Fasting blood work
WholeFoods4Lyfe
Posts: 1,518 Member
So, I went for my annual physical this morning and my doctor ordered some routine blood work. I'm supposed to be fasting for this blood work. I was going to go this afternoon and just get it over with, but I'm wondering if there is any difference between first thing in the morning or not. I'll be at about 19 hours if I go this afternoon. Thoughts?
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Plenty. Normal "fasting" for blood work is no eating or drinking after 6 PM the night before if your blood work appointment is the next morning.0
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Plenty. Normal "fasting" for blood work is no eating or drinking after 6 PM the night before if your blood work appointment is the next morning.
So what are the differences? I leave my house at 6am to go to work and don't get home until 5pm, The lab is only open 6am-5pm, so I don't know when I'll be able to go. I'm home today for my appointment.
Depending on the differences, I may say eff it and just go. Will it have a negative impact on things like Blood Glucose or Cholesterol?
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So, I called my doctor (not sure why I didn't just do that in the first place LOL) and they said that I am fine.
I am still curious though for your thoughts on why there would be plenty of issues getting blood work done on a 19 hour fast.0 -
That’s how I did my recent blood work.
I had fasted from around 9 pm the previous night and my appointment wasn’t until 3:30pm.
My doctor just asked me “are you sure you haven’t eaten or drank anything?”
He couldn’t believe I could go so long with only black coffee that morning. He was even more surprised when I said I fast til around 2/2:30 every day anyway just based on hunger.
My numbers were great!4 -
Here is some food for thought -
http://cholesterolcode.com/the-fasting-disaster/
This shows how much cholesterol can change with a 3 day fast. Granted, you are only talking about an extra 5-6 hours than normal, but still kind of interesting.
If you are not familiar with Dave Feldman, he has a pretty interesting theory around all this regarding how your blood will try to get to homeostasis in regard to how much total energy there is in the blood which comes in 3 primary forms - glucose, ketones and fatty acids (triglycerides).
Unless you are T1 diabetic, there is a 99.9% chance your body has an upper limit for ketones. As glucose goes down, ketones will generally rise and vice versa. However, sometimes, such as during fasting, your ketones may not be able to go up enough to make up for the lower BG, in which case the additional energy in your blood will be in the form of triglycerides which will also mean LDL will be higher as that is how they are transported from the liver.
Again, I really don't think the few extra hours you are talking about is going to have a significant effect, but this is just so you have second thoughts about getting blood work done after a more extended fast.3 -
Genius! I never thought about doing FBG later in the day. For me, that would be the difference between a 5.6 and much lower, like a 4.8... Especially if I get to eat since that usually drives down my BG within 30 minutes. LOL
The morning tests would only need to be in the morning if it is measuring something specific to that time of the day like cortisol which is usually highest early in the morning. Fir a fasting test? It really should not name any difference when you do it.
I wonder if it would vary more for someone who is more glucose dependent compared to someone fat adapted?
And I love Dave Feldman's work.1 -
UPDATE:
Did my blood work and just got my numbers back. I was concerned about the BG and Cholesterol numbers, not sure why, I just think I remember reading somewhere that they could be skewed after a longer fast.
Blood Glucose: 66
Total Cholesterol: 178
Ratio: 3.78
HDL: 47
Trigs: 89
LDL: 113
I was really surprised by the BG number. I've always tested 90 and above, well above previously actually when I was diagnosed as pre-diabetic, so that 66 was a welcome surprise.
I'm very happy with my Cholesterol numbers as well. My LDL is considered to be high, but I expected that as I am actively losing weight. And, I'm still under 200 which I know is what my doctor looks at really. My ratio is great.
All of my other numbers are great as well including my Sodium, Potassium, and Magnesium which were a concern because I follow a Keto diet.
My Vitamin D was just a touch outside of normal on the low side which wasn't a huge surprise either. Vitamin D deficiency is common in my family, my Mom has Osteopenia, but my level was 29.7. According to the lab "normal" is 30, but my prior research showed 40 as being normal/average, so even though I spend a good bit of time outside in spite of my office job, I'm going to start supplementing again. My Calcium level is fine, so I'm happy about that.
Anyway, that's my update. Thanks for reading
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Such great numbers! Out of curiosity, how do you have your macros set? What's a "normal" day of eating like for you? (I'm reading a Johnny Bowden book on low carb eating, and a Chris Kressler book, and geeking out this week, in between semesters.)WholeFoods4Lyfe wrote: »UPDATE:
Did my blood work and just got my numbers back. I was concerned about the BG and Cholesterol numbers, not sure why, I just think I remember reading somewhere that they could be skewed after a longer fast.
