Natural Standard Blog

Calcium Associated with Reduced Risk of Digestive Cancers

A new study suggests that calcium may help reduce the risk of digestive cancers in older adults.

Calcium is needed for muscle contraction, blood vessel constriction and relaxation, the secretion of hormones and enzymes and nervous system signaling. The recommended dietary allowance (RDA) in adults is 1,000 milligrams.

The authors analyzed data from nearly 500,000 adults aged 50-71 who participated in the National Institutes of Health (NIH)-AARP Diet and Health Study. The participants filled out questionnaires about their food and supplement intake. During the seven-year follow-up period, cancer rates were linked through state cancer registries.

By the end of the study, 36,965 men and 16,605 women developed cancer. The authors found that calcium intake was associated with a reduced risk of digestive cancers in both men and women. On average, men who consumed up to 1,300 milligrams of calcium daily had a 16 percent reduced risk and women had a 23 percent reduced risk of developing digestive cancers compared to those who consumed the least amount.

Calcium also reduced the risk of developing all types of cancer in women. However, this effect was not observed in men.

Additional research is needed to conclusively determine if calcium helps prevent cancer.

For more information about calcium, please visit Natural Standard’s Foods, Herbs & Supplements database.

Immunotherapy Studied for Peanut Allergies

In a new study, children with peanut allergies experienced improved tolerance after taking low doses of peanut allergens that were gradually increased over time.

Exposing a person to low doses of a known allergen, a technique called immunotherapy, is not a new concept. The goal of immunotherapy is to desensitize the patient so that the body builds up a tolerance to the allergen. For example, immunotherapy has been used to treat seasonal allergies and vaccine allergies.

In the study, four children with peanut allergies received low doses of peanut allergens, which increased from 5 to 800 milligrams (equal to five whole peanuts) over a six-month period. One child experienced a severe allergic reaction called anaphylaxis during the study and was treated with adrenaline.

The authors found that immunotherapy improved peanut tolerance in all participants, including the child who developed anaphylaxis. The treatment was shown to protect against at least 10 peanuts, “more than is likely to be encountered during accidental ingestion,” the authors conclude in the journal Allergy. However, in order to maintain tolerance, immunotherapy must be continued regularly.

In a related study, published in the October edition of Journal of Allergy & Clinical Immunology, children with milk allergies experienced decreased allergy symptoms after undergoing milk immunotherapy. Similar studies are being conducted in people with egg allergies.

Because food allergies can be potentially life threatening, this therapy is not recommended for general use. Until the safety of this treatment is tested in a larger population, people with allergies should avoid foods that trigger their allergies.

For more information about peanut allergies, please visit Natural Standard’s Medical Conditions database.

Soft Drinks and Kidney Disease

According to a recent cross-section study, drinking two servings of regular soda daily may increase the risk of kidney damage in women.

The authors evaluated data from the U.S. Centers for Disease Control and Prevention (CDC)'s National Health and Nutritional Examination Survey (NHANES). They analyzed the association between high intake of high fructose corn syrup in soft drinks and kidney damage in 9,358 participants who were 20 years of age or older.

The researchers found that 16.8% of the participants drank at least two sugary soft drinks daily. Women who drank two or more regular sodas daily were 1.86 times more likely to have high amounts of the protein albumin in the urine (called albuminuria), which is an indicator of early kidney disease.

However, this association was not observed in men or in overweight individuals. The authors also concluded that, "moderate consumption of one or fewer sodas does not appear to be harmful."

This study is limited by its cross sectional design. The authors also note that it is unclear if the high fructose corn syrup or excessive sugar in sodas or other factors contributed to these results. Additional research is needed before firm conclusions can be made.

For more information about kidney disease, please visit Natural Standard’s Medical Conditions database.

AHA: Omega-6 Beneficial for Heart Health

The American Heart Association (AHA) released a new science advisory recommending that at least 5-10 percent of daily calories come from omega-6 polyunsaturated fatty acids. Other groups, including the European Commission (EU) and World Health Organization (WHO), have similar guidelines.

