Dietary Senolytics Combat Aging Inflammation By Clearing Zombie Cells

Key Quotes

"So we cover 11 aging pathways, kind of our 11 best opportunities for slowing the sands of time. And the each with kind of practical takeaways. It does, this is the part one of the book. It is kind of the nerdy section. It goes really deep into kind of the interesting biology and mechanisms. But, you know, really do kind of like, okay, but here's the bottom line. You can skip all this. Just, you know, this is the foods to eat, this is the activity to do, blah blah blah."

Dr. Greger explains that his book delves into the biological mechanisms of aging, but he emphasizes that readers can focus on the practical advice regarding diet and lifestyle without needing to understand the complex science. This highlights his approach of making scientific information accessible and actionable for a general audience.

"So our cells in our body only, uh, divide about 100 times before they stall out. This is the so the so-called Hayflick limit. We used to think cells just kind of, you know, divided forever. But they only divide 50 times. And this is good because that's a protection against cancer. We want cells to naturally kind of put themselves out to pasture, being replaced by new cells from the stem cells."

Dr. Greger introduces the concept of the Hayflick limit, which is the finite number of times a normal human cell population will divide before cell division stops. He frames this biological limit as a beneficial mechanism that protects against cancer by ensuring cells are eventually replaced.

"Unfortunately, our immune systems start to decline with age. And so what happens is our immune system's ability to clear out these cells declines, such that our body's tissues get littered with these senescent cells, spewing out inflammation. And one of the reasons why levels of inflammation climb with age."

Dr. Greger points out that as people age, their immune system becomes less effective at removing senescent cells, also known as "zombie cells." He explains that this decline leads to an accumulation of these cells, which then release inflammatory compounds, contributing to the rise in inflammation observed with aging.

"And so, two pronged approach. First, we prevent cells from going prematurely senescent. So they should make it to 50, but they suffer damage to their DNA from free radicals, from oxidative damage to their DNA as a protective mechanism because it could cause mutations or something, they kind of go out to pasture early. Um, and so we can decrease oxidative stress by flooding our body with antioxidant rich foods like the berries and greens and really healthy foods."

Dr. Greger outlines a two-part strategy for managing cellular senescence, starting with prevention. He suggests that by consuming antioxidant-rich foods such as berries and greens, individuals can reduce oxidative stress and DNA damage, thereby preventing cells from becoming senescent prematurely.

"And the second is we look for senolytic compounds, ways to clear these zombie cells from our bodies. There's been a number of drugs that have been put to the test. Unfortunately, these drugs have kind of some severe side effects. Um, and so there are certain, uh, certain medical conditions in which senescent cells play a key role and in which case the benefit risk analysis might actually support use of some of these toxic drugs. But for kind of the general public, um, we're really left with senolytic compounds in natural foods."

Dr. Greger discusses the second approach to managing senescent cells: using senolytic compounds to clear them. He notes that while drugs exist, they often have severe side effects, making natural food-based senolytics a more suitable option for the general population, except in specific medical conditions.

"One is fisetin, which is really only found one place in concentrated form. That's the strawberries. So that's why I end up in the book and that chapter recommending fresh frozen or freeze-dried strawberries into your daily diet."

Dr. Greger identifies fisetin as a key senolytic compound, which he states is primarily found in strawberries. He therefore recommends incorporating fresh, frozen, or freeze-dried strawberries into one's daily diet as a way to consume this beneficial compound.