Additionally, there is evidence eating too much protein long-term can lead to an increased risk of osteoporosis and worsen existing kidney problems.
A study found fruit flies – which share more than two thirds of humans genes – live twice as long when given minimal protein when young.
A typical western diet is high in protein and fats from meat, diary, and eggs – with red meat in particular linked to heart disease and cancer. The researchers also believe their findings could be explained because a low-protein diet produces less toxic lipids secreted by the skin.
Health skin lipids form a natural barrier keeping out dirt, impurities and harmful chemicals that can accelerate ageing.
Having a low-protein diet early in life may help you live longer, scientists found (stock photo)
No recommendations for pregnant women
Scientists from the Francis Crick Institute in London used the fly drosophila melanogaster to understand how diet in early life acts to alter lifespan.
These insects are used in lifespan experiments because it lives for only two to three months, rather than many years. The team stressed that there was bit enough evidence to recommend pregnant women go on low-protein diets to boost their unborn child’s health.
Senior author Dr Alex Gould said: ‘There is evidence in humans and other mammals that a mother’s diet can alter the risk of her offspring developing cardiovascular disease and diabetes much later in life, but the genetic processes underlying this effect remain to be identified.
‘Obviously fruit flies are not humans, and it’s important to be clear that our results in flies are certainly not a recommendation that expecting mothers should eat a low-protein diet.’
HOW MUCH PROTEIN IS RECOMMENDED?
Most people in the UK get more than enough protein in their diet.
The recommended nutrient intake (RNI – which has replaced the RDAs, or recommended daily amounts), advises the following daily intakes.
- 1-3 year olds need 14.5 grams
- 4-6 year olds need 19.7g
- 7-10 year olds need 28.3g
- 11-14 year old males need 42.1g
- 11-14 year old females need 41.2g
- 15-18 year old males need 55.2g
- 15-18 year old females need 45g
- 19-50 year old males need 55.5g
- 19-50 year old females need 45g
- 51 and over males need 53.3g
- 51 and over females need 46.5g
The Department of Health advises adults to avoid consuming more than twice the recommended daily intake of protein.
Toxic flies harmed their neighbours
The study, published in the journal Nature Communications, found adult fruit flies released toxic lipids from their ‘skin’ that shorten their lifespan.
These lipids were less toxic if the fly ate a low-protein diet during its early life, before it became an adult. And surprisingly, the toxic lipids produced by flies not only affect their own lifespan, but also that of other nearby flies.
Doubling the number of flies in a container significantly shortened their lifespan. This showed that the negative effect of population density on lifespan is caused by skin toxins.
Dr Gould said: ‘Like fruit flies, humans also produce skin lipids that moisturise and protect the skin against everyday wear and tear from the environment.
‘But they too can be harmful because they react with sunlight and other stressors in the environment to produce harmful chemicals that can accelerate the signs of ageing.
‘We know that many of the genes involved in making skin lipids are conserved from flies to humans.
‘We now want to use fruit fly genetics to help pinpoint the ones that regulate how toxic they are.’