Eating well on the Planet Earth

Dietary Fiber and Water

Fiber isn't usually considered a nutrient, since it can't be digested by humans.

However we do need to eat fiber if we want to be healthy and comfortable.

Water isn't commonly thought of as a nutrient either, but it is necessary for us to live.

All the ecosystems on the planet depend on water. Without it we wouldn't be able to grow our food supply, and all the carbon-based life forms here on earth would die, many within a few days, if they didn't have access to water.

Dietary Fiber

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Did you ever wonder how a cow can survive, get fat and produce milk on a diet of grass? A cow’s specialized stomach with 4 compartments can digest the cellulose in plants. We humans are not able to break down the bonds in cellulose and absorb those nutrients. The parts of plants that we eat but cannot digest are called dietary fiber. Even though we cannot absorb fiber, it still plays an important part in the diet. Research is beginning to show that fiber is important in preventing or treating several diseases. Here are some of the things that fiber can do for you.

Soluble and Insoluble Dietary Fiber

Insoluble fiber is, as the name suggests, not soluble in water. It stays right in your digestive tract on it's journey through your body, doing all its good deeds along the way. First it makes you chew your food longer, forcing you to slow down with your eating. In the stomach it provides bulk which distends the stomach and sends your body the message that there is plenty of food here, and you can stop eating now. In the intestines it attracts water, making your stools softer and preventing constipation.

Good sources of insoluble fiber

Soluble fiber dissolves in water to form a gel. It also moves through your digestive tract without being absorbed, but in the meantime it can bind with substances such as fatty acids in the intestine. This is the form of fiber that can help to lower your blood cholesterol and glucose levels.

Good sources of soluble fiber

Dietary fiber is measured in grams (g). No distinction is made between how much soluble and insoluble fiber you need each day. As a rule of thumb you should try to get fiber from a wide range of fruits, vegetables and whole grains. See your daily requirement for fiber.

Fermentable and Functional Fiber

Granola is a good source of dietary fiber.

Fermentable fiber is easily fermented by the bacteria that live in the colon. This fermentation produces short chain fatty acids that can be metabolized for energy. This process also increases the amount of good bacteria living in the colon. Oats, barley, fruits and vegetables are fermentable, while cereal grains such as wheat and cellulose are not.

The Institute of Medicine defines functional fiber as isolated, nondigestible carbohydrates that have beneficial physiological effects in humans. They may have been isolated from a natural source, or they may have been synthesized. In order to be labeled functional fiber they must have a proven health benefit. Some functional fibers include psylllium, from psyllium husks, chitin, which comes from the exoskeletons of crustaceans, and the synthetic Fructooligosaccharides, Polydextrose and polyols.

Eight Reasons to Eat More Dietary Fiber

If you are on a gluten free diet you need to really pay attention to fiber, as you are eliminating a major source of fiber from your diet. Along with fresh fruits and vegetables, make sure you eat plenty of gluten free grains such as rice, corn, millet, teff, amaranth, sorghum and buckwheat (yes, it’s not wheat). This can help lower your cholesterol, which is a problem for many gluten intolerant people.

Fiber should be increased gradually in the diet or it could result in bloating, cramping or gas. You should also make sure to drink plenty of water as your body needs this in order for the fiber to work properly in the intestines. Certain types of fiber such as pectin, psyllium and guar gum can interact with medications, so be sure to check on this before taking fiber supplements.

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About two thirds of our bodies are water, and all of our cells require water to work properly. We can go for weeks without food, but will only last a few days without water.

How do our bodies use water?

Water is used to cool the body through perspiration, to move food through the digestive tract, to make up most of the volume of our blood and other body fluids, including the fluid surrounding the joints, brain, eyes and spinal cord, mucous and saliva. Digestion of proteins and carbohydrates depends on water.

How Much Water is Enough?

Our bodies are very good at regulating water balance. If the balance is low, the kidneys will conserve water by concentrating the urine, and we become thirsty, which reminds us to take in more water. About three fourths of the water we lose each day is through the kidneys. We also lose water through perspiration, water exhaled in the breath, and water in the feces. The amount of water depends on many factors, such as our size, the temperature or climate where we live, activity level, age and state of health. For this reason there is no daily requirement set for water, however an Adequate Intake has been calculated for different age groups. You would need to adjust this if you are extremely active, if you live in a very dry climate, etc. See the Adequate Intake level and find out more about the AI.

On the average, a person needs 8-12 cups of water per day. This may sound like a lot, but you get a lot of water without even realizing it. Crisp vegetables such as lettuce and celery can be 90% water. Even meats and grains contain some water. All beverages, including milk, are a source of water. You get water through food preparation of things such as soups and hot cereals, rice and other grains cooked in water. You should also try to drink 6-8 cups of water during the day to make up the difference.

Bottled Water vs Tap Water

Bottled water has become a huge industry, at least in the United States. According to the International Bottled Water Association (IBWA), Americans bought 5 billion gallons of bottled water in 2001. Is it worth it to buy bottles of water when you can get it from the tap for the cost of your city water bill? Many people believe bottled water is more pure, but this isn't necessarily true. In the US the Food and Drug Administration regulates both bottled water and tap water, and in most instances the standards for the two are the same. A company that bottles water may go above and beyond the standards to filter and purify their product, but they are not required to do this. You would need to check out each individual company to find out the standards of their water.

There are times when it makes sense to use bottled water. If you are on the road and want to have a ready water supply, if your tap water tastes really awful because of metals or chlorine, if you happen to know there is a contaminant in your city water or your well, bottled water makes sense. If you drink mostly bottled water you may not be getting any fluoride, which is often added to a public water supply. If this is an issue you should choose a brand of bottled water with fluoride added.

Water is a Precious Commodity

Here in the United States we have the luxury to choose bottled water or tap water, and worry about little things like a metallic taste or whether fluoride is added. In many other parts of the world water is a precious commodity, and people feel lucky to have any at all. Many countries are just plain short of water because of a desert climate, especially developing countries where they don't have the infrastructure to bring water in. For many other people its a question of clean water. Because of poverty, natural disasters or war, they don't have access to a clean water supply, and are at a risk for all sorts of diseases such as cholera, hepatitis or schistosomiasis. Some areas have high levels of natural fluoride, arsenic or other toxic metals in the water and don't have the means to remove it.

For in depth information about the water situation around the world visit The Water Page. To find out more about water-born diseases around the world visit the World Health Organization.

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