Dietary Fiber is an important component of a healthy balanced diet
Dietary Fiber, also known as roughage or bulk, is a type of complex carbohydrate include in all parts of plant foods that our body can't digest or absorb. Unlike other food components such as fats, proteins or carbohydrates - which our body breaks down and absorbs - dietary fiber is not digested by our body. Therefore, it passes relatively intact through our stomach, small intestine, colon and out of our body. It might seem like fiber doesn't do much, but it has several important roles in maintaining health. It adds bulk to our diet and makes us feel full faster, helping us control our weight. Dietary Fiber helps digestion and helps prevent constipation.
We can get dietary fiber from whole grains, beans, nuts, fruits and vegetables. Eating a large amount of dietary fiber in a short period of time can cause intestinal gas (flatulence), bloating and abdominal cramps. This usually goes away once the natural bacteria in the digestive system get used to the increase in dietary fiber in the diet. Adding dietary fiber gradually to the diet, instead all of adding it at once, can help reduce gas or diarrhea.
Too much dietary fiber may interfere with the absorption of minerals such as iron, zinc, magnesium and calcium. However, this effect usually does not cause too much of concern because high-fiber foods are typically rich in minerals.
The short-term effect of a low fiber diet is usually constipation. A high dietary fiber diet prevents constipation and hemorrhoids (piles). It stimulates the muscles of the digestive track to retain their tone. Over the long-term, a low fiber diet may increase the risk of heart disease, stroke, diabetes and gastrointestinal conditions.
Current recommended dietary intake (RDI) suggests that children and adults consume at least 20 grams of dietary fiber per day from food, not supplements. The more calories you eat each day, the more fiber you need; teens and men may require upwards of 30 to 35 grams per day or more.
Dietary Fiber is commonly classified into two categories: those that don't dissolve in water (insoluble fiber) and those that do dissolve in water (soluble fiber).
- Insoluble Fiber: This type of dietary fiber promotes the movement of material through your digestive system and increases stool bulk, so it can be of benefit to those who struggle with constipation or irregular stools. Whole-wheat flour, wheat bran, nuts and many vegetables are good sources of insoluble fiber.
- Soluble Fiber: This type of dietary fiber dissolves in water to form a gel-like material. It can help lower blood cholesterol and glucose levels. Soluble fiber is found in oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium.
The amount of each type of fiber varies in different plant foods. To receive the greatest health benefit, eat a wide variety of high-fiber foods.
Carbohydrates (carbs): Simple Carbohydrates, Complex Carbohydrates
Our body uses carbohydrates (carbs) to make glucose which is the fuel that gives us energy and helps keep everything going. Our body can use glucose immediately or store it in our liver and muscles for when it is needed. So, the primary function of carbohydrates is to provide energy for our body, especially the brain and the nervous system. An enzyme called amylase helps break down carbohydrates into glucose (blood sugar), which is used for energy by our body.
Carbohydrates are found in a wide array of foods like fruits, sweets, soft drinks, breads, pastas, beans, potatoes, bran, rice and cereals. They also come in a variety of forms. The most common and abundant forms are sugars, fibers and starches.
The basic building block of every carbohydrate is a sugar molecule, a simple union of carbon, hydrogen and oxygen. Starches and fibers are essentially chains of sugar molecules. Some contain hundreds of sugars. Some chains are straight, others branch wildly.
Carbohydrates were grouped into two main categories. Simple carbohydrates included sugars such as fruit sugar (fructose), corn or grape sugar (dextrose or glucose), and table sugar (sucrose). Complex carbohydrates included everything made of three or more linked sugars. Complex carbohydrates were thought to be the healthiest to eat, while simple carbohydrates weren't so great. Complex carbohydrates are carbohydrates that take longer to break down into glucose.
The digestive system handles all carbohydrates in much the same way - it breaks them down (or tries to break them down) into single sugar molecules, since only these are small enough to cross into the bloodstream. It also converts most digestible carbohydrates into glucose (also known as blood sugar), because cells are designed to use this as a universal energy source.
Some diet books use "Bad" carbs to talk about foods with refined carbohydrates (i.e., meaning they are made from white flour and added sugars). Examples include white bread, cakes and cookies. On the other hand "Good" carbs is used to describe foods that have more dietary fiber and complex carbohydrates.
