8,000 at 20

(Part 2 of 13 in John Briffa's "A Good Look at Good Health")

Memorize this: “8,000 at 20”

That is: “8,000 steps at a 20-minute-mile walking pace.” I’ll explain below, but first…

The researchers involved in this study then looked at what levels of activity appeared to be associated with BENEFITS for PHYSICAL and MENTAL health. What they found was that improved physical health was seen in individuals taking 8,000 steps a day at [a certain] intensity.

The threshold above which there was an associated benefit for MENTAL health was lower: only 4,000 steps a day at [a certain] intensity.

~ John Briffa, from Walking may be ideal exercise as we age 1

It’s not about how far you walk; Don’t worry about how long your legs are. It’s about how hard you are working when you walk. Basically, you need to do the steps at a level of exertion that is roughly 3 times you base metabolic rate; That is to say, the rate at which your body burns energy when you are sitting still doing nothing. The intensity this research points at is roughly a 20-minute-mile walking pace for average height/legs. This is faster than “I’m strolling” but well below “I’m late! speed walking”.

Just go walk for 45 minutes every day.


  1. http://www.drbriffa.com/2009/06/05/walking-may-be-ideal-exercise-as-we-age/ 

HIT improves… your body’s sugar handling?

(Part 3 of 13 in John Briffa's "A Good Look at Good Health")

In this particular study, individuals engaging in the ‘high intensity interval training’ (HIT) sprinted on a exercise bike with maximum effort for 30 seconds at a time with 4 mins of rest in between. 6 sessions were performed over a two-week period, with 4-6 ‘sprints’ in each session. I was interested to read a recently published study which used an identical exercise schedule. The focus here was not on fitness benefits, but on the impact HIT might have on individuals’ ability to handle sugar.

~ John Briffa, from Short bursts of high intensity activity found to improve body’s ability to handle sugar1


  1. http://www.drbriffa.com/2009/01/30/short-bursts-of-high-intensity-activity-found-to-improve-bodys-ability-to-handle-sugar/ 

The calorie principle

(Part 4 of 13 in John Briffa's "A Good Look at Good Health")

There are a number of potential mechanisms that explain why nuts may not be fattening which were explored in a recent review that appeared in the Journal of Nutrition recently [1]. I’ve summarised them (along with one mechanism that is not discussed but I think is important) below:

Studies show that nuts tend to be effective at satisfying the appetite, which can mean that individuals just end up eating less of other foods. The percentage of calories that come from nuts that are compensated for by eating less of other foods varies from study to study, but comes in at around 70 per cent.

~ John Briffa, from Why the evidence on nuts and weight makes a mockery of the calorie principle 1


  1. http://www.drbriffa.com/2008/10/06/why-the-evidence-on-nuts-and-weight-makes-a-mockery-of-the-calorie-principle/ 

What is “intermittent fasting”?

(Part 5 of 13 in John Briffa's "A Good Look at Good Health")

Quelling insulin will help protect against these conditions, and will facilitate fat loss too. One way to quell insulin levels is to eat a diet largely devoid of the foods that cause surges in blood sugar such as those [of] added sugar as well as starchy ‘staples’ like bread, potatoes, rice pasta and breakfast cereals. Another way, though, to moderate insulin levels is to extend the time between eating. This, in essence, is what intermittent fasting is about.

~ John Briffa, from My Times piece on intermittent fasting 1


  1. http://www.drbriffa.com/2012/03/01/my-times-piece-on-intermittent-fasting/ 

Metabolic advantage

(Part 6 of 13 in John Briffa's "A Good Look at Good Health")

The idea that a particular diet might have weight loss benefits that cannot be predicted utterly by the calories contained in that diet is often referred to as ‘metabolic advantage’. I’ve found it to be a vexed topic, with commentators on it belonging to one of two camps. On the one hand we have those that believe ‘a calorie is a calorie’, and that the form that calories come in have not bearing on their impact on weight. On the other hand, we have those who maintain that the form calories come in can influence body weight in a way that is independent of the number of those calories, or who are least open to the idea that his can be true. Just to be clear, I am in the latter camp.

~ John Briffa, from Is there such as thing as a ‘metabolic advantage’?1


  1. http://www.drbriffa.com/2009/10/19/is-there-such-as-thing-as-a-metabolic-advantage/ 

It looks like our ancient ancestors ate a low-carb diet

(Part 7 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2011/10/11/it-looks-like-our-ancient-ancestors-ate-a-low-carb-diet/

Official recommendations are normally that about 60 per cent of the calories we consume should come from carbohydrate. That’s actually higher than the most carbohydrate-rich hunter-gatherer diet of all, and about three times the average carbohydrate percentage in such diets. The authors of this study conclude, ‘…the range of energy intake from carbohydrates in the diets of most hunter-gatherer societies was markedly different (lower) from the amounts currently recommended for healthy humans.’

Not “low carb” as in some wacky, extremist diet. I’d prefer to call it a “normal carb diet” where you simply try to get your carbs from tubors, fruits and veggies, not from added sugars and refined grains.

Is obesity all in the mind?

