News Briefs – September 2010
ARTIFICIALLY SWEETENED DRINKS RAISE RISK OF PRE-TERM BIRTHS
Sugar-sweetened drinks have been linked to health problems such as weight gain; as a result, artificially sweetened soft drinks have often been promoted as an alternative. However, the effect of these drinks on pregnant women has seldom been examined. A new study has found that daily consumption of artificially sweetened soft drinks appears to increase the risk of women delivering babies pre-term. The effect was observed whether the artificially sweetened soft drink was carbonated or non-carbonated. The study analyzed data from 59,334 formerly pregnant women and found that the earliest and moderately early pre-term deliveries were more strongly associated with daily consumption of artificially sweetened drinks than late-term pre-term deliveries. The association – while not necessarily one of cause-and-effect – is worrisome and demands further study, wrote the researchers in an abstract, or summary, released June 30 by the American Journal of Clinical Nutrition.
The full-text version is available to read online, with a subscription or the payment of a fee, at: https://bit.ly/aG3zR3.
VIRGIN OLIVE OIL CHANGES HOW GENES FUNCTION
It is known that a Mediterranean diet lowers cardiovascular risk. But finally, a study has determined how the key ingredient in this diet, virgin olive oil, works: it changes the way our genes function – those genes associated with atherosclerosis, or hardening of the arteries. Three groups of healthy volunteers were tested: the first group consumed a Mediterranean diet rich in virgin olive oil high in polyphenols; the second group consumed a diet rich in ordinary olive oil, low in polyphenols; and the third group followed its normal diet. After three months, only the first group exhibited what is known as a down-regulation, or reduced activity, of specific genes – genes associated with atherosclerosis. But that wasn’t all: the virgin olive oil group also showed a benefit against inflammation, insulin resistance, cancer, and tumours. Virgin olive oil and the Mediterranean diet affect our bodies in far more ways than previously believed, suggested the researchers. The study appears in the July 1, 2010 issue of the journal FASEB.
KEY INGREDIENT IN HONEY KILLS ANTIBIOTIC-RESISTANT BACTERIA
A study has identified why honey seems to have antibacterial qualities and, in fact, how it may be a potent weapon against antibiotic-resistant bacteria. Researchers developed a way to identify the individual anti-bacterial contribution of the various known antibacterial ingredients found in honey. One protein, known as defensin-1, is part of the bees’ immune system and is added to honey by the bees.
After analysis, the team concluded that the bulk of honey’s bacteria-fighting potency derives from defensin-1 and that, in the future, it may serve as a treatment for burns and skin infections. Also, this information may lead to the breeding of bees that produce honey with even higher levels of this protein. This would make honey a potent remedy and take the sting out of many bacterial infections. The study appears in the July, 2010 issue of the journal FASEB.
ADDED FRUCTOSE LINKED TO HYPERTENSION
Those who consume a diet high in drinks sweetened with sugar in the form of fructose may be at a higher risk of developing hypertension, or high blood pressure, according to a new study. A dramatic increase in the consumption of the simple sugar fructose, used to sweeten a wide variety of processed foods, mirrors the dramatic rise in cases of hypertension, the most common chronic condition in developed countries and a major risk factor for heart and kidney diseases.
Researchers found that people consuming a diet of 74 grams or more per day of fructose – corresponding to two and a half fructose-sweetened soft drinks daily – had a 26, 30, and 77% higher risk for blood pressure levels of 135/85, 140/90, and 160/100 mmHg, respectively. (A normal blood pressure reading is below 120/80 mmHg.) This study will appear in a future issue of the Journal of the American Society of Nephrology: full-text version available at bit.ly/abkC16
DEPRESSION LINKED TO VITAMIN D DEFICIENCY
A study of 2,070 people in the UK over age 65 has concluded that, among older adults living in northern latitudes, those with a vitamin D deficiency have a significantly greater risk of showing the common symptoms of clinical depression. To determine this link, researchers analyzed data in a way that would rule out other potential factors such as age, gender, social class, and physical health status. The correlation was also found to be independent of the specific season of the year during which subjects were examined. Deficiency of vitamin D was defined as blood levels of less than 10 ng/mL, or 10 nanograms per milliliter. This is in keeping with, and lends credibility to, recent and past studies with similar findings. This latest research was posted online July 1, 2010, although it won’t be published in print until a future issue of Psychosomatic Medicine.
