I picked up a copy of a magazine called Look last week. There was a section inside which examined celebrities who have gained or lost weight. A picture of the actress Mischa Barton was accompanied by the headline 'Gained Eight Pounds!' On the opposite page, the magazine published a photograph of Barton before the alleged weight gain along with a helpful speculative piece about why she is eating more and getting fat.

On the next page, there was a similar discussion about Rachel Stevens, who is currently appearing on the BBC's Strictly Come Dancing. According to Look, she has lost a stone because of her daily dancing practice.

The articles also detailed the subjects' previous weight, current weight and height and possible eating habits. The obsession with thinness appears to have gone beyond curiosity and morphed into something deeper. Is being thin the new symbol of success?

Mischa Barton, it was claimed, is getting fat because her career hasn't been going to plan and she is comfort eating. Conversely, Rachel Stevens is thin because she has managed to stay in a dancing competition which has re-launched her career.

Our hunger for in-depth knowledge about the stars and their weight is matched only by our hunger for food that makes us grow in bulk as we castigate those who do the same, while admiring the svelte minority.

New research from the Coombe Maternity Hospital in Dublin revealed that one in five women who give birth there are obese. The consequences of being seriously overweight were laid out in stark terms by Prof Michael Turner, who said that the effects on the health of mother and child can be debilitating for life. Medical staff have trouble monitoring the unborn child as scanning equipment struggles to deal with the layers of fat disrupting the view of womb. The babies are at greater risk of being stillborn and those that survive are at greater risk of developing obesity and a condition called metabolic syndrome.

Obesity is the most powerful visible symbol of first-world poverty. It is cheaper to eat bulky sugar and salt laden rubbish than it is to consume healthy food. A whole chicken is more expensive than a bag of frozen, reconstituted chicken pieces expanded with water and filled with preservatives before being covered in batter or breadcrumbs. Brown breads are marketed and priced as luxury items while white starchy bread with added salt is ten a penny.

Recently, I heard a mother explain her logic when it comes to feeding her family on a tight budget. Her local supermarket has a deal on cheap biscuits, which meant that three packets of them cost the same as a small bag of apples. Such shopping decisions are mirrored many times over by those who, through limited means, succumb to the large retailers who push cheap foods that provide sugar or salt in large amounts and little else.

The government claims to be making some attempt at tackling the obesity problem, which costs the health service in the region of €339m every year, but the 2005 recommendations which resulted from the setting up an obesity taskforce have yet to be fully implemented.

The long-term costs of treating the chronically overweight are most likely incalculable, what is certain is that those born to obese mothers have almost no chance of escaping this new manifestation of poverty. The proliferation of fast-food outlets and convenience stores in urban areas exacerbates the problem.

As we hurtle towards crisis levels in obesity rates, magazines such as Look which monitor the weight of celebrities continue to sell well. Being lithe and thin is no longer a symbol of beauty but a talisman of wealth and status. The Western world has a new measure of depravation borne out in ever expanding waistlines.