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{{Infobox medical condition
__NOTOC__
| Name          = Osteomalacia (rickets)
{{SI}}
| Image          =
{{CMG}}
| Caption        =
|Field          = [[Endocrinology]]
| DiseasesDB    = 9351
| ICD10          = {{ICD10|M|83||m|80}}
| ICD9          = {{ICD9|268.2}}
| ICDO          =
| OMIM          =
| MedlinePlus    = 000376
| eMedicineSubj  = ped
| eMedicineTopic = 2014
| eMedicine_mult = {{eMedicine2|radio|610}}
| MeshName      =
| MeshNumber    =
| MeshID        = D010018
}}
'''Osteomalacia''' is the softening of the [[bone]]s caused by deactivated [[bone mineralization]] primarily due to inadequate levels of available [[phosphate]] and [[calcium]], or because of [[bone resorption|resorption]] of calcium. Osteomalacia in children is known as [[rickets]], and because of this, use of the term "osteomalacia" is often restricted to the milder, adult form of the disease. Signs and symptoms can include diffuse body pains, muscle weakness, and fragility of the bones.


The most common cause of osteomalacia is a deficiency of [[vitamin D]], which is normally derived from sunlight exposure and, to a lesser extent, from the diet.<ref>[https://www.nlm.nih.gov/medlineplus/ency/article/000376.htm MedlinePlus Medical Encyclopedia: Osteomalacia<!-- Bot generated title -->]</ref> The most specific screening test for [[vitamin D deficiency]] in otherwise healthy individuals is a serum 25(OH)D level.<ref>{{cite book|last1=Longo|first1=Dan L.|title=Harrison's principles of internal medicine.|date=2012|publisher=McGraw-Hill|location=New York|isbn=978-0-07174889-6|edition=18th|display-authors=etal}}</ref> Less common causes of osteomalacia can include hereditary deficiencies of vitamin D or phosphate (which would typically be identified in childhood) or malignancy.
==Overview==
The term '''overweight''' is generally used to indicate that a [[human]] has more [[body fat]] than is considered useful for the optimal functioning of the body. Being overweight is a fairly common condition for many people, especially those in developed nations where food supplies are plentiful and lifestyles often do not involve a lot of activities that generate caloric expenditure. Recent studies have indicated that as much as 64% of the adult US population is overweight, and this number is increasing.<ref>{{cite journal | author=Katherine M. Flegal, PhD; Margaret D. Carroll, MS; Cynthia L. Ogden, PhD; Clifford L. Johnson, MSPH | title=Prevalence and Trends in Obesity Among US Adults, 1999-2000 | journal=[[Journal of the American Medical Association|JAMA]] | year=2002 | volume=288 | issue=14 | pages=1723&ndash;1727 | url=http://jama.ama-assn.org/cgi/content/full/288/14/1723  | id=PMID 12365955}}.</ref> A series of graphics from the CDC also describes the obesity prevalence trends in the U.S. in the past 2 decades: [http://www.epidemiologic.org/2006/10/obesity-epidemic-us-temporal-trends.html Obesity Epidemic: U.S. Temporal Trends 1985-2004]


