A high dietary intake of folate offers protection against colon cancer, particularly in cigarette smokers, report researchers affiliated with the Karolinska Institute in Sweden and the Harvard School of Public Health.* Epidemiological evidence indicates that high folate intake is associated with a reduced risk of colon cancer, but whether this effect is modified by smoking had not been previously studied.
To clarify the possible influence of cigarette smoking on folate’s protective effect against colon cancer, the study followed more than 61,000 women. Using food-frequency questionnaires, the researchers determined mean daily folate intake among the study subjects to be 183 micrograms (mcg).
During nearly 15 years of follow up, 805 cases of colorectal cancer were documented in the study group. Women who ingested less than 150 mcg of folate daily had a 39% greater risk of colon cancer compared to women who consumed at least 212 mcg of folate daily. Statistical modeling disclosed a dose-response relationship between daily folate intake and colon cancer risk, predicting that each 100-mcg increase in folate intake could decrease colon cancer risk by 34%.
Among women who had smoked cigarettes for 10 or more years, those consuming at least 193 mcg of folate daily had a 66% lower risk of colon cancer than those whose folate intake was less than 163 mcg. Although non-smokers with the lowest folate intake had a 41% lower risk of colon cancer than did smokers, smokers with the highest folate intake had the same risk of colon cancer as non-smokers with the highest folate intake.
Increasing dietary folate intake may thus decrease the risk of colon cancer. This effect is particularly notable in smokers, who experience an elevated risk for the disease.
—Linda M. Smith, RN
* Larsson SC, Giovannucci E, Wolk A. A prospective study of dietary folate intake and risk of colorectal cancer: modification by caffeine intake and cigarette smoking. Cancer Epidemiol Biomarkers Prev. 2005 Mar;14(3):740-3.
More than 350 scientists, academics, technologists, entrepreneurs, and humanists converged at Stanford University on September 16-18, 2005, for “Accelerating Change,” a conference presented by the nonprofit Acceleration Studies Foundation. Speakers discussed some of today’s most important trends in science, technology, business, and social development, with the goal of helping attendees accelerate technological change to foster professional and personal development.
John Smart, founder and president of the Acceleration Studies Foundation (www.accelerating.org), discussed some of the conference presentations with Life Extension. Featured presenters included Dr. T. Colin Campbell, author of the bestselling The China Study, which explores the findings of the China Project, the largest epidemiological study of correlations between dietary factors and health ever conducted. The China Project found that a greater consumption of a variety of high-quality, plant-based foods is associated with a reduced risk of cancer, cardiovascular disease, diabetes, and other chronic diseases that are endemic in Western nations. Dr. Campbell’s research suggests that 80-90% of all such diseases may be preventable by dietary modifications.
Dr. Greg M. Cole of UCLA discussed his recent findings regarding the potent neuroprotective effects of curcumin, the yellow pigment derived from the curry spice turmeric. Dr. Cole’s research indicates that curcumin is a potent protector against amyloid plaques. In animal studies, curcumin reduced amyloid levels and plaque burden in aging mice. Strategies that target amyloid plaque may be the key to preventing neurodegenerative conditions such as cognitive decline and Alzheimer’s disease.
Another keynote speaker was inventor and visionary Ray Kurzweil, coauthor of the recent book Fantastic Voyage: Live Long Enough to Live Forever. Kurzweil discussed his new book, The Singularity Is Near: When Humans Transcend Biology, which explores artificial intelligence, robotics, nanotechnology, and a rapidly approaching future in which humans and machines merge into a super-intelligent civilization.
By exploring innovative applications of emerging technologies across many disciplines, the presenters and attendees of the Accelerating Change conference hope to facilitate rapid, radical, and life-improving change.
—Elizabeth Wagner, ND
A higher level of dietary fiber intake in women is associated with a decreased risk of being overweight or obese, according to researchers from Tufts University.*
The investigators studied the association between various dietary components and body mass index in 4,539 adults between the ages of 20 and 59 years. Among the participants, 1,932 reported a caloric intake that was judged reasonably accurate (within a set margin of predicted energy requirements) over two 24-hour periods. Of these, only around 5% reported consuming an adequate level of dietary fiber (approximately 25 grams for a 2,000-calorie-a-day diet).
In women, a diet low in fiber (less than 12.6 grams per 2,000 calories/day) and high in fat (35% or more of total calories from fat) was associated with the greatest risk of being overweight or obese. In men, however, only the percentage of energy intake from fat was associated with body mass index.
“Weight control advice for US women should place greater emphasis on consumption of fiber,” the study authors concluded.
In addition to promoting a healthy weight, a fiber-rich diet is associated with numerous health benefits for men and women. In fact, a high-fiber diet may help reduce blood cholesterol as well as lower risk of digestive disease and heart disease. The Tufts study also illustrates that dietary fiber intake is inadequate in the US population at large. The Dietary Guidelines for Americans, published in January 2005 by the US Department of Health and Human Services, advises all adults to consume 25-30 grams of fiber daily from sources such as whole grains, nuts, cereals, fruits, and vegetables.
—Elizabeth Wagner, ND
* Howarth NC, Huang TT, Roberts SB, McCrory MA. Dietary fiber and fat are associated with excess weight in young and middle-aged US adults. J Am Diet Assoc. 2005 Sept; 105(9):1365-72.