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Figure 3.5 Stop Sign Food entering the small bowel stimulates release of the substance CCK into the wall of the stomach. That’s where the vagus nerve senses that we’re full and informs the satiety center in our brains to tell our hand to put down the buttered popcorn.

FACTOID

While the majority of taste buds are located on your tongue, you also have taste buds on the roof of your mouth.

Without having to go through the chemical pathways of your body (your bloodstream), CCK acts as a very direct message and indicator of your fullness. (Remember, leptin is more of a long-term indicator of your satiety; CCK provides a very short-term, intense message.)

After the food spends some time in your stomach, it will slowly leave that reservoir and go into the small intestine via the duodenum, the first part of your intestines that comes right after the stomach. That’s when CCK puts up a digestive detour sign, in a very clear physical signal that makes you feel full. It causes the pylorus—the opening at the end of the stomach—to slam shut; that keeps food from moving into the small bowel. That’s how your stomach gets full physically and how you feel full mentally. One interesting note: High-saturated-fat diets lead to less CCK sensitivity, so you do not feel as full as you should after eating a steak.

After the stomach, your food enters the small intestine and has a head-on collision with bile. Bile is the thick green digestive fluid that’s secreted by the liver, stored in the gallbladder, and released into the small intestine. (CCK also has a third effect: It’s what causes the gallbladder to contract.) After fat is broken down into smaller particles by substances called lipases, which are released by the pancreas, these tiny particles interact with bile to form a compound that is easily absorbed by the cells of your body. Bile surrounds the fat in our meal like soap surrounds grease on our hands so it can be scrubbed from the intestinal wall and better digested and absorbed.

Once it reaches the bloodstream, food continues to influence how hungry you may feel. Elevated blood sugar sends your brain the message that it’s time to take your plate to the sink and hit the couch. When your blood sugar is low, that’s what stimulates hunger and causes you to feed like a rat in the Kraft aisle.

Many of us get into trouble when we eat foods with simple sugars (think soft drinks, jelly, cake). Simple sugars create a rebounding effect. You’re feeling blah, so you eat a 3 Musketeers. That sugar surge works like an electrical jolt, and you instantly feel more energy. But less than two hours later, that energy surge (in the form of elevated blood sugar levels) plummets, and then you feel blah again. Your conclusion? You must need another Musketeer. That rebound effect (combined with the desire for the taste that’s stimulated by the pleasure center in your brain) can put your body in biological turmoil, where you eat to feel better, though what you’re eating is actually making you feel sluggish, so you swirl and swirl around, always feeling like you need to eat.

The Word on GERD

Fat doesn’t just pose problems for your belly and subway turnstiles; it also can mess with your throat. About half of obese people have the chest-burning condition called GERD (gastroesophageal reflux disease). The thinking is that extra fat in the belly pushes down on your stomach, thereby opening the angle of the GE junction and pushing it toward the chest. (Remember, it’s at an acute angle to keep food from going back up your throat every time you eat.) The pried-open angle makes it easier for acid and food to be pushed back up. Plus, the extra fat in the belly puts pressure on the contents of your bowel. More pressure, more GERD. What’s the big deal? Besides the unpleasant sensation of tasting your food on the way up, GERD also burns your esophagus-in the same way that the sun burns your skin. After a burn, it takes a couple days to heal, but if the burning happens over and over, it means you’re burning the tissues and are more likely to develop cancer there, just like repeated sunburns increase your risk of skin cancer. Taking half a full aspirin or two baby aspirin (you want 162 mg) with a glass of water decreases this risk by about 35 percent. By the way, alcohol, coffee, pepper, acidic foods like tomatoes and OJ, and, to a lesser degree, chocolate increase GERD symptoms. The best way to manage symptoms until you lose weight is to avoid meals within three hours of bedtime and to put blocks under the head posts of your bed so that you sleep at a slight tilt. (Pillows usually don’t work, since your head will typically roll off the pillow.)

