Fasting and Its Metabolic Effects - Counterintuitive Perspective [Dr. Steven Phinney]
Now, there's a lot of hype about fasting at the moment. And there are some folks that go against the proverbial grain. One of these people is Dr. Steve Phinney, a very popular figure and researcher in the field of ketogenic diets.
Steve Phinney together with Jeff Volek wrote two books that have been very read by folks in the keto community: The Art and Science of Low-Carbohydrate Living and The Art and Science of Low-Carbohydrate Performance. These books have been on my reading list (on top of it) when I started experimenting with the ketogenic diet a few years ago.
Anyhow, there's a general trend of promoting fasting and intermittent fasting as two practices very healthful for people. And the common dogma is that they are good for anyone at anytime. Professor Phinney draws some exclamation marks for these practices, but mostly for extended fasting.
And one of his motivations is that it permanently reduces basal metabolic rate, along with other potential negative effects. To be honest, I dont completely agree with Prof. Phinney, but I'm glad that we, at least, some contrasting perspective on this. Please watch the lecture below for the full scoop.
The data this guy uses is pretty old. Even though hes says that they have stood the test of time.................. this puts into question a lot of theory.
That being being said there several interesting point in this presentation. When he talks about BMR at around 4 minute mark the drop noted at around 30 day mark is 25% (which is huge). What I found interesting is that BMR went up in lean people in first 1-2 days.
What I want call in question here is the assumption that people would fast for days on end. This seems like an extremely marginal action. In fact I have never ever met anybody who subscribes to the idea of total fasting. Even Muslims, when they fast for a month, would break the fast in the evenings and then restart in the morning with a light meal.
Around the six minute mark he also mentions that the gradual decline in BMR over extended periods is not protected by the presence of extra body fat. This is actually quite reasonable, as fat reduction can only occur by a sustained routine of controlled diet intake and exercise (maybe a little fasting thrown in as well).
He also makes some really good points on protein metabolism.
The only person I know that subscribes to the idea of total fasting is my dad. So, I would agree that it is really a marginal action, but not an action that never happens. Even though muslims do break their fast, I think this idea of total fasting stems from religion in most cases. I don't see how anyone could realistically believe that it is a good and worthwile means to lose weight. The negative side affects are just to substantial. I can say that it definitely did work for my dad, but of course going 30 days without food would cause weight loss. I would dissagree wholeheartedly if he told me it was a healthy way to lose weight, though.
Not necessarily religion. In 90's the fasting was the most prescribed ways to loose weight, until more prominent research came out with the benefits of controlled diet as opposed to abstinence.
I agree that extended fasting may reduce metabolic rate perminantly, or at least more perminantly, but intermittent fasting really doesn't provide a long enough fasting window to perminantly damage the body. For thousands of years humans had to cope with terms of fasting. Not for long periods of time over 48 hours as Dr. Phinney says. Humans evolved around short periods of fasting while they searched for quality nutrition. It would make sense that humans should then have evolved to thrive in their environment of short fasts between finding food.
I would probably agree with Dr. Phinney in his thinking that long periods of fasting are probably unhealthy. This really doesn't start cropping up in humans until long ceremonial and religious practices started to spread. All in all, old data really isn't always the best as @hashchash said. I would definitely like to see some new work on this. Old data just wasnt heald to the same standards as we currently operate under in the medical field.
Great Post! Resteemed!
Many things got cleared with that video and really got to learn a lot more than i expected excellent video thanks for sharing that :)