In a recent issue of the American Journal of Clinical Nutrition, researchers from the Linus Pauling Institute report that reducing dietary zinc is associated with increased breakage of peripheral blood cell DNA strands, while restoring zinc to normal levels reduces breakage. The ability of zinc to increase DNA repair, in addition to its role as an antioxidant, may be responsible for its protective effect.*

For the current study, 9 men received zinc-depleted diets for 42 days. DNA strand breaks increased by an average of 57% by the end of the period, indicating that six weeks of reduced zinc intake significantly increases DNA damage in peripheral blood cells. These increases proved to be reversible by restoring adequate zinc intake.

“Overall, these data suggest that dietary zinc status affects DNA damage in peripheral blood cells and that adequate zinc status may be essential to maintain DNA integrity in humans,” the authors write.

—Dayna Dye

A report published in the International Journal of Cancer describes research conducted at Oregon State University that reveals a potential role in cancer therapy for chlorophyllin, a water-soluble derivative of chlorophyll.*

Linus Pauling Institute’s Cancer Chemoprotection Program director Rod Dashwood and his associates tested the effect of chlorophyllin on cultured human colon cancer cells. They observed that the cells spent more time in their synthesis phase, resulting in a disruption in growth that led to cell death.

The researchers discovered that chlorophyllin reduces an enzyme needed for DNA synthesis known as ribonucleotide reductase. The enzyme is also targeted by the chemotherapy drug hydroxyurea. Comparison of chlorophyllin and hydroxyurea’s effects revealed a ten times greater benefit for chlorophyllin against colon cancer cells. The finding suggests a role for chlorophyllin in combination with conventional cancer treatment, which could enable the administration of a lower dose of potentially toxic chemotherapeutic drugs.

—Dayna Dye

Researchers from the University of Toronto report in the American Journal of Epidemiology that one out of seven young adults in a sample of the population were deficient in vitamin C, which was associated with increased waist circumference, body mass index, blood pressure, and C-reactive protein (CRP), a marker of inflammation.*

Dr. Ahmed El-Sohemy and his associates examined data from 979 participants in the Toronto Nutrigenomics and Health Study conducted between 2004 and 2008. Approximately one-third of the participants had suboptimal serum vitamin C levels, and 14% had levels that were deficient at less than 11 micromoles per liter.

“The implications of these findings underscore the importance of obtaining the RDA for dietary vitamin C in order to decrease the prevalence of serum ascorbic acid deficiency in young Canadians and to potentially decrease the risk of long-term adverse health effects,” the authors write.

—Jon Finkel

In the British Journal of Surgery, researchers report the benefits of supplementing with folic acid in patients with peripheral artery disease.*

In a double-blind trial, 133 peripheral artery disease patients were assigned to receive 400 micrograms folic acid, 400 micrograms

5-methyltetrahydrofolate (5-MTHF, an active form of folate) or a placebo daily for 16 weeks.

Red blood cell and plasma folate increased in participants who received folic acid and 5-MTHF, and homocysteine was reduced compared to those in the placebo group. Brachial artery pressure index was also significantly improved in both the folic acid and 5-MTHF groups.

Due to the similarity in benefits observed in this study for 5-MTHF and folic acid, the authors conclude that the data “suggest that 5-MTHF may be a safe and effective alternative to folic acid.”

—Dayna Dye

The results of a study published online in Circulation reveal a disturbingly low percentage of Americans who meet the standard criteria for being at low risk of cardiovascular disease.*

Researchers evaluated data from four health surveys of Americans conducted between 1971-1975, 1976-1980, 1988-1994 and 1999 to 2004. Factors that conferred a low risk of cardiovascular disease included not smoking, having a total cholesterol level of less than 200 mg/dL without using cholesterol reducing drugs, blood pressure lower than 120/80 mmHg in the absence of antihypertensive medication use, having a body mass index of less than 25 kg/m2, and never having been diagnosed with diabetes.

Among the findings was that only one in twelve Americans had a low cardiovascular disease risk profile from 1994 to 2004, down from over one in ten from 1988 to 1994, a trend that the researchers attribute to an increasing number of overweight and obese men and women.

—Dayna Dye