R.I.S.H: Radical. Idea. or Spurious. Hypothesis?
The eating-disorder field has a long history of introducing new labels. The latest — RISH — may be the most questionable yet
Research. Is. Somewhat. Hypothetical.
Imagine that a new label was created for some people presenting with eating difficulties — a label introduced without robust research, empirical evidence or consensus across the eating-disorders field. Now imagine that this label quickly began influencing treatment decisions or even determining whether some patients received care at all.
Unfortunately, we don’t need to imagine this. Because there is a new kid on the ED block, and this little upstart is being embraced wholeheartedly by some in the field.
In recent years some clinicians at Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust believed they had identified something new — an unusual, atypical presentation of restrictive eating that might not be an eating disorder. The concept was presented as a distinct type of restrictive eating behaviour. Soon guidance on identifying and treating this supposed presentation began circulating online.
And just like that, a new acronym entered the eating-disorder lexicon: RISH (Restrictive Intake Self-Harm).
In medicine, new clinical concepts normally emerge through observation, hypothesis and then rigorous testing. With RISH, that sequence appears to have been reversed.
ED field has form when it comes to introducing new categories that lack solid evidence yet end up shaping treatment pathways. Labels such as SEED (Severe and Enduring Eating Disorder) may affect the way patients are treated including shifting the focus towards ‘quality of life’ rather than recovery, despite a lack of evidence for this approach. Atypical Anorexia (AA) has caused immense harm by suggesting that someone has a different type of illness from AN because they happen to be a ‘healthy’ weight at the time when they’re seen by a doctor. Ooh, and let’s not forget the insidious idea of TA (Terminal Anorexia), which has quietly crept through the darkness and into clinical thinking despite no evidence that AN is ever inherently incurable.
Against this backdrop, RISH may simply be the latest example of a troubling trend: renaming problems instead of understanding them.
RISH. Is this. Separate. from AN?
The central question is, of course: is RISH really a different condition to anorexia nervosa — or simply anorexia described differently?
Fans of RISH suggest that restricting eating in these patients functions primarily as a form of self-harm or ‘emotional regulation’. Restriction is framed as a way of coping with distress or communicating emotional pain.
But the behaviours described under RISH are strikingly similar to those seen in AN:
Often complete refusal inc. fluids. — well documented in anorexia.
May eat normally/eat high calorie foods sporadically. People with AN don’t have a single way of eating or a single type of food they will eat, and many still enjoy food. Sometimes they might eat a bar of chocolate. Or some ice cream. Or a piece of cake. That doesn’t mean they don’t have AN.
Rapid onset of severe restriction — many parents of people with AN report their children becoming unrecognisable almost overnight.
Restriction concerns and compensatory behaviours are freely described/displayed — in my experience, this occurs in AN, particularly early in the illness when the individual is confused by the messages their brain is giving them.
Self-harm highly likely. Just as it is in AN.
Presents with a mood ‘roller coaster’. Anyone who is starving is likely to be on a mood roller coaster — they’re in a fight for survival, after all. And this is certainly true about most people with AN.
Low self-esteem and a poor sense of identity are core constructs within RISH. Show me a patient with AN who has high self-esteem and an identity that isn’t entirely consumed by the illness, and we can talk.
Excessive exercise may be observed in those with RISH… teams should avoid the assumption that exercise is driven exclusively by a desire to burn calories and lose weight. We do not yet know what drives hyperactivity in AN, and it may be different in different people. Some suggestions are: OCD-type thinking around numbers; an evolutionary migration response; or the body’s attempt to keep warm. A percentage of all mammals display a similar behaviour when food is restricted (Activity Based Anorexia) — and as humans are mammals, why would we expect them to behave differently? Imposing a simple psychological explanation on to this behaviour ignores this evidence and displays a worrying lack of understanding.
The authors themselves acknowledge the remarkable overlap between RISH and AN. But if the overlap is so substantial that clinicians struggle to tell the difference, the obvious question arises: what exactly distinguishes the two? At present, the answer appears to rely largely on interpretation of motivation rather than measurable differences in biology, course or treatment response.
New categories can have real, negative consequences for patients. They shape how clinicians interpret behaviour and how services respond. If someone is labelled as a RISH patient rather than an AN patient, they may be turned away from services that believe they don’t have the expertise to treat RISH. And a label that frames restriction primarily as psychological self-harm risks shifting attention away from the biological effects of starvation.
Real. Issue: Starved. Humans.
The greatest weakness in the RISH concept is its failure to account for one of the most well-established facts in ED research and beyond: malnutrition profoundly affects the brain.
In the 1940s, the Minnesota Starvation Experiment — documented in The Biology of Human Starvation — demonstrated that hunger alone can cause:
Obsessive thoughts about food
Severe mood instability
Irritability and anxiety
Social withdrawal
In other words, many behaviours interpreted as psychological dysfunction are direct consequences of malnutrition.
When a brain is severely undernourished, decision-making, emotional control and insight are all compromised. In that state, asking patients to explain the ‘function’ of their restriction risks misunderstanding what is happening biologically.
Malnourishment is not a symptom of anorexia; it is a driver of the illness. This is why renourishment should always be central to recovery from AN. Weight restoration improves cognitive function, stabilises mood and allows meaningful psychological work (if needed) to take place.
Removing food and weight from the centre of treatment — as the RISH proponents suggest — ignores this reality. The danger of RISH is that it appears to lean heavily towards psychological interpretation while downplaying the powerful biological effects of malnutrition. Clinicians are taking the illness at face value and asking why someone is doing this to themselves instead of the question they should be asking: why is this person’s brain doing this to them? It’s an enormous step backwards in eating disorders.
Really. Is. Science. Happening?
Ultimately, the emergence of RISH highlights a broader issue within ED services: the ease with which new diagnostic ideas can spread despite limited evidence.
Acronyms multiply. Categories shift. Treatment pathways change. But the fundamental importance of renourishment in treatment does not. Before introducing a new label, the field should ask a simple question: does this improve patient care — or does it risk obscuring the illness we are only just beginning to understand.