Bites

Penn State food scientists have found that mushrooms are a better natural source of the antioxidant ergothioneine than either of the two dietary sources previously believed to be best.

The researchers found that white button mushrooms, the most commonly consumed kind in the U.S., have about 12 times more of the antioxidant than wheat germ and 4 times more than chicken liver, the previous top-rated ergothioneine sources based on available data.

Numerous studies have shown that consuming fruits and vegetables which are high in antioxidants may reduce the risk of developing chronic diseases. Ergothioneine, a unique metabolite produced by fungi, has been shown to have strong antioxidant properties and to provide cellular protection within the human body.

The Penn State researchers found that among the most commonly consumed mushrooms, portabellas and criminis have the most ergothioneine, followed closely by the white buttons. A standard 3-ounce USDA serving of these mushrooms, about the amount you’d put on a cheese steak or mushroom-topped burger, supplies up to 5 milligrams.

Exotic mushrooms have even more ergothioneine. The same standard serving size of shiitake, oyster, king oyster or maitake (hen of the woods) can contain up to 13mg in a 3-ounce serving or about 40 times as much as wheat germ.

The levels of ergothioneine do not decrease when the mushrooms are cooked, according to Joy Dubost, who led the Penn State study.

Source: Penn State

Buy Direct: Mushrooms

Recipes in America’s classic cookbook, The Joy of Cooking, keep getting bigger and richer per serving, according to a new Cornell study.

By examining the 18 recipes that have been continuously published in “The Joy of Cooking” since it was first published in 1936, Cornell University marketing professor Brian Wansink has found that the average calories per serving have jumped 63 percent in the past 70 years.

The study, which is published in the Feb. 17 issue of the Annals of Internal Medicine (150:3), looks at recipes ranging from macaroni and cheese, beef stroganoff, Spanish rice and goulash to brownies, sugar cookies and apple pie.

“This jump in calories was influenced by both changes in ingredients — usually increases in fat and sugar — and changes in serving size,” said Wansink, who co-authored the study with Collin Payne of New Mexico State University-Las Cruces.

Wansink and Payne found that the average number of calories per recipe in 1936 was 2,124, about 268 calories per serving. In 2006, the average number of calories per recipe was 3,052 calories, about 436 calories a serving.

“What served four people in 1986 would have served almost seven people by 1936 standards,” Wansink noted.

In analyzing just the calorie density of the recipes — the amount of calories in the food, regardless of serving size — the foods in the 2006 edition had 37 percent more calories than the 18 recipes did in the 1936 edition.

“The Joy of Cooking,” which has sold more than 18 million copies, is one of the country’s best-known cookbooks and is considered a backbone cookbook by many home cooks. Wansink said he suspected that analyses of other long-published cookbooks would yield similar results.

“People often blame eating out as being one of the big culprits for gaining weight, but this study suggests that what we do in our own homes may be equally bad or even worse. Family size has gotten smaller, but calorie content and portion sizes have gotten bigger.”

What are considered “normal” portion sizes have gradually grown, perhaps because Americans have increasingly grown larger, the amount of income spent on food has grown proportionally smaller over the years so we can afford more food, or because we have just gotten used to the larger portions that many restaurants serve.

“To prevent overeating, I’d recommend making a recipe that says it serves four, and freezing half of it immediately for future use [assuming you are feeding four people], and only serve half of what you prepared,” said Wansink, author of Mindless Eating: Why We Eat More Than We Think. (Bantam, 2006).

Source:
Cornell University

• Bites

A new study suggests that neutralizing an acid-producing diet may be an important key to reducing bone breakdown, or “turnover,” while aging. The study comes on the heels of several other studies questioning the efficacy of consuming more-than-recommended amounts of calcium to protect against bone loss.

The study was led by physician and nutrition specialist Bess Dawson-Hughes at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Mass. ARS is the principal intramural scientific research agency in the U.S. Department of Agriculture.

Fruits and vegetables are metabolized to bicarbonate and thus are alkali-producing. But the typical American diet is rich in protein and cereal grains that are metabolized to acid, and thus are acid-producing. With aging, such diets lead to a mild but slowly increasing metabolic “acidosis.”

Researchers led by nutrition specialist Bess Dawson-Hughes at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University conducted a placebo-controlled study involving healthy male and female volunteers aged 50 or older. Key measurements were taken at the beginning and end of the intervention, which lasted three months.

A group of 78 volunteers had been provided either of two bicarbonates–potassium or sodium–along with their usual diet and exercise regimes. Key bone mineral nutrients were controlled to reduce variation in study outcomes. The bicarbonate groups consumed an amount of bicarbonate equivalent to about 9 servings of fruits and vegetables daily. This allowed the researchers to look at possible acid-neutralizing effects from an adequate, not high, alkali load.

The results showed that the volunteers in the bicarbonate groups had significant reductions in biomarkers that are associated with bone loss and fracture.

