Obesity is a huge problem that affects many people these days. Faulty eating habits, lifestyle and lack of exercise are reasons that can lead to tremendous weight gain and resultant health problems. There are many simple non-invasive methods by which you can determine whether you are obese or not. These tests will help you identify the cause of your obesity and take necessary steps to correct the problem. The tests might have to be repeated in order to assess the progress of the treatment and also to check if the weight loss has been adequate. The main diagnostic tests used for checking whether you are obese are genetic testing, physical examination, blood tests, BMI, skin fold test, water displacement test, magnetic resonance imaging, waist circumference measurement, dual emission X ray Absorptiometry, Bioelectrical Impedence Analysis, Air Displacement Plethysmography etc.
Top diagnostic tests
1. Physical examination
A physical examination is a necessary part of one’s health checkup, at least once a year. During a physical examination, your doctor will be able to assess your body weight and check if there are any underlying health problems that are causing the weight gain. The doctor might also suggest doing some physical exercise and food control if you are obese and need to lose weight for health reasons. A basic physical examination is essential for checking all the body function and assessing your blood pressure, heart and lung function and also checking your family and medical history. A detailed analysis of the conditions that you suffer from and medications that you take too has to be given to the doctor to assess if some medications too are causing your obesity.
2. Genetic Testing
Genetic testing is aimed at those people who are suspected to have a genetic disposition towards obesity. This type of obesity is inherited and involves more than one gene. Hereditary obesity can be of different types. Cohen syndrome, which is an inherited obese condition, involves an anomaly caused by a single gene. Prader Willi Syndrome is another similar condition involving a single gene. These conditions and certain other obese conditions that involve mutations like that of melanocortin 4 receptor gene and obesity caused by leptin receptor or leptin deficiency crop up as obesity during childhood itself. These conditions are caused due to single variations in genes, called single nucleotide polymorphisms(SNP). Genetic testing can identify around eleven SNP obesity. Treatment methods are not very competent in genetic obesity as a number of genetic factors are involved and causes are unknown.
3. Blood Tests
Undergoing single blood test will not only help you assess your weight, but will also reveal if you are at risk of several conditions like cardiovascular diseases, diabetes, high blood pressure, cholesterol, liver diseases etc. All these diseases are directly linked to obesity and excess fat in your body. Blood tests can also detect thyroid disorders, which cause irregular metabolic functions and lead to obesity. Therefore, undergoing a blood test will help in getting adequate treatment on time and preventing obesity to a certain extent as well. Several blood tests might be necessary to assess what is the reason behind your obesity and also to check the progress during the course of the treatment.
4. BMI
BMI or body mass index is a test that determines whether your weight is in compliance with your height. BMI is calculated by checking your height and weight and dividing the weight in kilogram by the height in meters. A body mass index of 25-29.9 is considered to be overweight. A BMI that is above 30 is considered to be obese and not at all advisable. Checking your BMI helps you to also assess your susceptibility to certain conditions and diseases and take adequate measures to prevent the onset of such diseases. For calculating your BMI, one need not visit a doctor. It can be calculated at home and there are several websites as well which have BMI calculators for free.
5. Skin Fold Test
Skin fold test is a simple and cheap procedure that measures the fat under the skin to check the degree of obesity in a person. The advantage of taking a skin fold test lies in the fact that most of the fat that is deposited in a person’s body lies under the skin. However, the procedure is prone to many errors and is also not recommended for people who are very obese as the skin cannot be pinched adequately for conducting the test properly. Up to nine sites are identified for conducting a skin fold test. The procedure involves raising the two layers of the skin and adipose tissue by pinching, taking care not to pinch the muscle and measuring the skin thickness by inserting a calipers one centimeters below the pinch. The procedure has to be repeated at least twice and the average taken for best results.
6. Water Displacement Test
Water displacement method is a much more accurate method of calculating the body fat of a person. The technique is based on the theory of displacement of Archimedes. As fat is less dense than muscles and bone we weigh less under water than a muscle and bone of the same volume outside water. One can compare the difference in weight in land and water and assess the body fat accurately. Water displacement test requires specialized equipments and trained personnel for accurate readings. It also has a better accuracy with only a chance of variation of plus or minus 1.5 percent. However, this could be a cumbersome test when you have to assess your body fat several times during the treatment course.
7. Magnetic Resonance Imaging
Magnetic Resonance Imaging or MRI is a popular method of scanning the body for identifying a number of diseases and disorders. It is also known to be a very accurate measurement method for body fat as well. MRI scans can generate three-dimensional images of the body tissue and fat, which can be assessed separately, and a computer program is used for calculating the body fat percentage of the person undergoing the scan. Magnetic resonance imaging might be an expensive procedure, but it is very competent and can also show the location where the fat is deposited in the body. This is crucial in identifying the risk factors associated with fat deposits in certain parts of the body.
8. Dual Emission X Ray Absorptiometry
This is a procedure that is generally used for calculating the bone mineral density of a person. However, it can also be used for assessing the body fat percentage accurately. For measuring body fat mass, it first measures body cell mass and lean soft tissue and substracts it from either of them. However, the procedure may not be best suited when a person has to undergo several tests all throughout the treatment course as the radiation exposure would be high.
9. Bioelectrical Impedence Analysis
This method is one of the least invasive procedures for measuring body fat percentage. In this procedure, low levels of electric current are used for identifying the body fat percentage. Electrical current is released into the body and the body’s resistance to the electric current measured. If the resistance is high, it means that your body fat percentage too is high. Several bioelectrical impedence machines like weighing scales with footplates that pass electricity, electrodes that can be held in the hand and feet etc. are available for diagnosis. However, the accuracy of such machines can be a problem as fluctuation in hydration levels can greatly change the readings.
10. Air Displacement Plethysmography
Air Displacement Plethysmography is most commonly done using a Bod Pod, which is an apparatus that has an egg shape and is used for measuring the total density of the body. The procedure works on the principle that lean tissue is much more dense than fat tissue. This means that the more dense your body is, the leaner you are. One the density of the body is calculated, the Siri Equation is used for calculating the body fat percentage, i.e percent fat = (495/density) – 450. The procedure is very simple and all you need to do is to wear form-fitting clothes, covering your head with a cap, and sit in the chamber for about 5 minutes.
11. Waist Circumference Measurement
Waist circumference measurement is s simple procedure that can be done by anybody at home or at a doctor’s office. Abdominal fat is the cause for a number of ailments of the body like heart diseases, diabetes etc. Therefore, it is important to check for fat deposits in this area to assess your overall health condition and susceptibility to many diseases. A simple measuring tape can be used for measuring the waist circumference accurately. For women a waist circumference of above 35 inches and for men a circumference of above 40 inches are considered dangerous and can lead to health problems later on. A waist to hip ration too can help assess one’s risk of health problems later in life. A waist to hip ratio of more than 1 in men and .85 in women is categorized as obese.
