Dietary Fibers
When fibers first appeared on the nutrition stage, they were heralded as a natural remedy for constipation-related problems and were marketed in that context. Research had shown that these indigestible plant products tended to travel through the GI system largely unchanged, had the ability to absorb water thereby softening and bulking stool, and made the defecation process easier. More interesting, however, was what later research revealed that a diet high in total fiber could
– reduce risk of other GI related conditions such as hemorrhoids, irritable bowel disease and development of polyps or diverticular disease (small pouches that develop in the large intestine from friction of hard stool against the intestinal lining)
– decrease risk of colorectal cancer (cancer of the large intestine).
– studies show significant decrease in men compared to women but conclusive data is still lacking
– reduce blood level of ‘bad’ cholesterol which is known to increase risk of strokes and heart disease
– decrease risk of developing diabetes by slowing down absorption of sugar in the blood
– prevent overeating by making you feel full sooner
– aid in weight loss as a dieting tool (fibers contain less calories per volume of food)
– reduce the risk of breast cancer in pre-menopausal women.
The mechanisms by which fibers achieve the above-mentioned positive health effects are not completely understood but it is thought that by helping to move stool through the GI system faster. Fibers decrease the absorption time of some nutrients and remove toxic substances that are stored in stool. Toxins in stool are equivalent to the bad smell released by decaying food that spreads throughout the house. Like the bad smell of decaying food, overtime toxins can make our bodies sick. It is similar to having a sink pipe clogged with left over food that over a couple of hours or days, make it hard for water to drain from the sink.
So how can we keep our internal pipes clean and working smoothly? One way is by changing our diet by increasing our intake of fruits, cereals, vegetables, beans and nuts.
Table 1 shows foods with relatively high fiber content which are easily accessible. For a more extensive food list, see the reference section. The recommended intake for women less than 50 years old is 38 grams and for men less than 50 it is 25 grams. For those older than 50, the recommended intake for men is 30 grams and for women it is 21 grams.
|
Food item |
Fiber content in grams* |
| Split peas, cooked, 1 cup | 16.3 |
| Red kidney beans, boiled, 1 cup | 13.1 |
| Raspberries, raw, 1 cup | 8.0 |
| Whole-wheat spaghetti, 1 cup | 6.3 |
| Oat bran muffin, medium | 5.2 |
| Pear, medium with skin | 5.1 |
| Broccoli, boiled, 1 cup | 5.1 |
| Apple, medium with skin | 4.4 |
| Oatmeal, quick, regular or instant, cooked, 1 cup | 4.0 |
| Green beans, cooked, 1 cup | 4.0 |
| Brown rice, cooked, 1 cup | 3.5 |
| Popcorn, air-popped, 2 cups | 2.3 |
| Whole-wheat bread, one slice | 1.9 |
Table 1: Foods high in fiber content by grams
Source: USDA National Nutrient Database for Standard Reference, 2007
http://www.mayoclinic.com/print/fiber/NU00033/METHOD=print
Fluids
In many ways, fluids work hand-in-hand with dietary fiber in helping to make our digestive system run smoothly and maintaining overall general body functioning. Considering the fact that our bodies are made up of 60% fluids, including our muscles, blood and brain, replenishing our daily fluids should be a prime goal. Of all available fluids, water is the best and the cheapest. Second to water are natural fruit and vegetable juices. Water is important for several cell and organ system functions including maintaining blood volume, removal of bodily waste in the form of urine, and temperature regulation through sweating. The daily recommended fluid intake is 8-12 glasses but varies greatly depending on body weight and existing conditions. For instance, fluid requirements are higher under extreme conditions like when exercising, being in hot or humid environments or when ill with a fever. As we strive to adopt healthier eating habits, it is also important to cut back on sodas or juices high in sugar. Substitute instead with whole fresh fruits that are great sources of both fiber and fluids.
For more dietary information for all age groups and to create your own personalized dietary plan, visit: http://fnic.nal.usda.gov
References:
1. Dietary fiber: An essential part of a healthy diet. Available at URL: http://www.mayoclinic.com/print/fiber/NU00033/METHOD=print
2. Comparisons of dietary content in various food items. Available at URL
http://www.healthyeatingclub.com/info/books-phds/books/foodfacts/html/data/data2c.html