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GENIE72 SparkPoints: (1,874)
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6/18/14 12:42 P

I knew there would be controversy over this post. As for, it clearly states under the authors name that the article was reviewed (fact checked) by a board certified physician; additionally, the information is supported by eight references to reputable studies in the field. That makes it reliable regardless of what website, newspaper or comic book it is published in.

My intent was to offer encouragement to the people that practice fasting and are feeling pressure to abandon it; or feeling like there is something wrong with them. They now know where to look to find the facts and make their own informed decision. There are a lot of proven (there's that word again) benefits to intermittent fasting, including improved cardio, cholesterol, and preserved lean muscle mass, along with weight loss. Proven is backed by facts, not opinion. If you run a red light it is 'proven' you increase your chances of being involved in a traffic accident. That is not opinion.

My point with the dietitian is that this person is looked upon as an expert in the field by lay persons. This is a misconception, they are not experts, academia only recognizes Ph.D.'s as experts. Dietitians have opinions, that's just the way it is.

You are correct that peer reviewed means just that - it has been reviewed by your peers, and not all of them will have duplicated the study, but the study must have the capability of being duplicated. If duplicated and your study is flawed your peers will hold your feet to the fire and possibly discredit you. As for the null hypothesis; There are abundant studies showing that overeating and obesity leads to deteriorated health and promotes disease. Few would question this.

Thank you for your response. I am three years into a Ph.D. program and I didn't realize this was going to be a peer reviewed post. I am now done debating what peer review means, offering an explanation of empirical data, and explaining what constitutes an expert in the field. I will not respond to or make further posts in this thread.

ANARIE Posts: 13,034
6/18/14 12:40 A

It's good that you're encouraging people to look at peer-reviewed research, but...

"the information is peer-reviewed (meaning it has been successfully reviewed and reproduced by other scientists and proven to be factual and sound"

This actually is not what peer-reviewed means. You might want to double-check your understanding of the peer review process. You're right that we should give much more credibility to material that has been through peer review, but it's a mistake to believe that all peer-reviewed studies have been replicated. Replicable is not the same as replicated. And if you're starting on a research career-- and it sounds like maybe you are-- it's a good idea to try to erase the word "proven" from your vocabulary. "Proven" is an opinion. Researchers reject the null hypothesis.

"As for the dietitian being horrified - she/he does not have a Ph.D. and therefore her opinion is just that - an opinion. It is always advisable to defer to the expert in the field, the research scientist who has studied and analyzed the data"

PhD research scientists are not the only people who do research, and NO ONE who does research would accept the words "always advisable to defer." Research scientists-- successful ones, anyway-- understand that action research, observational studies, and case studies have value and in some situations are the only type of research that ethics allows and/or the only type that's feasible.

And... About dot com? You do understand that is a pay-per-click content farm, right? They don't even have copy editors, much less editorial review. You completely undermine your own whole point with that one URL.

You're doing a good thing by encouraging people to look for research rather than opinion, but that obligates you to be extremely careful with your own words and empiricism.

GENIE72 SparkPoints: (1,874)
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Posts: 64
6/17/14 1:26 P

There is actually a lot of research dedicated to fasting. These papers are peer-reviewed and backed with extensive scientific research. As for the dietitian being horrified - she/he does not have a Ph.D. and therefore her opinion is just that - an opinion. It is always advisable to defer to the expert in the field, the research scientist who has studied and analyzed the data.

If you want more information about the benefits of temporary fasting, you should research the subject ensuring the information is peer-reviewed (meaning it has been successfully reviewed and reproduced by other scientists and proven to be factual and sound). ANYTHING written that is not peer-reviewed is simply opinion, and everyone has an opinion.

A good place to start for peer-reviewed articles would be . You can also google 'peer reviewed articles' to find websites dedicated to scientific research on a variety of subjects.