According to the advisory, published in Circulation: Journal of the American Heart Association, human and animal trials have shown that consuming this amount of omega-6 is associated with a decreased risk of coronary artery disease.

The safety of omega-6 fatty acids has been debated, as some researchers suggested that they might actually increase the risk of heart disease. This is because a major component of omega-6 fatty acids is linoleic acid, which can be converted to arachidonic acid, a building block for some inflammation-related molecules.

William Harris, director of the Metabolism and Research Center of the University of South Dakota Sanford School of Medicine, led the AHA's two-year assessment. The authors analyzed a meta-analysis of randomized, controlled trials and more than two dozen observational, cohort, case/control and ecological studies.

The AHA committee found that in most trials, omega-6 fatty acids either did not change or lowered levels of inflammatory markers.

According to observational trials, people who consumed the most omega-6 fatty acids typically developed the fewest cases of heart disease. Other studies found that patients with heart disease generally had lower levels of omega-6 in their blood.

In controlled trials comparing the number of heart attacks in patients eating high or low levels of omega-6, those who ate more omega-6 fatty acids developed fewer cases of heart disease.

According to the AHA advisory, most Americans already eat the recommended amount of omega-6 fatty acids. Recommended daily doses range from 12 to 22 grams, depending on a person's age, gender and level of physical activity.

For more information about omega-6 fatty acids, please visit Natural Standard's Foods, Herbs & Supplements database.

Vitamin D and Cognitive Function

A new study, published in the Journal of Geriatric Psychology and Neurology, suggests that low levels of vitamin D may be linked to an increased risk of cognitive impairment in older adults.

Vitamin D helps the body absorb calcium and phosphorous. Recent research also suggests that vitamin D may help prevent osteoporosis, high blood pressure, cancer and several autoimmune diseases. Two forms are important in humans: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamins D2 and D3 are found in many dietary sources such as fish, eggs and fortified milk. The sun also helps the body produce vitamin D3. 

As people age, their ability produce vitamin D from sunlight and to convert vitamin D into its active form decreases. Therefore, older adults have an increased risk of vitamin D deficiency. 

The cross-sectional study included 1,766 adults in the Health Survey for England 2000 who were 65 years of age and older. The authors measured the participants' vitamin D blood levels and assessed their cognitive function using the Abbreviated Mental Test Score.

A total of 212 participants (about 12 percent) were considered cognitively impaired. Vitamin D levels were lower in these participants compared to those with normal cognition. In fact, about half of cognitively impaired participants had the lowest blood levels of vitamin D (8-30 nanomoles per liter of blood). According to the authors, individuals with the lowest vitamin D levels were 2.3 times more likely to develop cognitive impairment than those with the highest levels.

Early laboratory and animal studies suggest that vitamin D may have neuroprotective effects. However, human studies in this area are limited, and a potential mechanism for this effect is unclear.

This latest study is limited by its cross-section design. Additional research is warranted in this area to fully understand the potential neuroprotective effects of vitamin D.

For more information about vitamin D, please visit Natural Standard's Foods, Herbs & Supplements database.

Mercury Detected in Products Containing High-Fructose Corn Syrup

Two new studies suggest that some foods and drinks made with high-fructose corn syrup (HFCS) may contain detectable levels of mercury, a toxic metal historically used as an antimicrobial.

Mercury is a neurotoxin, and high levels of exposure can damage the brain, heart, kidneys, lungs, and immune system. Infants and young children are especially vulnerable to mercury toxicity.

In the first study, published by the Institute for Agriculture and Trade Policy (IATP), researchers collected HFCS samples from 55 products rich in HFCS.

