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Category: nutrition

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Evidence is growing that "mini-fasts" (when food is not eaten) for as little as a 12 hour time period every day is good for the body and may help with weight control. For example, eat supper and then nothing more (but water is OK) till the next day's breakfast - instant 12 hour fast! The second study posted liked a 16 hour mini-fast. From the NY Times:

A 12-Hour Window for a Healthy Weight

Scientists, like mothers, have long suspected that midnight snacking is inadvisable. But until a few years ago, there was little in the way of science behind those suspicions. Now, a new study shows that mice prevented from eating at all hours avoided obesity and metabolic problems — even if their diet was sometimes unhealthful.

Researchers at the Salk Institute for Biological Studies in San Diego and elsewhere began experimenting with the eating patterns of laboratory mice in a previous study. On that occasion, some mice consumed high-fat food whenever they wanted; others had the same diet but could eat only during an eight-hour window. None exercised. The mice that ate at all hours soon grew chubby and unwell, with symptoms of diabetes. But the mice on the eight-hour schedule gained little weight and developed no metabolic problems. Those results were published in 2012.

For the new study, which appeared in the journal Cell Metabolism in December, Salk scientists fed groups of adult males one of four diets: high-fat, high-fructose, high-fat and high-sucrose, and regular mouse kibble. Some of the mice in each dietary group were allowed to eat whenever they wanted throughout their waking hours; others were restricted to feeding periods of nine, 12 or 15 hours. The caloric intake for all the mice was the same.

By the end, the mice eating at all hours were generally obese and metabolically ill, reproducing the results of the earlier study. But those mice that ate within a nine- or 12-hour window remained sleek and healthy, even if they cheated occasionally on weekends. What’s more, mice that were switched out of an eat-anytime schedule lost some of the weight they had gained.

“Time-restricted eating didn’t just prevent but also reversed obesity,” says Satchidananda Panda, an associate professor at the Salk Institute who oversaw the studies. “That was exciting to see.” Mice that consumed regular kibble in fixed time periods also had less body fat than those that ate the same food whenever they chose.

Precisely how a time-based eating pattern staved off weight gain and illness is not fully understood, but Dr. Panda and his colleagues believe that the time at which food is eaten influences a body’s internal clock. “Meal times have more effect on circadian rhythm than dark and light cycles,” Dr. Panda says. And circadian rhythm in turn affects the function of many genes in the body that are known to involve metabolism.

To date, Dr. Panda’s studies have been conducted with only mice, but he says the results seem likely to apply to humans. The upshot: Contain your eating to 12 hours a day or less. And pay attention to when you begin. The clock starts, Dr. Panda says, with “that first cup of coffee with cream and sugar in the morning.”

Another article also liked an "energy restriction period" (mini-fast), but they liked a 16 hour non-eating period.Here is the complete abstract (summary) of the article in Proceedings of the National Academy of Sciences USA,Nov. 25, 2014:

Meal frequency and timing in health and disease.

Although major research efforts have focused on how specific components of foodstuffs affect health, relatively little is known about a more fundamental aspect of diet, the frequency and circadian timing of meals, and potential benefits of intermittent periods with no or very low energy intakes. The most common eating pattern in modern societies, three meals plus snacks every day, is abnormal from an evolutionary perspective. Emerging findings from studies of animal models and human subjects suggest that intermittent energy restriction periods of as little as 16 h can improve health indicators and counteract disease processes. The mechanisms involve a metabolic shift to fat metabolism and ketone production, and stimulation of adaptive cellular stress responses that prevent and repair molecular damage. As data on the optimal frequency and timing of meals crystalizes, it will be critical to develop strategies to incorporate those eating patterns into health care policy and practice, and the lifestyles of the population.

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Good news for those people who enjoy drinking a glass of orange juice each day. From NPR News:

What's More Nutritious, Orange Juice Or An Orange? It's Complicated

We all could probably eat more fruits and vegetables. But if forced to choose between whole fruit or a glass of juice, which one seems more healthful? The general advice is to opt for the fruit, since juices are stripped of the fiber – which most us don't get enough of — in whole fruit. And let's face it: Most juice contains a lot of sugar, which most of us consume too much of.

So our interest was piqued when we spotted a study suggesting that, when it comes to oranges, juice might actually unlock more carotenoids and flavonoids – both beneficial phytonutrients — than an equivalent amount of fruit.

