Milk Fat Causes More Aging?
Can drinking whole milk make you age faster? That’s the crazy conclusion of a recent study, but regrettably, nobody seems to have noticed that the study results make no sense or at least tell a different story than the one the news media has been slinging. So let’s dive in.
The New Study
A recent study from Brigham Young University purportedly found a correlation between drinking milk with various fat-levels and cellular signs of aging. In this study of 5, 834 American adults the authors found a link between drinking whole milk and shorter telomere lengths. The people who drank milk with a lower fat content had longer telomeres.
What’s a Telomere?
Telemores are nucleotide sequences capping our DNA strands, not unlike the plastic at the ends of shoelaces that prevent fraying. The word is derived from the Greek (telos, which means long and meros, meaning part). As the cell divides, it chops off a little bit of the telomere and as a result, as we age, our telomeres get shorter. Hence, in these types of studies, shorter telomeres are associated with aged cells.
Milk and Telomeres
This study correlated telomere-length with the consumption of milk of varying fat-levels; for every 1% increase in fat, telomeres were roughly 69 base pairs shorter. The widest gap—from whole milk intake to skim milk intake—showed even shorter telomeres. Yet, a particular finding of the study seems to raise more questions than it answers; those who did not drink milk at all showed shorter telomere lengths than those who drank 1% or nonfat milk.
That’s a serious problem for this study. Meaning, if milk fat was causing telomeres to shorten, those who drank no milk should have telomere lengths the same as those who drank non-fat milk. Hence, the media’s hysterical headlines like these:
Drinking 1% rather than 2% milk accounts for 4.5 years of less aging in adults!
High-fat milk drinkers may age faster than low-fat milk lovers, study finds
Drinking 1% Rather than 2% Milk Accounts for 4.5 Years of Less Aging in Adults
Aren’t supported by the study results! In fact, it’s not clear how the study even got published with conclusions like this one:
“In the current study, those reporting regular high-fat milk intake (full-fat or 2%) had substantially shorter telomeres, on average, than those consuming low-fat milk (1% or nonfat), indicating that high-fat milk intake goes hand-in-hand with increased cellular aging. “
Turns out that the authors recognized that the whole study may have been an association is causation fallacy.
A long time ago a study was done that showed that coffee drinkers had higher rates of cancer and the alarm bells in the media sounded. However, it turns out that coffee drinkers also smoke more, which accounted for the association. So we all need to be very careful about drawing any conclusions in a study that finds A is associated with B. Especially when the data doesn’t add up as is the case in this study.
Here’s what the study authors said: “However, individual foods are seldom eaten in isolation…Adults who preferred nonfat milk consumed less dietary fat and less saturated fat, as well as more dietary fiber, than their counterparts…However, it is possible that other dietary differences account for some of the biological aging differences among the milk fat categories.”
Meaning all the study may have done is to identify various subtypes of people who do other things to protect their health.
Fat is a Great Concentrator of Toxic Chemicals
Many of the toxic chemicals in our environment are soluble in fat. That means that they tend to concentrate in the fat we find in the foods we eat. Hence, the study could be showing that milk fat exposure is merely a proxy for toxic chemical exposure. However, then there’s the telomere length of the people who drank no milk.
The upshot. NEVER trust the headlines on any science story! The media’s job is to sell clicks and eyeballs. This study is a mess and certainly doesn’t prove that milk fat has anything to do with aging faster. Hence, if you like whole milk, find a good organic producer who is less likely to have cows exposed to chemicals and drink up!
(1) Tucker LA. Milk Fat Intake and Telomere Length in U.S. Women and Men: The Role of the Milk Fat Fraction. Oxid Med Cell Longev. 2019;2019:1574021. Published 2019 Oct 28. doi: 10.1155/2019/1574021