Pippa Middleton shares her diet and exercise secrets

It may have been Duchess Kate's wedding in 2011, but all eyes ultimately landed on her younger sister Pippa Middleton. She didn't have to say anything, but the perfect fit of her slinky ivory bridesmaid gown spoke volumes, causing royal watchers everywhere to take notice of the 31-year-old's enviable physique.

Fast forward three and a half years and the world is still captivated by Pippa's beauty and trim figure.

Pippa has a famously lithe physique

Now, the pretty brunette is revealing the diet and exercise secrets behind her athletic frame — and the unhealthy treats she splurges on from time to time. In her new monthly column Mind & Body for the British supermarket magazine Waitrose Weekend, Pippa wrote about the benefits of a diet in moderation.

"I grew up with the belief that good health is about moderation in all things, so I'll be celebrating healthy living through exercise, a balanced diet and a little of the naughty stuff sprinkled in — I'm talking chocolate, crisps [chips] and occasional glass of wine," she wrote.

Not one to try out fad diets, Pippa writes, "I've never done Dukan, attempted Atkins or exercised religiously seven days a week, but I do believe in making healthy choices — keeping refined carbs such as white bread and pasta to a minimum, and sticking to sensible portion sizes."

Earlier this year, Pippa completed a charity bike ride across America

It's no secret that Pippa, who cycled across America for charity earlier this year, is an avid sports fan. She also took some time in her inaugural column to explain how she exercises to stay in shape.

"I know that if I fit in at least three, ideally five, sessions of exercise a week — be it a 30 minute run, an hour's walk or a good game of tennis — it boosts my mood and energy, and helps me sleep and digest better," she said.

She swears by four key exercises, which she goes on to detail in the column — ladders, plié squats, wall pushes and the "classic plank" — which are "quick and great for toning all over."