YOU-reka! At the bottom end of your small intestine (before it joins your large intestine), food hits the ileal brake—another signal that you’re full. At this juncture there’s a traffic signal that slows the passage of the slurry of intestinal contents from the small intestine to the large intestine. It’s called the ileocecal valve. The squeezing required to overcome this traffic signal valve is reduced naturally by some foods, since your body feels that you’re still digesting and not ready to evacuate those foods yet. Very little absorption of nutrients occurs in the colon, so once the food passes the ileocecal valve, not much more happens except that you reabsorb water while consolidating the waste you’ve formed. The result: You have a traffic backup in your gut, and if you try to send more cars down the road, the problem’s only going to turn into a fuller feeling. It’s one of the reasons why fiber kills cravings, because fiber slows down the transit of food from your small intestine to your large intestine, keeping that full feeling. In the next chapter, we’ll pick up the rest of the digestive journey in the intestines, where some of the key fat-storing processes take place.

Figure 3.6 Acid Trip Fat presses on the gastroesophageal junction and unkinks this connection, which makes acid and reflux move up toward the throat. Pressure on the stomach from intra-abdominal fat increases the backwash.

The System of Satisfaction

Though it may seem that we have endless reasons to eat-to celebrate holidays, to beat stress, to pass time between Super Bowl commercials-there’s only one real reason why we need food: for energy. That energy allows our organs to function, our muscles to move, and our bodies to keep warm. And to a large extent our brains help control how we convert food to energy. To help understand the process that your body goes through to use energy, we’ll break down the metabolic path into two phases.

 Digestive Phase: Your hypothalamus orchestrates this phase of metabolism by receiving signals from throughout your body about whether you’re hungry or not so that your body can use energy to power itself. Here’s how: Your body has a short-term reservoir for energy in the form of glycogen, a carbohydrate primarily stored in your liver and muscles. After eating, when you have glucose (sugar) and insulin (the hormone produced in the pancreas to transport glucose), your body uses all of the glucose it needs for immediate fuel but takes the rest and stores it as glycogen. If your blood glucose level falls, your pancreas stops releasing insulin-and then releases another G substance, glucagon, which converts the stored energy (glycogen) to sugar (glucose). So the effect is that when your intestinal gas tank empties of sugar (in other words, when our ancestors were fasting between bison hunts), your body is still able to supply crucial energy to your central nervous system by converting glycogen to glucose.

 Fasting Phase: When you’re sleeping or go long periods without eating, your body needs to have a supply of energy to keep your organs functioning. Once you use up all of your available glucose during the digestive phase of metabolism (your body stores only about 300 calories in the short-term glycogen reservoir), it taps a long-term reservoir: fatty tissue in the form of triglycerides (molecules that include a carbohydrate-containing glycerol). This keeps you going until you break the fast with breakfast.

Figure 3.7 First-degree Burning Feasting allows our livers to store excess sugar as glycogen, so we can access energy without eating for hours. Once glycogen stores are full we save the excess energy from an ice cream sundae as fat. To break down fat we first have to use up glycogen, which can take a half hour of exercise. That’s when the body automatically begins burning up fat.

YOU TIPS!

Slow the Process. Especially before your meal. If you have a little of the right kinds of fat just before you eat you can trick your hormonal system by sending the signal to your brain that you’re full. If you eat a little fat twenty minutes before your meal (70 calories or so of fat in the form of six walnuts, twelve almonds, or twenty peanuts), you’ll stimulate production of CCK, which will both communicate with your brain and slow your stomach from emptying to keep you feeling full. (CCK release and ghrelin reduction take about twenty minutes to kick in and take about 65 calories of fat to stimulate.) That way, you’ll be able to sit down for a meal and eat for pleasure, not for hunger-which is one way to ensure you’ll eat less. The average person is finished eating well before his satiety signals kick in, thus counteracting any possibility that his hormones can help him. For the same reason, you should eat slowly. If you down your food faster than a MiniVac, you won’t allow your satiety hormones time to kick in.

