Archive for Research
Weight loss diets and macronutrient composition
Posted by: | CommentsFrom Medscape:
The quick summary: “Dieters ate different amounts of protein, fat, and carbohydrate — but, after 2 years, most were still obese.”
Here’s some more detail: “While weight-loss diets claim unique nutrient compositions that guarantee unusually rapid and effortless success, comparative studies — usually with small populations and short follow-ups — have yielded widely disparate results. Now, a large long-term multisite study suggests that all these diets result in similar outcomes.
Researchers randomized 811 overweight adults (81% white; 62% female; 69% college graduates; mean body-mass index, 33 kg/m2) to four restricted-calorie eating plans:
* High fat, high protein
* High fat, average protein
* Low fat, high protein
* Low fat, average protein
Carbohydrate intake ranged from 35% (in the first plan) to 65% (in the fourth) of total calories. All meals were prepared at home, and participants ate from a single menu with each dish’s components adjusted to reflect each diet’s emphasis; all participants were offered weight-loss counseling.
Changes in weight and waist circumference at 6, 12, 18, and 24 months were indistinguishable among groups: At 2 years, only about 15% of each group had lost at least 10% of body weight. Attendance at group counseling sessions strongly predicted successful weight loss. At 2 years, hunger and diet-satisfaction scores were all similar. Food diaries and urinary nitrogen analyses indicated that the actual nutrients consumed might have been more similar among groups than had been planned.”
I think that this situation is to be expected. Deprivation, as a general rule, is extremely hard to maintain over the long haul. It’s better to gradually change by learning how to eat plant-based, whole foods. Bottom line: its not the macro-nutrient balance that counts. It’s the micro-nutrients (and of course physical activity) that ultimately determine health and fitness.
Waist size as a health indicator
Posted by: | CommentsAccording to a study to be published in the Journal of the American College of Cardiology, waist circumference (and a related index, waist to hip ratio) are better indicators of cardiovascular problems than body mass index (BMI), which is currently the measure used to define obesity. BMI alone might not be strongest predictor of coronary disease. The researchers found that subjects with the highest waist-to-hip ratio had a twofold increase in the incidence of calcium deposits, which is highly correlated with future cardiovascular problems such as heart attacks.
“Fat that accumulates around your waist seems to be more biologically active as it secretes inflammatory proteins that contribute to atherosclerotic plaque buildup, whereas fat around your hips doesn’t appear to increase risk for cardiovascular disease at all,” according to senior author Dr. J. de Lemos said. “We think the key message for people is to prevent accumulation of central fat early on in their lives. To do so, they will need to develop lifelong dietary and exercise habits that prevent the development of the ‘pot belly.”
Brain health and aging
Posted by: | CommentsThe secret to keeping our mind intact as we age? Research sponsored by the MacArthur Foundation Network on Successful Aging shows that there are four variables that affect mental fitness: physical activity, lung function, levels of education, and feelings of self-efficacy. The scientists believe that that regular exercise stimulates flow to the brain and promote nerve growth. This results in denser neuronal networks that are more resistant to disease. Moderate aerobic workouts can accomplish this.
Animal studies also support the hypothesis that mental and physical activity enhance brain health. The Beckman Institute for Advanced Science and Technology in Urbana, Illinois found that rats developed 25 percent more connections between their neurons compared to rats that did not get any mentally stimulating tasks. Rats that exercised on a treadmill developed more capillaries in their brains (which increased the flow to their brains) versus their couch potato peers.
Plant-based omega-3
Posted by: | CommentsA study from from King’s College London has found that relatively small amounts of omega-3 fatty acids from algae (even as little as 0.7 grams of DHA) can lower pressure and reduce the risk of cardiovascular disease. Unlike fish oil, has the advantage of being both sustainable and acceptable to vegetarians.
The omega-3 fatty acid docosahexaenoic acid (DHA) was extracted from the marine algae crypthecodinium cohnii. Results showed that the daily intake of 0.7g DHA lowered diastolic pressure by 3mm of Hg. This reduction can prevent thousands of heart attacks and strokes.
Previous studies using fish oil required more than 2-3g of omega-3 fatty acids to lower pressure. Fish oil generally contains more eicosapentaenoic acid (EPA) than DHA. This study shows that even relatively small amounts of DHA can effectively improve cell membrane function and lower pressure. Omega-3 fatty acids are considered essential fatty acids. They are manufactured by the body and must be obtained from fish and certain plant sources. Many studies show that omega-3 fatty acids reduce inflammation, help prevent certain chronic diseases (e.g., heart disease, arthritis) and play a critical role in brain function.
‘Our findings provide further evidence that relatively small amounts of this form of omega-3 helps promote a healthy heart,’ said T. Sanders, Head of King’s College London’s Nutritional Sciences Research Division. ‘There are long-term worries about the sustainability of fish stocks and our results suggest that a sustainable vegetable source synthesised by algae may be useful for preventing cardiovascular disease. Importantly, this form of DHA is acceptable to people who do not eat fish, for example vegetarians.’
Omega mind
Posted by: | CommentsOmega-3 polyunsaturated fatty acids can affect mood, personality and behavior, according to a study by University of Pittsburgh School of Medicine.
In a study of 106 healthy volunteers, researchers found that participants who had lower levels of omega-3 polyunsaturated fatty acids were more likely to report mild or moderate symptoms of depression, a more negative outlook and be more impulsive. Conversely, those with higher levels of omega-3s were found to be more agreeable.
Wine and heart health
Posted by: | CommentsHeart rate variability (HRV) measures the changes in time intervals between the beats of the heart. Decreased HRV has been associated with an increased risk of heart disease and death.
