It's no secret to men that close-fitting shirt collars and tightly tied neckties are one of the most nettlesome--if trivial--inconveniences associated with being male. Now, however, researchers at the Cornell University College of Human Ecology say these dress habits may harm vision too.
In a study involving measurement of the tightness of shirt collars and ties and vision clarity in several groups of men, researchers found that neckties tied so tightly that they reduced the natural circumference of the neck measurably cut visual acuity for such tasks as reading.
The study, reported in the journal Human Factors, speculated that the relationship between necktie tightness and vision may be due to reduction in blood flow through the carotid arteries, which supply the brain and run up the neck fairly close to the skin. Researchers said 67% of men who were studied were wearing shirts or ties that were too tight. The tie was at fault far more often than the shirt collar.
An obvious preventive step: Unfasten the top button of your shirt and loosen the knot of your tie.
Dietary Fat, Cholesterol
There's no shortage of research on the effects of blood cholesterol levels on heart-disease risk in men, but for women--especially pre-menopausal women--it remains a field in which few studies have been done, and conclusions about males are presumed to hold true for females too.
It came as something of a surprise, then, that in a new project examining the relationship of fat in the diet and cholesterol in the blood of young, healthy women, a 50% reduction in dietary fat had almost no effect on cholesterol.
What this may mean is unclear, but the leader of the National Cancer Institute team that conducted the new study said the results emphasize that a great deal remains unknown about the precise relationship between fat consumed in food and levels of fatty chemicals in the bloodstream.
The researcher, D. Yvonne Jones, reported that while she continues to believe men and women alike should reduce dietary fat intake, the finding about the ineffectiveness of fat reduction in influencing cholesterol in women took her by surprise. She said this may be due more than anything to the reality that the vast majority of research studies on the subject focus on men--in whom the dietary fat-cholesterol interrelationship appears to be more clear cut.
Jones' new study was published in the American Journal of Clinical Nutrition. It focused on a total of 31 women in their late 20s whose cholesterol levels to begin with were well within healthful guidelines. The key subgroup of 15 women in whom dietary intervention was attempted had an average total cholesterol reading of 180 milligrams--well below the 200 level generally accepted as indicative of good health.
At first, the women were given diets in which 40% of total calories were fat. Then the diets were changed, cutting the fat to 20%. All of the diets included items from all the traditional food groups and were considered normal in the context of American nutrition. But the reduction in fat, the Jones team found, was accompanied only by a 12% decline in cholesterol--a change the researchers found to be insignificant.
"I really expected that there would be more of an effect of such a drastic drop in fat," Jones said in a telephone interview from Bethesda, Md. Whether women whose cholesterol levels were higher than the healthy group studied would experience the same insignificant dietary reduction is not known. But Jones said she is currently following up the study to see if women after menopause experience any change in the diet-cholesterol relationship.
German Measles at Work
The development of a German measles vaccine in 1969 brought about dramatic declines in the incidence of the disease, but outbreaks have continued--focusing new attention on the need to reach non-immunized pockets of the population. To reduce gaps in protection, moreover, a team of New York City researchers suggests a special focus on workplace immunization campaigns tailored to reach women of child-bearing age.
Employee health departments, the researchers from the New York City Department of Health said, may be in a unique position to identify working women who have not been vaccinated. The urging for greater workplace German measles (also called rubella) vaccination came after an investigation of five New York workplace outbreaks between 1983 and 1985.
If a pregnant woman gets German measles, her child may eventually suffer from a variety of serious handicaps. Vaccine protection is highly effective. In 1969, there were nearly 58,000 cases of rubella nationwide. In 1985, the figure was 604. In the first 22 weeks of 1987, there were just 170.