News Briefs—November 2011
The Latest Research on Nutrition, Health & Anti-Aging From Around the World
BLUEBERRY POWDER CUTS CANCER TUMOUR SIZE, PROLIFERATION
A study has found that ingestion of whole blueberry powder results in smaller cancer tumours, and a reduced rate of metastases (spread of cancer to other locations). The diets of test mice were supplemented with whole blueberry powder in the amount of 5% of total food by weight. Cancer tumours were 75% smaller. Gene expression was also altered resulting in reduced inflammation, cancer and metastases. A second phase of the same study found that the blueberry supplement reduced liver cancer metastases by 70%, and lowered lymph node cancer metastases by 25%, compared to control mice. This just-released study will be published in the October 1, 2011 issue of the Journal of Nutrition.
DID YOU KNOW…? Treatment with vitamin C may slow or reverse the damaging effects of Alzheimer’s disease. In lab research on brain tissue, vitamin C dissolved toxic protein aggregates, the type of plaque that causes nerve cell death in the memory area of the brain. This study was reported in the August 5, 2011 issue of the Journal of Biological Chemistry.
CALCIUM / VITAMIN D REDUCE RISK OF CANCER, BUT NOT BONE FRACTURE
A large study has concluded that supplementation with calcium and vitamin D (among postmenopausal women who had not been taking these supplements before the study) resulted in a reduced risk of breast, invasive breast, and overall cancer. However, it had no effect on the risk of bone fractures or total mortality. (While extensive other research has shown a reduced risk of bone fracture with calcium and vitamin D supplementation, different studies often have conflicting results. A smaller study on bone density, not fracture risk, reported in the October 2011 issue of the journal Evidence Based Medicine, found vitamin D alone may improve bone density in children who are already D-deficient.)
The current study suggests that the anti-cancer benefits may outweigh possible bone benefits, whatever the level of bone benefit. Therefore, according to the research team, the main consideration in evaluating the potential benefits of calcium and vitamin D supplements should be the huge potential non-skeletal benefits and not merely the bone effects. In women not previously taking calcium-D supplements, these supplements produced a significant 14-20% reduction in the risk of these cancers. In women already taking calcium-D supplements, added supplementation produced no extra reduction in cancer risk. This study avoided the problem with past research on the effects of calcium-D supplements on cardiovascular risk, where there were conflicting results due to the fact that some participants already took supplements, while others did not. (Obviously, if many of the participants are already taking the supplementation, their further benefits from further supplementation are limited; those who have not been supplementing have the most to gain.)
This study was released August 31, 2011 but will not appear in print until a future issue of the American Journal of Clinical Nutrition. It is available now at https://bit.ly/q1xTZR with subscription or fee. (The vitamin D bone-density study mentioned above is also available online now at https://bit.ly/oeIVxi with subscription or fee.)
MICRONUTRIENT POWDERS REDUCE INFANT ANEMIA AND IRON DEFICIENCY
A new review of previous studies has found that adding micronutrient powders containing vitamins and minerals to the semi-solid foods of children aged between 6 months and two years reduces the risk of anemia and iron deficiency. (Micronutrient powders are single-dose packets containing vitamins and minerals in powder form meant to be sprinkled on semi-solid food immediately before eating; they are seen as home-use fortification. The World Health Organization reports that over two billion people worldwide have deficiencies of vitamins and minerals, especially of iron, vitamin A, and zinc.) In fact, the micronutrient powders reduced iron deficiency to the same extent as single iron supplements. The study did not, however, establish that the powdered supplements reduce the risk of deficiencies of other vitamins and minerals. This study released online September 7, 2011 by the Cochrane Database of Systematic Reviews.
CHONDROITIN SULFATE IMPROVES OSTEOARTHRITIS PAIN AND FUNCTION
Researchers have concluded that, compared to placebo, 800 mg of chondroitin sulfate daily reduces the pain associated with osteoarthritis of the hand, lessens morning stiffness, and improves functionality of the arthritic hand as well as non-steroidal anti-inflammatory drugs but without the long-term toxicities. (Osteoarthritis, or OA, is the most common form of arthritis and some studies have found that OA of the hand affects up to 20 – 30% of adults, and over 50% of those aged 60 and over. Chondroitin sulfate is a naturally occurring molecule and the main component of joint cartilage. It is often paired with glucosamine in supplements.) Symptoms of OA diminished for those taking chondroitin sulfate once daily for a period of 6 months, and the improvement was considered significant according to several pain and functionality scales. The supplement also increased grip strength. This study was released September 6, 2011 but will not be published until a future issue of the journal Arthritis & Rheumatism. It is accessible online now at https://bit.ly/qsYftZ with subscription or fee.
