Saturday, June 26, 2010

When Food and Pills Clash


Fresh Concerns on How Diet and Medicines Interact, From Pepper to Pomegranate

Americans increasingly view the food they eat as medicine to help lower cholesterol, reduce high blood pressure and control blood sugar. But as with prescribed drugs, the health-improving qualities of foods such as olive oil, nuts and fruit can interact with other medications, causing possible problems.

Pharmacists often warn people not to mix anti-cholesterol drugs known as statins with grapefruit juice. Newer research suggests that other fruit juices, including cranberry and pomegranate, as well as olive oil may also interfere with how statins work in the body. Other laboratory studies show that certain popular teas can block the effect of some medications, including the flu drug Tamiflu. And switching to a low-fat diet, itself a healthy lifestyle change, could reduce the potency of some medications.

http://online.wsj.com/article/SB10001424052748704256304575320743052254682.html?KEYWORDS=shirley+s+wang#articleTabs%3Darticle
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When ingested, ginger can help to relieve muscle pain.

Pain Relief: Ginger appears to reduce exercise-induced muscle pain, according to a study in the Journal of Pain. Researchers randomly assigned 74 adults to consume two grams of either ginger (raw in one experiment and heat-treated in another) or a placebo for 11 consecutive days. On the eighth day, the participants performed series of bicep exercises tailored to mildly damage the muscle in their non-dominant arm. One day later, participants who had been given ginger reported feeling about 25% less pain, on a scale from "no pain" to the "most intense pain imaginable," than subjects in the placebo group. Though the precise pain-fighting mechanism is unknown, animal studies have shown that several chemicals in ginger reduce inflammation and the transmission of pain signals. The results also jibe with previous trials of smaller doses of ginger extract over a longer treatment period, which reportedly reduced joint pain in arthritis patients.

Caveat: By the second day after the exercise, the differences in pain between the test groups were statistically insignificant.

Wednesday, June 23, 2010

Excess Salt, and a Way to Avoid It

Excess Salt, and a Way to Avoid It
Published: June 4, 2010
Readers respond to a recent article on salt.
http://www.nytimes.com/2010/06/06/opinion/l06salt.html

Sunday, June 6, 2010

The Claim: Rosemary Helps Reduce Toxins in Grilled Meat

By ANAHAD O'CONNOR

THE FACTS

Cooking meat at high temperatures is known to create toxins called heterocyclic amines, which have been linked to some cancers. Marinating lowers the risk by preventing the formation of the toxins. But one ingredient that makes a big difference is rosemary. Studies show that adding it to ground beef and other types of muscle meat before grilling, frying, broiling or barbecuing significantly reduces heterocyclic amines.

In a study published in The Journal of Food Science in March, scientists tested extracts of rosemary on ground beef patties that were cooked at temperatures from 375 degrees to 400 degrees Fahrenheit. The extract was added to both sides of the meat before cooking. The higher the concentration, the greater the reduction in heterocyclic amines (in some cases by over 90 percent.

Scientists attribute this to specific antioxidants in rosemary: rosmarinic acid, carnosol and carnosic acid. Another study two years ago compared several marinades and found that the one that was most protective was a Caribbean mixture, which, they wrote, “contained considerable amounts” of the same three antioxidants.

If rosemary is not your thing, or you have an allergy, try marinades with garlic, onion and lemon juice. They have also been shown in studies to be effective (garlic and onion much more so than lemon juice).

THE BOTTOM LINE

Studies show that marinades with rosemary help eliminate some carcinogens in grilled meat.

scitimes@nytimes.com

Regimens: Eat Your Vegetables, but Not Too Many

They say you can never be too rich or too thin. But is it possible to eat too many leafy green vegetables?

Last year, an 88-year-old woman was admitted to NYU Langone Medical Center in a nearly comatose state, unable to walk or swallow and barely able to breathe. Though she had no history of thyroid disease, she was given a diagnosis of myxedema coma a life-threatening condition caused by extreme hypothyroidism, or low thyroid function.