I truly hope I have not offended anyone with this post. But it is a pet peeve of mine when opinion is touted as fact when it is actually fiction. Just because someone thinks it, does not make it true, only sound scientific research data is fact, everything else is conjecture and opinion. What you read in non-scientific newspapers and magazines that do not offer cited works by reputable scientists is only the authors opinion. I would not accept nutritional information from a magazine that also tells me what the new fall fashion colors will be.

Here is a good place to start:

Edited by: GENIE72 at: 6/17/2014 (13:54)
6/17/14 12:00 P

One of the concepts in the 5/2 plan is that mixing up one's calorie intake doesn't let the body get used to a set number. If you drop your calories down to 1400, you may lose weight initially because you had been eating 2000, but your body will get used to the 1400 soon enough and that will be your new set point. You'll have to exercise harder or restrict further to break that plateau.

The 5/2 argues that eating 2000 most days keeps the metabolism higher and that the 500 calorie days mix it up enough to lose weight consistently while in weight loss mode. I'd like to argue that it's not true fasting--there are some nice sized meals on those 500 calorie days. It is certainly low calorie but not true fasting--think of them as high veggie days.

This program is also bolstered by the data we have on carb cycling--a very similar concept that no food group is cut out but simply cycled so that the metabolism does not tank and you stop losing weight. (Ex: Cheat to Win says to have two low carb days a week and one high one, The Fast Metabolism Diet cycles through 3 phases each week--varying carbs not calories. No food groups are cut.)

If you do same thing and eat the same thing for months will signal your body to get used to it. The 5/2 is actually a moderate approach to diet for people whose bodies tend to get stuck at a set weight point or no longer respond to cutting calories. Please don't freak out with the term "fasting days"--think high-volume Vegetable w/Protein days. This is promoting more calories per week than most diets out there.

SCIFIFAN Posts: 1,119
1/30/14 12:53 P

I have been doing a variation of the 5:2 diet for about 4 months. My variation (which I found in Reader's Digest) allows 650 calories on the two 'down' non-consecutive days a week and 1500 on the other days when trying to lose weight.

I lost about 15 pounds in two months. Right now I am doing only the two down days and eating what I want (within reason) the other days, but will go back to the 1500 calories at some point.

I'm doing the 650 calorie days because I found 500 way too restricting. Yes, it is probably better to just eat fewer calories every day and aim for consistency, but for some reason I find that harder to do.

Since I am at a normal weight (5'3", 130) losing more will be slow, which is ok. I did gain 3 lbs. in December because we were on a 17 day cruise, had Christmas, a birthday, an anniversary and house guests for a week. I did not restrict eating that month except to try not to go crazy with food.

I am holding steady at 130 without further 'dieting', but would like to get down to 115 because of my height, age and small frame. I am also exercising.

Different plans work for different people, and this is working well for me. I actually enjoy the 'down' days and figuring out what I can eat that fits in the calorie limits and is (mostly) healthy. I do tend to eat much the same things those days. A couple of fruits, 3 veggies, some protein, few carbs, and a treat or two--popcorn, one small dark chocolate.

SCOOTGIRL88 SparkPoints: (70)
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1/30/14 11:56 A


I've been on the 5:2 Diet since October 2013 and I've lost 7 lbs at last weigh in. You don't lose pounds quickly, but you do lose. On the fasting days, the key is to drink lots of water or tea. That way you don't feel so hungry. Your body will get use to it and it will get easier as time goes on. Then, on your non-fasting days you'll find yourself eating less. You just don't get as hungry. Good luck!

SPARKLE883 Posts: 148
1/30/14 11:20 A

I think this could work for some people, but I think probably just developing and stick with a consistent calorie intake would ultimately work better. I think as far as improving one's metabolism, consistency is key, and the 5:2 method would likely disrupt the body's ability to adjust its metabolism correctly or effectively.

That said, I have no background in nutrition or medicine - this is just my two cents!

BEEZKNEES Posts: 216
1/30/14 11:06 A

I've been quite frustrated for quite a while with my inability to stick to a diet. Recent attempts have been Whole 30, Body For Life, and calorie counting. Last night, I sort of came up with the idea of intermittent dieting on my own. This morning, I Googled "intermittent carb restriction" and several links later, found the 5:2 Diet. (For the record, it IS backed up by studies.)

