Even for a duchess, Dukan diet tops the list of bad breath causes

There are hundreds of bad breath causes out there, and people looking for the perfect body may incur halitosis as a side effect of their diet, particularly if the regimen is extreme. Kate Middleton, the UK's Duchess of Cambridge and at the moment perhaps the most famous adherent of the Dukan diet, may suffer from bad breath caused by eating so much protein, according to the International Business Times (IBT).

Founded by French neurologist Pierre Dukan, this diet is a protein-heavy eating schedule that promises quick results and dramatic weight loss. It consists of four phases, each of which adopts a bit more fruits and vegetables than the one before.

The first, "attack" phase consists entirely of protein. According to the UK Daily Mail, this stage of the Dukan diet can last between one and 10 days, during which time dieters are encouraged to eat nothing but meat, seafood and eggs.

The IBT adds that, during this period, the diet also includes drinking plenty of water, consuming a small amount of oat bran and walking just 20 minutes per day.

The immediate results may include rapid weight loss. However, numerous health authorities warn that this trimming effect comes at a high cost.

For one thing, an all-protein diet typically results is awful halitosis. This is because the body goes into a state of ketosis. Fed only proteins and fats, the body burns its own fat cells in order to cover the energy gap. What results is an excess of ammonia and ketones in the blood and, as a result, on the breath.

The IBT noted that, of the many bad breath causes, ketosis is one of the more reliable, meaning that Dukan dieters like Kate Middleton may need to invest in specialty breath fresheners.

In this case, sacrificing fresh breath for one's body is just the tip of the iceberg, experts warn. On CBS's The Early Show, registered dietitian Keri Glassman emphasized that this fad is similar to the Atkin's diet, both in its methods and its results.

"This is not something I'm a fan of. I think a lot of Americans are gonna try it, because of all of the success...across the pond," she told anchor Rebecca Jarvis, referring to the diet's popularity in Europe. "However, it is not something to do for lifelong weight loss, and especially for lifelong health."

Health experts told the news source that the diet's signature bad breath and constipation likely cancel out any sexiness the regimen confers.