Blood Glucose: 66
Total Cholesterol: 178
Ratio: 3.78
HDL: 47
Trigs: 89
LDL: 113
I was really surprised by the BG number. I've always tested 90 and above, well above previously actually when I was diagnosed as pre-diabetic, so that 66 was a welcome surprise.
I'm very happy with my Cholesterol numbers as well. My LDL is considered to be high, but I expected that as I am actively losing weight. And, I'm still under 200 which I know is what my doctor looks at really. My ratio is great.
All of my other numbers are great as well including my Sodium, Potassium, and Magnesium which were a concern because I follow a Keto diet.
My Vitamin D was just a touch outside of normal on the low side which wasn't a huge surprise either. Vitamin D deficiency is common in my family, my Mom has Osteopenia, but my level was 29.7. According to the lab "normal" is 30, but my prior research showed 40 as being normal/average, so even though I spend a good bit of time outside in spite of my office job, I'm going to start supplementing again. My Calcium level is fine, so I'm happy about that.
Anyway, that's my update. Thanks for reading
Regardless, congrats!
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Sabine_Stroehm wrote: »
Such great numbers! Out of curiosity, how do you have your macros set? What's a "normal" day of eating like for you? (I'm reading a Johnny Bowden book on low carb eating, and a Chris Kressler book, and geeking out this week, in between semesters.)WholeFoods4Lyfe wrote: »UPDATE:
Did my blood work and just got my numbers back. I was concerned about the BG and Cholesterol numbers, not sure why, I just think I remember reading somewhere that they could be skewed after a longer fast.
Blood Glucose: 66
Total Cholesterol: 178
Ratio: 3.78
HDL: 47
Trigs: 89
LDL: 113
I was really surprised by the BG number. I've always tested 90 and above, well above previously actually when I was diagnosed as pre-diabetic, so that 66 was a welcome surprise.
I'm very happy with my Cholesterol numbers as well. My LDL is considered to be high, but I expected that as I am actively losing weight. And, I'm still under 200 which I know is what my doctor looks at really. My ratio is great.
All of my other numbers are great as well including my Sodium, Potassium, and Magnesium which were a concern because I follow a Keto diet.
My Vitamin D was just a touch outside of normal on the low side which wasn't a huge surprise either. Vitamin D deficiency is common in my family, my Mom has Osteopenia, but my level was 29.7. According to the lab "normal" is 30, but my prior research showed 40 as being normal/average, so even though I spend a good bit of time outside in spite of my office job, I'm going to start supplementing again. My Calcium level is fine, so I'm happy about that.
Anyway, that's my update. Thanks for reading
Regardless, congrats!
I'd say that my GOALS are 10% carbs / 60% fats / 30% proteins. That said, I don't really pre-plan my meals or anything and this is where my numbers tend to fall most days by practicing intuitive eating. It helps that I don't eat gluten or dairy, so really by just focusing on veggies as my carb source helps my numbers to fall in line.
Most days I practice IF, so I don't eat breakfast. Today is actually a longer fast and I'll only eat dinner. On a normal day where I'm doing 19:5 IF, I'll have lunch around 1pm and it's usually a salad with lots of green veggies, healthy protein like chicken or salmon, and I almost exclusively use my own Balsamic Vinaigrette. For dinner around 6pm, I tend to base my plate around my meat and do steaks like NY Strip or Ribeye, chicken legs/thighs, dark meat pork, fish like Salmon or Blue Fish. Then I usually just do a side veggie like zucchini fried in bacon fat, or asparagus wrapped in bacon, spinach and mushrooms sauteed in evoo, stuff like that. Another quick dinner idea which is a great summer salad and good if you like seafood: 1 avocado chopped, 1 small tomato chopped, 1T chopped onions, 1T lime juice, 1T lemon juice, small handful cilantro, salt and pepper to taste. Then I'll add either 6oz of shrimp chopped or 6oz sushi grade raw salmon, chopped. Toss it all together and enjoy. It's like a Ceviche, super yummy and filling. I probably eat that at least one night per week. I will occasionally snack on nuts or black olives. HTH!
Also, my diary is open, so feel free to take a look. I didn't really track this weekend because we had a lot of functions to go to, so I just sat by the low carb snacks like deviled eggs and shrimp but didn't track anything.1 -
66! Very nice.
Fasting can raise triglycerides and cholesterol a bit. Who knows, it might have been even better with minimal fasting.
looks good. Congrats! 0 -
WholeFoods4Lyfe wrote: »Sabine_Stroehm wrote: »
Such great numbers! Out of curiosity, how do you have your macros set? What's a "normal" day of eating like for you? (I'm reading a Johnny Bowden book on low carb eating, and a Chris Kressler book, and geeking out this week, in between semesters.)WholeFoods4Lyfe wrote: »UPDATE:
Did my blood work and just got my numbers back. I was concerned about the BG and Cholesterol numbers, not sure why, I just think I remember reading somewhere that they could be skewed after a longer fast.