To figure that out, German and Saudi researchers started with a big batch of fresh navel oranges. They analyzed the fruit in three forms: peeled segments, a mashed-up puree and as juice, both fresh-squeezed and pasteurized. They found that levels of vitamin C and carotenoids were basically the same in the juice and the unprocessed fruit, while levels of flavonoids were significantly lower.

But then the scientists threw their orange test foods into in a test tube model designed to mimic digestion, and that's when things got interesting: Much more of the carotenoids and flavonoids were released from the orange juice than from the fruit slices or mush. The differences were striking: Carotenoid release went up from nearly 11 percent in the fruit to 28 percent in the fresh juice, and up to 39.5 percent in the pasteurized juice. Meanwhile, flavonoids were boosted nearly five-fold in juice compared to fruit.

The findings, which appear in the Journal of Agricultural and Food Chemistry, are scientifically intriguing. For example, the researchers suspect heat may have something to do with the extra carotenoids released in pasteurized juice....That said, the new study "is in line with other studies that have found that nutrients in some fruits and vegetables are more bioavailable when the produce is chopped, mashed, juiced or prepared with oils," Blumberg notes in an email to The Salt.

Indeed, there's a whole avenue of research that is challenging our understanding of how to unleash the nutrition fixed inside fruits and veggies. For instance, as we've reported, we get more beta-carotene from tomatoes when we add a little fat like olive oil, and gently cooking carrots can coax them to release more nutrients. And while cooking broccoli for too long can destroy its antioxidants, chopping it is ideal.

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Even though the researchers said this was a "preliminary study"(looking only at non-Hispanic whites), what was good was that results are based on a very large sample size. Coffee drinkers can definitely feel that they are doing something beneficial for their health. From Medical Xpress:

Coffee may be associated with a lower risk of malignant melanoma

Both epidemiological and pre-clinical studies have suggested that coffee consumption has a protective effect against non-melanoma skin cancers. However the protective effect for cutaneous melanoma (malignant and in situ) is less clear, according to a study published January 20 in the Journal of the National Cancer Institute.

To determine if there is an association between coffee consumption and risk of cutaneous melanoma, Erikka Loftfield, M.P.H., of the Division of Cancer Epidemiology and Genetics, National Cancer Institute, and colleagues used data from the NIH-AARP Diet and Health Study. Information on coffee consumption was obtained from 447,357 non-Hispanic white subjects with a self-administered food-frequency questionnaire in 1995/1996, with a median follow-up of 10 years. 

Overall, the highest coffee intake was inversely associated with a risk of malignant melanoma, with a 20% lower risk for those who consumed 4 cups per day or more. There was also a trend toward more protection with higher intake, with the protective effect increasing from 1 or fewer cups to 4 or more. However, the effect was statistically significant for caffeinated but not decaffeinated coffee and only for protection against malignant melanoma but not melanoma in-situ, which may have a different etiology.

The researchers point out that the results are preliminary and may not be applicable to other populations, and therefore additional investigations of coffee intake are needed. 

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This wonderful opinion piece is by Dr. John Mandrola, a cardiologist who also posts on his own blog at http://www.drjohnm.org/ . The bottom line: lifestyle is more important than drugs in preventing heart disease. The following is from Medscape:

Heart Disease and Lifestyle: Why Are Doctors in Denial?

I think and write a lot about the role of lifestyle choices as a treatment strategy. As an endurance athlete, I know that exercise, diet, sleep, and finding balance in life are the key components of success. It is the same in cardiology.

In a randomized controlled trial of primary prevention, no cardiologist would want to be compared against a good physical trainer or nutritionist. We would get trounced. Our calcium scores, biomarkers, pills, and procedures would not stand a chance. The study would be terminated early due to obvious superiority of lifestyle coaching over doctoring—which would blunt the true treatment effect and make us look less bad. (Wink to my epidemiology friends.)

I write a post about new oral anticoagulant drugs or statins or AF ablation, and people pay attention. You see it in the traffic. It's the same story at medical meetings: sessions on drugs and procedures draw the crowds. Late-breaking studies rarely involve the role of exercise or eating well. Exercise, diet, and going to bed on time have no corporate backing. The task of drawing attention to the basics is getting harder, not easier.