The authors concluded that increasing the alkali content of the diet, for example by consuming more fruits and vegetables, merits further study as a safe and low-cost approach to improving skeletal health in older men and women.

Source: Agricultural Research Service, USDA

• The Slow Down Diet
• Farm Produce direct from the grower

In a new study of aged laboratory animals, a diet rich in the berry and grape compound pterostilbene produced measurable improvements in brain functions and behaviors negatively affected by aging.

Animals eating a diet rich in pterostilbene performed significantly better than those in a group that did not eat the enriched diet, according to scientists with the Agricultural Research Service (ARS).

In a two-part study, published in the Journal of Agricultural and Food Chemistry, the researchers tried to determine if pterostilbene would be effective in reversing the effects of aging on mature rats.

For the first part of the study, they tested seven stilbene compounds in cell cultures and found that pterostilbene was the most effective at preventing oxidative stress. For the second part of the study, they fed aged rats one of three diets: control, or control adjusted to include either low or high concentrations of pterostilbene.

The results indicated that in aging rats, pterostilbene was effective in reversing cognitive decline and that improved working memory was linked to pterostilbene levels in the hippocampus region of the brain.

The ARS scientists noted that there are additional berry compounds showing similar potential which are also being investigated.

Source: Agricultural Research Service

• Berries
• Grapes
• Pterostilbene (Wikipedia)

Antioxidant-rich honey is a healthy alternative to commercial salad dressings that use chemical additives and refined sweeteners, according to a new University of Illinois study.

“To capitalize on the positive health effects of honey, we experimented with using honey in salad dressings,” said U of I food chemistry professor Nicki Engeseth. “We found that the antioxidants in honey protected the quality of the salad dressings for up to nine months while sweetening them naturally.”

Engeseth’s study substituted honey for EDTA, an additive used to keep the oils in salad dressings from oxidizing, and high-fructose corn syrup, used by many commercial salad-dressing producers to sweeten their salad dressing recipes.

“We chose clover and blueberry honeys for the study after an analysis of the sweetening potential, antioxidant activity, and phenolic profiles of 19 honeys with varying characteristics,” she said.

The dressings were also compared to a control dressing that contained ingredients found in current commercial salad dressings, she said.

“Salad dressings are emulsions–they contain oil and water; and to keep these ingredients together in one phase, manufacturers rely on emulsifiers and thickening agents to avoid thinning of the dressing and separation of the oil and water phase,” Engeseth explained.

When the researchers found that enzymes in the honey broke the emulsion by attacking the starch that was used to thicken the dressing, they came up with a new formulation that used xanthan gum as a thickening agent, which they then used in all the dressings.

The researchers then stored the dressings under various conditions, including 37 degrees Celsius (accelerated storage) for six weeks and 23 degrees Celsius and 4 degrees Celsius for one year, followed by an evaluation of their oxidative stability.

After nine months of storage, both types of honey were as effective as EDTA in protecting against oxidation or spoilage. Blueberry honey performed slightly better than clover.

Engeseth said that many consumers prefer products with natural ingredients and that salad dressings made with honey should appeal to these consumers.

“There’s such a wide range of salad dressings on the market–some unique salad dressings as well as inexpensive products that perform beautifully. If manufacturers are interested in developing salad dressings that have a healthy twist, we’ve demonstrated that using honey as both an antioxidant and a sweetener is one way to do this,” she said.

Sources:
Journal of Agricultural and Food Chemistry
University of Illinois College of Agricultural, Consumer and Environmental Sciences

• Honey
• Dressings, Oils & Marinades

Drinking hibiscus tea lowered blood pressure in pre-hypertensive and mildly hypertensive adults in a clinical trial at the Antioxidants Research Laboratory of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, Mass.

The clinical trial tested 65 volunteers, aged 30 to 70 years, whose systolic blood pressure was 120 to 150 mm Hg and whose diastolic blood pressure was 95 mm Hg or less at the start of the study. Blood pressure readings of 120 over 80 or greater are considered a risk factor for heart disease, stroke and kidney disease.

For six weeks, about half the group was randomly selected to drink three cups of hibiscus tea daily. The others drank a placebo beverage containing artificial hibiscus flavoring and color. All participants were advised to follow their usual diet and maintain their normal level of activity. Before the start of the study, blood pressure was measured twice, one week apart, and at weekly intervals thereafter.

The findings show that the volunteers who drank hibiscus tea had a 7.2 point drop in their systolic blood pressure, compared to a 1.3 point drop in the volunteers who drank the placebo beverage.

The data supports the idea that drinking hibiscus tea may play a role in controlling blood pressure

Source: Agricultural Research Service, USDA

• Tea direct from the blender

Giving children with milk allergies increasingly higher doses of milk over time may ease, and even help them completely overcome, their allergic reactions, according to the results of a study led by the Johns Hopkins Children’s Center and conducted jointly with Duke University.

