News Briefs – June 2013Michael Downey June 1, 2013
Did You Know…?
A green tea compound known as epigallocatechin gallate, or EGCG, has been found to help prevent the mis-folding of proteins in the brain that is associated with Alzheimer’s disease and other neurodegenerative disorders.
Naturopathic Treatment Reduces Cardiovascular Risk Factors
Researchers have found that counseling and treatment with naturopathic care reduced the prevalence of metabolic syndrome, which is a risk factor for heart disease, by 17% within one year. The study was a randomized, controlled trial involving 246 members of the Canadian Union of Postal Workers at Toronto, Vancouver, and Edmonton. Naturopathic lifestyle counseling and naturopathic care was given to some participants seven times over the course of one year, while the control group received normal but enhanced care.
The naturopath-counseled subjects significantly reduced key risk factors for cardiovascular disease. Naturopathic doctors provided diet and lifestyle advice for patients to lose between 5 and 9 pounds (between 2.3 and 4.2 kg) through a combination of caloric restriction and regular physical exercise, and dispensed natural health products such as omega-3 fatty acids, soluble fibre, coenzyme Q10 and other therapies. Prevalence of metabolic syndrome was reduced by 17 percent; risk for cardiovascular disease on the Framingham score decreased by 3%. In an accompanying editorial, the deputy editor cautioned against drawing conclusions about any supplements that were used, but wrote that, “some aspects of cardiovascular prevention could feasibly and effectively be delegated to naturopaths.” This study was released April 29, 2013 on the website of the Canadian Medical Assn. Journal. The full study can now be downloaded from https://tinyurl.com/cg3f28n without charge.
High-Fat Meals Boost Blood Sugar in Type 1 Diabetes
Researchers have found that, in patients with Type 1 diabetes, dietary fat impairs insulin sensitivity and increases blood sugar production in patients with Type 1 diabetes. (Although most research has focused on Type 2 diabetes, some studies of Type 1 diabetics have shown that higher-fat pizza meals cause hyperglycemia, or high blood sugar, hours after being consumed. This study set out to confirm this effect and determine the underlying factors that caused this dietary fat-related surge in blood glucose levels.)
All breakfasts and lunches given to patients in this study featured identical low-fat content. The two different types of dinner had identical carbohydrate and protein content, but one contained six times the fat of the other. Study results showed that, while the two breakfast meals required similar insulin doses, participants required substantially more insulin after eating the high-fat dinner than the low-fat dinner. And despite the increased insulin, participants still had greater hyperglycemia five to ten hours after the high-fat dinner.
These findings highlight the limitations of basing recommendations for Type 1 diabetics solely on carbohydrate intake; it is important to consider fat as well as carbohydrates in dosing and in nutritional recommendations.
This study appeared in the April 2013 edition of Diabetes Care. The full text is now available online at https://tinyurl.com/d3aqje2 free of charge.
Amount Of Dietary Trans Fats Linked To Higher Mortality Rate
New research has found that higher trans fat intake is associated with an increased risk of all-cause mortality. (Trans fat is the common name for unsaturated fats with a specific molecular structure; they can be monounsaturated or polyunsaturated but are never saturated. Although they do exist in nature, they often occur during the processing of polyunsaturated fatty acids in food production. A high intake decreases HDL or good cholesterol, and is associated with increased LDL or bad cholesterol, inflammation, diabetes, cancer, and mortality from cardiovascular disease. However, the relation between trans fat intake and all-cause mortality had not been established prior to this new study.)
Over 18,000 subjects were followed for 7 years and each was categorized according to his intake of dietary trans fat. Even after adjusting for confounding factors, those in the highest quintile of trans fat consumption were found to have a 24% greater risk of death from all causes combined compared to subjects in the lowest quintile.
This study was released online April 3, 2013 by the American Journal of Clinical Nutrition. It will be published in a future issue, but it is available now at https://tinyurl.com/c59hlwn with journal subscription or access fee payment.
(Editor’s note: According to the U.S. Centers for Disease Control, the most common food sources of trans fats include “fried items, savory snacks (like microwave popcorn), frozen pizzas, cake, cookies, pie, margarines and spreads, ready-to-use frosting, and coffee creamers.”)
