Diet experts urge move to poultry, fish and beans after results of long-term study.



Possible culprits in meat include iron, toxins formed during cooking and preservatives.
A diet packed with burgers, sausage and steak boosts the risk of developing colon or rectal cancer, a study confirms, lending weight to nutritionists' call for a switch to healthier alternatives.

A plethora of previous reports have connected red meat and colorectal cancer, which is the third most common cause of cancer-related deaths in the United States. But some of the results are inconsistent, and few studies have examined participants' diet over long periods, during which eating habits can change.

The new study is one of the most comprehensive so far. Michael Thun of the American Cancer Society (ACS) in Atlanta, Georgia, and his team collected information on the meat-eating behaviour of nearly 150,000 people in the United States in 1982 and in 1992. They divided them into three groups according to the amount of meat they ate, and noted which patients had developed colorectal cancers by 2001.

The group that ate the most processed meat had twice the risk of developing colon cancer compared with those who ate the least, the team found; and those who ate most red meat had a 40% higher risk of getting rectal cancer.

By contrast, those who ate the highest quantity of poultry or fish had a 20-30% lower risk of developing the diseases, the team reports in the Journal of the American Medical Association1. This applied even when the researchers took into account other risk factors, such as being overweight, not taking exercise and not eating fruit and vegetables.

“Substituting pistachio-encrusted salmon for roast beef is not a culinary sacrifice.”
Meaty study

The case against red meat still needs back-up from other studies. But for now, people would be well advised to cut back their consumption of red and processed meat, says Marjorie McCullough, an author of the paper, also at the ACS. This might involve removing red meat from a few meals per week, she suggests, or choosing smaller portions.

Members of the high risk group ate around 55-85 grams of red or processed meat each day, roughly equivalent to a medium sized burger. Red meat includes burgers, meatloaf, beef, liver and pork. Processed meat includes bacon, sausage, hot dogs, ham, salami and lunch meat.

Researchers are not yet clear which ingredient of meat might trigger cancer. Possible culprits include iron, toxins formed during cooking or the nitrates and nitrites used to preserve processed meats.

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Replacing red meat with some combination of fish, poultry, nuts and beans will probably help cut your risk of colorectal cancer, says nutritional expert Walter Willett of the Harvard School of Public Health in Boston. "It will have some beneficial effects for reducing heart disease as well," he adds.

"Fortunately, substituting pistachio-encrusted salmon and gingered brown basmati pilaf for roast beef with mashed potatoes and gravy is not a culinary sacrifice," Willett writes in an editorial that accompanies the study.

Benefiting from kind assistance of a group of top specialists of the country in organic medicines, Sepid Teb Nia Pharmaceutical Research and Development Company has celebrated honorable commencement of its activity in Sept of this year. In the said eve, Dr Seyed Jafar Mir Fakhraee, Secretary of Syndicates for Manufacturers of Herbal Medicines stated that accomplishment of various projects in the country in the areas of pharmaceutical engineering, molecular biology and formulation promises ever-increasing promotion of scientific level and realization of divine goals of health in the society and the most significant reliance of practitioners in the said area is to obtain the most important and effective achievements in the said industry. Moreover, Ms Dr Pour Shaghaghi, Managing Director of Sepid Teb Nia Company stated on scientific characteristics of the said center and further added: Thanks to valuable knowledge and scientific learning of its colleagues, Sepid Teb Nia Company has the capability to exchange technologies for producing herbal medicines and supplements at global quality standard levels through active and well-known producers all over the world (especially European producers) to our beloved homeland, Iran, the said Company may act upon development of new formulations, innovation in taking the best advantages of fresh compounds and materials, and eventually producing distinguished products in the Middle East.
Moreover, Dr Seyed Hossein Etemadi, the founder of Yaghout Rooyan Corporation, stated that he was grateful with accomplishment of the aforesaid project. He further added that being pioneer in presenting essential approaches with respect to public health promotion shall be an honor for this Company because we all do believe that the most significant concern of each Iranian individual is to serve his beloved homeland and to Iranians. He pointed out that materialization of research projects in the said field, modification of pharmaceutical problems of people of different classes, optimization of safety-pharmaceutical standards in the nation and reengineering of production procedures in the said area all designate growingly jump of the said industry. In conclusion, he stated his hopefulness for registration of new medicines, manufactured by the said Company in near future with scientific circles and distribution of the same in global production markets accordingly. He also pleaded with Almighty God for ever-increasing success of health practitioners across the nation.

With previous evidence suggesting that melatonin may have a role in glucose metabolism, researchers have found an independent association between decreased secretion of melatonin and an increased risk for the development of type 2 diabetes, according to a study in the April 3 issue of JAMA.

"Melatonin receptors have been found throughout the body in many tissues including pancreatic islet cells, reflecting the widespread effects of melatonin on physiological functions such as energy metabolism and the regulation of body weight," according to background information in the article. "Loss-of-function mutations in the melatonin receptor are associated with insulin resistance and type 2 diabetes. Additionally, in a cross-sectional analysis of persons without diabetes, lower nocturnal melatonin secretion was associated with increased insulin resistance." A prospective association between melatonin secretion and type 2 diabetes has not been previously reported.

Ciaran J. McMullan, M.D., of Brigham and Women's Hospital, Boston, and colleagues conducted a study to investigate the association of melatonin secretion and the incidence of type 2 diabetes. The analysis consisted of a case-control study nested within the Nurses' Health Study cohort. Among participants without diabetes who provided urine and blood samples at baseline in 2000, the researchers identified 370 women who developed type 2 diabetes from 2000-2012 and matched 370 controls. Statistical analyses for determining associations between melatonin secretion at baseline and incidence of type 2 diabetes included controlling for demographic characteristics, lifestyle habits, measures of sleep quality, and biomarkers of inflammation and endothelial dysfunction.
retion of melatonin varied widely among participants in the study; the median (midpoint) urinary ratio of 6-sulfatoxymelatonin to creatinine was 67.0 ng/mg in the highest category compared with 14.4 ng/mg in the lowest category. The median ratio was significantly higher among controls (36.3 ng/mg) than among cases (28.2 ng/mg). Insulin sensitivity was higher among women with higher urinary ratios of 6-sulfatoxymelatonin to creatinine.

The researchers found that after controlling for body mass index and other lifestyle factors, menopausal status, family history of diabetes, history of hypertension, use of beta-blockers or non-steroidal anti-inflammatory drugs, region of the United States, and plasma biomarkers of diabetes risk, participants in the lowest category of urinary ratio of 6-sulfatoxymelatonin to creatinine had a 2.2 times higher odds of developing type 2 diabetes compared to participants in the highest category.

Women in the lowest category of melatonin secretion had an estimated diabetes incidence rate that was more than double that of women in the highest category (as measured by cases per 1,000 person-years).

"It is interesting to postulate from these data, in combination with prior literature, whether there is a causal role for reduced melatonin secretion in diabetes risk. Further studies are needed to determine whether increasing melatonin levels (endogenously via prolonged nighttime dark exposure or exogenously via supplementation) can increase insulin sensitivity and decrease the incidence of type 2 diabetes," the authors conclude.