And this is our problem. I believe the collective denial of lifestyle disease is the reason cardiology is in an innovation rut. This denial is not active or overt. It is indolent and apathetic. Bulging waistlines, thick necks, sagging muscles, and waddling gaits have begun to look like normal. During the electronic medical record (EMR) click-fest after seeing a patient, I rarely click on "normal" physical exam. The general appearance is abnormal—either overweight or obese.

This is how I see modern cardiology. Our tricks can no longer overcome eating too much and moving too little. We approach health but never get there. If you waddle, snore at night, and cannot see your toes while standing, how much will a statin or ACE inhibitor or even LCZ696 help?

In fact, a reasonable person could make an argument that our pills and procedures might be making patients sicker.

When I started electrophysiology, I mostly treated people with fluky problems. My ablation procedures were on people with supraventricular tachycardia (SVT) due to aberrant pathways. My devices were mostly pacemakers in the elderly—a disease due to aging. These sorts of problems are (mostly) independent of how many sugar-sweetened beverages one drinks.

Now it is different. My practice is dominated by atrial arrhythmia—a disease now recognized as being due (in large part) to excesses of life, such as obesity, high blood pressure, sleep disorders, and overindulgence in alcohol. In other words: unnecessary. I make hundreds of dollars putting a hundred burns in a left atrium for a disease that a poorly paid physical trainer might prevent or treat. This has become cardiology writ large.

But the thing I cannot get over is that I am doctor, not a proceduralist. I am tasked with helping people be well. I fail in that task if I ignore the most effective and safest treatment option. I fail if I take the easy path. The prescription pad is easy. The EP lab is easy. The truth is hard... New anticoagulant drugs are easy. Ablation technology is easy. Statins are even easier. The truth—nutrition, exercise, balance in life—is hard.

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I bet eating fresh blueberries daily instead of blueberry powder would not only be more delicious, but also have even more health benefits. From Science Daily:

Blueberries may help reduce blood pressure and arterial stiffness

Just one cup of blueberries per day could be the key to reducing blood pressure and arterial stiffness, both of which are associated with cardiovascular disease. .... Johnson said she is interested in looking at how functional foods -- foods that have a positive impact on health beyond basic nutrition -- can prevent and reverse negative health outcomes, particularly for postmenopausal women.

Over an eight-week period, 48 postmenopausal women with pre- and stage-1 hypertension were randomly assigned to receive either 22 grams of freeze-dried blueberry powder -- the equivalent to one cup of fresh blueberries -- or 22 grams of a placebo powder. Participants, meanwhile, continued their normal diet and exercise routines.

At the end of the eight weeks, participants receiving the blueberry powder on average had a 7 mmHg (5.1 percent) decrease in systolic blood pressure, which is the top number in the blood pressure reading that measures the pressure in the arteries when the heart beats. They also saw a 5 mmHg (6.3 percent) reduction in diastolic blood pressure, or the bottom number measuring the pressure in the arteries between heartbeats.

Additionally, participants in the blueberry-treated group had an average reduction of 97 cm/second (6.5 percent) in arterial stiffness.They also found that nitric oxide, a blood biomarker known to be involved in the widening of blood vessels, increased by 68.5 percent. That is important, Johnson said, because arterial stiffness and the narrowing of blood vessels are both a part of hypertension. This rise in nitric oxide helps explain the reductions in blood pressure.

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From Science Daily:

More whole grains associated with lower mortality, especially cardiovascular

Eating more whole grains appears to be associated with reduced mortality, especially deaths due to cardiovascular disease (CVD), but not cancer deaths, according to a report.

Whole grains are widely recommended in many dietary guidelines as healthful food. However, data regarding how much whole grains people eat and mortality were not entirely consistent.

Hongyu Wu, Ph.D., of the Harvard School of Public Health, Boston, and coauthors examined the association between eating whole grains and the risk of death using data from two large studies: 74,341 women from the Nurses' Health Study (1984-2010) and 43,744 men from the Health Professionals Follow-Up Study (1986-2010). All the participants were free of cancer and CVD when the studies began.

The authors documented 26,920 deaths. After the data were adjusted for potential confounding factors including age, smoking and body mass index, the study found that eating more whole grains was associated with lower total mortality and lower CVD mortality but not cancer deaths. The authors further estimated that every serving (28 grams/per day) of whole grains was associated with 5 percent lower total mortality or 9 percent lower CVD mortality.

