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The Pulse

Red flags to spot a dodgy diet

by Cathy Johnson

Whether it's shunning all grains and dairy on a paleo diet, or bingeing on fruit juice to cure your cancer, "fad diets" push some misleading ideas about healthy eating. But knowing some red flags that are common signs of dodgy diets can help you avoid getting sucked in.

fad-diets_300x150iStockPhoto | bhofack2

Confused by messages you should "quit sugar", stop eating grains, dairy, and legumes, start "clean eating" or detox by drinking lemon water?

These days, fad diets promoted by celebrity nutritionists are everywhere. Most of these experts, including Australian chef and Channel 7 star Pete Evans (champion of the Paleo diet) and journalist and anti-sugar campaigner Sarah Wilson, have no formal nutrition qualifications and much of what they promote has no solid scientific basis. Yet this doesn't detract from their popularity, in fact some might argue their 'anti-medical establishment' stance is part of their appeal. But a recent series of unrelated and high profile 'events' have highlighted the shortcomings of the celebrity diet guru.

"Nutrition is one of the few fields where anyone can be considered an expert simply because they've got a story to tell," says Tim Crowe, associate professor of nutrition at Deakin University, who's been working in the field for decades.

Tell-tale signs of a dodgy diet

Here are Crowe's top three "red flags" that should ring alarm bells when you are scrutinising any new diet regime you hear about:

1. It contradicts generally accepted nutrition and health guidelines.

"Ask yourself, is the same message being repeated by peak health bodies and credible experts? It's the consistency of the message that's important. If organisations like the National Health and Medical Research Council (NH&MRC), the Cancer Council, the Heart Foundation, Diabetes Australia, and so on are all saying the same thing and you're hearing something very different, you're right to question it.

"There is no government conspiracy to make us sick. They want to make us better."

2. It cuts out or heavily restricts whole (or multiple) food groups and/or focuses on one or a few particular foods as having some disease- curing properties.

"You have this fixation with particular types of foods or ways of eating. Buttered coffee comes to mind. Loading up on butter, coconut oil, particular foods that are meant to have some additional health benefits," Crowe says.

In other cases, you're told to exclude whole food groups like grains, legumes and dairy in the Paleo diet

"If you have to exclude foods for a medical reason, that's very different to excluding them because you've jumped on the latest fad because a celebrity nutritionist has told you so," Crowe says.

"If you speak to a dietitian about foods you need to cut out [because of a health condition] they'll give you advice about what other foods you need to make up for the difference [in nutrients you are missing out on]." Generally no such advice is included in fad diets.

3. It is marketed with testimonials instead of scientific evidence

Compelling personal stories about individuals who changed their diet and lost masses of weight or recovered from a horrible illness have a strong impression on people, Crowe observes.

What we're likely seeing is people who would have lost weight because they reduced their kilojoule intake or people who would have got better anyway thanks to either normal remission of their cancer or because of treatment they're having, he says.

"You tend to only hear about people who claimed to have beaten a cancer by following a diet. You don't hear so much about people who made the same changes and died from their cancer. As far as the public are concerned, the anecdote is much more powerful than a clinical trial [a scientifically designed research study]."

For more tips on avoiding dodgy diets see, see here and also Crowe's light-hearted blog post 10 ways to spot a fad diet

The appeal of a 'quick fix'

While self-appointed nutrition experts are nothing new, social media has given them a "very loud influential voice", Crowe says.

They once focused typically on promoting alternatives to evidence-based weight loss methods, but now make broader claims that suggest they "know how to treat all our major chronic diseases the rest of us true experts have no idea about".

"They put a new spin on it, introduce some kind of conspiracy theory, some form of magical ability to cure disease… all with a very quick fix."

University of NSW nutrition lecturer Dr Rebecca Charlotte Reynolds agrees: "So many of us are stressed and tired and looking for quick fixes," she wrote in a recent article on the power of celebrity nutrition. "We're sold a whole lifestyle and the idea that food can be a magical elixir that can cure all ails."

Both Crowe and Reynolds point out that fad diets can have a positive influence because they often advocate eating lots of wholesome unprocessed food and lots of fruit and vegetables.

"The diet might make them feel better but that's just because they're eating better," Reynolds says. "If they followed the Australian dietary guidelines they'd feel exactly the same."

But advice that is not so healthy is usually added to the mix and often this involves cutting out food groups that provide important nutrients or eating a lot of a food that may pose a health risk. (For example, critics of some low-carb diets point out they often suggest red meat intakes above those recommended for minimising bowel cancer risk.)

What is "clean eating"?

Before her cancer diagnosis was questioned, social media personality, app creator and author Belle Gibson promoted eating "clean" with measures including cutting gluten, dairy and genetically-modified foods from her diet.

But there is no universally accepted definition of what clean eating is, says Crowe. "It can be whatever moral judgement a person applies to a food." It usually involves eating less processed food but it also includes some level of moral superiority for how a person is eating, he says.

On social media in particular, there is "a lot of 'I'm on the moral high ground [because] I'm eating cleaner than you."

Diets as cancer cure

As for dietary regimes that claim to cure cancer, many like the Gerson therapy used by Jess Ainscough, have been around for decades and are discredited by organisations like Cancer Council Australia.

Adopting healthier eating patterns is a good move, whether you have cancer or not. And there's some evidence healthy eating can reduce the risk of certain cancers and/or their recurrence.

"But taking a dietary regime to an extreme can actually compromise treatment if it means a person is foregoing conventional treatment or if it also means they're undergoing some dangerous practices like coffee enemas, which can be quite harmful."

(Coffee enemas can result in perforation of the bowel and can cause dangerous changes in electrolytes – minerals in body fluids that influence important processes. There is no evidence they help control cancers.)

Questions to ask yourself before adopting a fad diet

These are Rebecca Charlotte Reynolds' suggestions:

1. Do I have particular health concerns that mean I need to research my options more widely because the wrong advice might be especially risky?

"Be really careful about taking non-evidence based advice if you've got a medical condition," she warns.

2. Am I looking to this diet as a way to fill a hole in my life I haven't been able to fill in other ways? Am I actually depressed or anxious? Have I got an eating disorder? Would I be better served by advice from a health professional like a psychologist?

"People who become obsessive about a certain way of living might be making themselves feel better about something else. Nutrition is very emotional."

3. How much am I falling in love with the image being presented rather than what is actually being promoted? What am I really buying into here? Celebrity nutritionists generally look good, Reynolds says. "We're all obsessed with appearance because it means so much in modern society. You think if you follow someone rich or beautiful you might become that yourself or it might take away your stresses."

Published 24/03/2015