A diet allegedly eliminates cholesterol without sacrificing red meat and dairy products; a study on how the way one eats affects digestion; links between caffeine and infertility, between soy protein and reduced stomach acid, and smoking and cholesterol levels; plus an experimental drug treatment for osteoporosis.
Recent research has made that old adage, "You are what you eat," seem to be much more than a tired cliché. Here are just a few items from the food front (as well as the latest update on Lyme disease), as reported by the editors of American Health, a magazine that stays on top of the latest in medical research, separates fad from fact and helps you preserve and improve life's most precious gift—your good health.
Can you actually lower your cholesterol level without giving up red meat, dairy foods or eggs? "Yes," says Rita Dougherty, R.D., of the USDA's Western Human Nutrition Research Center in San Francisco. Chances are that you'll lose weight, too, while getting more vitamins and minerals than ever before.
For 40 days, seven men with an average blood cholesterol of 218 and an average blood pressure of 135/85 (both higher than ideal) were allowed to eat the same number of calories as they normally did, but instead of getting between 40 and 44% of those calories from fat and downing an average of 600 mg of cholesterol a day, they got only 25% of the calories from fat and only 300 mg of cholesterol. To accomplish this, fat was trimmed from all meats, skin was removed from all fowl, margarine replaced butter, skim milk replaced whole, and vegetable oil was used instead of animal cooking fats. Since carbohydrates and proteins have less than half the calories of fat, the men ate more food to keep calories the same, but it was in the form of grains, vegetables and fruits. By the end of the study, their average blood cholesterol dropped to 185 and average blood pressure to 124/79.
A study recently completed by the National Institute of Environmental Health Sciences indicates that women who consume more than one cup of coffee daily (or its caffeine equivalent) are only half as likely to get pregnant per menstrual cycle as those who drink less. The good news is, the effects may be quickly reversed. Only caffeine consumed during the three months before the study began was found to be a factor in its results.
Dr. Allen Wilcox, the epidemiologist who headed the study, noted that genetic differences in metabolizing caffeine could also lead to differences in susceptibility: "There were women in our study who were very heavy caffeine drinkers and yet conceived right away." Other women, he says, might be adversely affected by far smaller amounts. His advice? "If a woman has been trying to get pregnant for several months, she ought to know that scientists have noted some connection between caffeine and fertility. Then she should make her own judgment."
In preliminary studies at the Veterans Administration Medical Center in Dallas, researchers have found that when healthy people eat soy protein, they produce 30 to 40% less stomach acid than when they eat the same amount of beef protein. It's too early to tell whether this effect holds true for a real world mixed meal, but the results are intriguing enough to encourage the scientists to continue their work.
When it comes to digestion, how you eat may be almost as important as what you eat. And that should concern us, because poor digestion may lead to a wide range of maladies, from ulcers to diverticulitis to colon cancer.
Dental professor and nutritionist Donald R. Morse of the Temple University School of Dentistry in Philadelphia has found that the best digestion can be achieved by coupling deep relaxation with thorough chewing, and that "eating on the run" may be even more unhealthy than was previously realized. In his studies, not only did digestion occur more rapidly during relaxation periods, but greater amounts of the sugar maltose (produced when a complex carbohydrate is broken down during chewing) were present at those times. Chewing for a full minute also increased maltose levels more than chewing for 20 seconds, but not as dramatically as did deep relaxation.
"The digestion that occurs in the mouth is a good barometer for the digestive process going on in the rest of the body," explains Morse. "After all, it all starts in the mouth, chemically and mechanically."
For the first time there's evidence that an experimental drug treatment can actually build new bone mass and halt the progress of spinal osteoporosis. Approximately 5 million Americans suffer with this form of osteoporosis, which thins the bones in the spine and causes crush fractures and stooped posture.
