Obesity is one of the most serious problems in America today. Sixty percent of Americans are overweight, and almost half of them are obese. Furthermore, many children are now obese - something you rarely saw a few decades ago. And the damage that obesity does to your body is immense; it causes high cholesterol, high blood pressure, high blood sugar and shortness of breath which in turn leads to heart attack, stroke, diabetes, cancer, osteoporosis and many other diseases.
One of the best ways to see the damage is to look at the effect that obesity has on the major markers of your health (frequently called biomarkers). Biomarkers are used routinely for monitoring your health. A large number exist, but in this article I'll restrict them to the eight most common. These eight give a good indication of how efficiently your heart, cardiovascular system, immune system and metabolism are operating, and how good your overall health is.
They are as follows:
- Your resting (basal) metabolic rate
- Body composition (percentage of muscle versus fat)
- Aerobic capacity
- Blood sugar level
- Cholesterol/Triglycerides
- Blood pressure
- Overall strength and muscle mass
- Bone density
I'll look at each of these in turn.
Resting Metabolic Rate
Simply, your metabolic rate is the rate at which you burn calories. Your resting or basal metabolic rate (BMR) is the minimum of this rate. Your BMR is important because it is related to the amount of muscle you have. The more muscle you have, the higher your BMR, and you want to keep it as high as possible. As you gain weight (most of which is fat), however, you lose muscle. So your BMR decreases, and as a result your "caloric need" (the calories needed to maintain your body functions) decreases. The problem with this is that most people continue to eat as they did when they had more muscle, and this adds even more fat, and the loss of more muscle. So it's a vicious circle that quickly leads to obesity.
Body Composition
The above problem shows us that it is important to keep a good ratio of muscle to fat. We refer to this as body composition. It's difficult to measure the amount of body fat you have directly, but a good indirect measurement of it can be obtained by determining your BMI, or Body Mass Index. To get it you multiply your weight in pounds by 703, and divide the resulting number by your height in inches squared (if you don't like math, tables can easily be found on the internet). In general, your BMI should be less than 25.
Another good measure is the distribution of your fat. Studies show that if you store most of your weight above your hips (as compared to below) you are in more danger of heart attack, stroke and diabetes. A good way to test this is to measure the distance around your waist with a flexible tape (above your hips), then measure the widest distance around your hips and buttocks. Divide the first number by the second. Women should have a ratio of less than.8; men should have less than.95.
Why is the percentage of muscle to fat in your body important? Basically it's because muscle is active tissue, and fat is generally inactive. This means that muscle burns more calories than fat. A given amount of muscle, for example, burns almost five times as many calories as the same amount of fat.
So, if a large amount of your weight is fat, it's very easy to get even fatter. If you want to lose fat and keep it off you have to change this ratio.
Aerobic Capacity
Aerobic capacity is a measure of how efficiently your body processes the oxygen that you take in. For a high aerobic capacity you need healthy lungs, a powerful heart, and a good vascular system. Your aerobic capacity is, in fact, one of the best indicators of your overall cardiovascular fitness. A simple way to test your aerobic capacity is to walk a mile, note how long it took you, and measure your heart rate. If you substitute these two numbers into a formula (it's rather complicated so I won't give it) it gives what is called your VO2 max, which is a measure of your aerobic capacity.
Obese people have a large amount of fat in and around their rib cage which causes shortness of breath, and lowers their V02 max. In addition, their heart muscles have deteriorated as they have been replaced by fat. The best way to increase your VO2 max is the exercise aerobically.
Blood Sugar Test
This is a measure of the amount of sugar in your blood. It is important because the carbohydrates that you eat are broken down into a sugar called glucose which is distributed throughout your body in your blood stream. Your body (particularly, your brain) need glucose and can only function properly when glucose levels are above a certain level. To get the glucose into your cells, however, the hormone insulin is needed. Most of the cells in our body have what are called insulin receptors that attract insulin. When insulin is bound to these receptors the cells allow the glucose to enter. If the receptors no longer work properly (mainly from lack of exercise), and don't allow sugar in, you are said to have "insulin resistance."