Measures to prevent and treat osteomalacia usually revolve around intake of vitamin D and [[calcium|calcium supplements]]. Vitamin D should always be administered in conjunction with calcium supplementation since most of the consequences of vitamin D deficiency are a result of impaired mineral ion homeostasis.<ref>{{cite book|last1=Longo|first1=Dan L.|title=Harrison's principles of internal medicine.|date=2012|publisher=McGraw-Hill|location=New York|isbn=978-0-07174889-6|edition=18th|display-authors=etal}}</ref>
A healthy body requires a minimum amount of fat for the proper functioning of the hormonal, reproductive, and immune systems, as [[thermal insulation]], as [[shock absorber|shock absorption]] for sensitive areas, and as excess energy for future use. But the accumulation of too much storage fat can impair movement and flexibility, and can alter the appearance of the body.
== Classification ==
The degree to which a person is overweight is generally described using an indication of the amount of excess body fat present.  There are several common ways to measure the amount of fat present in an individual's body.(See also [[body fat percentage]]):
* '''[[weighing scale|Simple Weighing]]:''' The weight of the individual is measured and compared to an estimated ideal weight.  This is the easiest and most common method, but by far the least accurate, as it only measures one quantity (weight) and often does not take into account many factors such as height, body type, and relative amount of muscle mass.
* '''[[Body Mass Index]] (BMI):'''  This is an adaptation of simple weighing which attempts to take into account the subject's general body size by dividing the weight by the height squared (the units for BMI are kg/m<sup>2</sup>, but are rarely referenced, and BMI numbers are typically written and used as unitless numbers).  This provides a slightly more accurate representation than simply measuring raw weight, but still ignores many factors which can affect the results, and is generally not accurate for many individuals. 
* '''Skinfold [[Calipers]] or "pinch test":'''  With this method, the skin at several specific points on the body is pinched and the thickness of the resulting fold is measured.  This measures the thickness of the layers of fat located under the skin, from which a general measurement of total amount of fat in the body is calculated.  This method can be reasonably accurate for many people, but it does assume particular patterns for fat distribution over the body which may not apply to all individuals, and does not account for fat deposits which may not be directly under the skin.  Also, as the measurement and analysis generally involves a high degree of practice and interpretation, for an accurate result it must be performed by a professional and cannot generally be done by patients themselves.
* '''[[Bioelectrical impedance analysis]]:'''  This method involves passing a small electrical current through the body and measuring the body's resistance to the electrical flow. As fat and muscle conduct electricity differently, this method can provide a direct measurement of the percentage of body fat present as compared to muscle mass.  In the past, this technique could only be performed reliably by trained professionals with specialized equipment, but it is now possible to buy "home kits" which allow individuals to do this themselves with a minimum of training.  Despite the improved simplicity of this process over the years, however, there are a number of factors which can affect the results, including hydration and body temperature, so a fair amount of care must still be taken when applying this test to ensure that the results are in fact accurate and applicable.
* '''[[hydrostatic equilibrium|Hydrostatic]] Weighing:''' Considered one of the more accurate methods of measuring body fat, this technique involves completely submerging the subject underwater and using special equipment to measure his or her weight while submerged.  This weight is then compared with "dry weight" as recorded outside the water to determine overall body density.  As fat is less dense than muscle, careful application of this technique can provide a reasonably close estimate of fat content in the body.  This technique does, however, require expensive specialized equipment and trained professionals to administer it properly.
* '''[[DEXA]] (dual energy X-ray absorptiometry):''' Originally developed to measure bone density, DEXA imaging has also come to be used as a precise way to determine body fat content by using the density of various body tissues to identify which portions of the body are fat.  This test is generally considered to be very accurate, but requires a great deal of expensive medical equipment and trained professionals to perform.


Nursing home residents and the homebound elderly population are at particular risk for vitamin D deficiency, as these populations typically receive little sun exposure. In addition, both the efficiency of vitamin D synthesis in the skin and the absorption of vitamin D from the intestine decline with age, thus further increasing the risk in these populations. Other groups at risk include individuals with malabsorption secondary to gastrointestinal bypass surgery or celiac disease, and individuals who immigrate from warm climates to cold climates, especially women who wear traditional veils or dresses that prevent sun exposure.<ref>{{cite journal|last1=Kennel|first1=KA|last2=Drake|first2=MT|last3=Hurley|first3=DL|title=Vitamin D deficiency in adults: when to test and how to treat.|journal=Mayo Clinic Proceedings|date=August 2010|volume=85|issue=8|pages=752-7; quiz 757-8|pmid=20675513|doi=10.4065/mcp.2010.0138}}</ref>
Despite the inherent inaccuracies, the most common method for discussing this subject used by researchers and advisory institutions is [[body mass index]] (BMI) numbers.  Definitions of what is considered to be overweight change from time to time and sometimes from country to country, but the current definition proposed by both the US [[National Institutes of Health]] and the [[World Health Organization]] designates anyone with a BMI of 25 kg/m<sup>2</sup> or more to be overweight.


