Most health experts today would agree that getting enough fiber in your diet is important to attaining and maintaining overall good health, especially due to our increasingly sedentary lifestyle. Lack of exercise slows the passage of food through the intestines. The more you sit, the less things move and this is where fiber can help.
Fiber is the natural substance found in fruits, vegetables and grains that acts as a “backbone” for plants, giving them their structure and shape. This type of fiber in your diet is called “insoluble” fiber because it does not break down; it simply passes through your small intestine and into your colon where it helps “get things moving” and, in the right quantity, fiber becomes an essential part of a healthy digestive process. Insoluble fiber moves through the colon almost intact which helps to add bulk to the rest of the material in the colon. It also acts like small wire brushes on the inside of your colon, removing matter that may have become impacted, sometimes for much longer than is normal or healthy. The bulk and the fiber move together as one, thereby helping to move colon contents effectively and smoothly through the length of the colon. Colon contents, fiber, and the moisture that is left in the large intestine, form a proper stool which can then be easily eliminated.
Fiber’s influence reaches farther than just your intestines. For example, if you consume fiber at the same time as saturated fat, the fiber helps remove a substantial portion of the saturated fat before too much of it accumulates in your bloodstream or before the bulk of it is digested.
Fiber can also help to lower blood cholesterol, normalize blood sugar levels, accelerate weight loss, and lower your risk of diabetes and heart disease. And because fiber is so closely associated with a healthy bowel, it’s important to remember that any part of your body that isn’t used regularly starts to become ineffective at its job. Fiber is one of the important partners which will help your colon work effectively. Your large intestine moves content using a process called mass movement; long, slow-moving but powerful contractile waves over large areas of the colon that force content toward the rectum. If your colon can move content easily, it works that much more effectively, and your colon stays healthy.
Types of Fiber
How Much Fiber Do You Need?
There are two types of fiber, soluble and insoluble.
Soluble fiber dissolves in water to form a gel-like material. It also dissolves in your body. It can help lower blood cholesterol and glucose levels. Soluble fiber is found in oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium. Psyllium is a type of plantain, the seeds of which are used as a bulking agent or laxative.
Insoluble fiber promotes the movement of material through your digestive system. Whole grains, wheat bran, nuts, seeds (such as flax seed) and many vegetables are good sources of insoluble fiber.
The National Academy of Sciences’ Institute of Medicine, which provides science-based advice on matters of medicine and health, gives the following recommendations for adults1 regarding Recommended Daily Intakes (DRI):
How Much Fiber?…What Does That Look Like?
What Does That Look Like?
The first thing that generally comes to mind when you think of fiber is breakfast cereals. Try to make sure you’re choosing one low in sugar and high in quality fiber. Cited below are other common foods and their fiber content so that you can reasonably estimate how much fiber you’re getting every day. Even better, become a label-reader to ensure the foods you’re eating are giving you your daily recommended amount of fiber.
Signs You Need More Fiber
On the flipside, not enough fiber in your diet can upset the way your digestive system is meant to work. When your daily fiber intake drops, or you consistently don’t get enough fiber, you can experience constipation. Digested foods begin having a hard time passing easily through your intestines. When this happens, straining to pass stools can cause hemorrhoids. Taken one step further, a lack of fiber may lead to diverticular disease; the inflammation of pouches that line your intestines called the diverticulum. Think you’re getting enough fiber already? Here are four signs that might indicate you actually need more:
Constipation – If you’re having fewer than three bowel movements a week, and the stools are hard and dry, you’re constipated. There are other factors that can lead to this (medications, lack of exercise and certain supplements) but adding more fiber into your diet is generally an adequate solution to the problem.
Weight Gain – Want to feel fuller longer? Eat more fiber. When you’re not craving food, you’re eating less and the weight begins to subside. It’s recommended you drink more water as well, not only to offset the amount of fiber you’re eating, but it’s now known that hunger sometimes translates as thirst rather than a need for more food.
Blood Sugar Fluctuations – Because fiber delays the absorption of sugar, helping you control blood sugar levels, try adding more fresh products, beans and peas, brown rice and other high-fiber foods to your diet.
Diet-Related Nausea & Fatigue – Getting most of your calories from a high-protein/low-carbohydrate diet – one rich in meat, eggs, and cheese and low in produce – may lead not only to a rise in cholesterol but also leave you nauseous, tired and weak. Try boosting your dietary fiber with the vitamin and mineral-rich whole grains, fruits and vegetables your body needs and cut back on fatty foods.2
Sources of Fiber
Slow And Steady Wins The Race
Increase the amount of fiber in your diet slowly and, at the same time, increase the amount of water you’re drinking as well. If too much fiber is consumed too quickly, there can be consequences.
