat at least 4,700 mg of potassium daily)
Researchers studied 90,137 postmenopausal women, aged 50 to 79, for an average 11 years. They looked at how much potassium the women consumed, and if they had strokes (including ischemic and hemorrhagic strokes) or died of any reason during the study period. Women in the study were stroke-free at the start and their average daily dietary potassium intake was 2,611 mg. Results of this study were based on potassium from food. The researchers found those who ate the most potassium were 12% less likely to suffer stroke in general and 16% less likely to suffer ischemic stroke than women who ate the least. Women who ate the most potassium were also 10% less likely to die during this period than those who ate the least.
Among women who did not have high blood pressure, those who ate the most potassium had a 27% lower ischemic stroke risk and 21% reduced risk for all stroke types; among women with high blood pressure, those who ate the most potassium had a lower risk of death, but potassium intake did not lower their stroke risk. This suggests that higher dietary potassium intake may be more beneficial before high blood pressure develops.
Researchers did not take sodium intake into consideration, so the potential importance of a balance between sodium and potassium is not clarified by these findings. This study will eventually be published in the journal Circulation. Ahead of that, it was posted on the journal website on September 4, 2014 in its full-text version, which can be read at https://tinyurl.com/ojnrp5f free of charge.
CERTAIN SEDATIVES SUCH AS XANAX MAY RAISE ALZHEIMER’S RISK
Researchers have reported that older adults who habitually use sedatives for anxiety or insomnia may have a heightened risk of developing Alzheimer’s disease. The drugs studied were benzodiazepines, a widely prescribed group of sedatives that includes lorazepam (Ativan), diazepam (Valium) and alprazolam (Xanax). (Older adults commonly take the drugs for anxiety or insomnia, often long-term, despite the fact that guidelines call for only short-term use of the drugs. In 2012, the American Geriatrics Society put benzodiazepines on its list of drugs considered potentially inappropriate for seniors, due to risk of confusion, dizziness, and falls.)
This study was based on prescription records but did not ascertain whether patients ever took the pills. This type of study cannot determine cause-and-effect and can only find an association. People in the early stages of Alzheimer’s can have symptoms such as sleep problems and anxiety, raising the possibility that benzodiazepine use is the result of Alzheimer’s, and not the other way around. The scientists found that people who had been prescribed benzodiazepines for more than three months were 51% more likely to develop Alzheimer’s, compared to people who never used these drugs. The risk was almost doubled if they had taken the medications for more than six months. No association was found when patients were prescribed these drugs for no longer than one month for insomnia, and no more than three months for anxiety symptoms.
This study was posted on the British Medical Journal website on Sept. 9, 2014. It can be accessed at https://tinyurl.com/mdphm43 without charge.
CDC REPORT FINDS EXCESS SODIUM CONSUMPTION IN CHILDREN
A new report from the Centers for Disease Control and Prevention concludes that more than 90% of U.S. children aged 6-18 years eat more sodium than recommended. More than 40% of this sodium intake comes from 10 common types of food. Using data from the CDC 2009-2010 National Health and Nutrition Examination Survey, researchers determined that about 43% of sodium eaten by children comes from the 10 foods they eat most often: pizza, bread and rolls, cold cuts and cured meats, savory snacks, sandwiches, cheese, chicken patties and nuggets and tenders, pasta mixed dishes, Mexican mixed dishes, and soups. Most sodium is from processed and restaurant food, not the salt shaker.
The result, predict the scientists, will be high blood pressure and heart disease for these school-age children in the future. Children 6-18 years eat an average of 3,300 mg of sodium a day. (The 2010 dietary guidelines recommend children eat less than 2,300 mg per day.) Most sodium is already in food before it is purchased or ordered, and before salt is added at the table. About 65% comes from store foods, 13% from fast food and pizza restaurants, and 9% from school cafeteria foods.
The report is detailed in the September 2014 issue of the CDC Journal, Morbidity and Mortality Weekly Report. It can be read online at https://tinyurl.com/pvkd3th free of charge.
VITAMIN E DEFICIENCY FOUND TO BE WIDESPREAD
A new analysis suggests that adequate levels of vitamin E, an essential micronutrient, are especially critical for the very young, the elderly, and women who are or may become pregnant. The scientist conducting this review of prior studies concluded that deficiency occurs with alarming frequency, and the effects of this are less obvious.
The study concluded that inadequate vitamin E is associated with increased infection, anemia, stunting of growth, and poor outcomes during pregnancy for both infant and mother. Also, it concluded that overt deficiency, especially in children, can cause neurological disorders, muscle deterioration, and even cardiomyopathy. Vitamin E supplements do not seem to prevent Alzheimer’s disease, but show benefit in slowing its progression.
This study was published September 15, 2014 in the journal Advances in Nutrition. The full report can be accessed online at https://tinyurl.com/p7wjb5n for a fee.