Healthier foods higher in carbohydrates include ones that provide dietary fiber and whole grains as well as those without added sugars.
What about foods higher in carbohydrates such as sodas and candies that also contain added sugars? Those are the ones that add extra calories but not many nutrients to our diet.
Proteins: Complete Proteins, Incomplete Proteins
Proteins, are complex organic compounds which are present in and vital to every living cell or every cell in the human body contains protein, therefore proteins can be describe as fundamental components of all living cells. In the form of skin, hair, glands, organs, muscles, cartilage and ligaments, proteins hold together, protect and provide structure to the body of a multi-celled organism. In the form of enzymes, hormones, antibodies and globulins, they catalyze, regulate and protect the body chemistry. In the form of hemoglobin, myoglobin and various lipoproteins, they affect the transport of oxygen and other substances within an organism, which are necessary for the proper functioning of an organism. Protein is also found in all body fluids, except bile and urine.
Protein builds up, maintains and replaces the tissues in our body. We need protein in our diet to help our body repair cells and make new ones. Protein is also important for growth and development during childhood, adolescence and pregnancy. Our body uses the protein we eat to make lots of specialized protein molecules that have specific jobs. In fact, whether we are running or just hanging out, protein is doing important work like moving our legs, moving our lungs and protecting us from diseases.
The basic structure of protein is a chain of amino acids. When we eat foods that contain protein, the digestive juices in our stomach and intestine go to work. They break down the protein in food into basic units, called amino acids. The amino acids then can be reused to make the proteins our body needs to maintain muscles, bones, blood and body organs.
Proteins are sometimes described as long necklaces with differently shaped beads. Each bead is a small amino acid. These amino acids can join together to make thousands of different proteins. Scientists have found many different amino acids in protein, but 22 of them are very important to human health.
Of those 22 amino acids, our body can make 13 of them without us ever thinking about it. Our body can't make the other 9 amino acids, but we can get them by eating protein-rich foods. They are called essential amino acids because it's essential that we get them from the foods we eat.
Protein containing foods are grouped as either complete or incomplete proteins. Complete proteins contain all nine essential amino acids. Complete proteins are found in animal foods such as meat, fish, poultry, eggs, milk and milk products such as yogurt and cheese. Soybeans are the only plant protein considered to be a complete protein.
Incomplete proteins lack one or more of the essential amino acids. Sources of incomplete protein include beans, peas, nuts, seeds and grain. A small amount of incomplete protein is also found in vegetables. But most of the vegetable protein is considered incomplete. This can be a concern for someone who doesn't eat meat or milk products. But people who eat a vegetarian diet can still get all their essential amino acids by eating a wide variety of protein-rich vegetable foods.
For instance, we can't get all the amino acids we need from peanuts alone, but if we have peanut butter on whole-grain bread we are set. Likewise, red beans won't give us everything we need, but red beans and rice will do the trick. The good news is that we don't have to eat all the essential amino acids in every meal. As long as we have a variety of protein sources throughout the day, our body will grab what it needs from each meal.
A diet high in meat can contribute to high cholesterol levels or other diseases such as gout. A high-protein diet may also put a strain on the kidneys.
Fats and Cholesterol
Fats are organic compounds that are made up of carbon, hydrogen and oxygen. They are a source of energy in foods. Fats belong to a group of substances called lipids and come in liquid or solid form. All fats are combinations of saturated and unsaturated fatty acids.
There are three families of lipids: (1) fats, (2) phospholipids, and (3) steroids.
Fat is one of the 3 nutrients (along with protein and carbohydrates) that supply calories to the body. Fat provides 9 calories per gram, more than twice the number provided by carbohydrates or protein.
Fats and lipids play critical roles in the overall functioning of the body, such as in digestion and energy metabolism. Usually, 95 percent of the fat in food is digested and absorbed into adipose, or fatty, tissue. Fats are the body's energy provider and energy reserve, which helps the body maintain a constant temperature. Fats provide essential fatty acids, which are not made by the body and must be obtained from food. The essential fatty acids are linoleic and linolenic acid. They are important for controlling inflammation, blood clotting, and brain development.