To me, this seems totally doable. I don't do well with long term deprivation. I think I could hang in there for 24 hours if I knew that at the end of it I could have what I wanted. The trick will be to not go crazy on the off days.

EELPIE Posts: 2,700
1/27/14 3:52 P

lol...what are food pyramid nazis??

BRINGYOUROWNSUN SparkPoints: (2,297)
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1/27/14 3:39 P

I find it interesting how many people have jumped on the bandwagon to bash this method. I suspect it is the food pyramid nazis in action here.

I have been doing the 5:2 diet off and on for quite some time. And i have to say it is the only method that has ever worked for me. I tried the 'moderate eating' nonsense, the portion controlling crap, all the deprivation diets, the high veg diets, low carb diets, hypnotherapy, cbt etc. and i must say that NONE of them ever worked for me. Not only could i never stick to any of it, but i would just go off these supposed 'sensible eating' regimes and regain all the weight ...and then some.

What i like about the 5:2 diet is the flexibility. I can move my diet days around my life. I can eat whatever i want on my 'off days' and i dont ever bother to count calories... Another mind numbing exercise for people who have far more time than i do. This way of eating simply works for me. I have lost and kept off 40lbs now for over a year and it has required almost no effort.

And just for the record, if you do the diet properly, as in stick to your 500 calories on your two days, your appetite decreases and you arent sitting around starving.

And another thing, if fasting is so bad for you, why have all the major religions, including christianity, encouraged its practice? The religious devout never died from this practice - if you believe the bible, Christ survived 40 days of fasting - nor did they suffer from ill health as a result. This is two days per week... Not anorexia people.

There have been plenty of studies that show calorie depravation and in fact fasting itself prolongs life... Read the research and see for yourself. It shows that calorie deprevation of less than 700 calories... Thats right 700... increases your lifespan. So all those horrified dieticians need to brush up on the current research and get a grip. Our sensible diets are killing us.

EELPIE Posts: 2,700
1/20/14 11:31 A

Scootgirl, good for you!! I don't endorse "diets", but sometimes there are people they work for, and I'm glad it's working for you!

Hope to see you around here again :)

RENATARUNS SparkPoints: (4,367)
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Posts: 1,379
1/20/14 5:31 A

Too inflexible and probably too self-deceiving for me, though I see the appeal. "Just" diet severely these two days a week and you can do whatever you want the rest of the time and still lose weight! Well yeah -- if you do manage to eat at maintenance for the five days, and do manage to eat some 1500 daily calories below it the other two, then you will in fact lose just about a pound every week, all else being equal. But there's no inherent incentive in the plan itself to actually stay at maintenance for the five days -- many will fool themselves that they don't need to, and hence lose only extremely slowly or not at all (or even gain, in the extreme cases). Going so low on calories for two days could even, for some people, increase the risk of backlash binging on the others, that might not have happened if they were going for 1500 or 1700 calories every single day instead.

And as for the two days, what about life? Every single month I go through a period of 2 or 3 days where I just get the crazy munchies and would eat all day if I wasn't paying attention -- if that fell on a fast day I'd lose my mind. As has also been pointed out, how to make intense exercise work with such a plan? What if you're planning a fast for a given day, and then you're invited out to a rare lunch with your work colleagues? You're supposed to just sit there surrounded by other people eating and sip your water? Or you refuse? Or you "give in", and whoops, there goes your entire loss for the week. Or you decide hey you'll do it tomorrow instead, but then your mother is coming for dinner, and you already planned for your more normal menu and oy. Not flexible enough for me by a long shot.

My bias here is strong -- I dislike almost all of these "simple" prescriptions for weight loss success that try to bypass the fundamental issues of calories/portions/eating foods that are good for you. I think they are likely to be counterproductive for most people and would never believe them a good first option, only when the aforementioned methods have been given an honest try and failed, the person knows why they failed, and believes a given method will sidestep his or her particular problems.

