Unfortunately, some take control too far - as demonstrated by Desperately Hungry Housewives (10.35pm, BBC1, 28 April).
Unlike the obese teenager who packed herself off to a US fat farm to shed the fat and confront the reasons for it (Georgia's story: 33 stone at 15, 10.35pm, BBC1, 21 April), these joyless, self-obsessed women commanded little sympathy.
Former anorexic Jane had a fantastic house, a loving husband, kids and plenty of friends. Yet the now bulimic 50-something liked nothing better than to categorise her food as white (good) or black (bad), regularly threw up when hubby had gone to bed and looked as though her dog had just died when informed by her doctor she'd put on a couple of pounds.
Ultra-gamine Zoe was equally obsessive. The recovering anorexic, whose illness "took hold" when she was pregnant, was constantly checking her BMI chart, trying to think positive thoughts about food and fretting over going out for a meal. Meanwhile, bewildered mum Georgia, whose weight plummeted to four stone at one point, was on a diet to shift the baby fat - and sliding back into bad habits.
Much was made of the psychological triggers for the women's conditions - bulimic Tracey, the most sympathetic of the four and the only one who had a job, was trying to cope with being a single mum, the aftermath of divorce, "a few miscarriages" and child abuse.
The narrator went to great lengths not to judge, but I found it hard not to. Wag-fixated young girls have some excuse. This lot with their wistful smiles and furtive ways, I'm not so sure. Not only were their eating disorders self-inflicted, they'd wallowed in them, indeed defined themselves by them, for years. Instead of controlling food, they'd allowed it to control them.
Ironically, it was Tracey, the only one who seemed ashamed of her disorder, who summed up the viewer's moral dilemma perfectly: "I'm a grown woman. I have two children. I have a job. I'm studying. I'm a sensible person. So why do I do this?"