A closer look at the excellent work undertaken by Dr. Krista Varady.
Back on the 16th I wrote a post that was a follow-up to the previous day’s post about living a long life. My follow-up was called, hardly surprisingly, Postscript to Long Life post.
In that follow-up post, I wrote this,
Over on the Healthy Fellow blogsite, there’s an interview with Dr. Varady. The web link of that interview is here and crossing over and reading the full interview is much recommended. Here’s a taste, pardon the pun, of that interview:
JP: Can you help explain the distinctions between alternate day fasting and caloric restriction?
Dr. Varady: Caloric restriction is basically daily calorie restriction where an individual would restrict themselves by about 15% to 40% of their energy needs daily. So basically every single day you’re undergoing the same amount of restriction, whereas alternate day fasting involves a fast day wherein the individual would only eat 25% of their energy needs. So about 500 calories or so and that’s alternated with something called a “feed day” where the individual would eat ad libitum – so as much as they want. However in our studies we show that people end up losing weight because they can’t fully make up for the lack of food on the fast day on the feed day.
I’ve been in touch with JP wondering if I might have permission to republish the full interview. Unfortunately that wasn’t possible. However JP did say that republishing a couple of paragraphs would be fine and I’m going to be cheeky in adding a couple to the one I already published above!
Anyway, before inserting those paragraphs, let me set the scene. A very quick web search comes across the fact that Dr. Varady is an Assistant Professor at the UIC College of Applied Health Sciences. Her research work is described thus,
Research Interests
Dr. Varady, PhD
My research investigates the ability of novel dietary restriction strategies to facilitate weight loss and decrease cardiovascular risk in obese subjects. The most common dietary restriction protocol implemented is daily calorie restriction (CR), which involves reducing energy intake by 15 to 40% of needs daily. Another dietary restriction regimen employed, although far less commonly, is alternate day fasting (ADF). ADF regimens include a “feed day” where food is consumed ad-libitum over 24-h, alternated with a “fast day”, where food intake is partially or completely reduced for 24-h. ADF regimens were created to increase adherence to dietary restriction protocols since these regimens only require energy restriction every other day, rather than every day, as with CR. Recent findings from our lab demonstrate that ADF is an effective means of facilitating weight loss and improving several indicators of cardiovascular disease risk in overweight and obese subjects. Our findings also show that changes in adipose tissue physiology during weight loss may mediate these improvements in vascular health.
Current research activities
Developing novel diet and exercise regimens to facilitate weight loss and decrease cardiovascular disease risk in humans; Examining the intermediate role of adipose tissue in mediating the cardio-protective effects of diet and exercise; Investigating the behavioral factors that influence adherence to dietary restriction strategies.
So this is one lady that ought to understand the effects of what we shovel down our mouths. OK, on to that interview. From Part One, I selected this exchange,
JP: How long does it generally take for people to adapt to this new way of eating?
Dr. Varady: A lot of the subjects were saying that for the first two weeks it was pretty tough to basically change from a 3 meal a day eating pattern to just eating 1 meal a day and then 3 slightly bigger meals the next day. But they said that about after two weeks they totally got used to it and weren’t that hungry on the fast day anymore. They could undergo these really long periods of fasting without really feeling deprived. The other interesting thing that they were telling us was with regard to the feed day. The people didn’t binge. They only ate about 100% to 110% of their calorie needs.
Then from the second part of the interview, JP underlines an important point, “The truth of the matter is that research into ADF is still in its infancy and Dr. Varady is the first person to admit it. ” I then went on to select this exchange between JP and Dr. Varady,
JP: It seems as though ADF provides a very broad array of health benefits. Do you have a theory about why this is possible?
Dr. Varady: In the human data the main thing you see is weight loss. Even if it’s done in normal weight people. The minute you start losing weight you all of a sudden see an improvement in the majority of these factors. A lot of the effects of alternate day fasting are mediated through weight loss. Losing weight is so tightly correlated with your blood pressure, your cholesterol levels and heart rate, etc.
Fasting May Reduce Age-Related Disease Risk Factors
So this is not something of trivial interest, it’s serious research that could have a remarkable effect on the huge problems of obesity and poor diet that affect millions. Do yourself a favour and read the interview now. Part One and Part Two.
Finally, in that post on the 16th, I owned up to having got my weight down to 161.6 lbs (73.30 kgs). Now here we are having completed my third week of 5:2 fasting and last Saturday morning my weight was 159.0 lbs (72.12 kgs). The routine is very comfortable and as Dr. Varady mentioned, there is no sense of wanting to binge after the two days of fasting.
OK, a change to the theme of the last few days, to a topic that must cross the minds of practically every single human being at some point; what is our lifespan going to be? Who doesn’t want to live a long and healthy life, and I don’t wish to be insensitive to those who labour under mental and physical troubles, of course.
