SEARCH My Blog (Opens in new tab)
Exercise and healthy food count but there's an unexpected twist
Scientists are increasingly discovering that the changes in the circadian rhythm as we age are associated with reduced longevity.
Normal, healthy aging is associated with a weakening of the circadian system. The first indication of damping of circadian rhythms with advancing age came from studies by Franz Halberg in the 1950s, on mice. We now know that circadian rhythm plays a vital role in health, and prolonged clock disruptions are associated with chronic diseases.
Knowing how to boost strengthen the circadian rhythm may yet turn out to be as important as strengthening our muscles, for longer life.
Not just what we eat and if we exercise
As is so often the case, it turns out that a sedentary and poor-nutrition lifestyle induces a disruption in circadian rhythm, thus promoting an increase in pro-inflammatory "factors". This increase raises the level of chronic low-grade inflammation as we age. Unfortunately, that makes us more vulnerable to succumbing to coronaviruses, for example.
We might expect that being active, that is, not being sedentary, and eating better food would naturally be of benefit to our health, including our circadian rhythm.
Perhaps unexpectedly, it turns out that how we eat has a strong effect on our circadian system, perhaps as much as what we eat.
When, counts for as much as what we eat
Time-restricted eating (intermittent fasting) enhances our ability to maintain a robust circadian rhythm. A strong circadian rhythm is positively associated with healthier metabolic aging, e.g. a stronger immune system and with living longer better.
As compared to mice who ate at liberty, mice fed during the first 4 hours of the light or the dark span had a larger circadian amplitude. (As measured by such things as body temperate, corticosterone, and liver glycogen). In this and subsequent studies, the amplitude of circadian rhythms was generally increased when food intake was restricted to a single daily meal.
If our "circadian amplitude" is high, it means that our body is optimally managing its energy balance the most efficient way possible. This means (among others) the proper distribution of resources e,g, blood and hormones to support functions most appropriate for a given time, e.g. rest and recovery during sleep.
A low circadian amplitude means that our body is constantly assigning resources in a suboptimal way. It is never focusing on getting any one job of repair, digestion, regeneration, or molecular scavenging done properly (nor the million other things that it has to organise in one 24 hour period).
In other words, our body performs poorly when continually multitasking.
We want to boost the power of our circadian rhythm and reap the rewards of our body being better able to marshall its energy in the right place and the right time.
How can you implement time-restricted eating, and should you eat less?
Lower caloric intake is associated with a longer life span in Okinawans, as well as with reduced body weight, blood pressure, blood cholesterol, and blood glucose - variables related to major killer diseases.
Some studies have found a greater weight loss for a "breakfast only" plan of intermittent fasting than "dinner only". This outcome reconciles with circadian variation in diet-induced thermogenesis, which is higher in the morning than in the evening in healthy people. That means that you burn more calories digesting your breakfast than your dinner.
But it is difficult to change too many things at once; you will probably fail at them all.
So rather than confusing time-restricted eating with weight loss I recommend that you simply alter your meal timing first, and get used to that, before thinking about also restricting calories.
Luckily, time-restricted eating has become a topic-du-jour, and there is a myriad of trustworthy sites with useful advice on how to get going:
The point about it is this — by starting today and building some of the time-restricted eating principles into your eating habits, you will feel the benefits quite quickly. And over time, as well as improving your overall metabolic health, you are also more likely to retain your brain health and cognitive abilities.
Keep it simple
If you want a short-cut to getting started, here's what I did to get going with varying my eating times:
The most important thing is to find a pattern which works for your lifestyle and stick with it. Build on that.
PS Don’t throw out the bay with the bathwater - what we eat is obviously very important for aging well. Recent studies have even established that polyphenols can modulate the composition of core gut microbiota and interact benefitically with our circadian clocks. So keep eating plenty of vegetables and enjoy regular cups of tea.
> More posts to help you with EXERCISES
> More posts to help you with DIABETES
> If you are a @MEDIUM reader my publication Body Age Buster has hundreds of categorised posts which I have written especially for men and women over 50.
Latest: get your free customised fitness plan designed uniquely for you.
Since I was diagnosed at 50 with Type 2 diabetes I've been learning how to do bone-building fitness training which lowers my age. You can too. It's your choice. Walter