==Signs and symptoms==
BMI, however, does not account for differing amounts of [[muscle]] mass, [[genetics|genetic]] factors, or many other individual variations, and thus many individuals can have BMIs less than 25 and still be considered overweight, while others may have BMIs significantly higher without falling into this category<ref>{{cite journal | author=Dympna Gallagher, Steven B Heymsfield, Moonseong Heo, Susan A Jebb, Peter R Murgatroyd and Yoichi Sakamoto | title= Healthy percentage body fat ranges: an approach for developing guidelines based on body mass index | journal=[[AJCN]] | year=2000 | volume=72 | issue=3 | pages=694&ndash;701 | url=http://www.ajcn.org/cgi/content/full/72/3/694  | id=PMID 10966886}}.</ref>. Many of the more accurate methods mentioned above for determining body fat content can provide better indications of whether a particular individual is overweight or not.
Osteomalacia is a generalized bone condition in which there is inadequate mineralization of the bone. Many of the effects of the disease overlap with the more common [[osteoporosis]], but the two diseases are significantly different.
There are two main causes of osteomalacia: (1) insufficient calcium absorption from the intestine because of lack of dietary calcium or a deficiency of, or resistance to, the action of vitamin D; and (2) phosphate deficiency caused by increased renal losses.


*Diffuse joint and [[bone pain]] (especially of spine, pelvis, and legs)
If an individual is sufficiently overweight that excess body fat could present substantial [[health]] risks, he or she is considered to be [[obese]].  It is possible for someone to be overweight without being obese (according to the NIH and WHO, a BMI between 25 and 30 is considered to be "overweight" but not "obese").  Again, the designation
*Muscle weakness
of "obesity" is subject to a great deal of interpretation and many individual factors, so an individual with a BMI well below 30 may be considered to be obese depending on their particular condition, while in some cases a BMI above 30 may not actually indicate obesity (although likely still does indicate being overweight).
*Difficulty walking, often with waddling gait
== Causes ==
*[[Hypocalcemia]] (positive [[Chvostek sign]])
*Compressed vertebrae and diminished stature
*Pelvic flattening
*Weak, soft bones
*Easy fracturing
*Bending of bones


Osteomalacia in adults starts insidiously as aches and pains in the [[lumbar]] (lower back) region and thighs before spreading to the arms and ribs. The pain is symmetrical, non-radiating and accompanied by sensitivity in the involved bones. Proximal muscles are weak, and there is difficulty in climbing up stairs and getting up from a [[squatting position]].
Being overweight is generally caused by the intake of more calories (by eating) than are expended by the body (by exercise and everyday living). Factors which may contribute to this imbalance include:


As a result of demineralization, the bones become less rigid. Physical signs include deformities like triradiate pelvis<ref>{{cite journal |last1=Chakravorty |first1=N. K. |title=Triradiate deformity of the pelvis in Paget's disease of bone. |journal=Postgraduate Medical Journal |volume=56 |issue=653 |pages=213–5 |year=1980 |pmid=7393817 |pmc=2425842 |doi=10.1136/pgmj.56.653.213}}</ref> and [[lordosis]]. The patient has a typical "waddling" gait. However, these physical signs may derive from a previous osteomalacial state, since bones do not regain their original shape after they become deformed.
* Limited exercise and sedentary lifestyle
* [[Overeating]]
* Poor nutrition
* [[genetics|Genetic]] predisposition
* Hormone imbalances (e.g. [[hypothyroidism]])
* Metabolic disorders, which could be caused by repeated attempts to lose weight by [[Yo-yo dieting|Weight cycling]],
* An [[eating disorder]] (such as [[binge eating disorder]])
* [[Alcoholism]]
* [[Stress (medicine)|Stress]]
* Insufficient [[sleep]]
* Psychotropic medications
* [[Smoking cessation]] and other [[stimulant]] withdrawal


Pathologic fractures due to weight bearing may develop. Most of the time, the only alleged symptom is [[fatigue (medical)#Chronic fatigue|chronic fatigue]], while bone aches are not spontaneous but only revealed by pressure or shocks.
The amount of body fat is regulated to some extent subconsciously by the brain (by controlling caloric intake through appetite and food preferences).  Although the exact mechanisms by which this occurs are not entirely known, one common theory suggests that each person may possess an inherent "set point" weight which the brain attempts to maintain, and that this set point may vary for each individual depending on a variety of factors including genetic predisposition, environment, and past experience.


