Newsflash: There is no such thing as a "universally healthy" diet.

If you’re contemplating a diet that claims it “works for everyone”, step away. It’s a lie.

A new study of mice has found that weight gain or loss all depends on how an individual’s genes react to certain diets.

Basically, it doesn’t matter whether your friend had great success with the Atkin’s diet, your neighbour swears by giving up sugar or you read about a woman who changed her life through an obscure diet, it doesn’t necessarily guarantee success for you.

Delivering the results at the Allied Genetics Conference, North Carolina State University’s William Barrington said the team found four strains of mice fared very differently on four different diets.

The mice reacted differently to the different diets. Image: iStock

The four diets tested were a fat-and-carbohydrate-laden Western diet, traditional Mediterranean diet, Japanese diet and a low-carbohydrate, fat-rich diet aka the ketogenic diet.

The A/J strain mouse were almost unaffected by all dietary changes, with little weight gain or changes to insulin and cholesterol levels across any of the four diets.

NOD/SHiLtJ mice experienced a rise in blood sugar (a sign of diabetes) on the Mediterranean diet, but decreased on the Japanese diet while the FVB/NJ mice didn't gain any weight on the Western diet yet became obese with high cholesterol and a host of other health problems on the ketogenic diet.  Watch: How much sugar is really in your favourite drink. Post continues after video.


The C57BL/6J experienced the opposite, developing health problems linked to heart disease and diabetes on the Western diet as well as gaining weight on the Mediterranean diet.

The ultimate takeaway (excuse the pun)? "There's no universally healthy diet," Barrington concluded.

Accredited Practising Dietitian Melanie McGrice agrees that a 'one-size-fits-all' diet doesn't exist.

"We are all different – we have different genes, different lifestyles, different likes and dislikes, so our diets need to be different," she told Mamamia(Post continues after gallery.)

"Many diet plans are based on what has worked for one person, but that doesn’t mean that it will work for you."

There are number of different factors that determine how successful a diet plan will be.

"Your genetics, hunger levels, eating cues, medical conditions, medications, body composition, nutritional status, food preferences, physical activity levels, lifestyle and goals [all contribute]," she says.

"This is why it’s so beneficial to have a comprehensive Nutrition Assessment with an Accredited Practising Dietitian – we determine your unique needs as opposed to putting everyone on the same plan."

Food and execise

Image: iStock

The study's findings support a human study published in Cell journal last year that found individuals' blood sugar levels rose differently after eating the same food.

The team are currently trying to identify the genes in each strain that control the different responses to food.

Unfortunately, there's still no way to predict how a human body will react to a specific diet - but you can bet it's varied.

Image: iStock.
h/t: Science News