This just may be Elle Macpherson’s secret to looking half her age.

In a revealing interview, in which the 51-year-old model details a number of her health tips and tricks, Macpherson says she swears by pH testers.

When asked by The London Evening Standard what’s the most shocking item in her purse, she shared: “A pH balance urine tester kit to check that I’m in an alkaline state,” said the mother of two. “I believe that most ailments come from having an acidic body.”

Adding veggies and water and limiting salt can affect levels.

Another insider secret to keeping her 6-foot frame in impeccable shape is draining her lymph nodes, which reportedly can flush toxins from the body and provide other benefits.

In fact, it’s the first thing she does whenever returning to London. “[I] visit my nutritionist Dr. Simone Laubscher on Harley Street and Shirley and Dr. Sebagh’s clinic for lymphatic drainage,” shared the Australian-born model, who also says vacations are key for her well-being.

As for her diet, Macpherson — who is known as “The Body” — eats three square meals a day and steers clear of red meat, wheat and dairy.

However, she occasionally indulges in three guilty pleasures: “Green & Black’s dark chocolate, digestive biscuits and Marmite.”

This article originally appeared in the New York Post.

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