It differs from renal [[osteodystrophy]], where the latter shows [[hyperphosphatemia]].
This leads to the conclusion that some individuals may be predisposed to naturally maintaining different body weights than others, and thus it may be easier for some people to avoid being overweight, while others may find it much more difficult.  It also suggests, however, that an individual's set point may be changeable with appropriate environment and conditioning.
== Health-related Implications ==
While the health issues associated with [[obesity]] are well accepted within the medical community, the health implications of the overweight category are more controversial. The generally accepted view has been that overweight often shares adverse risks with obesity, relative to normal weight. Adams et al. estimated that risk of death increases by 20 to 40 percent among overweight persons.<ref>{{cite journal | author=Kenneth F. Adams, Ph.D., Arthur Schatzkin, M.D., Tamara B. Harris, M.D., Victor Kipnis, Ph.D., Traci Mouw, M.P.H., Rachel Ballard-Barbash, M.D., Albert Hollenbeck, Ph.D., and Michael F. Leitzmann, M.D. | title=Overweight, Obesity, and Mortality in a Large Prospective Cohort of Persons 50 to 71 Years Old | journal=[[NEJM]] |year=2006 | volume=355 | issue=8 | pages=763&ndash;788 | url=http://content.nejm.org/cgi/content/short/355/8/763?query=prevarrow}}</ref>


==Causes==
Flegal et al., however, found that mortality rates for individuals who are classified as overweight (BMI 25 to 30) may actually be lower than for those with an "ideal" weight (BMI 18.5 to 25)<ref>{{cite journal | author=Katherine M. Flegal, PhD; Barry I. Graubard, PhD; David F. Williamson, PhD; Mitchell H. Gail, MD, PhD | title=Excess Deaths Associated With Underweight, Overweight, and Obesity | journal=[[Journal of the American Medical Association|JAMA]] | year=2005 | volume=293 | issue=15 | pages=1861&ndash;1867 | url=http://jama.ama-assn.org/cgi/content/abstract/293/15/1861 |id=PMID 15840860}}.</ref>. 
The causes of adult osteomalacia are varied, but ultimately result in a vitamin D deficiency:


*Insufficient nutritional quantities or faulty metabolism of [[vitamin D]] or [[phosphorus]]
Psychological well-being is also at risk in the overweight individual.  Discrimination against fat persons is common socially and legally. This may affect their ability to find a mate or employment. The receipt of overt remarks from childhood into old age also shape the personality of the overweight individual, either making him/her more resolute and obstinate or too willing to please others.
*[[Renal tubular acidosis]]
*[[Malnutrition]] during [[pregnancy]]
*[[Malabsorption]] syndrome
*[[Hypophosphatemia]]<ref>{{cite web|url=http://mpkb.org/home/pathogenesis/vitamind|title=Autoimmunity research foundation, Science behind Vitamin D|accessdate=2011-07-19}}</ref>
*[[Chronic kidney failure]]
*[[Tumor-induced osteomalacia]]
*Long-term [[anticonvulsant]] therapy<ref>{{cite journal |last1=Pack |first1=Alison |title=Bone health in people with epilepsy: is it impaired and what are the risk factors |journal=Seizure |volume=17 |issue=2 |pages=181–6 |year=2008 |pmid=18187347 |doi=10.1016/j.seizure.2007.11.020}}</ref>
*[[Celiac disease]]<ref>{{cite journal |last1=Albany |first1=Costantine |last2=Servetnyk |first2=Zhanna |title=Disabling osteomalacia and myopathy as the only presenting features of celiac disease: a case report |journal=Cases Journal |volume=2 |issue=1 |pages=20 |year=2009 |pmid=19128487 |pmc=2626577 |doi=10.1186/1757-1626-2-20}}</ref>
*[[Cadmium poisoning]], [[Itai-itai disease]]


==Diagnosis==
== Treatment ==
===Medical Therapy===
A large number of people undergo some form of treatment to attempt to reduce their weight, usually either in an attempt to improve their health, to improve their lifestyle, or for cosmetic reasons.  The generally recommended treatment for being overweight is a [[dieting|modified or controlled diet]] in conjunction with increased [[exercise]]. For those who are obese rather than overweight, more intensive therapies such as drugs or surgery are sometimes used (see [[Obesity]]).


===Biochemical findings===
Studies suggest that reducing calorie intake by itself (dieting) may have short-term effects but does not lead to long-term weight loss, and can often result in gaining back all of the lost weight and more in the longer term. For this reason, it is generally recommended that weight-loss diets not be attempted on their own but instead in combination with increased exercise and long-term planning and weight management.


