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April 2006 Vol. 11 No. 4

 To accuse others for ones misfortunes is a sign of want of education.To accuse oneself shows that ones education has begun.  To accuse neither oneself nor others shows ones education is complete.
-Epictetus

Table of Contents:

Coffee’s Risk to Your Heart Depends Upon Your Metabolism
Too Much or Too Little Sleep Raises Your Diabetes Risk
Beat Prostate Cancer by Getting Your Omega-3s
Cholesterol-Lowering Foods Most Effective When Combined
Mental Stress Effects On Heart More Common Than Previously Known
NutraSweet Shown to Cause Cancer
Glycemic Index Deception Finally Understood
Coconut Oil

Coffee’s Risk to Your Heart Depends Upon Your Metabolism  

People who have a genetic trait that makes them slow caffeine metabolizers have a higher risk of heart attack associated with drinking coffee.

Metabolized Rapidly or Slowly

A study of more than 4,000 people showed that about half had a genetic factor that makes caffeine stay longer in their bodies. The other half metabolized caffeine rapidly, and experienced no increase in heart attack risk from coffee drinking.

Four Times as Likely

Slow-metabolizers who drank two or more cups of coffee daily were 36 percent more likely to have a heart attack than those who drank little or none. The risks were even higher for slow-metabolizing coffee-drinkers under 50, who were as much as four times more likely to have a heart attack than their peers.

May Explain Earlier Contradictions

These findings might explain why previous studies on the effects of caffeine have had mixed results. Some previous research linked coffee-drinking to a higher risk of heart disease, while other studies have indicated the opposite.

JAMA 2006;295:1135-1141
Yahoo News March 7, 2006
Science Daily March 8, 2006

Too Much or Too Little Sleep Raises Your Diabetes Risk 

Both too little and too much sleep could increase your risk of type 2 diabetes. A 15-year study of more than 1,000 men found that those getting less than six or more than eight hours of sleep a night had a significantly increased diabetes risk.  The risk was roughly twice as high for those sleeping relatively short periods, and more than three times as high for those who slept for long periods. Those who slept for seven to eight hours a night were at the least risk. A similar pattern has been observed in the relationship between sleep and coronary heart disease.

Diabetes Care March 2006; 29(3): 657-661
MSNBC March 10, 2006

Cholesterol-Lowering Foods Most Effective When Combined 

Cholesterol-lowering foods such as soy protein, almonds, plant sterol enriched margarines, oats and barley may reduce cholesterol levels more effectively when eaten in combination, says a new University of Toronto study by Professor David Jenkins. The study, which appears in the current issue of the American Journal of Clinical Nutrition, also found that among the subjects who adhered to the diet (one third of test group), this combination of foods reduces low-density lipoprotein cholesterol (”bad” cholesterol) in similar ways as a first generation statin.

“The benefit of statins to individuals at high risk for cardiovascular disease is not in question here,” says Jenkins, a professor in the Department of Nutritional Sciences and a Canada research chair in nutrition and metabolism. “Previous studies have demonstrated that statins can reduce heart disease risk between 25 and 50 per cent.

We don’t, however, know the long-term effects of these drugs when used on a large section of the broader population who are at low risk in primary prevention. Taking a pill may give people the false impression that they have nothing further to do to protect their health and prevent them from making serious lifestyle changes. Emphasizing diet changes in general can boost the success rate of statins while providing additional health benefits and a possible alternative for those for whom drugs are not a viable option.”

Jenkins and his colleagues prescribed a seven-day menu high in viscous fibres, soy protein, almonds and plant sterol margarine to 66 people — 31 men and 35 women with an average age of 59.3 and within 30 percent of their recommended cholesterol targets. For the first time, 55 participants followed the menu under real-world conditions for a year.  They maintained diet records and met every two months with the research team to discuss their progress and have their cholesterol levels measured.

“The participants found it easiest to incorporate single items such as the almonds and margarine into their daily lives,” says Jenkins, who is also staff physician of endocrinology at St. Michael’s Hospital. “The fibers and vegetable protein were more challenging since they require more planning and preparation, and because these types of niche products are less available. It’s just easier, for example, to buy a beef burger instead of one made from soy, although the range of options is improving. We considered it ideal if the participants were able to follow the diet three quarters of the time.”

After 12 months, more than 30 per cent of the participants had successfully adhered to the diet and lowered their cholesterol levels by more than 20 per cent. This rate is comparable to the results achieved by 29 of the participants who took a statin for one month under metabolically controlled conditions before following the diet under real-world conditions.

