 Identifying simple strategies to prevent or delay age-related diseases is a major public health concern, but how could you measure the effects of such strategies? Well, telomere length is a reliable hallmark of biological aging and the risk of developing age-related chronic diseases. For those of you who missed all my telomere videos, which date back over a decade, what is a telomere and why does it matter how long they are? Telomere comes from the Greek for end part of our chromosomes. Telomeres cap the ends of our chromosomes, like shoelace tips, to essentially keep our DNA from fraying. Telomere length is important since there's a minimum length required, but every time our cells divide, a bit of the telomere is lost. And once they get too short, the cell can die. That's why telomeres are sometimes called the molecular clock of cells. Every year, they get shorter and shorter, kind of like life's fuse. But in some people, that fuse burns faster than in others. Accelerated telomere shortening has been identified as a key biomarker for accelerated aging, disease risk, and diminished longevity. There's some good news. Telomere shortening can be counteracted by an enzyme in our cells called telomerase. Telomerase can replenish the lost bits and elongate our telomeres. How can we boost this enzyme to, in effect, reverse cellular aging? Exercise may help. Those with high levels of physical activity have longer telomeres, whereas obese individuals and smokers tend to have shorter telomeres, along with those getting inadequate sleep. But what about nutrition? Globally, we might expect that any antioxidant or anti-inflammatory diet could be protective for telomeres. So we're talking like a whole food plant-based diet, with a reduced intake of meat and, in fact, swapping out animal protein in general in favor of plant-based proteins. Given that plant-based foods have well-known antioxidant and anti-inflammatory effects, there are fair grounds to believe that the consumption of plant-based foods can help to counteract telomere attrition. But you don't know if it actually would, until you put it to the test. Dr. Dean Ornish, along with a Nobel laureate who co-discovered the telomerase enzyme, studied the effects of comprehensive lifestyle changes on telomerase activity and telomere length, using the same plant-based diet and lifestyle program shown to reverse the progression of heart disease and early-stage prostate cancer, and maybe even early-stage Alzheimer's, and telomere length shortened in the control group, and they aged five years as expected, but didn't just not shorten as much or hold steady, but actually lengthened in the plant-based lifestyle group. Whereas in a similar study across a similar timeframe, there was no difference in telomere length when just giving people the more typical low-fat dairy, skinless chicken breast, generic type healthier dietary advice. Antioxidant-rich plant foods help maintain telomere length. In contrast, total and saturated fat intake and consumption of refined flour grains, meat products, and soda relate to shorter telomeres. People eating more anti-inflammatory diets tend to have longer telomeres, and the greater the anti-inflammatory potential of the diet over time, the greater potential to significantly slow down the rate of telomere shortening. Those with the most pro-inflammatory diets had almost twice the risk of accelerated telomere shortening. The most pro-inflammatory food component is saturated fat, found in meat, dairy, eggs, and junk, along with other pro-inflammatory food components like cholesterol and trans fat. Make it three, these tend to be anti-inflammatory, but when put to the test, fish oil supplements fail to have any significant telomere effects. The most anti-inflammatory food component is fiber, and indeed, if you look at dietary fiber and taking telomere length in a representative sampling of thousands of U.S. adults, even though nobody was eating enough, the more fiber people consumed, the longer their telomeres tended to be. Since there appeared to be a straight line increase, they could do the math, and appeared that just that 10 gram increase in fiber per thousand calories would equate to four fewer years of biologic aging. Whereas, for example, the consumption of soda appeared to increase cell aging by almost two years per daily serving. Now, of course, diets high in fiber, and diets with significant amounts of fruits, vegetables, and whole grains go hand in hand, so fiber may just be a marker for eating lots of whole healthy plant foods. But are there any specific plants associated with telomere lengthening? We'll find out, next.