Original Poster, forgive me I'm not a health professional or an academic, so I'm sure my answer won't be broad enough. I know of course that this doesn't apply to every obese person. But i'll give it a go
What would you say are the causes?
Depression, low self esteem, perfectionism, childhood abuse. The human condition to a certain extent. We all have the ability to feel negative emotions. We all cope with these in different ways. Some people's coping mechanisms are healthier than others.
Over eating, under eating, bingeing, purging are ways of using food to effect your emotions.
Why is the incidence rising?
Because food is cheap, readily available and socially acceptable? (ie, far easier to buy biscuits rather than vodka or herion) Out of all substances that it possible to abuse in order to block out negative emotions, food is the easiest to get hold of and the most difficult to give up completely. Because you can't ever just give it up. You need to eat
Risk factors?
I don't know........ upbringing? example set by parents? personality type? Phsiological make up? (ie propensity to burn fat or store it?)
Symptoms?
An unability to maintain a healthy weight and relationship with food? Obesity? Depression?
Signs?
Not sure what you mean by this one?
Treatments?
CBT? Counselling? Community Support?
Prognosis?
Varies with the individual
What should health care professionals be doing about it? It's hard not to end up in the territory of dietary advice, exercise and management or avoidance of obesity related conditions.
I think a broader understanding of the relationship between mental health and obesity would help. This leaflet is a good example. I would think the majority of overweight people will either be depressed, distressed or angry with it. All negative emotions that then will be dealt with by comfort eating maybe. Not in all. Yes maybe some will be galvanised into action. But I'd doubt the majority.
Although I don't think the subject of the risks being overweight in pregnancy should not be raised for fear of upsetting an overweight person, I think that it should be approached with more understanding and support than the MW's I've encountered have had.