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Take note: the focus should be on getting magnesium from foods, not supplements. As the researchers warn: "your body absorbs magnesium from food differently than it does from supplements". From CNN:

Magnesium, an invisible deficiency that could be harming your health

Feeling exhausted? Or noticing weird muscle cramps that are throwing off your workouts? You might be suffering from a magnesium deficiency. Dubbed the "invisible deficiency" by some experts because it's so hard to spot and diagnose, magnesium deficiencies are more dangerous than you might think. "Magnesium is involved in over 300 biochemical reactions in your body. It affects everything from your heartbeat to your muscles to your hormones," says Dr. Danine Fruge, Associate Medical Director at the Pritikin Longevity Center in Miami, Florida.

 "Studies have shown that only about 25% of U.S. adults are at or above the recommended daily amount of 310 to 320 milligrams for women and 400 to 420 for men," says Fruge. In fact, the 2005-2006 National Health and Nutrition Examination Survey (NHANES) revealed that at least half of the U.S. population had inadequate intakes of magnesium.

Loss of appetite, nausea, fatigue -- the initial symptoms of magnesium deficiency are also common side effects of other health conditions, making it difficult to diagnose. This sneaky disorder manifests in three different stages, depending on how lacking you are in the nutrient. While initially symptoms can be minor, a magnesium deficiency may eventually cause noticeable problems with your muscle and nerve function such as tingling, cramping, numbness and contractions (like that annoying eye twitch you just can't shake). In its worst stages, magnesium deficiency could even cause seizures, personality changes, or abnormal heart rhythms.

To make matters scarier, this condition can be difficult to detect with medical tests. Since only 1% of magnesium is found in your blood (most is in your bones or organs), a simple needle prick often won't help determine your levels. Instead, Fruge says diagnoses are usually made through process of elimination and by examining a patient's lifestyle.

It may be what you're eating — rather than what you're not eating — that's putting you at risk for magnesium deficiency. "It's very easy to get enough magnesium. I think the reason so many people are deficient is because a lot of food and drink can make magnesium unavailable to their bodies," says Fruge. The main culprits: soda, caffeinated beverages and alcohol, according to Fruge... Consuming too much alcohol can interfere with your body's absorption of vitamin D, which aids magnesium absorption. As for food, refined sugar causes the body to excrete magnesium through the kidneys, resulting in a net loss, according to Fruge.

Plus, your body absorbs magnesium from food differently than it does from supplements. You should only use magnesium supplements under the direction of a doctor — and be sure not to exceed 350 non-food milligrams of magnesium per day (unless a medical professional instructs you differently). "Your body has built-in mechanisms that don't allow it to overdose from food, but that doesn't exist for supplements. Too much magnesium via supplement can put your heart into an arrhythmia and that can even be fatal, particularly for people with issues like diabetes," says Fruge.

Food sources are your safest bet so focus on amping up your consumption of leafy greens — one cup of cooked spinach provides 157 milligrams of magnesium. Legumes are a solid choice too, with a cup of cooked white beans coming in at 113 milligrams of the nutrient. And if you're a fan of squash and pumpkin seeds, one cup packs in a whopping 649 milligrams. Other great options are nuts, including almonds and cashews, most types of fish, and whole grains.

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Great news for coffee lovers, especially for those drinking 3 to 5 cups daily! From Medical Daily:

Drinking Coffee Can Lower Alzheimer's Risk By 20%, All It Takes Is 3 Cups A Day

As if you weren’t already drinking a lot of coffee, a review of several studies has found drinking three to five cups a day could reduce risk of Alzheimer’s disease by 20 percent.

The research was presented at the 2014 Alzheimer Europe Annual Congress, and found that people who drank coffee regularly — all you lifers out there — were less likely to develop the debilitating disease. Alzheimer’s, perhaps the worst type of dementia, is a progressive disease that works slowly, first making it difficult to remember newly learned things, and later on making it difficult to remember early memories and family member’s faces, while also causing hallucinations. The biggest risk factor for the disease is being over 65 years old.

Roughly 83 percent of American adults drink coffee, according to the National Coffee Association. What many of these Americans don’t know, however, is that inside that cup of Joe is a wealth of polyphenols, which you probably know as antioxidants. These antioxidants — researchers said they’re the same ones found in the Mediterranean diet — prevent the formation of a hallmark of Alzheimer’s disease known as amyloid plaques and neurofibrillary tangles, the study found. They also reduce inflammation and deterioration of brain cells, particularly in the areas of the brain (the hippocampus and cortex) responsible for memory.

