Does the milk-fat percentage of the milk you’re consuming directly impact how well you’re biologically aging? A recent study says that there’s more to the skim vs. whole milk controversy, and it’s specifically indicative of changes to your chromosomes.
Markers of biological aging include the length of telomeres, the ends of chromosomes. Telomeres are the best way to measure the body’s aging process because they change and shorten in real-time. Telomeres shorten each time cells divide and duplicate, whether in normal cell division or during disease processes or oxidative stress. Telomeres do not regrow. As the cells in the body go through natural aging processes, or are accelerated by genetic and environmental factors, the telomeres shorten. Examining the length of a person’s telomeres is predicative of how well the person is aging (often called their “biological clock”), and shorter telomeres influence disease risk and mortality.
Led by professor Larry Tucker of Brigham Young University, the research team found surprising consequences of drinking high/whole fat milk versus drinking 1% milk. Adults who drank high-fat milk (including 2% milk, not just whole milk) showed shorter telomeres than those people who drank 1% milk. The percentages in milk fat are more important than just taste preference, and the difference between 1% and 2% is actually quite significant.
Each increase in milk fat of just 1% shortens 69 base pairs of telomeres at the end of the chromosomes, representing 4 years more biological aging. Adults who drank whole milk showed shortening of 145 base pairs! The adults in the study either drank milk daily or weekly.
The significance of milk fat on adult telomeres didn’t stop there—Tucker discovered that adults who did not drink any cow milk at all had shorter telomeres than those who drank 1% milk.
Milk may provide a protective quality for telomeres when consumed at low fat percentages, preferably 1%; beyond that, milk appears to alter our chromosomes markedly. Whole milk should be consumed consciously. Fortunately, switching to low-fat or non-fat milk is an easy fix at the grocery store.
Tucker, Larry A. “Milk Fat Intake and Telomere Length in U.S. Women and Men: The Role of the Milk Fat Fraction.” Oxidative Medicine and Cellular Longevity, vol. 2019, 28 Oct. 2019, doi:https://doi.org/10.1155/2019/1574021.