Dietician Dave Shaw said the nutrition advice was misguided and did not teach clients anything about healthier food choices.
"It's a very restrictive diet, so you're avoiding a lot of food groups and essentially replacing them with a cup of tea," he said.
"It doesn't really teach you anything in regards to healthy eating behaviours or what foods to include, it only teaches you to stay away from foods."
Targeting young girls was also a concern, he said.
"If you're a young female, which this seems targeted at essentially, it's going to compromise your eating behaviour, and promote eating disorders.
"Those images are really powerful, if someone sees that and sees the end product which isn't often a realistic outcome they are likely to try and do it, and in the end they are not going to benefit from it because they are not learning anything."
Those concerns were echoed by the Eating Disorder Association of New Zealand.
"We have heard of a few young women in New Zealand ordering similar products online and becoming very ill," a spokeswoman said.
"Our main concern is that young dieters with an unknown predisposition for anorexia or bulimia will be drawn to this product."
The products could be abused because they contained senna, a herb that had a laxative effect when consumed in high doses, she said.
"There are inherent dangers in using any form of laxative product for weight control and we would strongly advise against it."
Auckland dietitian Sarah Hanrahan said she was sceptical about any "detoxifying" effects the tea might have.
"The fact that it has three meals made up of food is a big advantage over lots of other detox diets, but at the end of the day your liver does any detoxing that your body needs.
"The notion of needing to go on any type of diet to detox is flawed."
A week of denial and suffering
I shopped around among several "teatox" diets before settling on Australian company Skinny Tea. It cost $37 to order its tea and have it shipped to New Zealand.
The diet required I drink one cup of "specially blended" Skinny Tea Loose Leaf each morning and one cup of Detox Tea Loose Leaf every second evening while following the Skinny Tea Detox Eating Plan.
The plan ruled out meat, dairy products (except yoghurt), eggs, anything containing wheat, processed foods, sugar, alcohol, soft drinks, salt, coffee and other types of tea - leaving me with only fruit, vegetables, fish, grains and nuts to work with.
Day One: As coffee is banned, by the end of the day I have all the symptoms of caffeine withdrawal. Everything else is fine.
Day Two: Caffeine withdrawal has intensified with headaches, fatigue and clammy skin. Really annoyed I can't have eggs on toast for breakfast.
Day Three: Feeling nauseous and having stomach cramps that make it hard to concentrate. Colleagues are taking great joy in inviting me on their coffee runs and offering me banned snacks. Have noticed no "3.30pm-itis" the last few days, perhaps due to no coffee?
Day Four: Getting used to not having coffee, although hot water with lemon just isn't the same. Weekend away with friends off to a depressing start as my (unroasted, unsalted) scroggin replaces the McDonald's everyone else grabbed for the drive.
Day Five: Grumpily munched homemade muesli while everyone enjoyed a cooked breakfast and sipped water while they had cold beers in the sunshine. Cramps intensifying.
Day Six: Yet to feel "energised and invigorated", instead felt lethargic and drained. Don't feel like eating any food due to stomach cramps.
Day Seven: The bathroom scales told me I had gone from 58kg to 56.5kg. That seemed a lot to lose in a week, but considering I haven't eaten in a day and have lost my will to live and my grip on reality, it might make sense.
5 fad diets to avoid
• Lemon Detox Diet _ Seven to 14 days of consuming only a drink made of lemon juice, cayenne pepper and an expensive syrup.
• Breatharian Diet - Followers stop eating and live off air and sunlight alone.
• Dukan Diet - This protein-heavy, low carb diet can lead to constipation, a lack of energy and bad breath.
• hCG Diet - Eat only 500 calories a day for 40 days while also taking hCG, a hormone produced in placentas and found in pregnant women's urine.
• The Grapefruit Diet - Eat nothing but grapefruit for 12 days, then eat normally for 12 days. Repeat.
* Performance nutritionist, clinical dietitian and health expert, Dave does his best to make sense of what we eat, blogging for Life & Style online.
If you have family or friends who are in need of help for an eating disorder or you are concerned about their relationship with food, contact the Eating Disorder Association of NZ.
National Helpline: 0800 2 EDANZ
Email: info@ed.org.nz