Walking Lowers Risk Of Heart Disease And Diabetes As Much As Running
Scientists have found that the risk of high blood pressure, high cholesterol, diabetes, and possibly cardiovascular disease is reduced as much by moderate exercise – such as brisk walking – as by vigorous exercise such as running. In a six-year study of over 33,000 runners and over 15,000 brisk walkers, the exercise expenditure was measured in terms of distance rather than time. Study participants were 18 to 80 years old, clustered in their 40s and 50s. The greater the amount of distance covered, the greater the health benefits. The results indicated that running significantly reduced the risk for developing high blood pressure by 4.2%, while walking reduced this risk by 7.2%. Also, running reduced the risk of developing high cholesterol by 4.3%, while walking reduced this risk by 7%. The risk of developing diabetes was reduced by 12.1% by running, while the risk of diabetes was reduced by 12.3% by walking. There was a 4.5% decrease in the risk of developing coronary heart disease for runners, while brisk walkers lowered their coronary heart disease risk by 9.3%.
This study was released early, ahead of later publication in the journal Arteriosclerosis, Thrombosis and Vascular Biology. It is now available online at https://tinyurl.com/cwzyq3r with access fee or subscription.
Female Smokers Have Twice The Colon Cancer Risk Of Male Smokers
New research has found that smoking increases the risk of colon cancer in both males and females, but the risk is significantly higher among women smokers. The experts also found that the more and longer a woman smoked, the greater her risk for colon cancer. Also, women who smoke less than men still get more colon cancer. (Globally, during the last 50 years, the number of new colon cancer cases per year has exploded for both men and women. A previous report showed that not smoking, exercising more, and cutting down on red meat and alcohol can reduce the risk of colon cancer.)
This research is considered very reliable because of the high number of participating subjects: 600,000 men and women. The scientific team examined various factors, such as exercise level, seeking associations with colon cancer, but only smoking showed a risk link to this cancer. Women smokers had a 19% elevated risk compared with those who never smoked, while men smokers had an 8% higher risk compared to those who never smoked. The results also showed that women who began smoking when they were 16 years or younger, and women who had smoked for 40 years or longer, had a considerably elevated likelihood of developing this cancer; the risk of colon cancer for these women is a shocking 50% higher, more than double the risk for other women smokers.
This study was released online first, ahead of publication in a later edition of the journal Cancer Epidemiology, Biomarkers and Prevention. The full study can be read at https://tinyurl.com/cclaerv on the journal website.
DHA Boosts Memory In Young Women, And Memory Speed In Young Men
A new study suggests that memory function in young people whose habitual diets are low in the omega-3 acid known as docosahexaenoic acid, or DHA, improves with supplementation of 1,160 mg of DHA per day and that the effect is different in men and women. (DHA is one of the omega-3 fatty acids found in cold water fatty fish, such as salmon. These memory-related abilities are the building blocks of more complex cognitive brain functions and everyday cognition-related behavior.) Previous research only studied DHA effect on elderly people. But this study investigated DHA effect on the memory abilities of DHA-deficient subjects aged 18 to 45, a group the scientific team defined as young men and women. (We were thrilled to learn that 45 is considered young.)
After six months, all subjects were re-tested on cognitive abilities using a warfare-based computer game. (This could skew results more towards men). Memory and reaction time improved compared to placebo. Women improved more in episodic memory, and men improved more in episodic reaction time. (Episodic memory includes the degree of recall of autobiographical times, places and events; episodic reaction time includes speed of this recall.) This study appeared in the May 2013 issue of the American Journal of Clinical Nutrition.
Most Food Poisoning Deaths Occur Among The Elderly, Says U.S. Government Report
A new government study reports that there were about 20,000 cases of food-borne infection in the U.S. in 2012, with the highest incidence among young children and the greatest proportion of hospitalizations and deaths among the elderly. (It is frequently suggested that most cases of food poisoning go unreported, because victims assume they have picked up a 24-hour flu, although in fact, there is no such virus. These findings might be seen as highlighting the need to identify and address food safety gaps, because all of these cases could be termed avoidable.)
