SWITCHING to skimmed milk could slow down ageing and help you live longer, scientists claim.
New research found that for every one per cent increase in the fat content of milk someone drank, their DNA aged the equivalent of more than four years.
1
It suggests that those who drink red-topped milk, which is around 0.3 per cent fat, may look more youthful than those who drink blue-top milk, which is 3.6 per cent.
The study, published in the journal Oxidative Medicine and Cellular Longevity, analysed the genes of almost 6,000 US adults.
They were also asked about their diets and what type of milk they drank.
If you’re going to drink high-fat milk, you should be aware that doing so is predictive of or related to some significant consequences
Professor Larry Tucker
Study leader Professor Larry Tucker said: “It was surprising how strong the difference was.
“If you’re going to drink high-fat milk, you should be aware that doing so is predictive of or related to some significant consequences.”
Cell stress
The scientists, from Brigham Young University in Utah, worked out the age of DNA by looking at the length of certain parts of chromosomes, which get shorter with age.
They believe that the saturated fat in milk puts stress on cells, which can cause damage and contribute to death of tissues in the body.
However, they were unable to prove their findings – because they only looked at the effects and not the causes.
The researchers used data from the National Health and Nutrition Examination Survey as well as carrying out questionnaires on 5,834 people.
They then analysed the link between the length of the end of chromosomes – the coiled structure in which DNA is present – milk intake frequency and its fat content.
Each time a cell replicates, we lose a tiny bit of those ends which is why older people have shorter telomeres, they said.
Biological age
Researchers said for every one per cent increase in milk fat consumed, telomeres were 69 base pairs shorter in the adults studied.
This works out as the equivalent of four additional years of biological ageing, they said.
They also found that adults who consumed whole milk had telomeres that were a 145 molecules shorter than non-fat milk drinkers.
That’s the equivalent of nine years, they said.
Just under a third of participants reported drinking full-fat whole milk and 30 per cent reported drinking two per cent milk.
Meanwhile, one in 10 consumed one per cent milk and 17 per cent drank non-fat milk, while 13 per cent didn’t drink cows’ milk at all.
Milk is made up of about two thirds of saturated fat, which is thought to trigger inflammation in the body and increase oxidative stress on cells.
The authors wrote: “It appears that the milk fat and cellular ageing association identified in this investigation was probably due, in part, to increased inflammation and oxidative stress caused by increased consumption of saturated fat.”
Controversial food
Professor Tucker added: “Milk is probably the most controversial food in our country.
“If someone asked me to put together a presentation on the value of drinking milk, I could put together a one hour presentation that would knock your socks off.
“You’d think, ‘Whoa, everybody should be drinking more milk’.
“If someone said do the opposite, I could also do that. At the very least, the findings of this study are definitely worth pondering.
“Maybe there’s something here that requires a little more attention.”
Professor Tucker said the findings support current dietary guidelines which encourage adults to consume low-fat milk and not high-fat milk, as part of a healthy diet.
He added: “It’s not a bad thing to drink milk. You should just be more aware of what type of milk you are drinking.”