Biochemical features are similar to those of [[rickets]]. The major factor is an abnormally low vitamin D concentration in blood serum.
The health benefits of weight loss are also somewhat unclear.  While it is generally accepted that for significantly obese patients, losing weight can reduce health risks and improve quality of life, there is some evidence to suggest that for merely overweight patients, the health effects of attempting to lose weight may actually be more detrimental than simply remaining overweight<ref>{{cite journal | author=Sørensen TI, Rissanen A, Korkeila M, Kaprio J. | title=Intention to Lose Weight, Weight Changes, and 18-y Mortality in Overweight Individuals without Co-Morbidities. | journal=[[PLoS]] | year=2005 | volume=2 | issue=6 | pages=e171 | url=http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.0020171  | id=PMID 15971946}}.</ref>.  Moreover, for all individuals, repeatedly losing weight and then gaining it back ("[[yo-yo dieting]]"), is believed to do more harm than good and can be the cause of significant additional health problems. This is caused by the loss of more muscle than fat.


Major typical biochemical findings include:<ref>{{cite journal|last1=Holick|first1=Michael F.|title=Vitamin D Deficiency|journal=New England Journal of Medicine|date=19 July 2007|volume=357|issue=3|pages=266–281|doi=10.1056/NEJMra070553|pmid=17634462}}</ref>
There is no healthy, short-term solution for solving obesity, or being overweight. Changes in lifestyle, such as more exercise or dieting, must be permanent changes.
*Low serum and urinary calcium
*Low serum phosphate, except in cases of [[renal osteodystrophy]]
*Elevated serum [[alkaline phosphatase]] (due to an increase in compensatory [[osteoblast]] activity)
*Elevated [[parathyroid hormone]] (due to low calcium)


Furthermore, a [[technetium]] bone scan will show increased activity (also due to increased osteoblasts).
== References ==
{{reflist|2}}


{{Bone pathology}}


===Radiographic characteristics===
[[Category:Health risks]]
[[Category:Nutrition]]
[[Category:body shape]]
[[Category:primary care]]


Radiological appearances include:
[[ar:بدانة]]
 
[[da:Overvægt]]
*[[Pseudofracture]]s, also called Looser's zones.
[[de:Übergewicht]]
*[[Protrusio acetabuli]], a hip joint disorder
[[es:Sobrepeso]]
 
[[it:Sovrappeso]]
==Treatment==
[[pl:Nadwaga]]
Nutritional osteomalacia responds well to administration of 10,000&nbsp;[[International Unit|IU]] weekly of vitamin D for four to six weeks. Osteomalacia due to malabsorption may require treatment by injection or daily oral dosing<ref>{{cite journal |last1=Eisman |first1=John A. |title=6 Osteomalacia |journal=Baillière's Clinical Endocrinology and Metabolism |volume=2 |pages=125–55 |year=1988 |doi=10.1016/S0950-351X(88)80011-9}}</ref> of significant amounts of vitamin D.
{{WikiDoc Help Menu}}
 
{{WikiDoc Sources}}
==Etymology==
Osteomalacia is derived from Greek: ''osteo-'' which means "bone", and ''malacia'' which means "softness". In the past, the disease was also known as '''malacosteon''' and its Latin-derived equivalent, '''mollities ossium'''.
Osteomalacia is associated with increase in osteoid maturation time.
 
==References==
{{reflist}}
 
==See also==
*[[Osteopetrosis]], the opposite of osteomalacia
 
{{Nutritional pathology}}
{{Osteochondropathy}}
 
[[Category:Pediatrics]]
[[Category:Osteopathies]]
[[Category:Vitamin D]]

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

The term overweight is generally used to indicate that a human has more body fat than is considered useful for the optimal functioning of the body. Being overweight is a fairly common condition for many people, especially those in developed nations where food supplies are plentiful and lifestyles often do not involve a lot of activities that generate caloric expenditure. Recent studies have indicated that as much as 64% of the adult US population is overweight, and this number is increasing.[1] A series of graphics from the CDC also describes the obesity prevalence trends in the U.S. in the past 2 decades: Obesity Epidemic: U.S. Temporal Trends 1985-2004

A healthy body requires a minimum amount of fat for the proper functioning of the hormonal, reproductive, and immune systems, as thermal insulation, as shock absorption for sensitive areas, and as excess energy for future use. But the accumulation of too much storage fat can impair movement and flexibility, and can alter the appearance of the body.

