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Transcript: Intermittent Fasting: What is it? Recommend it? Part 3

This is part 3 of a 3-part video transcription.

Transcript Part 1  |  Transcript Part 2 


To view the video series, go here.


Steve Freed:               Right. So are there any books available that people that want to go on a diet that they kind of explain what to expect and so forth?


Dr. Mark Mattson:     Yeah, there’s a lot on the internet now that’s easily found by putting in intermittent fasting – if they just put those two words – into Amazon – not that I’m endorsing Amazon but everybody knows about it – you know, they sell a lot of books there – so there’s this five-two diet – two days a week fasting – and that started based on studies we did with Dr. Michelle Harvey at the University of Manchester, we published studies with the five-two diet and women at risk for breast cancer and showed that it reduced markers for risk for breast cancer and improved insulin sensitivity and so on.

But then there’s an MD/producer at the BBC that picked up on this – a guy named Michael Mosley – and there was a BBC documentary on fasting and Mosley himself went on the five-two diet and then monitored a bunch of health indicators and did blood work and so on and showed that it’s risk factors for cardiovascular disease and diabetes were reduced. And then he wrote a book called The Fast Diet. Then Dr. Michelle Harvey wrote a book called The Two-Day Diet so those are both on this five-two diet.

And then there’s a couple books on the time-restricted feeding approach that is eating something each day but limiting the time window that you eat the food. one’s called The Eight-Hour Diet.


Steve Freed:               Is there one in particular that follows your strategy and that you would likely –


Dr. Mark Mattson:     Well, The Eight-Hour Diet kind of does.


Steve Freed:               And what about the five-two diet?


Dr. Mark Mattson:     Yeah, I personally don’t do that but that’s – because some people find that easier to fit into their weekly routine. And I think both are effective in improving health.


Steve Freed:               So let me ask you a question. If you went to the lab and had an A1c test done and it came back and you were pre-diabetic what would you do? Exactly what would you do?


Dr. Mark Mattson:     Well, I’d be pretty surprised because I’m already doing what I would do.


Steve Freed:               Okay.


Dr. Mark Mattson:     But I understand what you’re saying, it’s a hypothetical. Well, I would definitely reduce food intake. With my knowledge of the science of it I would go on an intermittent fasting or time-restricted feeding diet and I would start exercising, and if I’m already exercising maybe lightly exercise more – vigorous exercise.

You know this is – an extension of this work is – and we really need to test this in rigorous studies – is that it may be better from a standpoint of preventing diabetes to do your exercise after you haven’t eaten for an extended time period.

You know some people will exercise early in the morning and that can be good if they’re already healthy – and so then they’ve fasted for at least eight hours – presumably the time that they’ve been sleeping or a little more – and then exercise.

From a physiological standpoint you can even get a better improvement in insulin sensitivity and – so the glycated hemoglobin is kind of a measure of your glucose levels over a long time period, and so I would expect that if you fast for say 10, 12, even 16 hours then exercise that’s going to move your markers – risk factor markers for diabetes in a good direction, more than say if you get up and eat breakfast and lunch and then exercise and then fast after that. I think it’s better to eat right after you exercise because then the nutrients are – glucose and amino acids – are taken up readily into your muscles and that’s important for building muscle and maintaining muscle mass.


Steve Freed:               You know one of the things that I’ve noticed, and I had a chance to ask six physicians – general practitioners – if they heard that the intermittent fasting can help with all these issues, and all of their patients had one of these issues that you mentioned.

And they were not even aware of intermittent fasting. You know, they’re busy in their medical practice, they don’t get to read all the journals, you know, so the word is not getting out there. You know, I think that’s something that we need to probably change – even though there aren’t a million studies out there I mean eating less is – it’s just like exercise, you know, exercise is good – we all know exercise is good – eating less is good – we all know eating less is good if you’re overweight – you know, but somehow the word doesn’t get out there.


Dr. Mark Mattson:     Yeah. Well, I think with exercise – you know, there’s been a lot of data for a lot longer. The other thing is there are industries that do make money with – you know, for exercise. So there’s health clubs and fitness centers that – and you know for many people that’s a – that really helps them get into and stick with an exercise routine.

So the physicians are definitely aware of the importance of exercise. And you know these eating patterns and intermittent fasting – the word just hasn’t gotten out there yet, and it’s important that it does.


Steve Freed:               My last note is that what if a drug company came out – and we already have certain items that block cholesterol and we have drugs that can block carbohydrates – why not just come out with – even though it’s ridiculous because it’s going to cost $600.00 a month – to come out with a drug that blocks the absorption of calories?

Dr. Mark Mattson:    Yeah, there is some work in that area. You know if there was a safe appetite suppressant that one would take – so for example you take it when you get up in the morning and then you’re not – like the half-life of the drug is such that you’re not hungry until mid-afternoon or something, then you know people could not eat breakfast or lunch and not be hungry, and in theory if there were no side effects that would seem to be something that might work.

However there’s not any such drug and, you know, the things that have been tried so far are not very specific – they’re like amphetamine like drugs that lead to bad side effects – for example cardiovascular side effects – but if there’s some specific drug that could suppress appetite without having any untoward effects that might be one approach.

Blocking energy uptake in the gut – calorie uptake – there have been some things that have been tried but people would have diarrhea and you know the drugs were such that they cause a lot of GI side effects.

Another approach would be to – we think that in part the mechanisms whereby intermittent fasting benefits health is that it imposes a mild stress on cells in the body and the cells respond adaptably by enhancing their ability to cope with more severe stress and resist disease.

And so for example in the brain we find that both exercise and fasting increase production of proteins that are called neurotrophic factors or they promote a growth and stress resistance of neurons.

So we’re working on – actually have some efforts to try to identify chemicals or drugs that can activate these adaptive stress response pathways and protect cells against things like oxidative stress and inflammation.


Steve Freed:               I want to thank you for taking the time. And I have to make a request of you, and that is as new research comes out – because I’m sure, you know, living longer is a good thing and people are interested in it, and doing it with a quality of life is the important thing – so as your research goes forward or if you hear of any kind of other research that I can publish or at least do a summary on and pass it onto our medical professionals that would be great.


Dr. Mark Mattson:     Okay. I will.

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