A study of female heart attack survivors completed in 2005 showed that HRV was highest in those who drank 5 or more grams of alcohol a day, equivalent to more than half a standard unit, and lowest in those who drank no alcohol at all. Further analysis showed that the type of alcohol consumed was important. HRV was highest among women who drank wine, even after taking account of other influential factors, such as age, weight, and smoking habit. Beer and spirits had little impact on HRV. Perhaps the favorable effects on HRV may be one of the reasons why wine protects heart health.
There’s a new study claiming that lowering blood pressure (BP) below the standard 140/90 (systolic/diastolic) is not beneficial. While this has been the de facto BP target of physicians and patients, there has been a trend towards lower targets by hypertension experts setting treatment guidelines. According to the study, “using more drugs in lower target groups did achieve modestly lower BP. However, this strategy did not prolong survival or reduce stroke, heart attack, heart failure or kidney failure. At present there is no evidence to support aiming for a BP target lower than 140/90 in any hypertensive patient.”
It’s very easy to take this study out of context. Notice that the study refers to the use of anti-hypertensive drugs to lower BP. There is a vital difference between using drugs to lower BP and using lifestyle measures (i.e., a plant based diet, exercise, and maintaining a healthy body weight).
What the study is saying is that if one is using BP-lowering drugs, it’s not worth it to take more drugs in order to go below 140/90. The study is NOT saying that 140/90 is a “healthy” metric. Neither is it refuting the benefits of a healthy diet and lifestyle approach that results in levels like 115/70. (The current article in Medscape cites the Lewington meta-analysis of one million patients showing convincing evidence that people have fewer strokes and heart attacks when their ‘usual’ BP is 115/70 compared with those with a ‘usual” BP of 130/90).
It is simply saying that pumping more drugs simply to lower BP beneath 140/90 is marginally effective.
I like to think of BP as an “effect” (or “dependent variable,” in research-speak). The cause (or independent variable) of the metric is actually how we eat and live. The better we eat, the more consistently we exercise intelligently, the better our BP fares. What has happened in today’s medicalist gestalt is that we tend to confuse BP (or some other metric) as the “root cause” of the disease, and therefore any intervention (i.e., medication) that causes BP to go lower is “good.” We’re targeting the symptom, rather than the cause of the disease itself.
This is not to knock antihypertension medication, or any “symptom targetting” protocol (such as statins for high cholesterol). Ultimately, what we need to address are the basic issues causing the symptoms in the first place. In the majority of cases, the causes would be being overweight or obese, lack of exercise, and eating a nutrient-poor, calorie dense diet.
The medical “business model” in a nutshell
Posted by: | CommentsIn an eight-year study published in the Journal of the American College of Cardiology, high levels of myeloperoxidase (MPO) were closely associated with the early development of heart disease. MPO is a protein secreted by white cells. It signals inflammation and releases a bleach-like substance that damages the cardiovascular system. Its predictive abilities were independent of classic risk factors such as high cholesterol, high pressure and diabetes.
“A high MPO reading now indicates that the physician should concentrate on reducing known risk factors, but MPO itself could eventually become a target of treatment, according to Dr. Stanley L. Hazen, head of the section of preventive cardiology and cardiac rehabilitation at the Cleveland Clinic.”
How absurd is this??
Why will the marker be the target of the treatment? Why would a healer merely try to fix the symptom? The profit model involved here is quite clear. Find a “quantifiable” symptom. Create a chemical that controls the level of the symptom. Sell the chemical. Make money.
Why can’t we focus on the the cause of the high MPO in the first place?
This is really no different from the cholesterol-statin profitability dynamic. “High cholesterol levels are correlated to cardiac problems. Ergo, control the numbers by giving the patient a cholesterol lowering substance .” Why not just attack the root cause of the high cholesterol itself — i.e., a faulty diet and a lifestyle of sustained overconsumption and imbalance?
Green leafy vegetables and cognitive decline
Posted by: | CommentsEating vegetables slows down the rate of cognitive decline in older s, according to a study published in the October 24, 2006, issue of Neurology. “Compared to people who consumed less than one serving of vegetables a day, people who ate at least 2.8 servings of vegetables a day saw their rate of cognitive change slow by roughly 40 percent, said author Martha Clare Morris, ScD, associate professor at Rush University Medical Center in Chicago, Illinois. “This decrease is equivalent to about 5 years of younger age.”
Green leafy vegetables had the strongest effect on slowing the rate of cognitive decline. The older the person, the slower the cognitive decline was — if that person consumed more than two servings of vegetables a day.
Per calorie, green leafy vegetables are the critical mainstays of a powerful restorative diet. Kale, collard, mustard greens, dandelions, watercress, brocolli rabe — these are excellent steamed and accompanied by a cup of thick dal (see my “standardal” recipe in an earlier post), topped with finely ground (for better absorption) high protein seeds like sunflower and sesame. This is one of my typical easy-to-fix dinners, btw.
You can really feel the energy difference, if you try this regularly. Very good habit to develop.
Weight loss strategies from the masters of weight control
Posted by: | CommentsFrom the National Weight Control Registry (people who have successfully lost more than 30 pounds and kept it off for a year): “Almost all patients who successfully maintained long-term weight loss used both diet and physical activity to lose weight. These people also shared strategies for maintaining the weight loss: eating a low-fat, high-carbohydrate diet; eating breakfast almost every day; weighing themselves frequently; and engaging in 60 to 90 minutes per day of moderate-intensity physical activity. Although we do not know for certain, we think that this behavior probably led to their success in keeping weight off. These characteristics could be effectively used as components of programs for helping overweight and obese people to achieve and maintain weight loss.”