HIGH LEVELS OF VITAMIN E REDUCE RISK OF ALZHEIMER’S
A study has found that, for people aged 80 and above, high levels of the various forms of vitamin E in the blood lower the risk of getting Alzheimer’s disease. Most prior studies of Alzheimer’s and vitamin E focused strictly on one form of this vitamin, [d-alpha] tocopherol. But researchers found that all eight natural forms of vitamin E [mixed tocopherols and tocotrienols], likely working together, afford some protection against this memory-robbing disease. The third of subjects found to have the highest blood levels of all eight vitamin E forms showed a 45 to 54% reduced rate of Alzheimer’s disease compared to those with the lowest blood levels. There had been some suggestion that too much of one form of vitamin E might increase mortality but the new study is a strong argument that “the balanced presence of different vitamin E forms can have an important neuroprotective effect.” Most of those afflicted with Alzheimer’s are over age 70. If you have questions about whether you could benefit from vitamin E supplements, speak with your health practitioner. The study was published in the July, 2010 issue of the Journal of Alzheimer’s Disease and details are available at https://bit.ly/cF5vZg but only to subscribers or those willing to pay a temporary access fee.
DEPRESSION DOUBLES RISK OF DEMENTIA
A study has found that having depression may nearly double your risk of developing dementia later in life. For 17 years, the study followed 949 people with an average age of 79. Those who were depressed at the start of the study showed a 70 percent greater risk of developing dementia. The results were the same after making allowance for age, gender and education. The study did not establish that depression causes dementia but a number of depression-related factors may affect the risk of dementia. “Inflammation of brain tissue that occurs when a person is depressed might contribute to dementia,” wrote the researchers. “Certain proteins found in the brain that increase with depression may also increase the risk of developing dementia. In addition, several lifestyle factors related to long-term depression, such as diet and the amount of exercise and social time a person engages in, could also affect whether they develop dementia.” Past studies have been inconclusive but this study appears to set the record straight. The research was published in the July 6, 2010 issue of Neurology.
DISRUPTED CLOCK GENES CAUSE CARDIOVASCULAR DISEASE
A study has found that numerous “clocks,” which control genes all over the body, contribute to high blood pressure and cardiovascular diseases when they are out of sync with the body’s main clock. Heart attacks, high blood pressure and other vascular functions have been known to have daily cycles in tune with the body’s central clock, which is located in the hypothalamus, a part of the brain. But peripheral clocks in each tissue or cell also control body events in every part of the body. This study found that when these mini-clocks are out of sync with the main body clock, various disorders can be triggered such as high blood pressure, cardiovascular diseases, hemostasis, and endothelial dysfunction. This research on genetically engineered mice now suggests that locating these clock-controlled genes (CCG) within each organ and learning how to adjust their phases could result in a clock-controlled approach to preventing cardiovascular diseases. The study was published online July 7, 2010 by the journal Hypertension Research.
FISH OIL MAY REDUCE BREAST CANCER RISK
A study of 35,016 postmenopausal women with no history of breast cancer has found that fish oil supplements may reduce the risk of this disease by 32%. The study looked only at “specialty” supplements taken by each subject, those that did not fall into the category of vitamins or minerals. The risk of invasive ductal breast cancer – the most common type of the disease – was shown to be reduced in those taking fish oil supplements, which contain high levels of the omega-3 fatty acids, EPA and DHA. None of the other “specialty” supplements, commonly taken for menopausal symptoms, showed any association to breast cancer. Previous studies of dietary omega-3 oils or fish provided conflicting results. This study’s researchers speculate that fish oil supplements may contain much higher amounts of omega-3 fatty acids than are normally consumed in even an omega-3-rich diet and this could explain the difference in findings between supplements and diet. A brief summary was released July 8, 2010 by the journal, Cancer Epidemiology, Biomarkers & Prevention.
ALZHEIMER’S, PARKINSON’S, CJD: ALL CAUSED BY PAST SURGERY?
A jarring statistical study concludes that, with few exceptions, those who become afflicted with sporadic Creutzfeldt-Jakob disease (CJD) do so 20 years after some type of surgery. (Caused by an infectious protein called a prion, Creutzfeldt-Jakob disease or CJD is the brain-wasting and always fatal disease that slowly causes holes in the brain, making it sponge-like. It is the human variant of mad cow disease, and scrapie in sheep, and is also called Transmissible Spongiform Encephalopathy or TSE. (Heredity can be a cause but most cases are called sporadic, meaning their cause is unknown.) The reliability of the data prompted researchers to conclude there is a cause-and-effect relationship between CJD and surgery.
