In polite company, it may still be considered an indelicate subject. But judging from the swelling size of the laxative industry, constipation seems to be an all-too-common national ailment. In 1982, Americans spent no less than $368 million on the more than 120 preparations available over the counter.
How do these products work, when should they be used, and most important, how do you prevent the problem in the first place?
Laxatives can be grouped into four major categories: softeners and lubricants, osmotic agents, stimulants and bulking agents. A single product may contain a combination of these ingredients. When the need for a laxative is indicated, it is important to read the label carefully to see exactly what is inside.
Softeners act by facilitating the mixing of intestinal water and the fatty substances in the stool, softening the fecal matter and easing its passage through the intestine. Docosate sodium is the substance most commonly used in these preparations.
Altering Fluid Balance
Lubricants, such as mineral oil, coat the stools, making them easier to pass. Osmotic agents, which contain magnesium or sodium, alter the fluid and electrolyte balance in the colon. As a result, water is retained in the bowel, and the increased pressure stimulates intestinal movement. Magnesium may also act by stimulating the release into the gut of a hormone called cholecystokinin, which itself promotes fluid accumulation.
Stimulants such as senna, danthron, bisacodyl, phenolphthalein and castor oil are believed to work by both initiating muscle contractions in the colon and by causing increased intestinal water retention.
Finally, bulking agents derived from polysaccharides or cellulose take on water and swell in the colon, increasing stool bulk and thus encouraging intestinal muscle activity.
Unfortunately, the misconception seems to be afloat that these products are completely safe, perhaps because they are advertised widely and are available without prescription. Yet they do have side effects. Stimulants, which cause abdominal cramping, are believed to be the most abused of all laxatives. An alarming number of weight-conscious women use these products to try to purge themselves of calories after a meal.
Damage to Colon
Not only is this an ineffective antidote to overeating, but, more importantly, excessive use of stimulants can lead to fluid and electrolyte imbalances and cause serious, permanent damage to the colon. Mineral oil, when used over an extended period, may impair the absorption of the fat-soluble vitamins A, D, E and K. And whereas bulking agents are probably the safest alternative, they must be taken with adequate fluid to prevent complications.
Individuals using other medications, and particularly the elderly who may be taking several different drugs, should check with their doctor or pharmacist before taking any laxative to make sure there is no risk of undesirable interactions. Some laxatives can decrease the absorption of orally administered medications. On the other hand, some drugs and over-the-counter preparations such as anti-convulsants, calcium-containing antacids and iron supplements can lead to constipation in some individuals.
Pregnant women, many of whom suffer from constipation, should also be sure to ask the advice of their physician before choosing a laxative. Those containing stimulants are to be avoided. This is true also for nursing mothers, since these drugs will pass into the milk.
As an alternative to laxatives, which carry varying degrees of risk, three non-pharmacological, truly "all-natural" measures can both treat and help prevent constipation. In fact, they are usually the first to be prescribed by a physician.
Increase Fiber Consumption
First, increase consumption of fiber, a food component often in short supply in the American diet. Dietary fiber acts by a mechanism similar to that of the bulking agents, increasing stool volume and thereby stimulating intestinal movement. High-fiber foods include bran, whole grains, fruits, vegetables and nuts.
Second, get daily exercise. Just walking may be enough. Exercise increases the activity of the intestinal muscles, facilitating the movement of the stool through the colon. Also, get in the habit of allowing a regular time to respond to the urge to have a bowel movement. Often this is a period after a meal.
Finally, we must emphasize that whereas constipation may be a common condition and one for which treatments are readily available, it can mask far more serious medical problems. Self-treatment of constipation for more than a few days without seeking medical advice is risky business.
New Test for Trichinosis in Pork Hailed as Inexpensive and Accurate
Question: Is it true that a new test is available to detect trichinella larvae in raw pork?
Answer: Yes. It has been possible to test for trichinosis in pork for 100 years. In 1891, the United States began to inspect pork being exported because European countries claimed they would not otherwise buy it. But Europeans then enacted other protective measures to keep our pork from flooding their markets, and we discontinued the program in 1906. Not only was it extremely expensive, adding 64 cents to each pound of pork in 1894, but methods available then were not entirely effective, although they were responsible for dramatically lowering the incidence of trichinosis in Europe.
The new test, which is expected to cost only pennies per pig, has proved completely accurate. Enzyme-linked immunosorbent assay, or ELISA, is based on an antigen-antibody reaction. Trichinella antigens coat plastic wells of a test plate and trap the antibodies, which are present only in the blood of infected pigs. The reaction does not occur with pigs that do not harbor the disease. The difficulty in developing the test was to isolate the antigens secreted from the trichinella larvae, a problem finally solved by Dickson Despommier of the Columbia University School of Public Health.
The test has stood up to a variety of evaluations. It's not known just how soon our pork supply may be labeled as trichinella-free. The U.S. Department of Agriculture is testing 12,000 serum samples from slaughterhouses to get an idea of the prevalence of trichinosis.
The development of a completely effective and economical test will allow the United States to sell pork to countries that currently refuse to buy it. It is estimated that if U.S. pork is certifiably free of trichinella, the export market will increase by one-third and the domestic market by 2% during the first year, for a total return of nearly $450 million.
In addition, it is hoped that the new test may be useful for diagnosing the presence of trichinella in human serum during the early stages of the disease, when it can be treated. No such test is currently available. This same system may also prove helpful in testing for other infectious diseases of animals.
Q: Long before new studies indicated that fish might help protect against heart disease, many health experts were encouraging people to eat more of it. Are people eating more fish now than they were 20 years ago?
A: According to statistics provided by the USDA's Economic Research Service, on a percentage basis people are eating more than 20% more than they did 20 years ago. The increase sounds dramatic until we examine the actual figures. Per-capita consumption of fish has risen less than two-thirds of an ounce per week, and remains just less than four ounces, without allowances for waste. Moreover, averages tell us nothing about how many people still eat none at all.
It is interesting to note that whereas fish consumption increased by 2.1 pounds (from 10.7 pounds to 12.8 pounds) between 1963 and 1973, it rose only one-tenth of a pound more over the next 10 years, despite the fact that nutritionists and other health experts continued to support the use of more fish as part of a diet designed to limit intake of total fat and saturated fat.
Q: Since I moved to a new area, I have noticed that my tea always contains a lot of dark particles, which settle out as it sits. Also, the empty cup is lined with a dark-brown residue. Can you explain why?
A: In all likelihood you have moved to a "hard-water" region, where the water supply is alkaline and contains the minerals calcium and magnesium. The reaction occurs as the tea cools and the tannins, which are colorless, combine with these minerals to form dark-brown tannin complexes. As you may have noticed, adding lemon juice--thereby making the solution more acidic--will reverse the reaction, dissolving the particles and lightening the color.
Incidentially, it is the release of large amounts of tannins during prolonged brewing that causes the excessive astringency and puckery feeling in the mouth.