Dietary fibers are plant-based complex carbohydrates that cannot be broken down or digested and play an important role in maintaining overall health. Find out more about the benefits of high fiber foods!
Fibers play such an important role in maintaining overall health. They lower cholesterol, prevent disease, fight obesity, lower the risk for cancers, and enhance intestinal health.
Learn more about where to find high fiber foods and how much fiber you need to consume.
Fiber In Your Diet
On average, as an American you get about 12 – 15g of fiber daily from your diet, which is approximately 50% of what you need to experience the benefits that are associated with a high fiber diet.
There are other countries in the world where you can find an abundance of fiber in the average diet.
One such place is China, where the average Chinese citizen consumes approximately 77g of fiber daily!
If we take a look at the restaurants most Americans frequent rather often, Fast Food Chains like McDonalds, where can you find fiber?
Maybe the pre-packaged apple slices you can buy have some fiber in them. The point is that you won’t find any foods at, for instance, McDonalds that are high in fiber.
Unfortunately most Fast-Food restaurants do not provide high fiber foods, which is unfortunate since most Americans eat there because fast food chains provide the cheapest food, advertise heavily, and are conveniently located.
Unfortunately, fiber consumption and death rate are correlated.
In all studies that include a High-Fat-Low-Fiber diet, incidences of heart disease and cancer are high.
You will soon find out what the lack of fiber in your diet means with respect to disease prevention but having too much fiber prevents the proper absorption rate of fat-soluble vitamins (Vitamin A, D, E, and K).
So how come fiber has such an impact on your health?
Important Benefits of High Fiber Foods
Fibers play such an important role in maintaining overall health because they can prevent diseases such as:
- heart & vascular disease
Fibers accomplish this via different mechanisms but most importantly fibers:
- Lower Cholesterol
- Lower the Glycemic Index
- Increase Thermo Effects of Foods
- Reduce exposure to carcinogens
- Increase Intestinal Health
Fiber Reduces “Bad” Cholesterol
Fiber lowers cholesterol by binding intestinal lipids, hence preventing the absorption of fat (cholesterol).
The mechanism is that soluble fibers bind to intestinal lipids preventing the absorption of fat.
Again, having too much fiber in your diet prevents the proper absorption rate of fat-soluble vitamins (Vitamin A, D, E, and K).
This does not mean that when you eat fibers that you will be able to eliminate getting certain diseases (e.g. heart disease, cancer).
What it means is that one can observe an association between lack of fibers in the diet and the risk of getting certain diseases.
In other words, the likelihood/risk of developing cancer or heart disease, for instance, is higher when one consumes inadequate amounts of fiber in the diet vs. following a diet high in fiber.
The daily adequate intake (AI), the average amount consumed by healthy people, of fibers for males is 38g and 25g for females, respectively.
Fiber Reduces the Glycemic Index
The Glycemic Index (GI) indicates how quickly food is being absorbed to provide energy and hence raise blood glucose levels.
Whenever you eat fibers with carbohydrates, they lower the insulin response naturally because fibers slow down the gastric emptying process, decrease the absorption of glucose, and reduce insulin spikes.
Because of the aforementioned benefits, fiber has a positive effect on preventing diseases such as:
- Heart disease
Fiber Increases Thermo Effects of Food
When you eat foods rich in fiber, the body will try to digest it, which it cannot do, thereby working muscles hard in the gastrointestinal (GI) tract that are trying to break down the fiber.
Because smooth muscle cells are found in the lining of the GI tract, (that also have actin & myosin, just like other muscle cells) you are burning a lot of calories in the process of digestion (energy; heat), hence creating the thermic effect of food.
Because of the increased digestive muscle activity, the thermo effect of food has an impact in fighting obesity.
Fiber Reduces Exposure to Carcinogens
Carcinogens are cancer-causing agents and fiber has the ability to dilute them by adding bulk (increases fetal bulk) to digestion.
By doing so it really reduces the synergies of carcinogens and hence lowers the risk for cancers.
Fiber Increases Intestinal Health
Fiber forms short-chain fatty acids in the intestine (butyrate), which has been shown in research studies to elicit cancer cell death and reduce GI tract inflammation.
Sources of Fiber
As far as (water) soluble fibers go, Beans, Oats, and Nuts (BON) lower cholesterol. Insoluble fibers (e.g. vegetable, fruits) help increase the thermic effects of food, reduce the exposure to carcinogens (these are certain cancer-causing agents), and increase interstitial health.
Generally speaking, stay away from processed foods and buy more agricultural foods. Various supplements and pills might offer a cost-effective and convenient alternative.
According to dietary guidelines (ACSM), the following foods represent good sources of fiber:
- Bread, Cereal, Pasta, Rice
- Use 100% Whole Wheat Bread, pumpernickel, or rye bread
- Use cereal with a minimum fiber content of 5g (e.g. 100% bran cereal)
- Eat oatmeal or grits regularly
- Brown rice
- Eat a variety of different veggies (potatoes, corn, lettuce, etc.)
- When eating out, order (steamed) veggies on the side (e.g. broccoli)
- Try drinking vegetable juices instead of sodas
- Have large salads (beware of dressing; no Taco salads!) instead of burger, etc.
- Try mixing up veggies’ taste and color (broccoli, cabbage, carrots, corn, green peas, beans, spinach, potatoes)
- Add veggies whenever possible (e.g. veggie pizza)
- Start day with glass of orange juice or grapefruit juice (not concentrate)
- Use fresh or dried fruits as between-meal snacks (apple, banana, kiwi, peach, nectarine, orange)
- Choose variety of fruits; different colors
- Choose lean cuts (“loin” and/or “round”)
- Trim visible fat
- Choose wild (living) over farm-raised products (e.g. fish)
- Eat meat in moderation (e.g. couple times/week)
- Try soy alternatives
- skin milk or 1% fat milk
- more reduced-fat cheese than regular cheese
- Use low-fat or fat-free products (e.g. ice cream)
Recommended Intakes of Fiber
According to dietary guidelines, based on a 2,000kcal diet one should consume 900 – 1,300 kcal of carbohydrates (225 – 325g), depending on the carbohydrate range used (45 – 65% of nutrients should come in form of carbs).
This amount of fiber is adequate, surpassing the RDA (Recommended Daily Allowance) of 130g/day, which is based on how much glucose the brain uses at a minimum to function properly.
The DRI (Dietary Reference Intakes) recommends consuming 14g/1,000kcal/day of fiber, whereas the American Dietetic Association suggests 20 – 35g (80 – 140kcal) of dietary fiber daily, which is more than twice the amount of fiber consumed by most Americans!
In more detail, the DRI recommends:
- For Men:
- 19 – 50 years: 38g/day
- 51+: 30g/day
- For Women:
- 19 – 50 years: 25g/day
- 51+: 21g/day
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