So a recent couple of fascinating stories have given an insight into just how to live that longer and healthier life.
The first one is easy – be a woman!
Actress Michelle Ryan as the Bionic Woman was destined to live even longer!
OK, a bit of an issue if you are a man like me but did you realise, because I didn’t, that being the female of many species offers a significant advantage. This came from a BBC item published on the 2nd August, from which I quote,
Scientists believe they have discovered a clue to why women tend to live longer than men – by studying fruit flies.
Writing in Current Biology, they focus on mutations in mitochondrial DNA – the power source of cells.
Mitochondria are inherited only from mothers, never from fathers, so there is no way to weed out mutations that damage a male’s prospects.
Then came an extraordinary fact [my italics below],
By the age of 85, there are approximately six women for every four men in the UK, and by 100 the ratio is more than two to one.
And females outlive males in many other species.
If you are of the scientific bent and/or a woman! you can read a fuller account of the research findings on the Science Daily website. As well as that link you can also read the Monash University press release on those research findings.
As a fella’ I think I’m moving on!
The second one is almost as easy – Fasting
Again, this news came from the BBC website, the news about the power of fasting. In an article promoting the showing of a BBC Horizon programme, Michael Mosley wrote this,
Scientists are uncovering evidence that short periods of fasting, if properly controlled, could achieve a number of health benefits, as well as potentially helping the overweight, as Michael Mosley discovered.
I’d always thought of fasting as something unpleasant, with no obvious long term benefits. So when I was asked to make a documentary that would involve me going without food, I was not keen as I was sure I would not enjoy it.
But the Horizon editor assured me there was great new science and that I might see some dramatic improvements to my body. So, of course, I said, “yes”.
I am not strong-willed enough to diet over the long term, but I am extremely interested in the reasons why eating less might lead to increased life span, particularly as scientists think it may be possible to get the benefits without the pain.
For obvious reasons I can’t republish the full BBC article but I encourage you to read it here. And stay with me for some more research links that are most interesting.
But I will just include this part from the BBC item,
The IGF-1 hormone (insulin-like growth factor) is one of the drivers which keep our bodies in go-go mode, with cells driven to reproduce. This is fine when you are growing, but not so good later in life.
There is now evidence suggesting that IGF-1 levels can be lowered by what you eat. Studies on calorie restrictors suggest that eating less helps, but it is not enough.
As well as cutting calories you have to cut your protein intake. Not entirely – that would be a very bad idea. It’s about sticking to recommended guidelines, something most of us fail to do.
The reason seems to be that when our bodies no longer have access to food they switch from “growth mode” to “repair mode”.
As levels of the IGF-1 hormone drop, a number of repair genes appear to get switched on according to ongoing research by Professor Valter Longo of the University of Southern California.
Intermittent fasting
One area of current research into diet is Alternate Day fasting (ADF), involving eating what you want one day, then a very restricted diet (fewer than 600 calories) the next, and most surprisingly, it does not seem to matter that much what you eat on non-fast days.
Dr Krista Varady of the University of Illinois at Chicago carried out an eight-week trial comparing two groups of overweight patients on ADF.
“If you were sticking to your fast days, then in terms of cardiovascular disease risk, it didn’t seem to matter if you were eating a high-fat or low-fat diet on your feed (non-fast) days,” she said.
Michael Mosley explains how he couldn’t manage Alternate Day Fasting and found it was just too impractical.
Instead I did an easier version, the so-called 5:2 diet. As the name implies you eat normally 5 days a week, then two days a week you eat 500 calories if you are a woman, or 600 calories, if you are a man.
The BBC Horizon programme was screened on the 6th August but is available on the BBC iPlayer for UK viewers. Here’s how it was promoted on the BBC website,
Michael Mosley has set himself a truly ambitious goal: he wants to live longer, stay younger and lose weight in the bargain. And he wants to make as few changes to his life as possible along the way. He discovers the powerful new science behind the ancient idea of fasting, and he thinks he’s found a way of doing it that still allows him to enjoy his food. Michael tests out the science of fasting on himself – with life-changing results.
This programme clip will also attract your attention, trust me!
and if you would prefer a more inspiring antidote then here’s another clip from the programme,
Tomorrow, I’m going to link to the scientists behind these new findings because this is very significant research that could revolutionize the future health for millions.
Finally, I’m here to tell you that Jean and I have ‘signed up’ to the 5:2 pattern and had our fast days last Thursday and Friday. They were much easier than I expected and, frankly, will be fun to maintain. Leave a comment if you would like details of the food and calorific values of what Jean served those two days.
Learning from Dogs 