The culprit, it turned out, was raw bok choy. The patient had been eating two to three pounds of it every day for several months, in the belief it would help control her diabetes. Instead, the vegetables may have suppressed her thyroid, according to NYU physicians who described the case in a letter in the May 20 issue of The New England Journal of Medicine.

Bok choy contains compounds called glucosinolates that have been found to inhibit thyroid function in animals.

“I don’t want to say people shouldn’t be eating raw vegetables, but everything in moderation — even things that are good for us,” said Dr. Michael Chu, an NYU resident physician who was one of the letter’s authors. “This probably wouldn’t have happened if the vegetables were cooked.”

Sunday, May 23, 2010

Blueberries Slow Tumor Growth

Blueberry extract slows the spread of a difficult-to-treat form of breast cancer, according to a small study of mice in Cancer Research. So-called triple-negative breast cancers, which account for 10% to 15% of all breast-cancer cases, lack the three receptors that most cancer drugs target. In a preliminary test-tube experiment, researchers discovered that blueberry extract, compared with other fruit and vegetable extracts, had the greatest effect on these tumors without harming healthy cells. The researchers randomized 16 mice to receive either blueberry extract—a daily dose of unadulterated juice extracted from blueberries that was roughly equivalent to five ounces of blueberries a day for a 150-pound person—or a placebo. One week after the first dose, the mice were injected with triple-negative breast-cancer cells. Six weeks after that, necropsies revealed that the tumors of blueberry-fed mice were about 70% smaller than those in placebo-fed mice. The tumors of the blueberry-fed mice also had less potential to spread to other parts of the body.

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Caveat: Many successful cancer-fighting therapies in mice have been difficult to replicate in humans.

Read the Study: Blueberry Phytochemicals Inhibit Growth and Metastatic Potential of MDA-MB-231 Breast Cancer Cells through Modulation of the Phosphatidylinositol Kinase Pathway

• Emotional Memory: Emotions can outlast the memory of the facts on which those feelings are based, according to a study of amnesiac patients in Proceedings of the National Academy of Sciences. Five patients with severe anterograde amnesia, which largely prevents the creation of new memories, watched a 19-minute video of film clips about death and loss. (The clips included scenes from "Sophie's Choice" and "Forrest Gump.") Several times during the study, researchers asked the subjects how they felt. Five to 10 minutes after the final scene, the amnesiacs remembered nearly nothing they had seen. They were asked to rate their emotions on several scales, including to what degrees they felt happy, sad, amused and "bad/unpleasant" versus "good/pleasant". The responses showed that the amnesiacs' negative emotions were stronger and lasted longer, than a control group of subjects who had no brain damage. The researchers repeated the experiment with humorous film clips, finding that positive emotions also outlasted specific memories. The results contradict the popular concept that "erasing" painful memories can ease the distress associated with those memories, the researchers said

Caveat: Larger studies are needed to confirm the findings. It's unclear whether emotions are equally persistent among people with other forms memory loss, such as Alzheimer's.

Read the Study: Sustained experience of emotion after loss of memory in patients with amnesia

• Pregnancy: Weight-reduction surgery appeared to reduce obese women's odds for blood-pressure disorders during future pregnancies, according to a study in BMJ. Obesity is a major risk factor for pregnancy-related hypertensive disorders, which can cause low birth weight and premature birth, as well as increase the mother's risk for cardiovascular and kidney diseases. Researchers examined insurance claims from 585 U.S. women who had weight-loss surgery and gave birth within a four-year window. About half of the women underwent the surgery before giving birth, with an average of two years between the two events. Fewer than 10% of these women experienced pre-eclampsia (a sudden spike in blood pressure and in protein in the urine) and other hypertensive disorders during pregnancy, while these complications occurred in 31% of women who delivered before weight-reduction surgery. Women who delivered pre-surgery were twice as likely to develop gestational diabetes, which may lead to Type 2 diabetes later in life.

Caveat: Researchers relied on insurance claims and didn't have access to the mothers' height, weight or blood pressure. They also were unable to link the data on mothers to their infants' health.

