A topic that I love, but haven’t yet gotten to comment on on this blog, is the remarkable health benefits of sauna use.
Over the past few decades, a large body of scientific research has shown that brief exposure to temperature extremes (both hot and cold) can lead to some biochemical processes in the body that promote better health. In a way, this is analogous to intense exercise. During a bout of intense exercise (say, doing sprints or jump ropes), certain chemical processes are upregulated in your body. In the hours after you finish exercising, these processes lead to beneficial effects in your body such as lowering your blood pressure, slowing your resting heart rate, and improving your insulin sensitivity. Similarly, being exposed to 15 or 20 minutes of uncomfortably hot air can lead to changes in your body over the ensuing hours that are beneficial to health.
One of the popular strategies for weight loss over the past decade has been intermittent fasting, or as some researchers call it, time restricted eating.
In case you don’t know what this is, it’s simply setting a restricted schedule around when you eat and when you don’t. Studies have shown that the typical American spends more than 15 out of every 24 hours in a “feeding” state, meaning that they eat shortly after waking in the morning, and then consume multiple meals and snacks throughout the day right up until shortly before bedtime. As a result, the longest stretch they ever go without eating in a typical day is no more than 9 hours, most of which consists of the time they are asleep overnight.
By contrast, somebody who is intermittent fasting might follow one of the following schedules:
In my last post, I talked about the importance of maintaining humility when promoting or dismissing lifestyle interventions for better health. Today I’m going to flesh that out a bit further.
There’s an old joke among epidemiologists that goes like this:
The Japanese eat very little fat and suffer fewer heart attacks than the British or Americans. The French eat a lot of fat and also suffer fewer heart attacks than the British or Americans. The Japanese drink very little red wine and suffer fewer heart attacks than the British or Americans. The Italians drink excessive amounts of red wine and also suffer fewer heart attacks than the British or Americans. The Germans drink a lot of beer and eat lots of sausages and fats and suffer fewer heart attacks than the British or Americans.
Conclusion: Eat and drink what you like. Speaking English is what kills you.
Today’s post will just be some musings of personal observation.
If you follow any online “health influencers,” you will notice that they often attract a rather passionate set of followers and detractors. For example, you will commonly find influencers in the low-carb community (and their followers) denigrating anybody who disagrees with them as not just wrong, but as stupid or corrupt. I commonly see commentary around such influencers that doctors have “lied to” the public about sugar; that the data linking high cholesterol to heart disease is based on only a few flawed studies from the 1950s; and that Ancel Keys (one of the early leading proponents of reducing saturated fat and cholesterol) made up his research results – none of which is true.
On the vegan side of things, one can find the same tendencies. I’ve seen interview clips of Michael Gregor (a prominent vegan physician and author) for example promoting the idea that a vegan diet is the “only” diet shown to reverse heart disease (it isn’t). And as a resident I once took care of a patient in the hospital who refused to believe – despite all evidence to the contrary – that she had had a heart attack, because she was a vegan and “if you don’t eat animal products, you can’t get heart disease.” (In fact, cardiovascular disease is the number one killer of all Americans – vegans included).
A recent study out of Northeastern University (just up the road from here, in Boston) makes a point that I harp on a lot: you can go most of the way toward meeting your fitness needs without any gym membership, without any fancy equipment, and without leaving your home.
I’d like to use this post to introduce a very simple, and important, concept that is a key idea to understanding metabolic health: the “personal fat threshold.”