DID YOU KNOW…? No matter what popular dietary plan is pursued in terms of carbohydrates, fats, proteins, vitamins, minerals, grains, or sugars, it will become necessary to include foods typically found in the Mediterranean diet in order to meet those restrictions and still achieve nutrient adequacy. This study was reported August 7, 2011 by the American Journal of Clinical Nutrition.
ONE IN FIVE PEOPLE NOW HAS METABOLIC SYNDROME
A study has found that 19.1% of Canadians between six and 79 years of age have metabolic syndrome, indicating that almost one fifth of Canadians, and likely a greater proportion of Americans, have a high risk of diabetes and heart disease. (Metabolic syndrome refers to a constellation of conditions that raise the risk of diabetes and cardiovascular disease, and is defined as having at least three of five conditions: abdominal obesity, high triglycerides, low HDL or good cholesterol, high blood pressure or impaired glucose tolerance.) Age was the strongest predictor of the syndrome, which affects 39% of those in their 70s. Abdominal obesity was the most common characteristic. While this conclusion suggests a huge future increase in cases of diabetes and cardiovascular disease among Canadians, the news for Americans could be worse: Canadian rates of metabolic syndrome, which are similar to those in Australia, are considered to be lower than those in the U.S. The study was released September 12, 2011 by the Canadian Medical Association Journal and will appear in a future issue.
SOME SPICES AND FOODS BOOST ANTI-CANCER BENEFIT OF BROCCOLI
A study has found that pairing broccoli consumption with spices and foods that contain the enzyme myrosinase boosts the cancer-fighting power of each item, raises blood levels of a cancer-fighting broccoli compound, and ensures absorption in the upper digestive tract where the greatest benefit is derived. (Found in several spices and foods, myrosinase is an enzyme necessary for the formation of sulforaphane, which is a cancer-preventive compound contained in broccoli.) Sulforaphane is released during broccoli digestion, provided the vegetable is not overcooked, but this absorption involves the action of bacteria in the lower gut, which takes place at a slower rate than higher in the digestive tract, in the ileum. Researchers learned that eating broccoli with myrosinase-containing foods promotes faster, upper-digestive absorption and higher blood levels of sulforaphane. Items found to boost sulforaphane production and absorption included mustard, horseradish, wasabi, radishes, cabbage, arugula, and watercress. While it does not contain myrosinase, broccoli powder taken with broccoli also boosted sulforaphane. This study was released September 13, 2011 and will appear in a future issue of the British Journal of Nutrition. It is accessible online now at https://bit.ly/rgdS9C without cost.
WHITE-FLESH FRUITS AND VEGETABLES REDUCE THE RISK OF STROKE
A study has determined that every 25 gram increase in daily consumption of fruits and vegetables with white flesh, such as apples, lower the risk of stroke by 9%; for comparison, just one average apple contains about 120 grams. (Plant foods of different colours contain different types of phytonutrients, and all colours are linked to different health benefits. For this reason, dietary guidelines recommend eating produce from as many different colour groups as possible.) Highest consumption of white-flesh fruits and vegetables, and the phytonutrients they contain, was found to lower the risk of stroke by 59%, compared to lowest consumption. Other colours have other benefits, but only the white group was linked to lower stroke risk; three other tested colours did not have any effect on stroke risk: green, orange-yellow, and red-purple. Included in the anti-stroke white group were: apples, pears, bananas, cauliflower, chicory, and cucumber. Potatoes were not included, because they were classed as a starch. This 10-year study was released September 15, 2011 but will not appear in print until a future issue of the journal Stroke. However, it is available online now at https://bit.ly/odf3Er
EATING LOW-FAT YOGURT DURING PREGNANCY LINKED TO ASTHMA IN OFFSPRING
Researchers have uncovered a link between the consumption of low-fat yogurt during pregnancy and the development of child asthma and allergic rhinitis (hay fever), although the reason behind the correlation has not yet been determined. Scientists set out to determine whether asthma among children was associated with the consumption of the kind of fatty acids found in milk and dairy products by their mothers during pregnancy. They found no such connection with milk, but they did find that women who ate low-fat yogurt with fruit once a day were 1.6 times more likely to have children who developed asthma by the age of seven, and who were more likely to have allergic rhinitis. The reason for the link is not clear, but the scientists suggested that non-fat related nutrient compounds might play a role in increasing the risk. There is also the possibility that low-fat yogurt intake is common among those who share other dietary or lifestyle habits that increase the risk. This study will be presented in Amsterdam on September 25, 2011 at the annual congress of the European Respiratory Society.