Without ruling out blood transfusions as the route, the team suggested that prions may enter the body through the central or peripheral nervous system, conceivably from sanitized but re-used equipment. (Unlike germs, prions are not alive and have no DNA, making them impossible to destroy by traditional methods such as heat or radiation.) But the nervous system route has greater implications: if CJD is externally caused by surgery, then other neurodegenerative diseases such as Alzheimer’s and Parkinson’s could also be transmitted through surgery and lie dormant for decades before striking.
This study will be published in a future issue of the Journal of Neurology, Neurosurgery & Psychiatry but is available online now, without charge or journal subscription, at: https://bit.ly/bxamv6.
SIMPLE TOOL PREDICTS DIABETES 2 RISK
A study has developed a simple measure to predict an individual’s risk of diabetes type 2. Ordinarily, various factors give a general risk indication: for example, having a family member with diabetes, or having a large waist measurement. But researchers have found that using a “nomogram” that combines two readings is much more accurate, in addition to being quicker, easier and cheaper. The two readings are the systolic blood pressure reading (the upper blood pressure number) and the waist-to-hip ratio, or WHR. The higher the score on each, the higher is the risk. (A nomogram is a tool that shows three parallel lines on a sheet of paper with, in this case, the line on the left representing the systolic reading, the line on the right representing the WHR and the middle line representing the resultant risk. A line is drawn from the systolic reading to the WHR and where it intersects the middle line represents the risk of diabetes.)
Details of this just-released study won’t appear until a future issue of the journal Diabetologia, although they are available in advance only with payment of a fee, at: https://bit.ly/asW2q9.
OBSTRUCTIVE SLEEP APNEA INCREASES RISK OF HEART FAILURE
A study has found that men aged 40 to 70 who suffer from obstructive sleep apnea (OSA) have a higher risk of heart failure and coronary heart disease. This link was not found in women or in men over 70. (Obstructive sleep apnea is a sleep disorder in which sleeping patients repeatedly stop breathing for at least 10 seconds. Heart failure occurs when the heart is weakened to the point that it cannot supply enough blood for the body’s need. Coronary heart disease is the inability of the blood vessels of the heart to supply sufficient blood to heart muscles.) A total of 1,927 men and 2,495 women free of heart problems were tested. Men – but not women – with significant OSA were found to have a 68% greater risk of coronary heart disease and were 58% more likely to develop heart failure. If you suspect you might have OSA, talk to your health practitioner. A brief summary of this study was released July 12, 2010 and will appear in a future issue of the journal, Circulation.
LOW VITAMIN D STATUS MAY RAISE PARKINSON’S RISK
A study of 3,000 people has found that those with the lowest blood levels of vitamin D appeared to be three times as likely to develop Parkinson’s disease later in life – in this study, up to 30 years later – compared to those highest in vitamin D levels. (Parkinson’s affects several brain areas and causes tremors and slow movements.) Vitamin D is called the sunshine vitamin because the skin can produce substantial amounts when in the presence of sunlight. It is also found in oily fish, milk, cereals and supplement pills. For years, scientists have known that vitamin D assists calcium uptake and bone formation but recent evidence suggests it plays a role in regulating the immune system and developing the nervous system. A level of 30 nanograms per milliliter of blood appears optimal for bone health. But the researchers suggested further research to determine the optimal blood level of vitamin D for brain and nerve health, as well as to determine the level of toxicity, neither of which is known. This study was published in the July 2010 issue of the journal, Archives of Neurology.
CASHEW SEED EXTRACT COMBATS DIABETES
A study has found that cashew seed extract is an effective anti-diabetic and may be useful as a nutraceutical (a product that provides health and medical benefits) to combat diabetes. Researchers concluded that the cashew seed extract significantly stimulated absorption of blood sugar into muscle cells. (Diabetic persons have high blood sugar because their body does not respond well to insulin or does not produce enough of the hormone. Insulin fuels the absorption of blood sugar into the body’s muscles.) Cashew products – leaves, bark, seeds and apples from cashew trees – have traditionally been alleged to be beneficial to diabetics. The new study found that, of these products, only cashew seed extract lowered blood sugar. This confirms the traditional use for diabetes and points to possible future oral remedies. A summary of this study has been released early online, and will be published in a future issue of Molecular Nutrition & Food Research.
