Why are BMIs useful ?

Why are BMIs useful?

The BMI BMI is an easy, low-cost screening tool for identifying potential overweight issues for adults as well as children. A BMI test can be important to determine who needs further tests to detect the risk of heart disease. The people who are at risk need more evaluation. Assessments may include tests for the thickness of skin folds and diet, as well as physical activity level, family history , and other necessary health screenings.

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Risks associated with extreme BMIs

Being either overweight (with a BMI of more than 25) or underweight (with an BMI less than 18.5) can have an impact on your health.

Overweight

Individuals who are overweight or obese are at greater risk of disease compared to those in an appropriate weight category. The risk of developing disease rises as one increases BMI. The people who are classified as overweight (BMI 25-29.9) could also be considered to be pre-obese, and are more likely to develop disease. In Category 1 obesity (BMI 30-34.9) There is moderate chance of illness, and this risk rises to severe or very severe risk at the stage of obesity 2 (BMI 35-39.9) in 3 (BMI >=40) and 3 (BMI >=40).

It is vital to understand that BMI does not indicate risk in and of itself. Other factors such as what one eats, how much they exercise, and whether or not there's any medical history in their family could affect the risk of developing diseases for an individual. However as a group the obese and overweight are at a higher risk of various diseases.

They have a greatly increased possibility of:

• Type 2 Diabetes;
• Gall bladder disease
• Hypertension;
• Dyslipidaemia;
• Insulin Resistance;
• Atherosclerosis;
• Sleep apnoea;
• Breathlessness
• Asthma;
• Social isolation and depression;
• The fatigue and sleepiness of the day.

They have a moderately increased likelihood of:

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

They are at a slightly higher possibility of:

• Some types of cancer (breast, colon and endometrial cancers);
• Reproductive abnormalities;
• Impaired fertility;
• Polycystic ovarian Syndrome;
• Skin issues;
• Cataract;
• Varicose veins;
• Musculoskeletal issues;
• Bad back
• Stress incontinence;
• Oedema/cellulitis.

Underweight

Individuals who are underweight may be undernourished. Additionally, they may be at an increased chance of developing health issues including:

• Immune function is compromised, resulting in increased susceptibility to infections
• Anaemia;
• Osteoporosis;
• Menstrual irregularities;
• Affected fertility.

What is the limit of the BMI?

Limitations associated with the BMI are:

• BMI varies by age, gender, and race. Thus, one's BMI can only be compared with that with the same sex age , and race.
• BMI doesn't distinguish between fat and muscle, and therefore will underestimate in some instances, while overestimating in others (e.g. An athlete could have a high BMI because of the higher amount of muscle and less fat).
• Older or disabled people have less muscle mass , and therefore , have an equivalence in BMI. This doesn't necessarily mean that their weight is healthy or not enough.
• The pregnant women may also be more obese BMI because of the increased weight due to pregnancy, but not always due to an increase in fat. BMI will underestimate the amount of fat in the body in this scenario. Pregnancy BMI and weight increase during pregnancy must be used to evaluate the woman's weight and determine the necessity of exercise and nutritional interventions.
• BMI does not differentiate between the body's fat distribution. The fat around the waist ("apple" appearance) is more hazardous than the hips ("pear" body shape) however, this is not reflected by the BMI.

See your healthcare provider for other physical measures that could be required together with BMI to assess health risks due to obesity.

Other indicators of the obesity

Table 2 Other ways to measure obesity

Measure	Description
Waist circumference	Waist circumference (WC) is an effective measure of abdominal fat, and can be used to indicate health risk. It's measured by placing an unstretched tape measure around the narrowest area of your waist. This is done over either light or none clothing.For men:>94 (37 inches) - increased risk> 102 cm (37 inch) Risk increase to 100 cm (40 inch) Risk significantly higher women:> 80cm ( 31 inches) - increased risk> 80 cm (31 inch) - increased risk> 88cm (35 inch) Risque also differs based on ethnicity and health risks are higher with a lower WC in certain ethnic groups like Aboriginal, Pacific Islander, South Asian, Chinese and Japanese populations.
Hip circumference	The hip circumference (HC) is determined using a tape that is placed around the widest area of your hip area over some clothing. HC is not a useful measurement on its own; usually it's used as a ratio with WC as above.
The ratio of hips to waist	Waist to hip ratio (WHR) is the ratio of your waist circumference to your hip circumference. The normal WHR for females is around 0.80 For men, it's 0.95.
Waist-height ratio	Waist to height ratio refers to the proportion of the circumference of your waist to your height.

More information

For more information on nutrition, including information on kinds and composition of foods, nutrition and people as well as conditions that relate to nutrition as well as diets and recipes along with useful videos and resources check out Nutrition.

For more information about the social and health effects of obesity as well as other issues related to it, as well as methods of weight loss, as well as a few useful methods, refer to the article Weight Loss.

References

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