- Because fiber increases the speed in which food moves through your digestive system, sudden increases of fiber can cause diarrhea.
- Because fiber binds with other substances, an over-abundance of fiber moving quickly through your intestines could interfere with the absorption of essential nutrients such as calcium, magnesium, iron and zinc.
- Too much fiber + not enough water = constipation and, in the extreme, intestinal blockage.
- Too much fiber over a short period of time can cause bloating and gas.
Grains and Whole Grain Products
The greatest amount of dietary fiber in wheat is in the outer layer, or bran, of the wheat grain. When white flour is produced, the bran layer is removed and the dietary fiber content of the flour is greatly reduced. Flour made from whole grains contains about three times as much dietary fiber as white flour.3
Whole grains, nuts, and seeds all contain essential fatty acids and B Vitamins; almonds are rich in vitamin E, magnesium, protein, and flavonoids; walnuts are high in omega-3; Brazil nuts are a good source of B vitamins, selenium, magnesium and calcium. Legumes and oats are sources of soluble fiber, brown rice and wheat bran are sources of insoluble fiber.
|Highest Fiber Fruits
Apples (soluble), Avocado, Berries (soluble & insoluble)
Dried fruits (figs, raisins, dates, apricots)
Orange, Kiwi, Pears (soluble), PrunesHighest Fiber Vegetables
Broccoli, Brussels sprouts, cabbage, carrots, mushrooms,
Greens: kale, collards, spinach, turnip greens,
potato with skin, squash, peppers, rhubarb, sweet potatoes.
Conditions and Diseases Fiber Can Help With
Blood glucose levels
Saturated fats are the fats you want to limit or stay away from as much as possible. But when you’re having that juicy steak or piece of fried chicken, who can resist the skin or fat? If you really must indulge, have some fiber with it. A three-bean side salad, or a side dish with lentils, will help remove most of the saturated fat you’ve just eaten before it has a chance to be digested by your body. Best of both worlds, right?
Blood Glucose Levels and Diabetes
It’s logical to consider these two conditions together as one typically influences the other. Although having said that, not everyone with a high blood glucose level has diabetes. But, for obvious reasons other than diabetes, it’s beneficial to know how to keep your blood glucose stable and at normal levels.
Your blood sugar levels are linked primarily to two things: the types and amounts of food you eat and your body’s ability to create and use insulin, a hormone that transports blood sugar into your body’s cells. Much of the food you eat is converted to blood sugar, which is used by the cells of your body for energy.4
Fiber, itself, does not raise blood glucose levels; actually slows the absorption of glucose. Of course, most of the foods containing fiber also contain other types of carbohydrates which should be accounted for if you’re watching your glucose levels or calories. A study in the New England Journal of Medicine showed that people with diabetes who ate 50 grams of fiber a day – particularly soluble fiber – were able to control their blood glucose better than those who ate far less. Oatmeal is an excellent example of this type of fiber.5
A bowl of soup or a snack of raw cauliflower and broccoli – which one do you think keeps you feeling fuller, longer? A no-brainer, right? So if weight loss is your goal, reach for the foods that stay in your stomach longer. Fiber makes us feel fuller sooner, slows our rate of digestion and keeps us feeling satiated, preventing us from taking that second helping or snooping around for a snack. For example, due to its greater fiber content, a single serving of whole grain bread is more filling than two servings of white bread.
And as previously stated, fiber helps move fat through our digestive system faster so that less of it is absorbed. In the April 1997 issue of the Journal of Nutrition, researchers reported that the more fiber volunteers ate, the more fat ended up in their stools.
Over and above fiber’s ability to keep us feeling full, foods with little to no fiber turn into blood glucose so fast that, like the “white crystalline devil” itself, they can cause a spike in insulin levels. This signals our body that plenty of energy is on hand and that it should stop burning fat and start storing it. What comes after a spike? – the deep, dark valley of hunger (once your insulin levels drop, also known as a sugar crash), leaving you feeling tired and hungry and on the prowl for more sugary foods. Eating foods with plenty of fiber will help keep blood glucose levels on a more consistent plane and help you shed unwanted pounds.
According to the U.S. National Digestive Diseases Information Clearinghouse, constipation is defined as, “having a bowel movement fewer than three times per week.” Constipation is a symptom, not a disease. Almost everyone, at some point, experiences constipation and typically, poor dietary choices that are low in fiber and high in fat are to blame. Sometimes constipation can lead to complications like hemorrhoids. Straining to have a bowel movement can also cause fissures which can bleed or become infected.