DID YOU KNOW…? Despite common belief, potatoes are low in calories and contain phytonutrients and vitamins in amounts that rival broccoli, spinach, and Brussels sprouts. But these nutrients are destroyed in French fries and potato chips due to the high temperatures involved in frying.
MODERATE DRINKING HELPS PREVENT ATHEROSCLEROSIS
A study has found that, compared to no alcohol consumption, moderate alcohol drinking prevents weight gain, improves blood fat levels, and results in less development of atherosclerosis (hardening of the arteries), while weekend-binge alcohol consumption negatively affects these factors. In the mouse study, the same amount of alcohol given over a week to represent moderate consumption was given to another group over just two days of the week to represent binge drinking. Moderate drinking was defined as two drinks a day for a total of seven days of the week; weekend-binge drinking was deemed to be seven drinks a day for a total of two days of the week. This study confirmed the findings of large epidemiological (observational) studies on alcohol consumption and atherosclerosis disease in humans. But unlike epidemiological studies, it also allowed scientists to control potentially confounding factors such as smoking, lifestyle habits, and differing dietary habits. The team did not suggest a possible mechanism by which drinking might affect artery disease. This study will be published in a future issue of the journal Atherosclerosis but was released early and is available online now at https://bit.ly/rlvViW with subscription or access fee.
ZINC PROVEN CRITICAL TO BRAIN CELL COMMUNICATION
Researchers have largely confirmed that zinc plays a key role in the communication between brain cells, and may regulate neuron activity in the hippocampus where learning and memory processes occur and where disrupted communication contributes to epilepsy. (Zinc tablets are currently sold over the counter for certain brain disorders such as clinical depression. It has long been known that high zinc concentrations are found in the vesicles – specialized compartments of nerve cells responsible for packaging the transmitters that allow communication between brain neurons. But until now, it has been unclear whether this means zinc actually plays a role in the nerve cell communication itself.) Eliminating zinc from vesicles prevented enhanced neuron communication. This suggests zinc is crucial to brain cell communication. Areas of highest zinc concentration were those critical for memory formation. The research team also found greater epileptic severity among epileptic animals with an excessive enhancement of communication by zinc-containing cells; this suggests the overall balance of zinc may be important. This study was released September 21, 2011 but will not be published until a future issue of the journal, Neuron. It is available online now at https://bit.ly/oFFyyN with subscription or fee.
MAITAKE AND CANCER
Human breast cancer cells are more likely to commit cellular suicide (apoptosis) in the presence of substantial doses of D-fraction, a bioactive found in maitake mushrooms. The greater the dose, the greater the effect, reported the June 2011 issue of the Journal of Medicinal Food.
DID YOU KNOW…? Although a July, 2011 study in The Lancet shocked even experts with its estimate of 347 million diabetics worldwide (more than doubling the 153 million total in 1980), the International Diabetes Federation presented evidence Sept. 13, 2011 that the real total is 366 million.
PAIN THRESHOLD INCREASES AFTER UNRESTRAINED LAUGHTER
Researchers have found that about 15 minutes of repeated but unforced laughter, of the type that creases the eyes, naturally raises the threshold of pain by 10% for several hours afterward by triggering the release of pain-alleviating endorphins. (Laughter that is unforced has previously been hypothesized to generate opium-like endorphins in response to the temporary exhaustion caused by the muscle exertion of exhaling without drawing in air. Endorphins are complex chemicals that help transmit messages between neurons; they also dull signals of physical pain and psychological stress. Endorphins are also released by running, rowing, and other forms of physical exercise; exercise is also a part of explosive laughter.) The laughter that proved successful in increasing pain tolerance was the relaxed kind of unforced laughter instead of a chuckle or polite titter. The scientists also found that this pain-dulling kind of laughter is more likely to occur when you are with friends rather than alone. This study was released September 14, 2011, but will not be published until a future issue of the biological sciences journal, Proceedings of the Royal Society B.
