Wednesday, November 30, 2011

Diet Advice from Your Small Intestine

One of your digestive system’s limitations is that the body parts in charge of picking, identifying, and enjoying what you eat (your brain and your mouth) sit a great distance away from the parts that actually process and absorb your meal (mainly, your small intestine). So it’s no wonder that this system so often slips out of sync, sending you hurtling straight into dietary trouble.
The real problem is that your brain and mouth follow a somewhat outdated ingredient list. They’re always searching for the immediate gratification of sweet, calorie-dense foods. The rest of your digestive system simply processes whatever it gets. In 100,000 years of human evolution, it never occurred to anyone that people might somehow be able to consume vastly more food than they need.

The only antidote to the rampant abuses of modern eating is to simplify your diet with a few common-sense principles. And now that your small intestine has broken your breakfast down into its essential parts—protein, fat, and sugar—it’s easier to pick out these principles, and to separate what your body eats from what it needs. Here’s what your small intestine would ask for if it had a voice:

• Natural, unprocessed foods. Industrial processing—the sort of thing that changes a box of ordinary rice into a package of breakfast cereal— amounts to pre-digestion. It takes responsibility for breaking down foods away from your small intestine, and it can eliminate trace elements of hundreds of different nutrients—all for a product that tastes like flavored packing material.

• Plant-based foods, with small quantities of meat. Unless you’re a weight-training athlete, your body can get all the protein it needs from two servings of meat per day. (That’s a piece of chicken, beef, or fish that’s the size of the palm of your hand, without the fingers.) Dieticians often suggest treating meat as a condiment—in other words, as something you add to flavor a nutrient-rich plate of vegetables.

• A rich variety. Rather than obsess about the nutritional merits of squash versus sweet potatoes, strive to incorporate a range of healthy food into your diet. Highly varied dining offers another benefit: The sheer amount of healthy food tends to crowd out other, less desirable foods.

• More complex carbohydrates, less sugar. Your mouth, stomach, and small intestine eventually break down all carbohydrates into sugar. The more refined the carbohydrate, the faster the conversion, and the quicker you absorb it. This is a problem, because your digestive system is all about pacing (as demonstrated by the careful, one-squirt-ata- time food transmission from your stomach to your small intestine). Heavily refined foods leave your stomach more quickly, which reduces your body’s ability to pace itself and leads to see-sawing levels of blood sugar that your liver must work hard to adjust. But if you fill up with complex carbohydrates like vegetables, whole wheat flour, and brown rice, you’ll have a tankful of food that will fuel you with a slow, steady supply of sugar for hours to come.

• Water. If your food comes premixed with fluid, you need less saliva and gastric juice to create the creamy paste your digestive system expects. And although well-meaning nutritionists sometimes warn heavy drinkers (of water) that they can dilute their gastric acids at mealtime, the effect is minor and has little effect on the average stomach.

Source of Information : Oreilly - Your Body Missing Manual

Monday, November 28, 2011

Clearing the Smoke Marijuana remains tightly controlled, even though its compounds show promise

Preliminary clinical trials show marijuana might be useful for pain, nausea and weight loss in cancer and HIV/AIDS and for muscle spasms in multiple sclerosis. Medical marijuana studies in the U.S. are dwindling fast, however, as funding for research in California—the only state to support research on the whole cannabis plant—comes to an end this year and federal regulations on obtaining marijuana for study remain tight.

In July the Drug Enforcement Administration denied a petition, first filed in 2002 and supported by the American Medical Association, to change marijuana’s current classification. So marijuana remains in the administration’s most tightly controlled category, Schedule I, defined as drugs that “have a high potential for abuse” and “have no currently accepted medical use in treatment in the U.S.” Many medical cannabis proponents see a catch-22 in the U.S.’s marijuana control. One of the DEA’s reasons for keeping marijuana in Schedule I is that the drug does not have enough clinical trials showing its benefits. Yet the classification may limit research by making marijuana difficult for investigators to obtain.

Even as prospects for whole-plant marijuana research dim, those who study isolated compounds from marijuana— which incorporates more than 400 different types of molecules—have an easier time. The drug’s main active chemical, delta 9-tetrahydrocannabinol (THC), is already FDA-approved for nausea and weight loss in cancer and HIV/AIDS patients. The Mayo Clinic is investigating the compound, trade-named Marinol, as a treatment for irritable bowel syndrome. Researchers at Brigham and Women’s Hospital in Boston are studying Marinol for chronic pain.