Of the 55 products tested, 17 (or nearly 31 percent) had detectable levels of mercury. These products include:

• Quaker Oatmeal To Go Bars: 350 parts per trillion (ppt)
  
• Jack Daniel's Barbecue Sauce (Heinz): 300ppt
• Hershey's Chocolate Syrup: 257ppt
• Kraft Original Barbecue Sauce: 200ppt
• Nutri-Grain Strawberry Cereal Bars: 180ppt
• Manwich Gold Sloppy Joe: 150ppt
• Market Pantry Grape Jelly: 130ppt
• Smucker's Strawberry Jelly: 100ppt
• Pop-Tarts Frosted Blueberry: 100ppt
• Hunt's Tomato Ketchup: 87ppt
• Wish-Bone Western Sweet & Smooth Dressing: 72ppt
• Coca-Cola Classic: 62ppt
• Yoplait Strawberry Yogurt: 60ppt
• Berry Minute Maid Punch: 40ppt
• Yoo-hoo Chocolate Drink: 30ppt
• Nesquik Chocolate Milk: 30ppt
• Kemps Fat Free Chocolate Milk: 30ppt

However, the results are limited because the authors only tested one sample of each product. In addition, the type of mercury present in the samples is unknown. The lab only tested for total mercury levels, not methylmercury (typically found in seafood) or other specific types of mercury. The authors also noted that although the Environmental Protection Agency (EPA) has established a "reference dose" for methylmercury, there is currently no such standard for total mercury. Therefore, it is unclear how, if at all, these detected levels would affect human health.

Although the study does not prove that HFCS is the source of the mercury, the authors note that mercury can be used to make caustic soda. Yet, Audrae Erickson, president of the Corn Refiners Association, released a statement saying that this technology is no longer used in the United States.

In the second study, published in Environmental Health, researchers found detectable levels of mercury in nine of 20 samples of commercial HFCS. This study also did not specify the form of mercury present in the HFCS.

The Corn Refiners Association questions the relevancy of this trial. "This study appears to be based on outdated information of dubious significance," according to a public statement released by Erickson. "Our industry has used mercury-free versions of the two re-agents mentioned in the study, hydrochloric acid and caustic soda, for several years. These mercury-free re-agents perform important functions, including adjusting pH balances."

Additional studies are needed to fully understand the possible link between HFCS and mercury as well as how this contamination may affect human health.

For more information about mercury, please visit Natural Standard's Environmental Resources database.

Cutting Calories may Boost Memory

In a recent study, older adults who reduced their calorie intake by about 30 percent performed better on memory tests.

Some animal studies suggest that low-calorie diets rich in unsaturated-fatty acids, like nuts, avocados and olive oil, may be beneficial for brain function in aging rats. In this latest study, published in the Proceedings of the National Academy of Sciences, researchers aimed to determine if these same effects apply to humans.

The authors studied 50 older adults (average age: 60) whose weight ranged from healthy to overweight. The participants were divided into three groups. One group reduced their calorie intake by up to 30 percent. The second group increased their unsaturated fatty acids intake by up to 20 percent, and the third group served as the control and did not change their eating habits.

The researchers tested the participants' memory at the beginning and end of the three-month-long study. They found that verbal memory scores significantly increased an average of 20 percent by the end of the study in the reduced-calorie group. These memory improvements were also associated with decreases in insulin levels and C-reactive protein (a marker of inflammation). No significant changes in memory were reported in the other two groups.

Although these early results are promising, additional well-designed trials are needed to fully understand how a low-calorie diet may affect brain functioning.

For more information about a low-calorie diet, please visit Natural Standard's Health & Wellness database.

Webinar Forum: Obesity Integrative Care Cases (Approximately one hour)

Natural Standard Chief Editor Catherine Ulbricht, PharmD, discusses adjunct and alternative herbal treatments for the treatment and prevention of obesity. The presentation includes treatment goals, an integrative care plan and patient care cases.

Complimentary access is available until February 28, 2009. To log in, please visit www.naturalstandard.com/webinars.

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