WALNUTS BOOST COGNITIVE FUNCTION
Researchers have discovered that walnuts, which are rich in antioxidants, increase the ability to perform inferential reasoning, especially the ability to distinguish true from false, although walnuts do not improve memory or non-verbal reasoning abilities. (Inferential reasoning is the ability to do critical thinking to deduce new information based on the context and experience.) An intensive 8-week supplementation of the diet with walnuts increased critical thinking significantly. One group ate banana bread containing ground walnuts, while the other ate the same bread without any nuts. It should be noted that the study was funded by the California Walnut Commission, which was not allowed any input on the study design or findings. This just-released study will be published in a future issue of the British Journal of Nutrition. It is available online now at https://bit.ly/nkrn2G without fee.
MIDSECTION FAT LINKED TO ASTHMA RISK
Researchers have found that people who are not otherwise obese but who suffer from central obesity, better known as belly fat, a condition often reflected in the body mass index (BMI), have a 1.44 times greater risk of developing asthma; and those who are obese both around the middle and elsewhere have a 1.81 times greater risk of asthma. Excess abdominal fat has been linked previously to increased health risks such as diabetes and heart disease, but researchers have largely ignored any potential link to lung disease. The new study followed 23,245 subjects for 11 years, and monitored waist circumference and BMI to determine individual levels of overall obesity compared to central obesity. The team concluded that overall obesity and central obesity each constitute a higher risk of asthma, but together the risk is greater. Central obesity is linked to metabolic syndrome and insulin resistance, but it is unclear how belly fat affects asthma risk. (Another study released the same day found moderate alcohol intake reduces asthma risk.) This study was presented in Amsterdam on September 25, 2011 at the annual congress of the European Respiratory Society.
ACETYL-L-CARNITINE MAY TREAT OR REVERSE SPINAL CORD INJURY
A study has found that the supplement acetyl-L-carnitine (ALC) can protect neuron cells and assist overwhelmed mitochondria, preventing them from shutting down, which in turn can halt the normal death of neuron cells following a spinal cord injury. (ALC is a derivative of essential amino acids that can generate metabolic energy. Mitochondria are the energy-generating components inside cells. During spinal cord injury, local mitochondria are overwhelmed by chemical stresses and lose their normal ability to produce energy, leading to cell death, which causes paralysis.) Administration of ALC shortly after spinal injury was found to supply alternative energy for cells, bypassing the reduced supply from mitochondria and protecting neuron cells from death. Protecting cells from death allowed treated subjects to fully recover from paralysis and walk normally within a month. This research was conducted on mice, but there could be huge implications for future treatment, and even reversal, of recent spinal cord paralysis in humans. (ALC can be given orally and high doses are well tolerated.) Further details have not been released, but this study will be presented in Washington, DC, on Sunday, November 13, 2011, at a meeting of the Society for Neuroscience.
LOW LEVELS OF VITAMIN B12 CAN LEAD TO BRAIN SHRINKAGE
A study has found that, at least in people over age 65, having high levels of four out of five markers in the blood that indicate a vitamin B12 deficiency can lead to a smaller brain volume and lower cognitive test scores about 4.6 years down the road. (Directly measuring vitamin B12 levels in the blood of older persons is not a reliable indicator of a deficiency; as a result, scientists measure other factors in the blood such as homocysteine, which more accurately indicate whether the body is experiencing a B12 deficiency.) The team reported that further research will be needed to determine whether supplementation would prevent the brain damage. However, the study does conclude that vitamin B12 deficiency can cause brain atrophy and cognitive impairment. The study was published in the September 27, 2011 issue of the journal Neurology. It is available online at https://bit.ly/nYrYdR with subscription or study access fee.
DID YOU KNOW…? A third of runners incorrectly believe they need sports drinks to prevent low sodium when racing. However, sports drinks are actually the main cause of low sodium, reports a study published in the June 2011 issue of the British Journal of Sports Medicine.