Classification

The degree to which a person is overweight is generally described using an indication of the amount of excess body fat present. There are several common ways to measure the amount of fat present in an individual's body.(See also body fat percentage):

  • Simple Weighing: The weight of the individual is measured and compared to an estimated ideal weight. This is the easiest and most common method, but by far the least accurate, as it only measures one quantity (weight) and often does not take into account many factors such as height, body type, and relative amount of muscle mass.
  • Body Mass Index (BMI): This is an adaptation of simple weighing which attempts to take into account the subject's general body size by dividing the weight by the height squared (the units for BMI are kg/m2, but are rarely referenced, and BMI numbers are typically written and used as unitless numbers). This provides a slightly more accurate representation than simply measuring raw weight, but still ignores many factors which can affect the results, and is generally not accurate for many individuals.
  • Skinfold Calipers or "pinch test": With this method, the skin at several specific points on the body is pinched and the thickness of the resulting fold is measured. This measures the thickness of the layers of fat located under the skin, from which a general measurement of total amount of fat in the body is calculated. This method can be reasonably accurate for many people, but it does assume particular patterns for fat distribution over the body which may not apply to all individuals, and does not account for fat deposits which may not be directly under the skin. Also, as the measurement and analysis generally involves a high degree of practice and interpretation, for an accurate result it must be performed by a professional and cannot generally be done by patients themselves.
  • Bioelectrical impedance analysis: This method involves passing a small electrical current through the body and measuring the body's resistance to the electrical flow. As fat and muscle conduct electricity differently, this method can provide a direct measurement of the percentage of body fat present as compared to muscle mass. In the past, this technique could only be performed reliably by trained professionals with specialized equipment, but it is now possible to buy "home kits" which allow individuals to do this themselves with a minimum of training. Despite the improved simplicity of this process over the years, however, there are a number of factors which can affect the results, including hydration and body temperature, so a fair amount of care must still be taken when applying this test to ensure that the results are in fact accurate and applicable.
  • Hydrostatic Weighing: Considered one of the more accurate methods of measuring body fat, this technique involves completely submerging the subject underwater and using special equipment to measure his or her weight while submerged. This weight is then compared with "dry weight" as recorded outside the water to determine overall body density. As fat is less dense than muscle, careful application of this technique can provide a reasonably close estimate of fat content in the body. This technique does, however, require expensive specialized equipment and trained professionals to administer it properly.
  • DEXA (dual energy X-ray absorptiometry): Originally developed to measure bone density, DEXA imaging has also come to be used as a precise way to determine body fat content by using the density of various body tissues to identify which portions of the body are fat. This test is generally considered to be very accurate, but requires a great deal of expensive medical equipment and trained professionals to perform.

Despite the inherent inaccuracies, the most common method for discussing this subject used by researchers and advisory institutions is body mass index (BMI) numbers. Definitions of what is considered to be overweight change from time to time and sometimes from country to country, but the current definition proposed by both the US National Institutes of Health and the World Health Organization designates anyone with a BMI of 25 kg/m2 or more to be overweight.

BMI, however, does not account for differing amounts of muscle mass, genetic factors, or many other individual variations, and thus many individuals can have BMIs less than 25 and still be considered overweight, while others may have BMIs significantly higher without falling into this category[2]. Many of the more accurate methods mentioned above for determining body fat content can provide better indications of whether a particular individual is overweight or not.

If an individual is sufficiently overweight that excess body fat could present substantial health risks, he or she is considered to be obese. It is possible for someone to be overweight without being obese (according to the NIH and WHO, a BMI between 25 and 30 is considered to be "overweight" but not "obese"). Again, the designation of "obesity" is subject to a great deal of interpretation and many individual factors, so an individual with a BMI well below 30 may be considered to be obese depending on their particular condition, while in some cases a BMI above 30 may not actually indicate obesity (although likely still does indicate being overweight).

Causes

Being overweight is generally caused by the intake of more calories (by eating) than are expended by the body (by exercise and everyday living). Factors which may contribute to this imbalance include:

The amount of body fat is regulated to some extent subconsciously by the brain (by controlling caloric intake through appetite and food preferences). Although the exact mechanisms by which this occurs are not entirely known, one common theory suggests that each person may possess an inherent "set point" weight which the brain attempts to maintain, and that this set point may vary for each individual depending on a variety of factors including genetic predisposition, environment, and past experience.