MENTAL WELL-BEING LINKED TO FRUIT AND VEGETABLE CONSUMPTION
Research focused on mental well-being has found that it was consistently associated with regular fruit and vegetable consumption. Among those who indicated that they ate five or more portions of fruit and vegetables a day, 33.5% were found to have high mental well-being, compared with only 6.8% of those who ate less than one portion of produce daily. Of those with high well-being, 31.4% ate three to four portions daily and 28.4% ate one to two servings a day. Other health-related behaviours were found to be associated with mental well-being, but only smoking and fruit and vegetable consumption were consistently associated in both men and women. Alcohol intake and obesity were not associated with high mental well-being.
These novel findings suggest fruit and vegetable intake may help drive not just physical, but also mental, well-being. (Low mental well-being is strongly linked to mental health problems, but high mental well-being is a state in which people feel good and function well. Optimism, happiness, self-esteem, resilience, and good relationships with others are all part of this state.) It should be noted that this association does not necessarily indicate that mental well-being results from produce intake: mental well-being and fruit and vegetable intake could both be caused by a third factor they have in common, such as a greater dedication to healthy lifestyle, for example.
This report was published September 19, 2014 in BMJ Open. The full-text version of the study can now be viewed online at https://tinyurl.com/kwy5h5a free of charge.
CARDIORESPIRATORY FITNESS DELAYS AGE-ASSOCIATED HIGH BLOOD PRESSURE
A new study has found that, when compared to those with lower fitness levels, men with higher fitness levels experience a delay in the development of hypertension that occurs naturally as men age. (Exercise is well-established as a method to prevent heart disease, and is a component of an overall healthy life, but this study examined whether an improved fitness level delays age-related high blood pressure.) Results reveal that the systolic (upper) number of the blood pressure reading reaches prehypertension levels for men of low fitness levels by the average age of 46; systolic readings for men of high fitness do not reach prehypertension levels until the average age of 54. Diastolic (lower) blood pressure readings for men of low fitness reach prehypertension levels by the average age of 42; diastolic readings for men of high fitness do not reach prehypertension levels until advanced age (around 90).
This implies that improving fitness levels may reduce the overall lifetime duration of elevated blood pressure. To move out of the low fitness category, men should perform 150 minutes of moderate-intensity activity such as brisk walking or jogging weekly. Age-related blood pressure rise was found to have no connection to the percentage of body fat. (Approximately one-third of American adult males have high blood pressure; arterial stiffness is the main factor contributing to age-related hypertension.) The effects of cardiorespiratory fitness on age-associated blood pressure increases among women were not researched but will be at a later time.
This study was published in the September 23, 2014 edition of the Journal of the American College of Cardiology. The full text can be accessed online now at https://tinyurl.com/p9j6eop
ORAL CURCUMIN MAY PROTECT INTESTINAL BARRIER FUNCTION
A new report has found that oral curcumin may be an effective therapy to improve the negative intestinal barrier function changes caused by consuming a high-fat Western diet. A Western diet packed with high-fat, high-cholesterol foods is one of the key factors contributing to the growing obesity epidemic and the rise in cases of metabolic diseases such as Type 2 diabetes, heart disease, and chronic kidney disease among Americans. (It has been known that a Western diet changes the gut bacterial composition leading to an increase in harmful bacteria in the intestines.)
A Western diet affects the intestinal barrier by decreasing the activity of a key enzyme called Intestinal Alkaline Phosphatase which normally detoxifies a bacteria-derived toxin called LPS. With the enzyme decreased, the toxin gets into circulation and causes low-grade inflammation. The new study found that a Western diet also directly affects the intestinal barrier function. Researchers examined the effect of curcumin on intestinal barrier function at the molecular level and in an animal model. They report that oral curcumin reduced the Western diet effect on intestinal barrier function. Also, the study for the first time shows that curcumin does not need to be absorbed to bring about its effects. It had profound effects on the intestinal wall, which effectively reduced inflammation. This in turn helps reduce the development of diabetes and atherosclerosis.
This study was published September 25, 2014 by the journal PLOS ONE. The full report can be read online at https://tinyurl.com/l6yf3nl free of charge.
VITAMIN D MAY INHIBIT AGE-RELATED MEMORY EFFECTS
Scientists have shown that a boosted daily dosage of vitamin D over several months helped middle-aged rats navigate a difficult water maze better than their lower-dosed cohorts. (Medical science has been expanding their reports on vitamin D deficiencies to include higher risks of cancer and cognitive decline in the elderly.) The supplement appears to boost the recycling of signaling chemicals that help neurons communicate with one another in a part of the brain that is central to memory and learning. Neurons also are better able to receive and process those signals in ways that are connected with memory formation and retrieval, the study found. The improvements in memory were associated with a level of a vitamin D metabolite that is about 50% higher than the level recommended by the Institute of Medicine to maintain healthy bones, but in line with what other experts recommend. The study makes no recommendation on dosages in humans, but it noted that there are few side effects to increased vitamin D intake, particularly in the D3 form. This study was posted online ahead of upcoming publication in the journal PNAS (Proceedings of the National Academy of Sciences). It can now be read in full at https://tinyurl.com/p48cvjn free of charge.