Along with prevention of Alzheimer’s, coffee has been linked to a reduced risk of liver cancer and other liver conditions, a lower risk of type 2 diabetes; it prevents eye damage and Parkinson’s disease; and even boosts endurance. But even then, drinking too much isn’t good, either. As the researchers noted, three to five cups is optimal; anything over that, and you might find yourself with some problems.

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Of course! From Science Magazine:

Guts of obese dogs look similar to those of obese people

Obese people have a less diverse array of bacteria living in their guts than do thin people—and the same holds true for dogs. In a new study, researchers fed seven beagles unrestricted amounts of food for 6 months, during which each dog gained an average of 4.93 kilograms—about 67% of their initial average weight of 7.37 kilograms. The investigators fed another seven beagles controlled food portions, and, as expected, this group did not gain weight.

When the researchers examined the fecal samples collected from both groups after 6 months, they found that the guts of obese beagles contained a smaller diversity of bacteria than those of the other dogs. What’s more, microbes from the phylum Firmicutes were the predominant group in the lean dogs, whereas Gram-negative bacteria called Proteobacteria were prevalent in the obese group, the team reported online this month in the Journal of Veterinary Internal Medicine. The researchers speculate that an abundance of Proteobacteria may lead to an increase in lipopolysaccharide, a major component of the cell wall of Gram-negative bacteria, which has been linked to weight gain in mice. More research is needed to examine what role gut bacteria may play in the development of obesity, however, the authors say.

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Further reasons to try to consume foods and beverages from glass containers and avoid cans and plastic bottles. Note that the BPA caused changes within 2 hours, and that BPA-free alternatives may be no better than BPA. Some researchers are speculating whether the high incidence of hypertension is linked to the prevalence of BPA in our environment. From Medical Xpress:

Cans lined with Bisphenol A may increase blood pressure

Drinking or eating from cans or bottles lined with Bisphenol A (BPA) could raise your blood pressure, according to new research reported in the American Heart Association's journal Hypertension. BPA, a chemical used as an epoxy lining for cans and plastic bottles, is everywhere, and its consumption has been associated with high blood pressure and heart rate variability. Previous studies have shown that BPA can leach into foods and drinks.

"A 5 mm Hg increase in systolic blood pressure by drinking two canned beverages may cause clinically significant problems, particularly in patients with heart disease or hypertension," said Yun-Chul Hong, M.D., Ph.D., study author... "A 20 mm Hg increase in systolic blood pressure doubles the risk of cardiovascular disease."

In this study, researchers conducted a randomized crossover trial recruiting 60 adults, mostly Korean women, over the age of 60 from a local community center. Each trial member visited the study site three times and was randomly provided with soy milk in either glass bottles or cans. Later urine was collected and tested for BPA concentration, blood pressure and heart rate variability two hours after consumption of each beverage.

Urinary BPA concentration increased by up to 1,600 percent after consuming canned beverages compared to after consuming the glass-bottled beverages.. Soy milk was the ideal beverage for the test because it has no known ingredient that elevates blood pressure, researchers said.

UPDATE: The NY Times has a nice write-up of this research with further details:

BPA in Cans and Plastic Bottles Linked to Quick Rise in Blood Pressure

A single instance of increased blood pressure may not be particularly harmful. But the findings suggest that for people who drink from multiple cans or plastic bottles every day, the repeated exposure over time could contribute to hypertension, said Dr. Karin B. Michels, an expert on BPA who was not involved in the new research.

BPA has been used since the 1960s to make countless everyday products like plastic bottles, food containers, contact lenses, and even sippy cups and baby bottles. The chemical can leach into food, and studies show that the vast majority of Americans who are tested have BPA in their urine.

The chemical is an endocrine disrupter that can mimic estrogen. In 2012, the Food and Drug Administration said BPA could no longer be used in baby bottles and children’s drinking cups. Canadian regulators formally declared BPA a toxic substance in 2010 and banned it from all children’s products.

Because of growing consumer concerns, some bottles and packaged food products now carry “BPA free” claims on their labels. However, these products often contain chemically similar alternatives – like bisphenol S. One study in the journal Environmental Health Perspectives found that plastic products advertised as BPA-free still leached chemicals with estrogenic activity – and some of these chemicals were even more potent than BPA.