Set the Early Fiber Alarm. Many of us may associate fiber with better health and increased toilet time, but fiber is the speed bump of your GI interstate. It slows everything way down. Technically, it works by slowing the transit of food across the ileocecal valve, keeping your stomach fuller for longer. The result: a greater feeling of satiety and an increase of appetite-suppressing CCK-like signals. While you should aim for around 30 grams of fiber a day, the key is bulking up in the morning. Studies show that consuming fiber in the morning (at breakfast) makes you less hungry in late afternoon-a notorious candy-sucking, diet-busting time of day. Great sources of breakfast fiber include oatmeal, cereal, whole grains, and fruit. (You’ll note that every breakfast in the YOU Diet-see Part 4-has a lot of fiber in it, whether it’s the cereal or the vegetables in an egg white omelet or the whole wheat bread. And morning snacks, like an apple, also have fiber.)

Besides controlling blood sugar levels and decreasing insulin levels, fiber also reduces calorie intake for up to eighteen hours a day. Start with 1 to 2 grams of dietary fiber before meals and at bedtime and slowly increase to 5 grams. (If you add it all at once, you’ll produce more gas than a Saudi oil field.) The supplement konjac root also seems to have a fiber-related effect. One study showed a nearly six-pound weight loss in eight weeks for those who ate 1 gram of it an hour before their meals.

Step Down to the Plate. Monstrous portion sizes are one of our stomach’s biggest enemies: Studies show that when you’re served bad foods in large containers, you’ll eat up to one-third more than if you were served in smaller containers. By getting served in larger popcorn boxes, bigger dishes, and taller cups, we’ve automatically been tricked into thinking that availability should dictate how much we eat rather than physical hunger. You don’t have to go through drastic changes to make small ones. For starters, change your serving plates to the nine-inch variety to give yourself the visual and psychological clue that you’re full when your physical appetite has been sated. That’s important because studies show visual clues help determine how full you are, in that you may not feel satisfied until your plate is clean, no matter how large the plate is. That’s also reason never to eat directly out of a box or carton and always to remember that one serving size of a food is often about the size of a fist.

Slow Down. Stomach growling stimulates appetite, but growling doesn’t really tell you how hungry you are. It tells you to eat but not how much to eat. That’s why meal size is so important. You’re hardwired to eat but you’re not hardwired to eat a lot. Having a big meal quickly won’t stop you from wanting to eat a few hours later. So slow down and let your CCK act; it takes about twenty minutes after the nuts to decrease your desire to eat.

Add Pepper. Red pepper, when eaten early in the day, decreases food intake later in the day. Some credit the ingredient capsaicin for being the catalyst for decreasing overall calorie intake and for increasing metabolism. It also appears to work by inhibiting sensory information from the intestines from reaching the brain, which is particularly effective in reducing appetite in low-fat diets. Capsaicin works by killing—or at least stunning-the messages that you’re hungry. So add red peppers to your egg-white omelet.

YOU Test

Are You a Supertaster?

We all know that foods we like may send others seeking gas masks. But your tongue-related genetics may play an even bigger role in waist management. It could mean that you’re either not getting the right foods, or more prone to downing an after-dinner pie before the check arrives.

If you’re classified as a “supertaster,” you tend not to eat fruits and vegetables because they may taste very bitter, thereby putting yourself at a higher risk of certain diseases and colon polyps because you’re not getting the nutrients from fruits and vegetables. You should supplement your diet with a multivitamin to ensure you’re getting the right nutrients, as well as use fruits and veggies to enliven other things-as in salads and desserts and as moisturizers on breads (tomato sauce works great here). And if you’re an “undertaster,” you may be more prone to eating (and overeating) sweets because it takes more of a taste to satiate you. By the way, researchers say about 25 percent of us are supertasters and 25 percent are undertasters, while the rest of us are regular tasters.

Which taster are you?

 The Saccharin Test: Mix one pack of saccharin (Sweet’N Low) into two-thirds of a cup of water; that’s about the size of the tennis ball. Now taste the water. You’ll probably taste a mix of both bitter and sweet, but see which taste is stronger. If sweet is dominant, then it means you’re probably an undertaster, and if bitter is dominant, it means you’re probably a supertaster. If it’s a tie, you are like half the population, so don’t sweat it. To be sure, you may have to do the test more than once to tease out differences.

