Prepping for a blood test

lipids
blood
tests
fasting
cholesterol
#1

My doctor is asking me to go off my ketogenic diet for several days before a blood test (lipids), on the assumption that a fatty diet will impact blood test results, even if I’m fasting for the normal time before the test. Questions:

  1. Is that the right assumption?
  2. If so, what might the effect on typical cholesterol readings be? (I know I may need to ask for NMR and other tests depending on results, but what would the expected impact of being on a solid keto diet right up until the pre-test fast, on the more standard tests my doctor is likely to run?)

Context: I’m on keto primarily because my wife and daughter NEED to be for specific health reasons. But I’m losing weight and liking it, and don’t want to mess it up or get incorrect readings. I also have a family history of heart disease, so keto is a concern for my doctor.

Blood Panel Question
(Naomi Brewster) #2

Check out Dave Feldman - cholesterol code - for instructions how the eat three days prior blood test to hack results

#3

Thanks @gnomesb – I am reading it, but I have to admit I’m not fully understanding it, nor am I really trying to “hack” the test… I want to get accurate results.

I guess from reading there… I should assume that if I ate my normal (keto) way… I might very well have higher cholesterol readings on a test after three days. What I don’t understand is… is that OK? Does it more accurately reflect what my body is doing and whether I’m healthy cholesterol-wise? Conversely, if I switch back to a lower fat diet coming up to the test (like my doctor says)… am I getting a more or a less realistic view of what is really going on when I’m eating keto?

(Naomi Brewster) #4

It is pretty complex and I am not across it myself but here’s how I understand it: Dave Feldman is a ‘high responder’ which means that he gets unusually high readings of LDL when he’s on keto and he is trying to get to the bottom of what this means, are these results meaning that he is damaging his heart/clogging of arteries - which is how high cholesterol has been understood for 50 years etc. What he discovered, and part of his ‘hack’ for good cholesterol readings is that a cholesterol test is a reflection of the last three days only and more dietary fat means less LDL in the system - fasting and low fat will skyrocket your readings. His blog ‘The cholesterol code’ is trying to get to the bottom of the mechanisms involved. If you have a family history of heart disease then you will likely find his blog very interesting - he has tried to explain the mechanisms in a way that you can understand. Good luck getting to the bottom of it.

As a side note: Dave feldman’s sister and father are not high responders and have normal readings of cholesterol on a ketogenic diet

(VLC.MD) #5

Do the cholesterol tests next year

#6

If it were me, I wouldn’t change anything before the test. I’d want to know what my numbers are based on my WOE and lifestyle. If they’re fine, then I know what I’m doing isn’t detrimental. If they’re whacked, then I’ve got more investigation to do.

PS: with a history of HD, I’d also get a coronary calcium scan.

(Jack Brien) #7

There are other issues here too. If you haven’t been keto for very long and are still losing weight, that will also bump up your cholesterol. But also, is your cholesterol test even relevant? I feel that my Dr just doesn’t understand the issues and how different tests can give a far more relevant results. For instance,my last test about a year ago, showed high total cholesterol, but a good HDL/trig ratio. This time I asked for a LDL-P test in addition as she wants me to take statins. She refused on the basis that she had never heard of it. She also told me that eating fat raises cholesterol, not sugar. At that point I ceased to care about her view. I did the Feldman thing, hoping it might make her think differently.

#8

And did it make her think differently @Jack_Brien :slight_smile: ?

(Randy) #9

My opinion is just keeping to your plan. Heart disease is caused by inflammation. KETO is a low inflammation diet.
Also, it is apparently our own job to manage our health and diet. Because if you’ve done any amount of research, you probably know more than your doctor about this stuff.

Sad but true.

True science based doctors are heroes, because they go against “common practice” and actually follow the science. They are few and far between at this point.

KCKO.

(Jack Brien) #10

Results are here, but the LDL is still high, so I doubt she will be going keto!
https://www.ketogenicforums.com/t/the-feldman-protocol-thread/7789/39?u=jack_brien

(Siobhan) #11

Blood tests are very fluid (haha) as far as results go, so if you want accurate numbers eat as you normally do, as much food as you normally have, your favorite foods if you want (e.g. the ones you eat most).