Despite the small number of patients in the trial — 19 — the findings are illuminating and encouraging, investigators say, because this is the first-ever double-blinded and placebo-controlled study of milk immunotherapy. In the study, the researchers compared a group of children receiving milk powder to a group of children receiving placebo identical in appearance and taste to real milk powder. Neither the patients nor the investigators knew which child received which powder, a rigorous research setup that minimizes the chance for error and bias.

The findings of the study are reported in the Journal of Allergy & Clinical Immunology

“Our findings suggest that oral immunotherapy gradually retrains the immune system to completely disregard or to better tolerate the allergens in milk that previously caused allergic reactions,” says Robert Wood, M.D., senior investigator on the study and director of Allergy and Immunology at the Johns Hopkins Children’s Cebter. “Albeit preliminary and requiring further study, these results suggest that oral immunotherapy may be the closest thing yet to a ‘true’ treatment for food allergy.”

Currently, food allergy management involves complete avoidance of the trigger foods, waiting for the child to outgrow the allergy or treating allergic reactions if and when they occur. The latter could be dangerous, investigators say, because these common foods are difficult to avoid and some reactions can be severe and even life-threatening.

The Centers for Disease Control and Prevention estimates that food allergies are on the rise with 3 million children in the United States now having at least one food allergy, an 18 percent jump from 10 years ago. Milk allergy is the most prevalent type of food allergy.

“Given that the quality of life of a child with a food allergy is comparable to the quality of life of a child with diabetes, we urgently need therapies that go beyond strict food avoidance or waiting for the child to outgrow the allergy,” Wood says.

Researchers followed allergic reactions over four months among 19 children with severe and persistent milk allergy, 6 to 17 years of age. Of the 19 patients, 12 received progressively higher doses of milk protein, and seven received placebo. At the beginning of the study, the children were able to tolerate on average only 40 mg (.04 ounces or a quarter of a teaspoon) of milk.

At the end of the four-month study, both groups were given milk powder as a “challenge” to see what dose would cause reaction after the treatment. The children who had been receiving increasingly higher doses of milk protein over a few months were able to tolerate a median dose of 5,140 mg (over 5 ounces) of milk without having any allergic reaction or with mild symptoms, such as mouth itching and minor abdominal discomfort. Those who had been getting the placebo remained unable to tolerate doses higher than the 40 mg of milk powder without having an allergic reaction. In the group receiving milk protein, the lowest tolerance dose was 2,540 mg (2.5 ounces) and the highest was 8,140 mg (8 ounces). Lab tests showed the children who regularly drank or ate milk had more antibodies to milk in their blood, yet were able to better tolerate milk than those who took the placebo.

The researchers caution that it remains unclear whether the children would maintain their tolerance once they stop consuming milk regularly. “It may very well be that this tolerance is lost once the immune system is no longer exposed to the allergen daily,” Wood says, emphasizing the findings require further research and advises parents and caregivers not to try oral immunotherapy without medical supervision.

A powerful antioxidant in green tea may prevent or delay the onset of type 1 diabetes, according to Medical College of Georgia researchers.

The discovery was made during tests of EGCG, green tea’s predominant antioxidant, in a laboratory mouse with type 1 diabetes and primary Sjogren’s syndrome, which damages moisture-producing glands, causing dry mouth and eyes.

“Our study focused on Sjogren’s syndrome, so learning that EGCG also can prevent and delay insulin-dependent type 1 diabetes was a big surprise,” said Dr. Stephen Hsu, molecular/cell biologist in the School of Dentistry.

They found it also worked well in their original disease focus.

In the mouse, EGCG reduced the severity and delayed onset of salivary gland damage associated with Sjogren’s syndrome, which has no known cure.

“EGCG modulates several important genes, so it suppresses the abnormality at the molecular level in the salivary gland. It also significantly lowered the serum autoantibodies, reducing the severity of Sjogren’s syndrome-like symptoms,” Dr. Hsu says. Autoantibodies are antibodies the body makes against itself.

Both type 1 diabetes and Sjogren’s syndrome are autoimmune diseases, which cause the body to attack itself. Autoimmune disorders are the third most common group of diseases in the United States and affect about 8 percent of the population, says Dr. Hsu. Sjogren’s syndrome can occur alone or secondary to another autoimmune disease, such as lupus, rheumatoid arthritis or type 1 diabetes.

The study, published in the Oct. 24 issue of Life Sciences, supports earlier research showing EGCG’s impact on helping prevent autoimmune disease.

“The benefit of using green tea in preventing or slowing these autoimmune diseases is that it’s natural and not known to harm the body,” says Dr. Gillespie, periodontics chief resident at Fort Gordon’s Tingay Dental Clinic. “EGCG doesn’t have the negative side-effects that can be associated with steroids or other medications that could otherwise be prescribed.”

Source: Medical College of Georgia

• Tea
• More Bites