With no place to go, the sugar continues to circulate in the blood, and the cells begin to starve. The body realizes something is wrong and the pancreas produces more insulin in an attempt to get more sugar into the cell, but this causes the pancreas to overwork, and it soon begins to wear out. The result is diabetes II.
Cholesterol/Triglycerides
Cholesterol is a waxy substance the plays an important role in the body. It does not dissolve in blood so it needs a "carrier" to transport it where it is needed. This carrier is called a lipoprotein.
There are three forms of cholesterol:
LDL (low density lipoprotein)
HDL (high density lipoprotein)
VLDL (very low density lipoprotein)
LDL is considered to be "bad" cholesterol (VLDL is also bad); HDL is "good." LDL cholesterol can "stick" in the walls of your arteries and build up into what is called plaque. HDL cholesterol scours the arteries looking for excess LDL and fat, and it transports it to the liver for disposal. This means that you want to keep your LDL cholesterol low (below 100 mg/dL) and your HDL high (above 50 mg/dL).
As your body fat increases, your LDL cholesterol almost always increases along with it. At the same time your HDL levels decrease. Studies have shown that there is a definite link between your body fat and your cholesterol levels. The only way to bring them in line is to lose weight with the proper diet and exercise.
It's also important to keep your Triglycerides below 150 mg/dL. They give a measure of a certain type of fat in your bloodstream.
Blood Pressure
High blood pressure (hypertension) is another serious problem that comes with obesity. If untreated, it can cause stroke, heart disease and kidney problems. Two numbers are associated with your blood pressure: systolic and diastolic. In general, you want to keep your systolic reading under 140 and your diastolic under 85.
It's well-known that obesity affects the hormone levels in your body, and some of these hormones control the blood volume of your body, and also its sodium and water retention. Since they are important factors in the control of blood pressure, obesity is directly linked to it.
Again, the major thing you should do to reduce your blood pressure if you are overweight is lose weight. Other things that helps are:
- Exercise
- Lower your intake of salt
- Control stress
- Make sure you have enough potassium, magnesium and calcium in your diet.
Strength and Muscle Mass
As we saw earlier, when you gain body fat, you tend to lose muscle. This occurs naturally as you age, and also when you diet. You may lose weight when you diet, but much of it is muscle; furthermore, a relatively large fraction can also come from loss of water. So if you lose muscle you also lose strength. Loss of both muscle and strength is particularly bad for obese people. As we saw earlier, muscle is active and uses up calories at a high rate and keeps your metabolism high. In addition, strength is needed to support your weight and this can eventually lead to serious problems.
Exercise and diet are the key, but exercise - particularly aerobic exercise - is difficult for obese people because of their shortness of breath. Because of this it is best for them to begin with lifting light weights, and gradually increasing to heavier ones. Aerobic exercise (which uses up calories at a higher rate) can be introduced when they get in better shape.
Bone Density
Not only do their muscles decrease, but their bones also weaken as people gain weight. Most obese people have weaker, more brittle, bones than people of normal weight.
It's well-known that increasing your calcium intake can help. But it's also important to decrease your weight if you want to optimize your bone density. Again, exercise is critical for keeping your bones strong. Weight-bearing exercises such as walking, running and cycling are particularly good.
To sum up, if you are overweight (particularly if you are obese) and want to maximize your basic health markers you should:
- Eat more vegetables, fruit, grains and legumes
- Exercise more (preferably 30 minutes a day)
- Keep stress to a minimum
- Get adequate sleep
Barry Parker, Ph. D., is a professor emeritus (physics) at Idaho State University. He is the author of 26 books on science, health, writing, and music. His website is http://www.BarryParkerbooks.com and he has several blogs, one of them is at Barrysbuzz123.blogspot.com. He has done research in biophysics (mutations in the DNA molecule) and in relativity theory (Einstein's field theory), has a strong interest in health and fitness, self-improvement, and in music (particularly piano). He taught a writing class at ISU for several years. One of his recent books is "Feel Great Feel Alive." His latest book is "Learn from Yesterday, Live for Today, Hope for Tomorrow."
Article Source: http://EzineArticles.com/?expert=Barry_R_Parker
No comments:
Post a Comment