People who eat a high-fiber diet (20 to 35 grams daily) are less likely to become constipated. The bulk and soft texture of fiber help prevent hard, dry stools that are difficult to pass. Including more high-fiber foods and increasing your intake of water should correct the problem.
DISEASES – Diverticular Disease
Many people have small pouches in the lining of the colon or large intestine that bulge outward through weak spots. Each pouch is called a diverticulum. Multiple pouches are called diverticula. The condition of having diverticula is called diverticulosis. Diverticula are most common in the lower portion of the large intestine, called the sigmoid colon. When the pouches become inflamed, the condition is called diverticulitis (“itis” meaning inflammation). Ten to 25 percent of people with diverticulosis get diverticulitis. Diverticulosis and diverticulitis together are called diverticular disease. Diverticulitis can lead to bleeding; infections; small tears, called perforations; or blockages in the colon. These complications always require treatment to prevent them from progressing and causing serious illness.
Although not proven, the dominant theory is that a low-fiber diet causes diverticular disease. The disease was first noticed in the United States around the time processed foods were introduced into the American diet. A lack of fiber causes constipation. The straining that goes along with constipation causes increased pressure in the colon which may cause the colon lining to bulge out through weak spots in the colon wall.A high-fiber diet, in most cases, is a featured part of the prescription. Increasing the amount of fiber in the diet may reduce symptoms of diverticulosis and prevent complications such as diverticulitis.
According to the American Heart Association, “when eaten regularly卻oluble fiber has been associated with匸a] decreased risk of cardiovascular disease.” This is, largely in part, thanks to the fact that fiber helps reduce LDL (lousy cholesterol) when eaten in conjunction with a diet that is low in the “bad” fats (saturated and trans fats).
DISEASES – Heart Disease, cont.,
As far as soluble fiber goes, definitely include oats. Oats have the highest portion of soluble fiber of any grain. Foods high in insoluble fiber keep you fuller longer which means you eat less and keep extra weight at bay. This simple avoidance of extra weight leaves you at a decreased risk for cardiovascular events and helps slow the progression of cardiovascular disease.
Blood Cholesterol Levels
Fiber binds with cholesterol and may reduce the level of cholesterol in the blood. Studies have shown that consuming 10 to 25 grams of soluble fiber a day can lower cholesterol by 18%. However, it appears to only lower your “bad” (LDL) cholesterol – your “good” cholesterol (HDL) and triglycerides (type of fat) are only minimally, if at all, affected by soluble fiber..
Evidence suggests that soluble fiber is more effective at lowering cholesterol, but both types of fiber are important for your health. Another way soluble fiber may lower blood cholesterol is through its ability to reduce the amount of bile reabsorbed in the intestines. It works like this: when fiber interferes with absorption of bile in the intestines, the bile is excreted in the feces. To make up for this loss of bile, the liver makes more bile salts. The body uses cholesterol to make bile salts. So in order to obtain the cholesterol necessary to make more bile salts, the liver increases its production of LDL receptors. 6
To watch this short video called “The Top 10 Foods High In Fiber”, click here. Think you can quote them all?…keep watching, one of them will surprise you!
To watch this quick video on how to increase your fiber each day, narrated by Dr. Mary Ann Block, click here.
American Heart Association, “Whole Grains and Fiber”
Mayo Clinic, “Tips for Fitting In Fiber”
Harvard School of Public Medicine, “Fiber, Start Roughing It!”
National Institutes of Health, “Rough Up Your Diet”
“The Fiber35 Diet: Nature’s Weight Loss Secret” by Brenda Watson
It’s time to revolutionize the way you think about dieting! New York Times bestselling author Brenda Watson has an incredible secret that helped her transform her body and vastly improve the quality of her life — the Fiber35 Diet. This incredible program will show you how to lose those unwanted pounds and maintain optimal health by taking advantage of the extraordinary power of fiber.
“Fiber Boost: Everyday Cooking for a Healthy Long Life” by Amy Snider
Nutrition experts and health officials agree: We all need to eat more fibre in our diets in order to maintain health and prevent disease. But how do you make it taste good? How do you even manage to get the required intake? Fiber Boost is an appetizing collection of fibre-rich recipes for the fast-paced North American lifestyle.
CookingBread.com, High Fiber Bread Recipes “Whole Grains and Fiber”
FoodNetwork.com, High Fiber Recipes
Garden Vegetable Soup by Alton Brown
1. Mayo Clinic, Nutrition and Healthy Eating
4. “Stealth Health”, written by Debra L. Gordon and David L. Katz
5. “How Does Fiber Affect Blood Glucose Levels?”, Joslin Diabetes Center, Harvard Medical School
6. “Foods that Lower Cholesterol” by Adrienne Forman, MS, RD