“The study’s findings suggest that the average person can do a lot to improve their health through diet,” Jenkins says. “People interested in lowering their cholesterol should probably acquire a taste for tofu and oatmeal, keeping in mind that portable alternatives fit best with a modern lifestyle. Save the experimenting for the evening, when you have more time to prepare more complicated meals.”  Jenkins is a leading researcher in the nutritional sciences who developed the glycemic index. His previous studies explored the connections between high-fibre diets, soy foods and heart disease prevention, and meal frequency, vegetarian diets and almonds in reducing cholesterol levels.  

In future studies, he and his colleagues plan to directly compare the benefits of diet against statins over longer periods among individuals at risk for cardiovascular disease across Canada. They will also investigate the effects of incorporating more mono-unsaturated fats into the diet.
University of Toronto

Beat Prostate Cancer by Getting Your Omega-3s 

Foods rich in omega-3 fatty acids may help prevent prostate cancer from spreading.  Omega-6 fats, the kind found in most vegetable oils, increased the spread of tumor cells into bone marrow. However, the spread was blocked by omega-3 fats, suggesting that a diet rich in omega-3 fatty acids could potentially inhibit the disease in men with early stage prostate cancer. Cold water/salt water fish, pumpkin seeds, flak seeds.

Prostate cancer, which is the third most common cancer in men, is more treatable if it is diagnosed before it has a chance to spread.

British Journal of Cancer March 7, 2006
MSNBC March 21, 2006
Food Production Daily.com March 22, 2003

Mental Stress Effects On Heart More Common Than Previously Known 

Even when heart disease patients can pass stress tests done on a treadmill or with chemical stressors after treatment, their hearts may still suffer silent ischemia during mental stress, according to a new study in the Mar. 7, 2006, issue of the Journal of the American College of Cardiology.

“Mental stress induced ischemia is more common than we had recognized,” said David S. Sheps, M.D., M.S.P.H. from the University of Florida and the Malcom Randall Veterans Administration Medical Center in Gainesville, Florida. “It remains to be seen whether that ischemia is also associated in this population with an elevated risk for future health events, as it is in other populations.”  The researchers, including lead author Srikanth Ramachandruni, M.D., monitored heart blood flow in 29 patients as they performed a mentally stressful role-playing scenario. All of the patients had coronary artery disease, but they had been treated and did not show any signs of ischemia (decreased heart muscle blood flow) on either treadmill tests or after an injection with a chemical that puts stress on heart blood flow.

Mental stress has been shown to produce ischemia in heart disease patients who also have problems during exercise or chemical stress tests, but this is the first such study specifically designed to look at this broader group of patients.  The participants were asked to imagine a stressful situation, such as learning that a relative was being mistreated in a nursing home, and then give a short speech demonstrating how they would respond.

None of the patients felt chest pain or other symptoms of ischemia and there were no important differences in heart rate or blood pressure.  But a minute into the speech, a radioactive tracer was injected into the patients. On the images then produced of blood flow in the heart muscle, six of the 29 patients showed signs of ischemia.  ”If we didn’t have the radionuclide imaging procedure, we would not have been able to tell whether the patient actually had ischemia. It’s really totally silent. The patients didn’t have any chest pain,” Dr. Sheps said.

Ischemia produced by mental stress has been associated with an increased risk of health events and death in heart patients who also suffer ischemia during physical stress. Dr. Sheps emphasized that this study just showed that mental stress ischemia can happen even in heart patients who are free of exercise-induced ischemia. The researchers do not know whether the silent ischemia they detected is hazardous to the health of the patients.  ”Nobody has followed the patients that we are talking about in this article. Nobody has followed that population. So we don’t know whether it is predictive in this population or not. It’s an important question,” he said.  The results tend to support proposals that mental stress works through a different mechanism than physical stress. This study did not explore the possible mechanisms, but the researchers noted that some hypotheses include effects on very small blood vessels in the heart muscle or on the endothelium, the inner layer of blood vessels that helps control responses to changes in blood flow.

“The basic message is that psychological stress or behavioral stressors are important. The effects are hard to measure, but several groups of researchers are interested in them and I think we are going to find out a lot more about them in the years to come,” Dr. Sheps said. “We and others are also looking at interventions to try to teach people how to tolerate stress better.”

David S. Krantz, Ph.D., from the Uniformed Services University in Bethesda, Maryland, who was not connected with this study, said this study expands the group of patients who may be vulnerable to the effects of mental stress.  ”It has previously been shown that mental stress can induce myocardial ischemia in a substantial number of coronary artery disease patients.  