Fat serves as the storage substance for the body's extra calories. It fills the fat cells (adipose tissue) that help insulate the body. Fats are also an important energy source. When the body has used up the calories from carbohydrates, which occurs after the first 20 minutes of exercise, it begins to depend on the calories from fat.
Healthy skin and hair are maintained by fat. Fat helps the body absorb and move fat soluble vitamins like vitamins A, D, E and K through the bloodstream.
Saturated fats do not have double bonds and are solids at room temperature. These are the biggest dietary cause of high LDL levels ("bad cholesterol"). When looking at a food label, pay very close attention to the percentage of saturated fat and avoid or limit any foods that are high. Saturated fat should be limited to 10% of calories. Saturated fats are found in animal products such as butter, cheese, whole milk, ice cream, cream, and fatty red meats. They are also found in some vegetable oils - coconut, palm and palm kernel oils. (Note: Most other vegetable oils contain unsaturated fat and are healthy.)
Unsaturated fats have one or more double bonds and are liquids at room temperature. Fats that help to lower blood cholesterol if used in place of saturated fats. However, unsaturated fats have a lot of calories, so you still need to limit them. Most (but not all) liquid vegetable oils are unsaturated. (The exceptions include coconut, palm, and palm kernel oils.) There are two types of unsaturated fats:
- Monounsaturated (Omega 9) fats: Examples include Canola Oil, Olive Oil, Almonds, Avocado and Cashews.
- Polyunsaturated (Omega 6) fats: Examples include Safflower Oil, Sunflower Oil, Corn Oil and Soybean Oil.
- Polyunsaturated (Omega 3) fats: Examples include Walnuts, Flax Seeds, Salmon Fish and Hemp Seeds.
Trans Fatty Acids (Trans Fats)
These fats form when vegetable oil hardens (a process called hydrogenation) and can raise LDL levels. They can also lower HDL levels ("good cholesterol"). Trans fatty acids are found in fried foods, commercial baked goods (donuts, cookies, crackers), processed foods and margarines.
Hydrogenated and partially Hydrogenated Fats
This refers to oils that have become hardened (such as hard butter and margarine). Partially hydrogenated means the oils are only partly hardened. Foods made with hydrogenated oils should be avoided because they contain high levels of trans fatty acids, which are linked to heart disease.
Bottom-line, the total amount of fat we eat, whether high or low is not really linked with disease. What really matters is the type of fat we eat. The "bad" fats - saturated and trans fats - increase the risk for certain diseases. The "good" fats - monounsaturated and polyunsaturated fats - lower disease risk. The key to a healthy diet is to substitute good fats for bad fats
Water: How much should we drink every day?
Water is our body's principal chemical component and makes up 50 to 70 per cent of an adult's total body weight and without regular top-ups; our body's survival time is limited to a matter of days.
Water or fluid is a vital component of our diets, even though it's not considered a specific nutrient. Water's essential for the body's growth and maintenance, as it's involved in a number of processes. For example, water flushes toxins out of vital organs and regulates temperature, and it provides a medium for biological reactions to occur in the body. Bottom-line, every system in our body depends on water.
Every day we lose water through our breath, perspiration, urine and bowel movements, and must be replaced through the diet. If we don't consume enough we can become dehydrated, causing symptoms such as headaches, tiredness and loss of concentration. Chronic dehydration can contribute to a number of health problems such as constipation and kidney stones.
Our body gets its fluid from three sources:
- Drinks, either plain water or as part of other beverages including tea, coffee and squash
- Solid foods, especially fruit and vegetables (even foods such as bread and cheese provide small amounts of fluid)
- As a by-product of chemical reactions within the body
So how much water does the average, healthy adult living in a temperate climate need? In general, doctors recommend 8 or 9 cups. The Institute of Medicine advises that men consume roughly 3 liters (about 13 cups) of total beverages a day and women consume 2.2 liters (about 9 cups) of total beverages a day.
Even apart from the above approaches, if we drink enough fluid so that we rarely feel thirsty and produce 1.5 liters (6.3 cups) or more of colorless or slightly yellow urine a day, our fluid intake is probably adequate.
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