Read the Study: Impact of bariatric surgery on hypertensive disorders in pregnancy: retrospective analysis of insurance claims data;

• Immune Responses: Visual signs of disease, independent of physical proximity, appear to jump-start our immune systems, according to a study in Psychological Science. Researchers took blood samples from 28 subjects before and after they watched a 10-minute slide show depicting photographs of furniture, a neutral subject. Later, the researchers divided the same subjects into two groups; one watched a slide show of visible disease symptoms—including pictures of people sneezing or infected with skin lesions—while the other group saw photographs of guns. The white blood cells of participants in the first group produced nearly 24% more interleukin-6, a protein used to judge immune response, after seeing the photographs of disease. There was no statistically significant increase, however, in interleukin-6 after the furniture or gun slide shows.

Caveat: The study was small. It's unclear what effect these cues have in a non-laboratory setting, or in relation to other sensory signals.

• Emergency Care: Uninsured patients who have a heart attack, despite being guaranteed treatment, take significantly longer to arrive at the hospital than insured patients, according to a study in JAMA. Greater delays between a heart attack and hospital treatment decrease the odds of survival, previous studies have shown. Researchers in this study examined the medical records of 3,721 heart attack patients at 24 U.S. hospitals, and then interviewed them about their insurance status and financial concerns. One-fifth of all participants were uninsured. Of those, more than 48% arrived at the hospital six hours or longer after the heart attack occurred, compared with 39% of insured patients without financial concerns about their coverage, and about 45% of insured patients with financial concerns. After adjusting for a host of factors such as age and disability, the researchers determined that delays were nearly 40% more likely among uninsured patients than among patients with insurance and no financial concerns.

Caveat: Traffic and geographic distance from the hospital likely affected these delays, but the researchers were unable to collect this data. The researchers also didn't determine whether lack of insurance was a factor in patients themselves delaying going to the ER. The study was conducted solely in urban areas, so the findings don't necessarily apply to other regions.

Read the Study: Health Care Insurance, Financial Concerns in Accessing Care, and Delays to Hospital Presentation in Acute Myocardial Infarction

• Sexually Transmitted Infections: Human papillomavirus, known for its link to cervical cancer and other tumors, appears also to increase the risk of HIV infection, according to a study in PLoS ONE. Researchers followed 2,040 HIV-negative Zimbabwean women for approximately two years. Every three months, the women were tested for HIV and 29 known strains of HPV. About one-quarter of the women had HPV at the beginning of the study. By the end of the study, 88 women (4.3%) developed HIV. But women who began with either of two particular HPV strains were twice as likely as other women to acquire HIV. Remarkably, women with the least persistent HPV infections were the most likely to get HIV. These findings suggests that the immune response to HPV—rather than abnormal cell growth—predisposes women to HIV infection, the researchers said.

Caveat: Unlike other strains of HPV, vaccines aren't available for the types associated with HIV infection. The researchers were unable to distinguish between biologically active HPV and inactive virus DNA deposited by a recent sexual partner.

Read the Study: Type-Specific Cervico-Vaginal Human Papillomavirus Infection Increases Risk of HIV Acquisition Independent of Other Sexually Transmitted Infections

• Migraines: Aspirin can provide adequate relief for many migraine sufferers who lack access to prescription medication, according to meta-analysis by the Cochrane Library. The authors analyzed results from 4,222 participants in 13 studies that compared the effectiveness of aspirin—alone or in tandem with a generic anti-nausea drug—with a placebo. Within two hours, one-gram doses of aspirin reduced the severity of migraine headaches in 52% of participants, while a placebo worked for only one-third of migraneurs. Aspirin also significantly reduced nausea and vomiting, which the addition of the anti-nausea drug further diminished.

Caveat: Frequent aspirin use can cause stomach and intestinal ulcers, and may contribute to hearing loss and other symptoms. As with all meta-analyses, the underlying studies have their own limitations.

