About a year ago, I began to notice that my knees sometimes hurt when I went down stairs (I live on the third floor (US)/second floor (UK)), but I didn’t pay too much attention to this - it wasn’t particularly painful, but it was something. Everyone has a certain mind-body constitutional make-up with unique areas of resilience and weakness - and for highly vata people like me, joint problems are not uncommon. This is because high amounts of vata - associated with air and space - can dry out lubrication in the joints. So, for example, my knees have clicked when I crouch down since I was a teenager, painless, but embarrassing!
Anyway, back to last year...later in the year, a volunteer at a community garden I was involved with mentioned she could tell whether it was raining out just by how her knees felt. Now, I’m sure you may have heard of older people complaining about this, but neither of us were remotely near that category, so I made a note to see if this happened to me. But last summer turned out to be first proper summer in England in a long time - it didn’t rain until some time in August.
Sure enough, on those rainy days, I realized that my knee pain on the stairs wasn’t random at all - I only had it on the rainy days. By accident, I also discovered a way to avoid having it. One day, I ate breakfast much later than usual - it ended up being more like a brunch. This was not deliberate, it just happened. On that rainy day, I didn’t experience any pain when I descended the stairs. Pondering what was different, I realized that I had inadvertently extended my overnight fast from 12 hours to something more like 16 hours. Of course, one day could just be chance, so I made a note to do an experiment the next time we had a prolonged stretch of rain - this being England, it was bound to happen at some time. I had to wait a while, but it happened - it was the first time I looked forward to weeks of continuous rain.
Happily, following the days I did a 16-hour overnight fast, my knees were fine on the stairs; 13-14 hours of fasting wasn’t enough. Everyone is different and has a different internal ecosystem, so effects of fasting will vary. For some people, an even longer overnight fast might be better. Moreover, not all joint pain is linked to rain. However, beyond my own personal experience, research is building up on the impacts of intermittent fasting on inflammation (which is a factor in nearly every chronic disease), detoxification - via autophagy (a way the body cleans out damaged and dead cells) and ketosis (which increases glutathione, a detoxifying agent), appetite and blood sugar regulation, and the body’s stress response (Longo and Mattson, 2014; Tello 2019).
Fasting is useful both to preserve health if one is fairly healthy, and to help improve health for those who may have particular problems. Yet it is not right for everyone, and at any rate, it’s best to try slowly - perhaps extending the overnight fast an hour at a time - and see how your body responds. If you’re not already doing a 12-hour overnight fast, then that’s a good practice that is fairly safe for everyone. This would look something like stopping food and drink intake (except for plain water) by 7pm and then not eating or drinking 7am.
The usual cautions exist - if you’re on medications, discuss with your doctor first. It’s also not something one should try while pregnant or breastfeeding.
Tello, Monique. Intermittent Fasting: Surprising update - Harvard Health Blog. June 29th, 2019. https://www.health.harvard.edu/blog/intermittent-fasting-surprising-update-2018062914156
Longo, V.D. and Mattson, M.P. (2014) Fasting: Molecular Mechanisms and Clinical Applications Cell Metabolism 19(2): 181-192