SLIMMERKIWI SparkPoints: (205,686)
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Posts: 24,786
1/20/14 2:36 A

My son and his friend tried it, but they gave it away after about 3-4 months. My son likes to work out at the gym 4-5 nights a week and he found that he NEEDED the nutrition for that, but the days he didn't go to the gym, if he was on the restricted calorie day, it was too hard because he also needed the higher calories, as a lot of those who exercise strenuously do, the day after. He started to get a bit weak. He DID lose weight, but that isn't a healthy way to do it.

When I told my Dietitian what he was doing, she was HORRIFIED and told me "Not a good idea!"

You are better off to eat the daily average of that week's calories to ensure that you body gets the energy to sustain it on a regular basis.


SCOOTGIRL88 SparkPoints: (70)
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1/19/14 9:50 P

I have been on the 5:2 diet since October 2013 and I've lost 7 lbs. I'm physically disabled from birth, born without limbs. I know this diet works and it isn't hard to do, once you get use to it. I don't starve the 2 days I fast, because I drink lots of water, or green tea and eat a sensible dinner (500 calories or less). This is the only diet I have ever been able to stick with and accomplish weight loss. It has become a part of my life style. I feel so much better about myself! I tell anyone who says they want to lose weight about this diet, because I truly believe in it. You don't lose weight fast, but it does come off. You don't have to buy special meals, shakes, or pills (that are usually dangerous and cause more harm than good), I don't have to pay any membership fees either emoticon . Can't get any better than this!

MEGAPEEJ Posts: 732
7/29/13 11:37 A

Someone did the math on here one time and showed that if you eat 2000-2500 calories those 5 days and minimal to nothing those 2 days, it averages out to 1450-1800 calories over 7 days. So it's basically another diet "trick" to restrict calories. Isn't it just easier to eat 1450-1800 calories all the time anyway, rather than deal with blood sugar issues and crazy hunger 2 days out of the week?

ANARIE Posts: 13,034
7/29/13 11:13 A

It's the latest fad diet. It's probably fine for people who gained a small amount of weight recently from a very specific event and just need to take off those few pounds and go back to their normal routine. If you've been overweight for more than a few months, though, it's probably not effective or healthy. The diet is based on the idea that you eat "normally" on the other 5 days, but that's not the way most people will actually do it. Those of us who have long-term weight issues have them largely because we balance low-calorie and high-calorie days naturally. If we eat very little one day, we instinctively make up for it the next, but if we eat high calories one day, we don't instinctively eat less the next. In earlier times of human history, that would have made us the healthy, strong ones, but now it makes us fat.

One of the problems in weight loss medicine is that a lot of the "experts" are people who either never had a weight issue themselves or only had one briefly-- they had to lose baby weight or they gained 30 pounds in medical school or something. Then they assume that everyone else's weight problems are the same as theirs and that their approach will work for people whose problem is actually quite different. They don't separate overweight into acute vs chronic the way they do with other health issues.

So if you're acutely (suddenly) overweight, this might work. If you're chronically overweight (it's been going on for years,) an approach that has you counting calories or otherwise keeping track of what you eat at all times is probably going to work MUCH better.

Edited by: ANARIE at: 7/29/2013 (11:15)
IDIOTSAVANT SparkPoints: (0)
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7/29/13 11:01 A

Well, this is just more evidence that NPR is just as sloppy as every other major new organization. Did they tell you how it is completely unsupported by scientific evidence? Did they tell you that other approaches work well that don't require starving yourself two days out of the week? Did they have any opposing viewpoint that told you these things or was it a puff piece to fill times between the corporate sponsorship messages (that aren't ads!)? Did they tell you anything that suggested that is is more than just the latest fad designed to get ratings for some radio program?

SANJO1996 SparkPoints: (159)
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7/29/13 10:51 A

Has anyone heard of the 5/2 diet? Supposedly you eat normally for 5 days and then for 2 days you eat very little and only lean protein. I heard them talking about this on the radio this morning and it was the first I heard of this approach.

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