Compared with smoked or vaporized marijuana, isolated cannabis compounds are more likely to reach federal approval, experts say. Pharmaceutical companies are more likely to develop individual compounds because they are easier to standardize and patent. The results should be similar to inhaled marijuana, says Mahmoud ElSohly, a marijuana chemistry researcher at the University of Mississippi, whose lab grows the nation’s only research-grade marijuana.

Other investigators say a turn away from whole-plant research would shortchange patients because the many compounds in marijuana work together to produce a better effect than any one compound alone. Inhaling plant material may also provide a faster-acting therapy than taking Marinol by mouth. While ElSohly agrees that other marijuana compounds can enhance THC, he thinks just a few chemicals should re-create most of marijuana’s benefits.

Source of Information : Scientific American Magazine

Friday, November 25, 2011

Purposefully Indigestible

Depending on your meal, your small intestine may contain quite a bit of undigested food. (This isn’t the case with the simple breakfast example because it’s short on plant matter and other sources of fiber.) In modest quantities, this undigested food benefits your digestive system and eases the passage of your meal as it scrapes through your narrow intestinal passageways. We call it fiber. One example of indigestible food is cellulose, a compound that helps form the structure of green plants.

In the dieting world, there’s a completely different class of indigestible food substances that masquerade as the sugar and fats our mouths expect, while dodging the absorption step in the small intestine. One example, sucralose (which is known commercially as Splenda), is a subtly modified version of sugar that triggers the sweet taste buds on your tongue, but can’t be broken down by the carbohydrate-processing enzymes in your body. Another example is olestra, an altered fat molecule that has the same mouth feel as fat but passes unhindered through your small intestine. (Eat olestra in great quantities, and you’ll have a significant amount of unneeded matter moving through your system, potentially leading to the abdominal cramping and loose stools mentioned in the package warning label.) These two indigestible foods are examples of food science at its creative best—and potential health concerns.

The key concern for most sugar and fat replacements is not toxic side effects, but the way they allow non-foods with no nutritional value to take up valuable stomach space. Dieters caught up in the excitement of eating without weight gain may forget that their calorie-free potato chips are displacing real foods, and in the process robbing their bodies of the vitamins, minerals, and other nutrients they need.

Source of Information : Oreilly - Your Body Missing Manual

Tuesday, November 22, 2011

Is It Safe to Drink?

The government may not be doing enough to regulate contaminants in tap water

More than 6,000 chemicals pollute U.S. drinking water, yet the U.S. Environmental Protection Agency has added only one new pollutant to its regulatory roster in the past 15 years. Environmental groups have long raised questions about this track record, and the U.S. Government Accountability Office recently joined the chorus, releasing a report that charges the agency with taking actions that have “impeded... progress in helping assure the public of safe drinking water.”

Among other things, the GAO report says, the EPA relies on flawed data. To determine the level of a particular pollutant in drinking water—which the EPA does before making a regulatory ruling on it—the agency relies on analytic testing methods so insensitive that they cannot identify the contaminants at levels expected to cause health effects. In addition, since 1996 the EPA has been required to make regulatory decisions about five new pollutants each year, ruling on those that might pose the biggest threats to public health. The GAO report asserts that the agency has been ruling only on the “low-hanging fruit”—contaminants for which regulatory decisions are easy rather than those that might be the most dangerous.

“They’re not actually doing anything to protect public health,” says Mae Wu, an attorney at the Natural Resources Defense Council. For its part, the EPA has pledged to review the nation’s drinking-water standards and to add at least 16 new contaminants to the list of those it regulates. This past February the agency reversed a longstanding decision to not regulate the rocket-fuel ingredient perchlorate, making the chemical the first new drinking-water contaminant to be regulated since 1996. In its response to the GAO, the EPA stated that “no action” was necessary to better prioritize the contaminants on which the agency will rule in the future, nor did it acknowledge the need for improvements in data collection. The agency did, however, agree to consider improving its methods for alerting the public when there are drinking- water advisories.

Source of Information : Scientific American Magazine

Wednesday, November 16, 2011

The Great Absorber

Your small intestine has two important responsibilities. First, it finishes digesting your meal, further breaking down its proteins, fats, and starches into simpler compounds. To perform this task, it gets help from several accessory organs, including your pancreas, liver, and gallbladder. Second, your small intestine absorbs your meal’s final, fully digested nutrients, pulling them out of the pasty digestive solution and passing them directly into your bloodstream, making them available to the rest of your body. The easiest way to understand what’s going on in your small intestine is to consider the different types of food it processes:
• Carbohydrates. Several hours ago, you began to digest your breakfast toast in the relatively easygoing environment of your mouth. Now, deep in your abdomen, the process continues with a new series of more powerful enzymes that shatter the remnants of your toast into simple sugars. Your body secretes these enzymes from your pancreas—a plain looking slab of an organ that squirts digestive juices into your small intestine.