(Part 8 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2011/03/10/is-obesity-all-in-the-mind/

My position, and that of a growing number of researchers, is that there’s more to obesity than calorie balance, and that body weight and fat mass is regulated by a complex system that involves an array of hormones and feedback mechanisms.
In recent months I’ve become interested in the potential role of a hormone by the name of leptin in obesity.

It’s not “in the mind” in the sense that you can imagine your way to weight loss. But there’s definitely MORE to weight loss than the balance of calories. My experience is that the best way to lose weight is to simply reduce my calorie intakes slightly — no need to count everything and aim for a computed target intake. At the same time, include some strength training (a ton is not required, but walking/cardio is NOT what worked for me.)

Maybe turn off the TV and go to bed

(Part 9 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2012/07/19/want-to-lose-weight-maybe-turn-off-the-tv-and-go-to-bed/

Six years ago I decided to dramatically reduce the amount of time I spent watching TV, and this single intervention (I believe) had a dramatic effect on my life. It liberated a significant amount of time that I could devote to perhaps more useful and rewarding pursuits. You may be thinking that I’m referring to things like writing or exercise. Actually, I’m referring mainly to sleep.

Sleep — specifically, learning about sleep, fixing my sleeping environment and getting more and better quality sleep — is the SINGLE most important thing I changed in my journey these last few years.

Exercise boosts the metabolism? It seems the reverse might be true

(Part 10 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2012/06/15/exercise-boosts-the-metabolism-it-seems-the-reverse-might-be-true/

However, he went on to talk about a mechanisms here that came as quite a surprise to the audience, I think: aerobic exercise can suppress the metabolic rate. We’re often told that exercise not only increases calorie burn while we’re exercising, and also for some time after. It turns out, that may well not be the case for many people. In fact, according to research, the opposite is quite likely to be the case.

Metabolism, and the human body in general, is very complicated. Excercise turns out to not function AT ALL the way I thought it did. I thought you could just “excercise more” to burn a few hundred extra calories a week and VOILA! L’SKINNY. Nope. Exercise is great! Good for your health, etc. But, at the quantities I do, it is not the driver of my weight loss.

Meanwhile, I’ve spent about 5 years now actively learning about food, biology, health, fitness, chemistry and more… and I’m still convinced I know very little. :/

Study suggests that, for optimal fat loss, the best thing to eatbefore exercise is nothing at all

(Part 11 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2012/11/13/study-suggests-that-for-optimal-fat-loss-the-best-thing-to-eat-before-exercise-is-nothing-at-all/

The concept of endurance athletes stocking up on carbs has, I think, fuelled the notion that we should ideally have some sort of fuel inside of us prior to exercise. However, as I explain here, there is an argument for avoiding spikes in blood sugar is seeking to maximise one’s capacity to utilise fat as a fuel during exercise. I think there’s an argument for consuming little or nothing before exercise unless, perhaps, exercise is to be very prolonged.

Sometimes people don’t believe me when, around 11am in the middle of some crazy physical activity, it comes up that I haven’t yet eaten anything. I usually ask them why they think they must eat every waking hour? Why is “breakfast the most important meal of the day”? Why do you eat what you generally eat? And then I ask them to consider looking into the notions they have about nutrition…

How often should we eat?

(Part 12 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2012/08/31/how-often-should-we-eat-2/

When I started experimenting with intermittent fasting a year or so ago, it occurred to me that my previous beliefs about our ‘need’ to eat three times a day were just wide of the mark for me and, as it turns out, a lot of other people now. I now encourage a much more fluid approach based on the two guidelines above. One thing it’s done for me and others is to liberate us from the supposed need to eat by the clock. The benefits can be huge. In general, taking a more fluid approach seems to lead to people eating less, having more time, and being less preoccupied with food. These are usually big pluses for people.

Vitamin D improves energy production in muscles of vitamin D-deficient people

(Part 13 of 13 in John Briffa's "A Good Look at Good Health")

www.drbriffa.com/2013/03/18/vitamin-d-improves-energy-production-in-muscles-of-vitamin-d-deficient-people/

In this study, muscle function was assessed in a group of 12 individuals with known vitamin D deficiency. The assessment centred around timing the replenishment in the muscle of a substance known as phosphocreatine. Phosphocreatine is a key molecule in the production of energy (in the form of what is known as ATP) by tiny ‘powerhouses’ in the cells of our body known as mitochondria (pronounced my-toe-con-dree-ah). Shorter phosphocreatine replenishment times after activity are a sign of better mitochondrial function.

Vitamin D supplementation was found to lead to a significant reduction in phosphocreatine replenishment times, signalling an improvement in mitochondrial functioning. Fatigue ratings improved in all the study participants too.

The more I read, the more I believe that Vitamin D is a keystone for my health and progress. I believe that getting more sun exposure (walking, running, and Parkour outside), combined with taking vitamin D supplements has enabled a lot of other successes: Better sleep, better immune system functioning, better mood (ever hear of “Seasonal Affliction Disorder”?) and now, some evidence that it really does affect the performance of your mitochondria — your cells little power-houses.