"I just had no idea that fruit had so much sugar. I was a big fruit eater. Yes, I'd have the odd cake or dessert, but I wouldn't be spending all day pigging out on it."
Tiffen, who with husband Robbie, runs a gunsmiths outside Christchurch, slowly reduced her estimated daily consumption of 30 teaspoons of sugar to just six. She increased vegetables, protein and meat, while cutting carbohydrates. Over nine months, she lost a staggering 20kg "with absolute ease".
Amazed with the results, friends and family followed suit, with similar success. In a frantic fortnight, she wrote a book, A life less sugar: How I lost 20kg by reducing my sugar.
She self published, running off copies on printers from home. It was soon picked up by nationwide books retailer Paper Plus and has now sold 4000 copies.
Today, along with close friend Leigh Brown, she is launching a cookbook that features 35 low-sugar recipes. It has already pre-sold 1300 copies.
Tiffen stresses that she's not a qualified dietician or nutritionist. "Education is the key to people winning this battle."
Her husband and two sons, aged 10 and 12, are also seeing the benefits, snacking less, feeling more healthy.
She is now around 60.5kg.
If others want to follow her example, she urged them to reduce their sugar intake gradually.
Sugar limit
• Men: 9 teaspoons - the equivalent of two large bananas or two medium apples.
• Women: 6 teaspoons - the equivalent of 1.5 large oranges or a large apple.
• Children: 4 teaspoons - the equivalent of one large banana or nearly one medium apple
• The books are available from Paper Plus nationwide, Piccadilly Bookshop Avonhead, Body Audit NZ, Paper Power Thames, Richmond Freshchoice in Nelson, and McLeods Booksellers.