Why are BMIs useful ?

Why are BMIs useful?

BMI is a BMI measures an inexpensive, simple screening device for identifying potential issues with weight for adults and children. It is a BMI measurement can be helpful in determining who requires further testing to identify dangers to health, like heart disease. People who are at risk require more assessment. Tests can include the thickness of the skin fold test as well as diet, physical activity levels, family history and other health screenings that are appropriate for the individual.

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Risks related to BMIs that are extreme

Being or overweight (with a BMI of 25 or more) or underweight (with an BMI less than 18.5) could affect your health.

Overweight

People who are obese or overweight obese are at a higher risk of getting sick than people who are in normal weight. The risk of contracting disease increases when you increase your BMI. The people who are classified as overweight (BMI 25-29.9) may also be considered to be pre-obese, and are at a higher risk of developing disease. In Category 1 obesity (BMI 30-34.9) the risk of developing a mild risk of illness, and this risk rises to severe and very severe risk at obesity stages 2 (BMI 35-39.9) in 3 (BMI greater than 40) and 3 (BMI >=40).

It is important to realize that BMI doesn't determine risk alone. Other factors like what people eat, how frequently they exercise and whether or not there is a history of disease within their families can also affect the likelihood of developing a disease. But as a group overweight and obese people have a higher risk of many diseases.

They are significantly at risk probability of

• Type 2 Diabetes;
• Gall bladder disease;
• Hypertension;
• Dyslipidaemia;
• Insulin Resistance;
• Atherosclerosis;
• Sleep apnoea
• Breathlessness
• Asthma;
• Depression and social isolation;
• A lack of sleep and fatigue during the day.

They are at a moderately higher chance of:

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

They are at a slightly higher risk of:

• Different types of cancer (breast, colon and endometrial cancers);
• Reproductive abnormalities;
• Low fertility;
• Polycystic-ovarian syndrome
• Skin problems;
• Cataract;
• Varicose veins;
• Musculskeletal problems;
• Bad back
• Stress incontinence;
• Oedema/cellulitis.

Underweight

In the event of being overweight, a person could be deficient in nutrition. In addition they have an increased chance of developing health conditions, such as:

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

What are the limitations of BMI?

Limitations as they relate to BMI are: BMI are:

• BMI is different based on age, sexuality and race. Thus, one's BMI cannot be compared with those who are of the same sex, age , and race.
• BMI does not distinguish between muscle and fat and therefore will underestimate in certain instances and overestimate for others (e.g. An athlete may have a high BMI because of greater amount of muscle than fat).
• The elderly or disabled are less muscular and consequently have lower BMI. This does not necessarily mean that their weight isn't normal or that they are overweight.
• The pregnant women may also have a higher BMI due to weight gain due to pregnancy, but it is not necessarily due to the increase in fat. BMI can underestimate the amount of body fat. Pregnancy BMI and weight increase during pregnancy should be used to determine the woman's weight and determine the need for exercise and nutritional interventions.
• BMI does not differentiate between the body's fat distribution. Fat on the abdomen ("apple" body shape) is more hazardous than hips ("pear" body shape) however this will not be picked up through the BMI.

See your healthcare provider for other physical measurements that may be required along with BMI to assess health risks related to obesity.

Other indicators of overweight

Table 2 Additional measures of obesity

Measure	Description
Waist circumference	Waist circumference (WC) is an effective measure of abdominal fat, and can be used to determine health risks. It is determined by placing an untretched tape around the narrowest portion of your waist over the top of your light or even no clothing.For men:> 94 centimeters (37 inch) Increased risk> 100 inches (40 inch) Significantly increased risk women:> 80 cm ( 31 inch) - increased risk> 80 cm (31 inch) - increased risk> 88cm (35 inch) Risk is significantly increased is also dependent on ethnicity and health risks are more pronounced with a lower WC in certain ethnicities, such as Aboriginal, Pacific Islander, South Asian, Chinese and Japanese populations.
The hip circumference	The hip circumference (HC) is measured by putting a tape around the widest area of your thighs, and wearing only a small amount of clothing. HC is not a useful measurement as a stand-alone measurement; instead, it is used as an inverse ratio to WC, as described previously mentioned.
Rapport between waist and hip	Waist to hip ratio (WHR) is the ratio of your waist circumference to your hip circumference. For females the normal WHR is around 0.80 and for males it is 0.95.
Waist-height ratio	Waist to height ratio refers to the ratio of the circumference of your waist in relation to your height.

More information

To learn more about nutrition, including information on the different types of food items and their composition along with nutrition and individuals, conditions related to nutrition such as diets and recipe as well as useful tools and videos check out Nutrition.

For more information about overweight, social health, and methods for losing weight, and other useful methods, refer to weight loss.

References

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