There are also different tiers of anorexia based on BMI ranging from mild (<17.5), moderate (16-16.99), and severe (15-15.99), to extreme (<15). A BMI below 13.5 can lead to organ failure, while a BMI below 12 can be life-threatening.
Mild/moderate Anorexia Nervosa is defined as an individual with a BMI of 15-17.5 where the condition is stable and there is a lower risk of rapid deterioration.
BMI. When guiding weight restoration, most eating disorder services use the BMI range of 20 – 25 as a minimum healthy weight.
End-stage anorexia nervosa is anorexia nervosa in its most dangerous and severe form. Those experiencing end-stage anorexia present as severely underweight with a BMI of less than 15, are suffering the physical and psychological effects of severe starvation, and require immediate life-saving medical interventions [2].
A BMI nearing 15 is usually used as an indicator for starvation and the health risks involved, with a BMI <17.5 being one of the DSM criteria for the diagnosis of anorexia nervosa.
A BMI <16.0 is known to be associated with a markedly increased risk for ill-health, poor physical performance, lethargy and even death; therefore, this cut-off point is a valid extreme limit.
under 18.5kg/m2 – you are considered underweight and possibly malnourished. 18.5 to 24.9kg/m2 – you are within a healthy weight range for young and middle-aged adults. 25.0 to 29.9kg/m2 – you are considered overweight. over 30kg/m2 – you are considered obese.
According to the DSM-5, BMI criteria for anorexia nervosa (AN) or “anorexia BMI” requires that someone have a BMI of less than 18.5.
In males, a BMI of around 13 appears to be fatal. The coefficient of variation (CV) of the BMI is 8.7%. In contrast, females survive to a lower BMI of around 11, although with greater index variability (CV 14%). Several females had BMI's as low as 9 and 10.
The American Dietetic Association (ADA) defines the ideal body mass index (BMI) as between 20 and 25. Thus, anyone below that range would be considered underweight and those with a BMI from 18.5 to 17.5 extremely underweight.
There are also different tiers of anorexia based on BMI ranging from mild (<17.5), moderate (16-16.99), and severe (15-15.99), to extreme (<15). A BMI below 13.5 can lead to organ failure, while a BMI below 12 can be life-threatening.
It is not uncommon for daily caloric needs of people recovering from anorexia to reach 3,000 to 5,000 daily calories for a sufficient 1/2 pound to 2 pounds per week weight gain until achieving goal weight. This is especially true for adolescents who are still growing and young adults.
for hospitalization:
BMI < 13 is an indicatior for certification under the Mental Health Act if the patient refuses admission although BMI < 13 alone is not enough for admission.
When looking at average BMI, three countries tie for the least obese country in the world, with an average BMI of 21.1: Madagascar, Eritrea, and Ethiopia. Five other countries have average BMIs under 22: Timor-Leste (21.3), Burundi (21.6), Japan (21.8), China (21.9) and India (21.9).
Anorexia nervosa may be mild and transient or severe and persistent. The first indications that someone is developing anorexia nervosa may be a subtle increased concern with diet and body weight in a person who is not significantly overweight.
If your BMI is less than 18.5, it falls within the underweight range. If your BMI is 18.5 to 24.9, it falls within the Healthy Weight range. If your BMI is 25.0 to 29.9, it falls within the overweight range.
Participants whose BMIs were between 40 and 49.9 were more than twice as likely to die during the study period than those whose BMI was in the optimal range of 22.5 to 24.9.
Compared to normal weight, underweight was associated with increased all-cause mortality (HR: 1.37; 95% CI: 1.14-1.65).
From a clinical perspective, an individual is considered “too skinny” if they are deemed underweight. According to the Centers for Disease Control, an individual is underweight if their Body Mass Index (BMI) is below 18.5 [1].
18 or lower: underweight. 18.5 to 24.9: normal, healthy weight. 25 to 29.9: overweight. 30 or higher: obese.
Anorexia Nervosa
BMI emerged as the most potent predictor: for participants in the upper 83% of BMI the incidence of AN onset was 0.3% versus 11.1% for participants in the lower 17% of BMI.
BMI <17.0: moderate and severe thinness. BMI <18.5: underweight. BMI 18.5–24.9: normal weight. BMI ≥25.0: overweight.
below 18.5 – you're in the underweight range. 18.5 to 24.9 – you're in the healthy weight range. 25 to 29.9 – you're in the overweight range. 30 to 39.9 – you're in the obese range.
A normal BMI for an adult is 18.5-25. Above that you are overweight and below that you are underweight. Adults with anorexia have a BMI below 17.5. If you are under 18 years of age, normal weight is assessed by using special age-related BMI charts.
(Reminder: A BMI below 18.5 is considered underweight, 18.5 to 25 is considered "normal," 25 to 30 is considered "overweight," and 30+ is considered "obese," according to the Centers for Disease Control and Prevention.)