obese
Meaning of obese: A label drawn from a height and weight calculation rather than a description of a person, which is why person first wording is now preferred.
Definition of obese
Obese is an adjective describing a level of body fat high enough to be classified beyond the healthy range and to carry a raised chance of other conditions. It is a category rather than a diagnosis of any particular cause, and it is usually assigned from body mass index, a calculation using height and weight, alongside the rest of a clinical assessment.
How is the category assigned?
Body mass index is the usual starting point. It divides weight by the square of height and produces a single figure that sorts adults into underweight, healthy weight, overweight and obese bands, with the obese band split further into numbered classes by degree. The thresholds are not universal. Several countries and health bodies apply lower cutoffs for people of South Asian, Chinese and some other ancestries, because the risk of diabetes and heart disease climbs at a lower index in those groups. Children are handled differently again, through growth charts that compare a child with others of the same age and sex rather than against a fixed number.
What does body mass index miss?
Two things. It cannot separate fat from anything else, so a heavily muscled athlete can land in the obese band carrying very little fat, while an older person who has lost muscle can sit in the healthy band carrying a great deal. And it says nothing about where the fat sits. Fat packed around the organs inside the abdomen tracks far more closely with metabolic and cardiovascular risk than fat stored under the skin of the hips and thighs.
| Measure | What it captures | What it cannot show |
|---|---|---|
| Body mass index | Weight relative to height, in bands | Fat against muscle, and where fat is stored |
| Waist measurement | Fat around the abdominal organs | Total body fat |
| Body composition scan | Fat, muscle and bone separately | Little; used mainly in research because of cost |
Why has the wording changed?
Calling a person obese attaches a measurement to their identity. Many professional bodies and style guides have moved to person first phrasing instead, describing a person with obesity or a person living with obesity. The change is not cosmetic. Weight stigma inside healthcare is well documented, and it is associated with people delaying or avoiding appointments, which then affects conditions that have nothing to do with weight. The classification itself is still needed in the record, so the shift concerns how it is expressed rather than whether it is used.
Does the label explain the cause?
No. Excess body fat arises from a mixture of genetic inheritance, the biology of appetite and energy use, sleep, medicines, hormonal conditions, income, food availability and physical surroundings, and the mixture differs between individuals. Several widely prescribed medicines cause weight gain as a recognized effect, and a small number of endocrine conditions do the same. The word records where a measurement fell. It carries no information about why it fell there.
Used in a sentence
The patient's body mass index placed him in the obese range at the time of the visit.
Good to know
Obese is a classification derived mainly from body mass index rather than a diagnosis of an underlying cause, and two people placed in the same band can differ widely in body composition, fat distribution and overall health.
Word origin
Where “obese” comes from
From Latin obesus, meaning having eaten to excess, formed from ob- (over) and edere (to eat).