Nuts Do Help the Heart (Just Watch Your Waist)
Scientists learned more than a decade ago that eating nuts lowers the risk of heart disease, and since then a number of studies have shown that almonds, walnuts and peanuts help lower the amount of artery-blocking LDL cholesterol in the blood. The trouble is, nuts are also high in calories--and that has kept many experts from urging Americans to eat more nuts.
But Canadian researchers decided to look at whether exchanging nuts for some other healthful snack would be worthwhile. The results came out strongly in favor of the nuts.
For three months, 27 volunteers, whose average age was 64, consumed the same amount of calories. For one month, their daily diet included a two-handful dose of almonds; another month, they ate a daily snack of a handful of almonds and half of a low-fat, whole-wheat healthy muffin; and during the third month, they had the full muffin snack every day and no nuts. The subjects had a two-week period between the months, during which they resumed their usual diets.
After one month of eating the full portion of almonds, the subjects’ LDL, or so-called bad, cholesterol decreased by 9.4% on average. One month after eating the half-dose of almonds and half a muffin, their LDL cholesterol dropped by 4.4%. There was no change in their cholesterol levels after a month of snacking on the healthy muffin and no nuts. None of the men and women gained or lost a significant amount of weight on any of the three diets.
The unsaturated fats in nuts have been given most of the credit for lowering cholesterol, but Dr. David J.A. Jenkins, director of the Clinical Nutrition and Risk Factor Modification Center at St. Michael’s Hospital in Toronto, says that the vegetable protein in almonds may also be cholesterol-lowering. (Almonds have as much protein by weight as they have fat.)
What’s not healthful, says Jenkins, the lead author, are nuts roasted in hydrogenated fats and coated with salt.
The Canadian government and the Almond Board of California funded the study.
Circulation 106: 1327-1332
Knee Surgeons Can Now Take a Backdoor Approach
Surgeons who reconstruct the knee’s posterior cruciate ligament, which helps give the knee stability, may risk injury to the major blood vessel at the back of the knee.
Traditionally, surgeons have avoided the artery by getting to the back of the knee from the front. However, that requires that the transplanted tendon make a U-turn around the back of the leg bone. Over time, the pull on the tendon causes it to stretch, and the knee often becomes less stable.
A new, more direct route--from the back of the knee--may help solve the problem. “It’s a straight shot to insert the new tendon within the thighbone,” says Dr. Mark D. Miller, co-director of sports medicine at the University of Virginia Health System. He has done about 100 reconstructions using the direct, back-to-front technique. Because the tendon doesn’t have to make that U-turn, it’s stable immediately after surgery and for years, he says.
Surgeons using the new technique learned that the artery is protected because it is pushed away from the site of the graft along with the muscle that lies next to it during the operation. After the reconstruction is complete, the muscle and artery slide back into place.
To prove that this is what happens, Miller injected barium into the knee arteries of eight cadavers on which he did PCL operations. When the area was viewed on X-rays, it was obvious that the knee artery had been moved aside by about half an inch.
Journal of Knee Surgery 15: 137-140
There’s an Exam to Detect Oral Cancer? No One Told Me
Most people know about screening for breast, colon and prostate cancer. But when it comes to oral cancer, which accounts for 3% of all malignancies, few people are aware that there’s a simple, inexpensive and painless way to detect the disease. Even worse, researchers say, most doctors and dentists don’t routinely offer the exam.
During a free three-day oral cancer screening led by the New York University College of Dentistry, interviewers asked people to complete a survey about lip and mouth cancer. They found that although 66% of the 803 participants had heard of oral cancer, only 39% had known there was an exam to detect it.
The survey revealed that 75% of those who showed up realized that tobacco is a risk factor, but only 25% were aware that frequent alcohol consumption also increased their risk. And only 25% knew that excess sun exposure was a risk factor for lip cancer. The American Cancer Society recommends an annual oral cancer exam for everyone 40 years of age and older. The exam is a simple visual examination of the tongue and lips and the mucous membranes of the mouth, with palpation of the lymph nodes of the face and neck by a physician or dentist. Although mouth and lip cancers are curable when diagnosed early, more than half are diagnosed in a late stage. That’s a shocking statistic considering that oral cancer is relatively easy to spot--85% of the cancers are visible.
Journal of the American Dental Assn. 133: 1064-107
Gene Pair Makes Some Fetuses Susceptible to Mother’s Smoking
Children exposed to cigarette smoke often have asthma and an increased sensitivity to environmental pollution. Now researchers have found in a study of nearly 3,000 children that some of them are genetically susceptible to the harmful effects of smoking even while in the womb.
USC researchers found that, among children whose mothers smoked while pregnant, those with a particular genetic pattern were more likely to have asthma and wheezing than children who didn’t have the gene variation. And the children who had been exposed in utero were nearly four times more likely to be taken to the emergency room for breathing difficulties than children who didn’t have the genes.
In the study, researchers took DNA samples from a cheek of each child and examined them for a combination of genes that normally direct the body to produce an enzyme that helps the lungs protect themselves from pollutants. Children with one particular pair of genes--known as GSTM1 null genotype--can’t produce the enzyme.
More than 45% of the children had inherited copies of that gene. When exposed in utero, they had twice the risk for wheezing with exercise. They were also twice as likely to have wheezing that was serious enough to require medication for relief as children without those genes.
The researchers also found that children who had the genotype that enabled them to produce the protective enzyme had no increased risk of respiratory problems even though their mothers smoked while pregnant. Although more research is needed to confirm these findings, the researchers say, being able to identify those at high risk of asthma could lead to helpful preventive steps. For now, Dr. Frank D. Gilliland, professor of preventive medicine at Keck School of Medicine says, “The best prevention is to have women quit smoking as part of planning a family.”
American Journal of Respiratory and Critical Care Medicine 166 (3): 457-463
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Dianne Partie Lange can be reached at DianneLange@cs.com.