ALCOHOL BOOSTS STROKE RISK FOR ONE HOUR AFTER CONSUMPTION
Previous research has shown that regular heavy drinking of alcohol increases the risk of ischemic stroke; research also has shown that regular light to moderate drinking can decrease the risk. But what effect on stroke risk does random or irregular alcohol drinking have? Does a single drink produce an immediately higher risk? And do different types of alcoholic beverages pose different ischemic stroke risks? (Ischemic stroke is a stroke characterized by reduced blood supply to the heart.) Scientists interviewed 390 stroke victims and compared their regular alcohol consumption with their consumption just prior to the stroke. It was found that the risk of stroke more than doubles for the hour immediately following an alcoholic drink. Also, the risk does not vary with the type of drink and is independent of other risk factors (such as smoking). A brief abstract, or summary, of this study was released July 15, 2010 and will be published in a future issue of the journal, Stroke.
In the meantime, the full-text version can be read online, with a subscription to the journal or payment of an access fee, at: https://bit.ly/bMXeSf.
MECHANISM FOR CALORIE RESTRICTION’S LONGEVITY EFFECT DISCOVERED
A study has provided insight into how a calorie restricted diet extends lifespan and prevents age-related diseases. (Scientists have long known that calorie restricted diets or CR, and very low calorie diets or VLCD, have this longevity effect in animals, and presumably in humans, but the mechanism is unclear.)
This study on mice looked for senescent cells – cells that have reached the point where they can no longer reproduce – to determine whether a calorie restricted diet had any effect on this process, believed to be the main cause of aging. They found a reduced accumulation of senescent cells in the liver and intestines, organs known to accumulate large numbers of these cells with age.
Also, the telomeres – protective tips on the ends of chromosomes that prevent cell replication errors and disease until they shorten with age – were better maintained in the calorie restricted mice. Because the effect occurred after a short period of restriction, the researchers suggested that the longevity benefit might occur even when the CR diet is adopted later in life rather than for an entire lifetime.
This study was presented at the conference of the British Society for Research on Ageing (BSRA) in Newcastle, UK, on July 16, 2010.
FRUCTOSE PROMOTES CANCER GROWTH
Carbohydrate metabolism is essential for cancer growth and increased refined carbohydrate consumption is known to affect cancer survival. A new study suggests that – contrary to conventional wisdom – refined fructose, a sugar and carbohydrate, is metabolized differently than the sugar known as glucose; and that, unlike glucose, fructose causes cancer cells to multiply.
Traditionally, sugars were considered to be so similar that they must be metabolized by the body in much the same way and little attention has been given to sugars other than glucose. But the study found that fructose – consumption of which has increased dramatically in recent decades – is delivered to cells using different transporters than glucose. Further, fructose is readily metabolized by cancer cells to produce certain compounds that result in the proliferation of the cancer.
The study drew a direct link between fructose and increased pancreatic cancer growth. The researchers concluded that cancer patients should reduce their intake of refined fructose in order to disrupt cancer growth. The study was just released by Cancer Research, and will be published in a future issue of the journal.
It is available online to subscribers to the journal, or those willing to pay the $35 article access fee, at: https://bit.ly/9XxUOC.
BLUEBERRIES REDUCE CARDIOVASCULAR RISK
A small study has found that an amount of blueberry consumption that is achievable by diet alone reduces key cardiovascular disease risk factors in obese men and women with metabolic syndrome. (Metabolic syndrome is a combination of disorders that increase the risk of developing cardiovascular disease and diabetes.) Every day for 8 weeks, 48 participants consumed a beverage comprised of 960 mL of water, 50 gm of freeze-dried blueberries and about 350 gm of fresh blueberries. Researchers found that, compared with the control group, the blueberry group showed lower systolic and diastolic readings – the upper and lower numbers in a blood pressure reading. They also found lower blood levels of LDL, or “bad cholesterol” in the blueberry group. The blood sugar levels were not affected.
The study concluded that “blueberries may improve selected features of metabolic syndrome and related cardiovascular risk factors,” at doses that can be achieved through food consumption alone.
This study was released July 2 by the American Journal of Clinical Nutrition.