 The Blue Tongue Test: Wipe a swab of blue food dye on your tongue and see the small circles of pink-colored tissue that polka-dot the newly painted blue canvas. Those are your papillae. Then put a piece of paper-with a 4-millimeter hole, or the size of a hole punch in three-ring paper-over your tongue. Using a magnifying glass, count the little pink dots you see in the hole. If you have fewer then five dots, it means you’re an undertaster, while more than thirty indicate you’re probably a supertaster.

Chapter 4
Gut Check
The Dangerous Battles of Inflammation in Your Belly

Diet Myths

 Your stomach is the place where you store your belly fat.

 Diets are mostly about calorie control.

 Your brain is the only part of your body that reacts emotionally to food.

We all know about the daily skirmishes that play out in the battle against obesity. You versus the ranch dressing, you versus the dessert tray, and in the title fight, your butt versus your college jeans. But it would be a mistake to think that every weight-loss war happens at the table or in the privacy of your own closet. In fact, millions of little firefights break out inside your gut every time you eat or drink—and these are the most influential battles in your personal crusade against excess weight. Deep inside your éclair-encrusted gut, you have cells and chemicals that react and respond to food in two ways: as an ally or as an enemy.

As we move along in our digestive journey to the second half of our digestive system, we’ll explore these battles and how they influence your waistline. Here, your body doesn’t just form allies or fight enemies according to how many calories a particular food has, or how greasy it is, or whether its mascot is a red-haired clown. When interrogating nutrients as they pass through your digestive system, your body classifies them by what kind of inflammatory effect they have; the enemies contribute to inflammation, and the allies quiet it.

We’re not just talking about the inflammation that happens when your belly balloons to the size of a convention center, or the inflammation that happens to your joints if you have arthritis. We’re talking about the chemical reaction of inflammation that happens within your bloodstream and is an underlying cause of weight gain. This process is like the rusting of our bodies. Just like metal rusts when exposed to oxygen, inflammation is caused when oxygen free radicals (no political affiliation) attack innocent bystanders in our bodies.

Inflammation happens on many different levels and through several different mechanisms, many of them having to do with food. Not only can you get inflammation through allergies to food, but you can also get inflammation in the rest of your body—through the way your liver responds to saturated and trans fats, and through the way your body and belly fat respond to such toxins as cigarettes and stress. In turn, these inflammatory responses can cause things like hypertension, high cholesterol, and insulin resistance—and those inflammatory responses influence the total-body mother of all inflammation in your arteries, which leads to heart disease. (We’ll discuss these at length in the next chapter.)

How Tolerant Are You?

With more than 100 million neurons in your intestines, gastrointestinal (GI) pain is immediate, but the level of GI discomfort you feel depends on your genetics; specifically on your tolerance of or allergies to certain foods and your genetic disposition for feeling the effects of those GI land mines. While there are certainly pharmaceutical solutions for dealing with the digestive explosions, there are also foods that produce an anti-inflammatory effect and can come in and put out the fire (see YOU Tips). During these inflammatory firefights, your intestines are contracting too much, or are being dilated-a painful process that works through the vagus nerve. Too much stimulation or distension of the bowel is what causes the pain. Some of us are less sensitive to those internal motions, so we may not always be getting the clue from our gut. These are some of the more common GI firestorms involving food intolerance:

 Enzyme deficiencies: When your intestines lack enzymes to metabolize specific foods like milk or grains or beans, the food remains undigested, so you start feeding your intestines’ ravenous bacteria. The result: lots of intestinal dilation and more gas than a Hummer fuel tank. The most common of these is lactose intolerance (the lack of GI agreement with dairy products), and a close second is an allergy to the protein gluten from wheat (and rye and barley; nutritional good guys). As an example, when you lack the enzyme lactase, the sugar lactose in the milk reaching your intestine is not metabolized, so it’s presented to your intestinal bacteria, which metabolize the lactose in your intestines, producing a lot of gas.