• Proteins. More recently, your stomach started working on the proteins in your eggs and sausage. Your small intestine finishes the job, again with the help of enzymes from your pancreas. The end results are amino acids—fundamental building blocks your body uses to assemble hundreds of thousands of different biological compounds.

• Fats. Your body has to break these down into fatty acids. Once again, the pancreas secretes the enzymes your small intestine needs to do the job. However, before these enzymes can get to work, your body needs a way to break the big, greasy globules of fat into tiny droplets, in much the same way that dish detergent dissolves the oil from last night’s deep-fried chicken. Two organs solve the problem. First, the liver—a multifaceted organ whose main responsibility is filtering blood—creates bile that does the trick. Second, the gallbladder—a kiwi-sized organ that looks like an unremarkable green pouch—stores and concentrates this bile between meals.

Once your body breaks down these nutrients, they seep through your thin intestinal walls, along with various vitamins and minerals. To make this process easier, thin folds lined with tiny hairs cover your small intestine. These details help increase your small intestine’s surface area to promote nutrient absorption.

With the pancreas’s high-powered digestive abilities, you might wonder why it doesn’t eat itself. The trick is that the pancreas releases harmless, inactive enzymes. These enzymes switch themselves on when they meet up with the strong acids in the partly digested food in your intestine.

Source of Information : Oreilly - Your Body Missing Manual

Thursday, November 10, 2011

Using Intestines from the Animal Kingdom

Your intestines are quite important, and you’d be ill advised to part with a single foot of the stretchy tubing. However, it just so happens that the resilient tissue that lines your gut lends itself to a host of arts and crafts. Humans have capitalized on this with the help of other animals. In fact, we’re downright notorious in the animal kingdom for putting the intestines of other species to work in a variety of creative ways. Here are some examples:
• Cheese-making. Cow, sheep, and goat guts contain rennet, an important additive in the cheese-making process. Presumably, ancient man discovered this while making cheese in a convenient sack—the stomach of a dead animal.

• Music-playing. For centuries, craftsman fitted violins and other stringed instruments with tough fibers made from animal intestines. Although silk, nylon, and steel are more common today, some top-caliber musicians insist that nothing can match the sound of fresh sheep gut.

• Food. Natural sausage casings (the thin, plasticky substance that wraps your breakfast sausage) use animal gut from a pig, cow, or sheep.

• Sex. The world’s oldest known condoms (dating back to about 1640) were made from sheep intestines. They were quite expensive, which probably accounts for the roaring trade in washed, second-hand condoms that prevailed at the time.

Source of Information : Oreilly - Your Body Missing Manual

Saturday, November 5, 2011

Fasting and Detoxifying

Fasting is the age-old practice of limiting food and drink, often as part of religious festivals. Some fasts restrict all food, while others allow a stripped-down diet. Fasts may also go hand-in-hand with non-food restrictions, such as religious rules forbidding fighting, lying, and sex. (Fasts are notorious for lumping sin and pleasure together into one giant category of forbidden pastimes.)

The benefits of fasting aren’t digestive. Supporters point out how practicing selfrestraint (and enduring a little borborygmus) develops inner will. They’re less likely to point out the way fasting increases carnal pleasures post-fast. Much in the same way that you feel good when you stop striking your head against a tree, the end of a fast brings a heightened appreciation of everything you temporarily sacrificed. More controversially, fasts are sometimes studied as a way to improve health. Some studies suggest that occasional fasting or lifelong calorie restriction can boost life expectancy.

One possible reason for this phenomenon (if it actually exists) is that gentle stress may prompt the body to fire up certain beneficial repair processes. Or it may simply be that less food means less of all the ills of the modern diet—from excess sugar to runaway fat.

The score for so-called detoxifying diets is far less promising. Promoters suggest that extreme fasting, bizarre diet restrictions, or colon “cleansing” can purge toxins from your body. The idea is alluring— after all, who wouldn’t like to atone for a lifetime of dietary sin and return the body to a pristine, unpolluted state? However, the science is about as solid as a bowl of low-calorie Jell-O.

Source of Information : Oreilly - Your Body Missing Manual