Salmonella, Campylobacter, Shigella, and Crypto-sporidium were the most common pathogens in 2012. The researchers found that there were 19,531 infections, 4,563 hospitalizations, and 68 deaths associated with food-borne diseases. For most infections, the incidence was highest for children under 5 years old, while people aged 65 and older had the highest percentages of hospitalizations and deaths.
This research was published in the April 19, 2013 issue of the Morbidity and Mortality Weekly Report, which is produced by the US Centers for Disease Control and Prevention. The full text of this report can be read at https://tinyurl.com/cd7oxpu free of charge.
Scientists Identify Artery-Clogging Compound In Meat
Researchers have found that carnitine, which is a compound abundant in red meat and added as a supplement to energy drinks, promotes atherosclerosis, or the hardening or clogging of the arteries. They also found that carnitine causes this damage in conjunction with human digestive-tract bacteria that metabolize the compound, turning it into trimethylamine-N-oxide (TMAO), a metabolite previously linked to the promotion of atherosclerosis in humans. Further, the research found that a diet high in carnitine promotes the growth of the very bacteria that metabolize carnitine, compounding the problem by producing even more of the artery-clogging TMAO.
Remarkably, vegans and vegetarians, even after consuming a large amount of carnitine, did not produce significant levels of the TMAO metabolite, whereas omnivores consuming the same amount of carnitine did. (Apparently, the bacteria living in our digestive tracts are dictated by long-term dietary patterns, not by occasional spikes in carnitine intake; meat-eaters take in carnitine regularly while vegetarians do so only occasionally.)
The study showed that TMAO alters cholesterol metabolism at multiple levels, explaining how it promotes atherosclerosis. Increased carnitine levels in patients predicted increased risks for cardiovascular disease and major cardiac events like heart attack, stroke, and death, but only in subjects with concurrently high TMAO levels (produced by certain bacteria that feed on carnitine). Specific gut microbe types in subjects associated with plasma TMAO levels and TMAO levels themselves were significantly lower among vegans and vegetarians than omnivores.
These findings may explain the artery risks of meat consumption better than saturated fat and cholesterol; and they may explain the cardiovascular health benefits of meat-free diets. While carnitine is naturally occurring in red meats, including beef, venison, lamb, mutton, duck, and pork, it is also a dietary supplement available in pill form and a common ingredient in energy drinks. Carnitine is not an essential nutrient; our body naturally produces all we need. This study was released April 7, 2013 by Nature Medicine. It will appear in a future issue of this journal, but can be accessed online now at https://tinyurl.com/dxd29xz with subscription or fee.
Vitamin E May Help Prevent Obesity-Related Liver Disease
A new study has found that a deficiency of vitamin E in obese mice is associated with development of a liver disease known as nonalcoholic steatohepatitis or NASH. (NASH is characterized by the accumulation in the liver of fat, oxidative stress, and inflammation. It is linked to two major epidemics: obesity and diabetes. It is not caused by alcohol consumption.)
An essential antioxidant, vitamin E had been shown in other recent studies to alleviate some symptoms of NASH in human patients, suggesting that there is a link between inadequate vitamin E levels and liver disease. To test this hypothesis, the team studied mice that are engineered to lack a protein that regulates and maintains the levels of vitamin E in the body. As expected, they observed increased oxidative stress, fat deposition, and other signs of liver injury in the mice. Importantly, supplementation with vitamin E averted the majority of NASH-related symptoms in these animals, confirming the relationship between vitamin E deficiency and liver disease. Although the recommended dietary allowance for vitamin E for adults is only 15 mg or 22.4 IU a day, the team pointed out that a majority of adults do not consume this amount. Certain vegetable oils, as well as nuts and seeds, leafy greens and fortified cereals commonly contain vitamin E.
This report was delivered April 24, 2013 in Boston at the annual meeting of the American Society for Biochemistry and Molecular Biology, held in conjunction with the Experimental Biology 2013 meeting.
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Michael Downey is a former columnist with Vitality Magazine.