Study shows why high-protein diets are unhealthy

Study shows why high-protein diets are unhealthy
Credit: Georgi Kirichkov

Researchers in South Australia believe they have found the key to why high-protein diets are unhealthy and can lead to shortened lifespans.

The project used worms and to investigate how diet influenced the speed of . The results clearly showed that speeding up protein synthesis would produce more errors and this is related to shorter lifespans.

The findings by scientists at the South Australian Health & Medical Research Institute (SAHMRI) also support research which suggests carbohydrates aren't necessarily the dieting demons they are sometimes made out to be.

Corresponding author and SAHMRI Nutrition and Metabolism Theme Leader Professor Christopher Proud said his team identified how nutrient supply affects longevity.

"Science has known for some time that eating too much, in particular protein, reduces lifespan; and now we know why," he said.

"Our team demonstrated that increased nutrient levels speed up protein synthesis within cells. The faster this process occurs the more errors are made.

"It's similar to everyday activities like driving – the faster you go, the more likely you are to make a mistake.

"The resulting build-up of faulty proteins within cells compromises health and shortens lifespan."

The research, which has been published in Current Biology, also reinforces established links between a low-protein, high-carbohydrate diet and longer, healthier lives – especially when it comes to brain health.

"Carbohydrates get a lot of bad press, especially in relation to dieting, but the key is balance and knowing the difference between 'good' carbs and 'bad' carbs," Professor Proud said.

"Eating high-fibre carbohydrates like those found in fruit, vegetables and unprocessed grains and seeds will produce the healthiest benefits. This is similar to the traditional Mediterranean which has well-established links to longevity."

"We already knew that lower food intake extends lifespan," Professor Proud said.

"But in our study this effect was lost when we removed the link by which nutrition affects the accuracy of protein , therefore revealing how overnutrition can shorten .

"Since this link also operates in humans, our findings show how lower consumption could promote longevity in people."

Explore further

Protein and carbohydrates outweigh calorie counting: major research from Charles Perkins Centre

More information: Jianling Xie et al. Regulation of the Elongation Phase of Protein Synthesis Enhances Translation Accuracy and Modulates Lifespan, Current Biology (2019). DOI: 10.1016/j.cub.2019.01.029
Journal information: Current Biology

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Feb 19, 2019
I suppose a lot has to do with what is considered a 'high protein' diet. A low carbohydrate diet does not necessarily have to be high protein.
We do know that high carbohydrate diets, particularly in conjunction with fats, tends towards obesity and metabolic syndrome.

Feb 19, 2019
Just more junk from the Vegan crowd. At least they mentioned the harm done by milled grain flour. Excess fruits are bad also due to the high amount of sugars they contain.

Feb 19, 2019
Fruit sugar doesn't break down the same way regular sugar breaks down in the body. It is released more slowly over time through breakdown of the fruit fiber. Vs sucking down a handful of pixie sticks where the sugar is absorbed immediately and without mediation.

High carbohydrate diets, particularly with high fat are extremely high in caloric load obviously. I want to see a study where people eat less than 1600 calories a day and that is largely carbohydrates with maybe 1 serving of meat/dairy and 1 serving of fruit or non-grain veggies. This is more realistic to life even less than 100 years ago where most people were pretty healthy and skinny.

Feb 19, 2019
A hundred years ago. 1816. people were starving when their harvests were confiscated for various war efforts. Still required to continue the hard labor of production. Ever vsaw photos of the banners demanding "Peace & Bread"?
The generation before that? Your average city-swelling proletariat had a diet of bread & beer & tea.

& considered himself & his family damn lucky to get that. They were very happy to have escaped their ancestral feudalties. For the opportunities the big cities offered, especially through education, for their children.

The survivors were your grandparents.

The generations before that the wealthy were infamous for their lavish excesses. War shortages & rationing & women toiling in physical labor.n replacing the men sent off to fight?

Completely changed society in the figure of the willowy mad flapper rejecting the prim & proper bicycling Gibson Girl. Who had rejected the earlier stultifying Victorian Upper Crust luxuries.

Feb 19, 2019
I have a real problem with this study, exceedingly high protein is rough on the kidneys, well known to occur with high protein diets where you kill your kidneys with excess protein and amino acid intake. I think this is a front for human diet restriction in the hopes that many people will starve to death to 'save the planet'

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