The FastDay Forum

By coincidence I started the 5:2 at the beginning of January the day after I had some routine fasting blood tests. The GP wants these repeated next week (my triglycerides were high). I will be interested to see if these have improved along with my 8lb weight loss. Has anyone else had the chance to monitor any improvement to blood markers?

[carorees]

Hi Trevmun, welcome to the forum!

Yes, there have been some members with good improvements in blood chemistry. They have reported on them in the Progress Reports board.

Unfortunately they didnt want to repeat fasting bloods but did want to repeat liver function which was abnormal. This latest test, a month after the first test and a month into 5:2 was normal. Obviously cant say if its down to the diet but it may have helped.

Thats very encouraging.

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Its a shame more people (that can) don't post results, although I can understand someone not wanting to put such personal info on the internet.

I wonder if it's something that could be added to the progress tracker to allow the data to be shown anonymously. And if it was would enough people use it to make it worth the effort?

Here are some old blood results of mine from last october. Prior to the test I’d been 5:2ing for 8 weeks, for the first 6 weeks was doing 600kc on fast days split over dinner and b’fast, and for the last 2 weeks was doing 24hr fasts on my fast days (b’fast to b’fast). In conjunction with the IF I also do a good level of exercise swimming 3x pw and cycling 60miles or so pw including 15mile rides on fasting days or a swim between 1-1.5km including sprint work and distance. It’s also worth noting that I’m male in my early 40s.
On the morning of the blood test I had fasted for about 26hrs and in the fasting period had also done a 15 mile bike ride (steady state). The only test results I could compare with were from 3 yrs ago when I wasn’t doing IF but my weekly exercise was of a similar level. Normal ranges are in brackets.

Triglycerides - pre IF 1.09mmol/L, after IF 0.9mmol//L (<2.24mmol/L)
Cholesterol - pre IF 5.0mmol/L, after IF 5.1mmol/L (<5.15mmol/L)
HDL – pre IF 1.62mmol/L, after IF 1.7mmol (>0.89mmol/L)
LDL- pre IF 2.86mmol/L, after IF 3.0mmol (0-3.35mmol/L)
Blood glucose - pre IF 5.1mmol/L, after IF 4.8mmol/L (3.9-6.4mmol/L)
Bilirubin – pre IF 32umol, after IF 77umol (0-22umol/L)

[carorees]

When fasting your blood cholesterol goes up dramatically as there are high amounts of fats circulating to be used as fuel, so your after IF results are not really comparable with the pre IF results. It's best to do just a 12 hour fast before the blood tests so they will be comparable with the standards.

Caroline, am not sure I totally agree with you re testing cholesterol after a 12hr fast. I'm interested to see what is going on in internally after doing what for me is a regular fasting day. Would be great if we could do blood tests every day to get an even fuller picture.
As interesting as the cholesterol results are I'm not concerned as they are still regarded as not dangerously high by those who consider high cholesterol to be bad. I'm now in the camp that high cholesterol isn't all bad. If you take someone who is obese, has high bp and has a sedentary lifestyle then i think high cholesterol readings will help to indicate that the person is on a slippery slope health wise. But, for someone like myself who is pretty active, low bp and not obese I don't think cholesterol readings should be given high attention.
Re the results and your comment I'm also surprised the triglycerides weren't higher?
For anyone interested in reading more I suggest googling cholesterol and taubes.

[carorees]

Ok, its just that the OP was interested in improvements in bloods which needed to be based on the standard used by docs which is after a 12 hour fast. Of course what is happening after a longer fast is interesting but cannot be used in cardiovascular risk prediction.

The free fatty acids go up a lot during fasting, see for example here, but does cholesterol ?

[carorees]

I posted this in the science watch thread that was running before we got our own board to discuss science:

And here is another very interesting paper published last month that looked at the changes occurring in the body after a 24-hour fast.

The study (http://www.ncbi.nlm.nih.gov/pubmed?term ... od%20trial) looked at healthy volunteers who fasted on water only for 24 hours. On another day they ate normally and the values for cholesterol and so on were compared across the two days. The study found that cholesterol levels (all types) had increased significantly by the end of the fast because the liver was mobilising fat from stores to use as food. Also increased were growth hormone levels (which acts to stop muscle being broken down for food and increases the release of fat from stores). Weight decreased. After eating, all levels went back to what was normal for the person except for weight. The authors conclude that "repeated episodes of periodic short-term fasting should be evaluated as a preventive treatment with the potential to reduce metabolic disease risk." which is to say that intermittent fasting might reduce the risk of cardiovascular disease.

Of course, we are doing that experiment for them now!

It occurred to me, however, that if you are going to the doctor's to have your cholesterol checked you should probably not schedule it for the day after a fast as it might give a misleading result!