 General GI disorders: Problems like irritable bowel syndrome, which causes gut-related symptoms like diarrhea and abdominal pain, are caused by sensitive nerves and result in inflammation in the intestinal walls. For example, we usually all pass the same amount of gas a day (about fourteen times, or 1 liter total), but some of us sense discomfort from that gas more than others do.

 Psychological responses: Food aversions can develop if, say, a person had a bad vomit-inducing shrimp dinner one night. The response would be to associate the shrimp dinner with the painful aftereffects and avoid it.

Of course, there are a number of extreme-end GI problems like infections, parasites (worms are the world’s most successful weight-loss technique-but we don’t recommend the Fear Factor diet), and violent and even lethal allergic reactions to food. The point is that we all may have degrees of intolerance in ways we may not even recognize. And we need to start listening to what our small intestine is trying to tell us about what we eat. Once you recognize that the general sense of “feeling off” can be caused by the foods you eat you can identify—and work to eliminate, reduce, or substitute-the substance that makes your gut twist like an animal balloon.

FACTOID

For those of you who’ve stayed up wondering, here’s the reason why your gas may smell and other people’s gas may not: Think of your body as a refrigerator. If you let food sit in there, it’s going to smell after a while. In your body, sulfur-rich foods like eggs, meat, beer, beans, and cauliflower are decomposed by bacteria to release hydrogen sulfide-a smell strong enough to flatten a bear. Avoiding these foods is the ideal solution, but when stinky gas persists, the best solutions are leafy green vegetables and probiotics (specifically lactobacilli GG or Bifidus Regularis), which work like baking soda in your fridge to reduce odor. Beano can sometimes work with beans, but soaking the beans ahead of time is useful as well.

Here, we’ll look at how inflammation happens at the gut level, and then, in the next chapter, how that can lead to inflammation at the total-body level.

Inflamed Gut: The Intestinal Firefights

At the intestinal level, foods can cause inflammation of your intestinal wall through such things as allergies, bacteria, or other toxins. When food incites inflammatory responses in your gut, it’s as if a grenade has been launched throughout your digestive system (see Figure 4.1 on page 81). Then in response to this already damaging grenade, your body tosses more grenades to create an apocalyptic digestive War of the Worlds. The effect is that the more inflammation we have in our intestines, the more toxins can enter our bloodstream.

During this firefight along the digestive border, your body perceives a foreign intruder and assigns its special forces—mast cells and macrophages—to eliminate the culprit. These are the cells that start an immune-response process throughout your body by ingesting foreign elements and alerting the rest of your body’s protecting cells that intruders have entered the area. Foods that don’t agree with your body’s sensibilities are seen as foreign invaders, so the macrophages attack these foods and tell everyone that this war is going on. This causes your whole body to start firing away at these foods and at innocent bystanders—and thus causes inflammation in your bloodstream. In that way, eating unhealthy food is really like having a chronic infection that triggers an immune response, which then causes inflammation.

One of your body’s goals is to get glucose into your brain cells—to feed those brain cells so that they can function. But inflammation in your body prevents sugar from getting to those cells, so you end up wanting more glucose and eating more sugary foods, which then increase inflammation and starts the whole cycle again.

FACTOID

Probiotics like lactobacillus GG or Bifidus Regularis repopulate your small intestine’s bacteria with healthful bacteria, especially after a course of antibiotics. The good bacteria calm down the dangerous ones-meaning that they can help you have less GI irritation, less gas, and less risk of an inflammatory uncivil war breaking out.

While we should be concerned about decreasing our body fat, we should also concentrate on decreasing our body’s inflammatory response so we become more efficient in managing potential complications of our waist size. There’s some genetic component to inflammation (some us have more than others, and smokers tend to have higher levels of inflammation than nonsmokers). Most important, the process of gaining weight is often a process of inflammation. YOU-reka! When you decrease your body’s inflammatory response, you will decrease your weight and waist as well.