Why would you want results that reflect a diet you dont normally eat?
You want to get a window of your typical day so you can see how your body responds inflammation wise, etc

Note that as Dave demonstrates your LDL may go up from pre-keto baseline (but not always) this is just because LDL particles transport fat energy (triglycerides) as their primary job. They also carry cholesterol for “in case of emergency” situations like damaged cell repair.
Thus when relying more on fat energy, your fat transporters (LDL) may go up as a consequence because without energy things dont end well.
I wrote a post on Dave’s site (that now has a part 2 out) that goes over the mechanisms of atherosclerosis and may explain why I’m personally not altogeher concerned with my relatively high cholesterol on keto.

Ivor Cummins also has a video showing the real correlative marker for heart disease, insulin. It’s on youtube.

Hope that helps!

#12

Thanks everyone. My plan now after reviewing all your awesome comments is to go a week on a “weight maintenance” keto diet (not try to lose any weight this week). But still keto. Then get my blood tested. If it’s out of whack, then order better tests. But not freak out :slight_smile: Thanks everyone. Great forum.

(Mike W.) #13

I would wait 90 days after you reach goal or at least stop losing weight, but that’s me. This blood test will just be a “snapshot” and not give you much information about your current health.

(Roberto) #14

well, you can always order more bloodwork yourself and retest to have fun with it and recheck after several days… i think it’s only about $20 for me to order my own…we have several low cost labs…Most states in the usa let us patients order our own

(paul brignac) #15

KCKO, Totally agree. My GP gave me a lukewarm response when I told him Had started IF. Fast forward 5 months and I have started LcHf diet and (2) 40 hr fast a week. I’ve lost 40#,am no longer obese with avg BG reading of 6.1, down from 6.9. I have 25# more to lose and want BG down in the low 5’s. Due to my GP’s attitude, should I tell him that I quit the glimeperide a month ago, when I go to check-up on Feb 20? or IYHO would it be better not to tell him at all? He takes good care of our family, but doesnt seem to be open to different ideas on diet, T2D. Thx Aim

(KCKO, KCFO) #16

Paul, I just tell my dr. I have gone on a lowe carbs, healthy fats diet. She said, " so basically a low carb mediterranean diet? I said yes. Because I’ve been in several Mediterranean countries and they all had bacon, pork, steaks, etc. Not just pasta and bread with sauces. I use a lot of olive and avocado oils.

KETO has become sort of a loaded term. Just phrase it differently and you should be fine. She told me to keep doing what I was doing because it was really working for me. Gotta admit I did not tell her about all the fasting I did to lose the last 15-20 stubborn lbs. I’m not on any meds, but if I had been and stopped them I would have let her know about it straight up.

(Brian Chandler) #17

My first NMR wasn’t able to get me all the readings from VLCHF at the time. Some readings were way too high from the HF. I adjusted my fat ratios over the next few months, (temp added in statin so sadly can’t rule that out for you), and read about Dave’s stuff. With that info, I decided to adjust by trying to eat most accurate to my norm around 3 days before. I also fasted the full 12 hours before the test. This recent NMR looked really good and got me more usable and sensible data, so I’m inclined to say stay on the diet for the reading, but be sure you are tracking around the 3 day mark in something like Cronometer to provide some form of control (i.o.w. don’t intuitively eat.) Most doctors are not well versed in VLCHF if that’s what you are doing. If keto, you really do need to do the NMR instead of the older “normal” cholesterol test to get a pulse on small dense particle LDL (in my opine.) Another gotcha is that it seems to take a long time for the changes/results from the keto to stabilize (about the 1 yr to 1.5 yr mark for me.) Before then, my body seemed to go through at least 3 adjustment periods where I had to tweak diet, etc. What did well starting out did not do well later. Finally, while there, have them get a pulse on your Vitamin D. Deficiency there can come with the diet. You can easily correct it with a small amount of supplementation. Above is just from my experience. I am not a doctor.

(Brian Chandler) #18

Just realized how old the post was. One of these days I should learn to check dates. lol

#19

Better late than never :slight_smile:

(Empress of the Unexpected) #20

I do that all the time - and sometimes generate new interest in the topic.