The common thinking is that this occurred primarily in patients with positive exercise tests. This study is important because it demonstrates that mental stress ischemia may occur in coronary artery disease patients who don’t have ischemia with exercise. This patient group warrants further study since they may have functionally more severe coronary artery disease that is not shown during standard exercise radionuclide testing,” Dr. Krantz said.
American College of Cardiology

NutraSweet Shown to Cause Cancer 

 The final report of a seven-year study on aspartame (also known as Nutra-Sweet or Equal) has linked it to high rates of lymphomas, leukemia’s, and other cancers in rats. The rats were given the equivalent of four to five bottles of diet soda a day for a human.

The carcinogenic effect of aspartame was found at levels as low as 400 parts per million, or about 20 milligrams a day for humans. This is far less than current daily limits in America (50 milligrams) and the UK (40 milligrams).  When the initial findings were released almost a year ago,they were met with criticism from artificial sweetener trade groups, and support from groups critical of aspartame. No government regulatory agency has yet acted on the findings; there have been calls for a ban in Britain, and the European Food Safety Authority has begun a review of the study’s results. United States FDA officials have said that they also intend to conduct a review.
Environmental Health Perspectives March 2006; 114(3): 379-385
New York Times February 12, 2006

Glycemic Index Deception Finally Understood 

A new study shows that diets based on the glycemic index, like the South Beach Diet, do not effectively control blood sugar levels. The glycemic index, which measures how quickly carbohydrates convert to sugar in your blood, has never been accepted by many dieticians.  This study, which examined food questionnaires from more than 1,000 people over the course of five years, did not find any link between the glycemic index of foods and the blood-sugar levels of participants.

Previous, smaller studies have had different results, including one that seemed to show that a low-glycemic diet lowered risk of heart disease. Supporters of the index claim that foods lower on the index make a person feel full longer and reduce cravings, helping with weight loss.

British Journal of Medicine February 2006; 95(2): 397-405
San Francisco Chronicle March 1, 2006

Coconut Oil 

All tropical oils (palm and coconut) are highly saturated fats. Like butter, cheese, and meat, tropical oils raise LDL cholesterol and clog arteries with plaque, increasing your risk of a heart attack. We use coconut oil (because it is so highly saturated) in animal experiments to create atherosclerotic plaque for studying heart disease in animals. There are different kinds of saturated fats with different impact on LDL cholesterol levels.

One long-chain sat fat, stearic acid, has little impact on LDL cholesterol. But other long-chain saturated fatty acids, like the ones that make up most of the saturated fat in coconut and palm oils (known as tropical oils), do in fact raise LDL cholesterol considerably.  These saturated fats are called palmitic, myristic, and lauric acids. They also make up most of the saturated fatty acids in meat, poultry, and dairy fats like milk and cheese. Other saturated fats that have little impact on LDL cholesterol levels include medium-chain varieties like caproic, caprylic, and capic acids.

A small percentage of the saturated fat in coconut oil, about 10%, is made up of these less harmful saturated fatty acids, but virtually all the rest of coconut oil’s saturated fat is made up of the long-chain varieties that raise LDL.  Coconut oil is getting promoted on the web, internet and even the health food industry, claiming its healthy because most of its fat is made up of medium chain fatty acids (MCT), which are metabolized differently. Yes, it is true that a small portion of coconut oil is MCT (C-6 to C-10 fatty acids) and these do get oxidized more quickly and have little impact on LDL-C levels.

However, because the vast majority of saturated fatty acids in coconut oil are the longer chain fatty acids, C-12 to C-16 (lauric, myristic and palmitic acids) it does in fact elevate LDL-C. The idea that MCT fats will induce weight loss or detoxify the liver is an example of alternative nonsense at its highest level.  Coconut oil is 92% saturated, making it more saturated than butter, beef tallow, or even lard. Palm oil, though it contain less saturated fat (50%), is full of a type of saturated fat, palmitic acid, which appears to be most conducive to heart disease.  The coconut oil industry likes to point out that the traditional Polynesian diet - high in tropical oils like coconut-is linked with relatively low rates of heart disease.

However, it’s important to remember that heart disease involves multiple variables. It is not all fat. The high consumption of fruits, vegetables, fish and the low consumption of cheese and beef obviously are critical in studies of people on traditional Polynesian diets with low rates from heart disease.

Selected segments are reproduced from Dr. Mercola’s excellent website:
http://www.mercola.com/index.htm 

Physicians Committee for Responsible Medicine
http://www.pcrm.org