I believe fasting can help you loose weight because you are eating less calories over all. However, i’m skeptical of the added health claims made by Michael Mosley. If you are overweight and then loose weight you’ll likely see improvements in your blood work etc indicating a reduction in lifestyle related risk factors. I’m not convinced this is due to fasting itself, i think it’s more likely due to the weight loss and you will see health improvements if you loose weight, no matter how you loose it.
The book seems to be implying that fasting should be a lifestyle choice for everyone, not just a diet for obese people, which will result in us all living longer and healthier lives. But these are big claims which lack the scientific evidence to back them up.
I was reading that the researcher whose work the book is based on has complained that her work has been misrepresented:
‘My research on alternate-day fasting has been misrepresented in the book,’ Dr Varady told Healthista in September last year. ‘Mosley used my research, which looks at fasting three to four days a week, to support his diet, which encourages fasting two days a week.’
“The Fast Diet is about his [Mosley’s] experience,’ says Varady. ‘But unfortunately he actually used all of my research on alternate day fasting to support all of his points. Scientifically you can’t take studies that look at three or four days fasting a week like mine and say it’s the same thing and that you’re going to get the same health benefits when you just fast two days a week.’
http://www.healthista.com/nutrition/fasting-diets-krista-varadyscience-research-studies-52-diets/
And there is also this excellent review of The Fast Diet book which looks at what evidence there is to support it. Spoiler alert: There’s not much.
“Putting aside the fact that many of our closest primate relatives do in fact graze all day (chimpanzees for instance), I’m not sure this theoretical line of reasoning really matters in lieu of evidence, though certainly it does provide a reason to consider the possibility that fasting has interesting properties.”
“When The Fast Diet does venture into evidence based research the bulk of it comes from mice and rats – useful models to start with no doubt, but of course results from rodent studies are not automatically translatable into humans. One of the book’s primary theories is that fasting is helpful because it reduces circulating levels of IGF-1 (insulin like growth factor 1) which in the case of a particular strain of mouse, might be implicated in many disease processes including aging and cancer. And while I am by no means an expert in intermittent fasting or IGF-1, it strikes me as odd that in the few studies I found on medline that specifically looked at IGF-1 levels and intermittent fasting in human subjects following the ADMF protocol espoused by The Fast Diet, there wasn’t a consistent effect on IGF-1. One study I looked at showed a decrease in IGF-1 only when energy restriction was accomplished by means of a 10 week liquid ADMF diet, while the other, actually showed little change or even a small rise in IGF-1 levels following a full 6 month trial of ADMF dieting by overweight women. But rather than report on the effect one of the longest and largest trials of ADMF dieting in overweight humans that showed no change to circulating IGF-1 Dr. Mosley chose to report on his own personal drop in IGF-1 levels while following his diet – an odd thing considering the randomized trial he didn’t cite was in fact conducted by Dr. Krista Varady – the researcher responsible for The Fast Diet’s actual regimen and one of the book’s most regularly featured personalities.”
“”Dr. Mosley’s section covers other purported benefits of ADMF fasting – most propped up almost entirely by theoretical or non-human based underpinnings with his take being that ADMF fasting staves off Alzheimer’s, prevents cancer, improves chemotherapy, lengthens your lifespan, improves your memory, decreases depression, and of course helps you to lose weight and improves your cholesterol.”
“Ultimately here’s a diet book based primarily on theoretical conjecture and mouse studies that’s propped up almost exclusively by the personal experiences of two professional journalists neither of which were obese to begin with nor working with patients trying to manage their weights, where statements such as,
“studies and experience show that intermittent fasting will regulate the appetite, not make it more extreme”
fail to come with citations, and where on the very same page the statement,
“It all points to a healthier, leaner, longer old age, fewer doctors’ appointments, more energy, greater resistance to disease”
coexists with the butt covering,
“yet science is only just starting to catch up”.
So if you want to try fasting as a means to control available energy intake – by all means go for it, but as the authors in rare moments of clarity between wild conjectures and unsupported statements point out, the science is still far too young to be conclusive.”
http://www.weightymatters.ca/2013/04/diet-book-review-fast-diet.html
So, I’m not convinced. As someone with a science background i can see that Mosley has cherry picked studies to support his beliefs while omitting large scale randomized studies which go against him. That’s bad science Mosley. Bad science. No wonder Varady is pissed off.
8:25 am
6 Nov 14