The more inflammation you have, the less efficiently you use your food calories, and the worse you feel. The worse you feel, the more bad foods you eat to try to make yourself feel better. The more bad food you eat, the less well you can respond to the normal stresses of life, and the more inflammation you experience. And the more inflammation you have, the higher your risk of developing:

 diabetes

 high blood pressure

 bad cholesterol numbers

 and all of the other conditions that contribute to your increase in size and your decrease in health

Plain and simple: Inflammation ages your body by making your arteries less elastic and by increasing atherosclerosis (the rusting of blood vessels). Inflammation also makes it more likely that your DNA will be damaged, and a cell will become cancerous. And it increases your risk of infections. If the inflammatory mediators are fighting in the arteries, they can’t be defending elsewhere, and this situation increases the risk that your body will turn on itself, causing an autoimmune disease in which you attack your own tissues (for example, some forms of rheumatoid arthritis and thyroid disease).

FACTOID

We have two main sources that power nature’s rear-propulsion system. Gas comes from the air we swallow (20 percent) and the digestion of foods by bacteria in our intestines (80 percent). These bacteria love digesting sugars, fiber, or milk (if you’re lactose-deficient). The result is lots of gas made up of carbon dioxide, nitrogen, and methane (which—duck!—is flammable). You can reduce swallowing air by avoiding cigarettes, gum, and carbonated beverages, or by eating and drinking more slowly.

Inflammation stresses your body

Inflammation fattens your body.

Obesity isn’t just a disease of doughnuts and baked ziti. Obesity is a disease of inflammation. As we travel through the rest of our digestive journey, well be stopping at three digestive landmarks to see how foods influence inflammation and how inflammation influences fat:

Your Major Interstate of Food: Your Small Intestine. This approximately twenty-foot-long organ (it’s about three times your height) serves as your second brain, deciding which foods agree with your body and which foods cause your body to rebel like sixth graders with a substitute teacher.

Your Parking Lot of Fat: Your Omentum. The omentum, which is located next to your stomach, serves as your primary storage facility of fat, where you park some or (in really bad cases) all the excess foods you eat. Ideally, the garage is empty. But as we gain weight, some of our bellies are housing four stories of Winnebago-worthy fat. Most important, the omentum serves as our body’s ultimate stress gauge: YOU-reka! As we’ll explain in a moment, bigger bellies indicate higher levels of inadequately managed chronic stress—which causes chronic levels of inflammation.

Abdominal Pain Is a Pain in the Neck

Your abdominal discomfort may be caused not by what’s happening inside your belly but by what’s happening outside. According to one researcher, there’s such a thing as Tight Pants Syndrome, which is abdominal pain lasting two to three hours after a meal. Its cause? Yup: pants that are too tight. (The researcher says there’s as much as a three-inch difference between waist size and waistband.) Funny, but the same thing happens with men and shirt size. Two-thirds of men purchase shirts with a neck size that’s too small, so they get headaches, changes in vision, and even changes in blood flow to and from the brain.

Your Post Office Processing Facility: Your Liver. Your liver is the second-heaviest organ in your body (the largest, your skin, is actually twice as heavy) and is your body’s metabolic machine. Your liver works a lot like an urban postal center, taking in all the incoming mail (in terms of nutrients and toxins), sorting it, detoxifying it, and then shipping it off to different destinations for your body to use as energy.

While the three organs all play different roles, the upshot of their relationship is this: The small intestine initially processes your food, and your omentum helps store it. Inflammation occurs in your small intestine and omentum, but the big battle happens in your liver, where the mother of all inflammatory responses takes place. That’s the one that makes you store fat—and experience the unhealthy effects of it.

FACTOID

Fat is like an organ, but the omentum is the supercharged version. Omentum fat has more blood supply than any other kind of fat and is quickest to mobilize itself to feed the liver.

Yes, we know that in-your-gut physiology isn’t always pretty, but we want you to keep in mind our main gut goal: By understanding how food travels through this leg of your digestive system, you’ll be able to identify the foods that will help you reduce harmful and weight-related inflammation. When you do that, you’ll have signed a digestive peace treaty that can end the war on your waist.

FACTOID

About 10 percent of Americans have fatty livers that are overwhelmed with fat sent from the intestines and omentum for processing. Fatty livers can lead to fibrosis-reduced liver function, and even the serious liver disease cirrhosis over time, although for most folks, you just end up looking like foie gras on the insides.