Weekly Blog

Oct 24

For some, it started with an injury from way back when. For others, it was a more gradual combination of tissues that got a little bit stiffer with age and a change in the strength-to-bodyweight ratio, which allowed things to get a little irritated. For many, it's easy to notice after not moving for a while, like those first few steps out of bed in the morning or standing up from a kneeling position. However, for most, as discussed here, it's probably time for a reframing of the conversation.

Osteoarthritis (OA) is a massive, worldwide problem. Some recent data shows that more than 600 million people across the globe work through it every day. The knee(s) is the most common site, accounting for 56% of the cases. Not surprisingly, a significant amount of effort is directed at finding out how to prevent, reverse, and better manage the problem. The good news is, over the last few decades, a lot has changed, including how we talk about the disease; instead of "degeneration" with the sound of inevitability, there is renewed hope in the many promising ways to manage it. The less good news, as is the case with many complex problems, there is no single best or definitive strategy. And so, with that in mind, this week we thought it might be helpful to review some of the current narratives around knee pain with an eye toward those that have a strong or growing evidence base. 

Dial-in Your Diet: Healthy Eating improves knee pain trajectory - the connection between diet and pain of all types continues to gain strength. There appears to be a particular benefit for knee pain sufferers who get adequate fiber. Whether it's this 2017 study, which showed between 24-44% lower odds of experiencing moderate or severe knee pain for those who consumed the most fiber, or this review from a few months back, which included more than 30,000 people over 20 years and showed a 27% risk reduction for those who got enough fiber, the connection is worth our attention. For those wondering "how much is enough?", the research team found that the benefit started between 14 and 27 grams per day. To provide perspective, this equates to only a few servings of common fruits, veggies, nuts, seeds, or legumes as listed here.

Out with the Old: Exercise (and yes, even running) helps - The old narrative, that running is somehow "bad" for the knees, thankfully, seems to be on the way out. A few years back, one review was inconclusive at best, with some data showing the repeated and rhythmic joint loads of running actually had a protective effect. Then, last year, another review concluded there wasn't a link between common forms of physical activity (including running) and disease progression. Yet another, which surveyed 37,000 marathoners, found the usual suspects (a history of hip/knee injuries, advancing age, family history, and body mass index) added risk, but years running, number of marathons, weekly mileage, and average pace were not predictors. In fact, just last week, an extensive review that compared a variety of exercise types to determine which was best found that aerobic exercise, which includes running, outperformed the rest. 

More than "mass" alone - For years, we've known that elevated body weight (usually measured by body mass index, a weight-to-height ratio) is related to knee pain and OA. The compressive forces at the knee during even routine daily activities like climbing steps can near the injury-risk threshold when we are carrying extra weight. However, a more nuanced narrative, that it's not only our weight-to-frame ratio that matters, but the source of the weight that counts, is emerging. This 2024 review showed that both muscle mass index (a ratio of muscle mass to height), as well as sarcopenic obesity (i.e., both low muscle mass AND excess bodyweight), were related to knee OA, but low muscle mass without obesity (sarcopenia) was not. Of course, this was not a perfect review (as pointed out in follow-up commentary here), but it provides an interesting new vantage for those of us trying to ease the knees - lose the weight if able, but stay strong.

There are, of course, many others, including regenerative therapies and approaches to whole body inflammation that should be on the radar, but staying strong, feeding on plenty of fiber, and maximizing movement remain near the top of the list.

Have a great weekend,
Mike E.