Read the Study: Aspirin with or without an antiemetic for acute migraine headaches in adults

• Digestion: An intestinal bacterium apparently abundant among Japanese has evolved to improve the digestion of seaweed, according to a study in Nature. The human gut harbors trillions of bacteria, many of which help digest molecules that human enzymes cannot. Researchers identified a new class of enzyme that breaks down porphyran, a carbohydrate found exclusively in red algae. They then tested intestinal bacteria samples from 13 Japanese volunteers and 18 North American volunteers for the genetic sequence that creates the porphyran-breaking enzyme. The gene was common in the Japanese samples, but entirely absent from the North American samples. This string of DNA likely migrated from marine microbes to intestinal bacteria, though it's difficult to estimate when this happened, the researchers said.

For Nut Benefits, More Is Better Two handfuls a day may do more to lower blood cholesterol and triglycerides than one

More research backing up the cholesterol-lowering benefits of eating nuts indicates that for most people, consuming two handfuls of nuts a day appears to work better than one.

The findings apply to tree nuts such as walnuts, almonds, pistachios, macadamias, hazelnuts and peanuts.

Although peanuts actually belong to the legume family, they are considered to have many of the same nutritional components as walnuts, almonds and other tree nuts.

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Researchers found that, for the average person, about two servings of tree nuts did a better job of reducing blood cholesterol and triglycerides than one serving. Researchers who examined the results of 25 previous studies on the health effects of nut consumption found a dose-related improvement in participants' blood-lipid levels.

The results are published this week in the Archives of Internal Medicine.

The lead author of the latest research, Joan Sabaté, says the study "confirms that nuts, indeed, lower cholesterol." A professor and the chairman of the department of nutrition at Loma Linda University, in Loma Linda, Calif., Dr. Sabaté was among the group of researchers that first linked nut consumption to a lower risk of heart attack several years ago.

That finding and others led the Food and Drug Administration in 2003 to allow processors to state on labels that "eating 1.5 ounces per day of most nuts ... as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease."

Dr. Sabaté said the research indicated that for the average person, a slightly higher amount of nuts—about 2.4 ounces, or two servings—does a better job than one serving of lowering cholesterol and triglycerides, another type of fat in the blood.

Still, he said, "we do not need many to get the benefit." One serving of almonds is about eight nuts; a serving of smaller nuts such as peanuts is about 15 to 20 nuts.

Dr. Sabaté's analysis involved nearly 600 people with high or normal blood cholesterol levels. None of the study participants were taking cholesterol-lowering medications.

The analysis compared a control group with two groups assigned to consume two different quantities of nuts.

People in one of the nut groups consumed an average of 67 grams of nuts, or about 2.4 ounces, per day.

These people had an average reduction in total blood cholesterol concentration of 5.1%, and a reduction in low-density lipoprotein, or so-called LDL or "bad" cholesterol, of 7.4%.

For the people who consumed about 1.5 ounces of nuts, total cholesterol fell by 3.2%, while "bad" cholesterol fell by 4.9%—suggesting a dose-related response.

Those who consumed about one ounce daily of nuts, total cholesterol fell by 2.8% while LDL cholesterol fell by 4.2%.

Significantly, however, the drops in cholesterol weren't seen in people considered obese—a new finding.

More studies are needed to understand why nuts are less effective at lowering blood cholesterol concentration among obese people, the researchers said.

Dr. Sabaté said the biggest improvement in blood lipid levels were seen among people who started out with higher cholesterol levels, as well as among those who consumed a "Western" diet of high-fat meats, dairy products and refined grains, compared with people consuming a "Mediterranean" diet emphasizing whole grains, lots of fruits and vegetables, fish and relatively little red meat.

"For the general population consuming a Western diet, the incorporation of nuts into their daily diet will result in greater improvement of blood lipid levels than for individuals already following a healthy Mediterranean or low-fat diet," researchers wrote.

Of the 25 studies, about two-thirds of them involved almonds or walnuts. The other one-third of studies looked at either macadamia, pistachio, hazelnuts or peanuts. The studies didn't include pine nuts or Brazil nuts.

The study was funded by Loma Linda University in California and by the International Tree Nut Council Nutrition Research and Education Foundation, an international group that represents the tree nut industry.