This leads to the conclusion that some individuals may be predisposed to naturally maintaining different body weights than others, and thus it may be easier for some people to avoid being overweight, while others may find it much more difficult. It also suggests, however, that an individual's set point may be changeable with appropriate environment and conditioning.

Health-related Implications

While the health issues associated with obesity are well accepted within the medical community, the health implications of the overweight category are more controversial. The generally accepted view has been that overweight often shares adverse risks with obesity, relative to normal weight. Adams et al. estimated that risk of death increases by 20 to 40 percent among overweight persons.[3]

Flegal et al., however, found that mortality rates for individuals who are classified as overweight (BMI 25 to 30) may actually be lower than for those with an "ideal" weight (BMI 18.5 to 25)[4].

Psychological well-being is also at risk in the overweight individual. Discrimination against fat persons is common socially and legally. This may affect their ability to find a mate or employment. The receipt of overt remarks from childhood into old age also shape the personality of the overweight individual, either making him/her more resolute and obstinate or too willing to please others.

Treatment

Medical Therapy

A large number of people undergo some form of treatment to attempt to reduce their weight, usually either in an attempt to improve their health, to improve their lifestyle, or for cosmetic reasons. The generally recommended treatment for being overweight is a modified or controlled diet in conjunction with increased exercise. For those who are obese rather than overweight, more intensive therapies such as drugs or surgery are sometimes used (see Obesity).

Studies suggest that reducing calorie intake by itself (dieting) may have short-term effects but does not lead to long-term weight loss, and can often result in gaining back all of the lost weight and more in the longer term. For this reason, it is generally recommended that weight-loss diets not be attempted on their own but instead in combination with increased exercise and long-term planning and weight management.

The health benefits of weight loss are also somewhat unclear. While it is generally accepted that for significantly obese patients, losing weight can reduce health risks and improve quality of life, there is some evidence to suggest that for merely overweight patients, the health effects of attempting to lose weight may actually be more detrimental than simply remaining overweight[5]. Moreover, for all individuals, repeatedly losing weight and then gaining it back ("yo-yo dieting"), is believed to do more harm than good and can be the cause of significant additional health problems. This is caused by the loss of more muscle than fat.

There is no healthy, short-term solution for solving obesity, or being overweight. Changes in lifestyle, such as more exercise or dieting, must be permanent changes.

References

  1. ↑ Katherine M. Flegal, PhD; Margaret D. Carroll, MS; Cynthia L. Ogden, PhD; Clifford L. Johnson, MSPH (2002). "Prevalence and Trends in Obesity Among US Adults, 1999-2000". JAMA. 288 (14): 1723&ndash, 1727. PMID 12365955..
  2. ↑ Dympna Gallagher, Steven B Heymsfield, Moonseong Heo, Susan A Jebb, Peter R Murgatroyd and Yoichi Sakamoto (2000). "Healthy percentage body fat ranges: an approach for developing guidelines based on body mass index". AJCN. 72 (3): 694&ndash, 701. PMID 10966886..
  3. ↑ Kenneth F. Adams, Ph.D., Arthur Schatzkin, M.D., Tamara B. Harris, M.D., Victor Kipnis, Ph.D., Traci Mouw, M.P.H., Rachel Ballard-Barbash, M.D., Albert Hollenbeck, Ph.D., and Michael F. Leitzmann, M.D. (2006). "Overweight, Obesity, and Mortality in a Large Prospective Cohort of Persons 50 to 71 Years Old". NEJM. 355 (8): 763&ndash, 788.
  4. ↑ Katherine M. Flegal, PhD; Barry I. Graubard, PhD; David F. Williamson, PhD; Mitchell H. Gail, MD, PhD (2005). "Excess Deaths Associated With Underweight, Overweight, and Obesity". JAMA. 293 (15): 1861&ndash, 1867. PMID 15840860..
  5. ↑ Sørensen TI, Rissanen A, Korkeila M, Kaprio J. (2005). "Intention to Lose Weight, Weight Changes, and 18-y Mortality in Overweight Individuals without Co-Morbidities". PLoS. 2 (6): e171. PMID 15971946..

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