Why are BMIs useful ?

Why are BMIs useful?

It is the BMI measures an inexpensive and simple screening device employed to spot potential weight problems for both adults and children. It is a BMI assessment is beneficial in determining whether someone requires further tests to detect risk factors for heart disease. People who are at risk require further assessment. Assessments may include skin fold thickness test, diet, physical activity level, family history , and other health screenings that are appropriate for the individual.

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Risks related to BMIs that are extreme

Being either overweight (with an BMI that is 25 or higher) or in the weight range of underweight (with an BMI less than 18.5) can have a negative impact on your health.

Overweight

People who are overweight and obese are at a higher chance of developing diseases than people who are in those who are in the normal weight range. The risk of contracting disease increases as one increases BMI. Overweight people (BMI 25-29.9) can also be considered obese and more likely to develop developing disease. In the category 1 of obesity (BMI 30-34.9) the risk of developing a mild chance of illness, and this risk rises to severe and very severe risk in the stages of obesity 2 (BMI 35-39.9) in 3 (BMI greater than 40) respectively.

It is vital to understand that BMI doesn't determine risk on its own. Other variables like the type of food is consumed, how often they exercise, and the presence of any disease history within their family can affect the risk of developing diseases for an individual. As a group, overweight and obese individuals have a higher risk of numerous diseases.

They are at a significantly increased likelihood of:

• Type 2 Diabetes;
• Gall bladder disease
• Hypertension;
• Dyslipidaemia;
• Insulin Resistance;
• Atherosclerosis;
• Sleep apnoea;
• Breathlessness
• Asthma;
• Depression and social isolation.
• Daytime sleepiness and fatigue.

They are moderately at risk possibility of:

• Cardiovascular disorders (i.e. stroke, heart attack);
• Gout /hyperuricaemia;
• Osteoarthritis;
• Respiratory diseases;
• Hernia;
• Psychological issues.

They are at a slightly higher chance of:

• Some types of cancer (breast colon, endometrial and breast cancers);
• Reproductive disorders;
• Infertility impairment;
• Polycystic-ovarian syndrome
• Skin complications;
• Cataract;
• Varicose veins;
• Musculoskeletal disorders;
• Bad back
• Stress incontinence;
• Oedema/cellulitis.

Underweight

Underweight people may be undernourished. In addition they have an increased chance of developing health problems including:

• Imperfection in the immune system and increased susceptibility to infections;
• Anaemia;
• Osteoporosis;
• Menstrual irregularities;
• Infertility issues.

What do you think are the limits of BMI?

Limitations related to BMI. BMI are:

• BMI can vary based on age sexuality and race. Thus, one's BMI can only be compared to that of the same gender, age and race.
• BMI doesn't distinguish between muscle and fat and can therefore underestimate in some and overestimate for others (e.g. A person who is an athlete could have an elevated BMI because of a greater percentage of muscle than fat).
• The elderly or disabled are less muscular and consequently will have a lower BMI. It does not mean that their weight is not normal or even underweight.
• Women who are pregnant will also have a higher BMI due to increased weight that is associated with pregnancy, however, not necessarily due to increased fat. BMI is a way to overestimate body fat in this situation. Pregnancy BMI and weight gain during pregnancy should be used to assess a woman's weight and the necessity of exercise and nutritional interventions.
• BMI doesn't distinguish between the body's fat distribution. Fat around the waist ("apple" figure) is more risky than that around the hips ("pear" body shape) However, this risk will not be picked up in the BMI.

Check with your healthcare provider for additional physical measures that might require to be utilized together with BMI in order to evaluate health risks due to weight gain.

Other measures of overweight

Table 2: Other measures of obesity

Measure	Description
Waist circumference	Waist circumference (WC) is a good indicator of abdominal fat and can be used to identify the risk of health problems. It is determined by placing the tape that is not stretched around the narrowest level of your waist over light or no clothing.For men:>94 cm (37 inch) Risk increase to 102 cm (40 inch) - substantially increased riskFor women: > 80 cm ( 31 inches) greater risk 80 cm (31 inch) - increased risk> 88cm (35 inch) A significantly higher risk also varies based on ethnicity and health risk are higher with a lower WC within certain ethnic groups such as Aboriginal, Pacific Islander, South Asian, Chinese and Japanese populations.
Hip circumference	The hip circumference (HC) is measured by placing a tape on the widest portion of your thighs, and wearing the top of your clothing. HC is not a useful measurement in its own right; generally it is used to calculate an equivalent ratio to WC as mentioned above.
Waist-hip ratio	Waist to hip ratio (WHR) is the ratio of your waist circumference to your hip circumference. For females , the standard WHR is approximately 0.80 For men, it's 0.95.
Waist-height ratio	The ratio between waist and height is the ratio of the circumference of your waist in relation to your height.

More details

For more details on nutrition, such as information on kinds and composition of foods along with nutrition and individuals with health issues as well as diets and recipes and some useful tools and videos check out Nutrition.

For more information on the social and health effects of obesity as well as other issues related to it, as well as methods for losing weight, and other useful methods, refer to How to Lose Weight.

References

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