The new drug therapy—calcium citrate and a time-release version of sodium fluoride—was tested in a government-funded study headed by Dr. Charles Pak of the University of Texas Southwestern Medical Center in Dallas. According to Dr. Pak, the treatment restored lost bone mass at rates of up to 6% a year and reduced dramatically the tiny spinal fractures that plague those suffering from this condition.
If all goes well, he says, the slow-release drug will win the approval of the Food and Drug Administration within the next two years.
If you're a smoker, another way to lower your cholesterol level is to quit. Researchers at the American Health Foundation have found that every cigarette raises total cholesterol half a point on the average. People of all ages (excluding postmenopausal women) who smoke 30 cigarettes a day have cholesterol levels 15 to 20 points higher than nonsmokers. (Hormone shifts after menopause normally raise cholesterol levels in postmenopausal women, including nonsmokers, so researchers couldn't make firm conclusions for that group.)
Precisely how cigarette smoking alters cholesterol levels is as yet unclear, but smoking may alter levels of sex hormones that have an effect on serum cholesterol. However, if you give up tobacco, levels soon come down.
And it's not good! Borrelia burgdorferi bacteria, responsible for Lyme, are on the rise in humans and animals and are becoming an international problem. This disease, which starts out with flulike symptoms, but which can lead to arthritis, serious nerve and heart damage and even miscarriage and birth defects, is currently reported in 43 states even in some in which the white-tailed deer (and the Ixodes dammini ticks they carry) never roam. Among the animals now shown to harbor Lyme bacteria are raccoons, opossums, dogs, rabbits, horses, cattle, migrating birds and even mosquitoes and flies. (The white-footed mouse has long been implicated as a tick carrier, and at least one person in Texas and another in Wisconsin may have been infected by bites from cat-carried fleas.)
Some wildlife biologists are thought to have contracted the disease after coming in contact with the blood of slain deer that harbored Lyme bacteria, and it's possible that owners of horses or cows could become infected by inadvertent contact with the animals' urine. (One study of Wisconsin dairy farmers found that 46% had been exposed to Lyme, while a study of dogs in Suffolk County, New York, found that 65% had been exposed to Lyme bacteria—and fleas that bite infected pets can ultimately pass the organism on to people.)
In California, more than 400 people have contracted Lyme disease, apparently after having been bitten by another type of tick, Ixodes pacificus, found on birds, lizards, rodents and other mammals. Investigators say there's also evidence that both biting flies and mosquitoes are spreading Lyme disease in Europe.
What's more, you can have contracted Lyme disease without ever getting the typical bull's-eye rash, so be alert for chills, fever and other flulike symptoms. Weeks or even months after becoming infected, some people experience severe headaches, muscle pain, facial paralysis, abnormal heart rhythms and inflammation of the heart wall and surrounding sac. To know for sure if the disease is present, you need a blood test that detects an antibody to the Lyme bacterium. The test is notoriously inaccurate during the first few weeks after infection, so you might need a retest; learning the results, however, can take days. Fast, accurate assays are still in the works.
Lyme disease, if caught early, is often easily cured with antibiotics. Later on, treatment might require massive doses of intravenous antibiotics. Even then, a small number of patients don't respond to treatment, possibly because the bacteria are able to hide in nerve cells and perhaps able to enter a dormant stage.
For prevention, wear long-sleeved shirts and long pants (tucked into socks) when in wooded areas and, afterwards, check for pinpoint specks on clothes (ticks show up best on white). In a high-risk area, consider using an insect repellent that contains DEET (N, N-diethyl-meta-toluamide) on clothes and exposed areas, especially arms and hands. (Make sure it contains no more than 50% DEET for adults and 20% for children, and use it sparingly for only a day or two at a time.) Immediately remove any ticks on your skin with sharp-pointed tweezers. Grab as close to the skin as possible, and pull straight out. Treat tick bites with a topical antiseptic, and watch, for the next few weeks, for signs of Lyme. Make sure outside pets have flea and tick collars, and inspect animals after outings. Also, avoid any animal's blood, urine and feces (good advice in general), especially if you have a cut, scratch, sore or other open wound.