Blood Glucose: 66
Total Cholesterol: 178
Ratio: 3.78
HDL: 47
Trigs: 89
LDL: 113
I was really surprised by the BG number. I've always tested 90 and above, well above previously actually when I was diagnosed as pre-diabetic, so that 66 was a welcome surprise.
I'm very happy with my Cholesterol numbers as well. My LDL is considered to be high, but I expected that as I am actively losing weight. And, I'm still under 200 which I know is what my doctor looks at really. My ratio is great.
All of my other numbers are great as well including my Sodium, Potassium, and Magnesium which were a concern because I follow a Keto diet.
My Vitamin D was just a touch outside of normal on the low side which wasn't a huge surprise either. Vitamin D deficiency is common in my family, my Mom has Osteopenia, but my level was 29.7. According to the lab "normal" is 30, but my prior research showed 40 as being normal/average, so even though I spend a good bit of time outside in spite of my office job, I'm going to start supplementing again. My Calcium level is fine, so I'm happy about that.
Anyway, that's my update. Thanks for reading
Regardless, congrats!
I'd say that my GOALS are 10% carbs / 60% fats / 30% proteins. That said, I don't really pre-plan my meals or anything and this is where my numbers tend to fall most days by practicing intuitive eating. It helps that I don't eat gluten or dairy, so really by just focusing on veggies as my carb source helps my numbers to fall in line.
Most days I practice IF, so I don't eat breakfast. Today is actually a longer fast and I'll only eat dinner. On a normal day where I'm doing 19:5 IF, I'll have lunch around 1pm and it's usually a salad with lots of green veggies, healthy protein like chicken or salmon, and I almost exclusively use my own Balsamic Vinaigrette. For dinner around 6pm, I tend to base my plate around my meat and do steaks like NY Strip or Ribeye, chicken legs/thighs, dark meat pork, fish like Salmon or Blue Fish. Then I usually just do a side veggie like zucchini fried in bacon fat, or asparagus wrapped in bacon, spinach and mushrooms sauteed in evoo, stuff like that. Another quick dinner idea which is a great summer salad and good if you like seafood: 1 avocado chopped, 1 small tomato chopped, 1T chopped onions, 1T lime juice, 1T lemon juice, small handful cilantro, salt and pepper to taste. Then I'll add either 6oz of shrimp chopped or 6oz sushi grade raw salmon, chopped. Toss it all together and enjoy. It's like a Ceviche, super yummy and filling. I probably eat that at least one night per week. I will occasionally snack on nuts or black olives. HTH!
Also, my diary is open, so feel free to take a look. I didn't really track this weekend because we had a lot of functions to go to, so I just sat by the low carb snacks like deviled eggs and shrimp but didn't track anything.
Thanks for this!0 -
Today the doctor went over 5 pages of lab results from my fasting blood work last week.
She was pleased with my annual results and general health since starting Keto Oct 2014.
Well the Vit D level of >155 ng was well above the average of test results she said but agreed there is no hard science as to the idea levels. This is the same results as a year ago. I am taking 50K units daily with both MK4 and MK7 of K2. She said since my Magnesium and Calcium were normal as well as kidney function testing she saw no reason to change what I have been doing for two years now. I was negative for urine ketones which shows why urine test strips can be worthless for one living on ketones long term.
Dressed weight was 204 the two prior years and 200 today. As you know I track nothing but weigh twice most morning but do not record it any longer. Being to eat all that I want when I want it and maintain never happen before I started keto. Pre keto (Aug 2014) she said I weight 252 pounds.
Blood Glucose: 92 (pre keto it ran 105-115 fasting)
A1C: 5.1
Total Cholesterol: 306 down from 341 last year and 404 in 2015(9 months after started KETO).
HDL: 60
Trigs: 88
LDL: 228
I get the sense I am a rare bird in the clinic to be Rx med free and no health concerns to follow at age 67.
In 2014 they were trying to get me to start Enbrel injections for pain management because of my 7-8 pain levels which stay under a level of one 95% of the time. It all started out as a hunch if I would cut out food sources that contained added sugar and or any form of any grain that I could manage my pain without Enbrel injections. Today I spent the rest of the day working on restoring a 70 year old tractor like the one I played on when I was three years old and started driving when I was 5.
Life is great on all levels. The doctor actually stated she did not see any upcoming health concerns based on my current exam and labs so I am gunning for 110+ walking and talking the entire way. I wish more could see Keto/LCHF was about living and not just weight loss.10 -
GaleHawkins wrote: »Today the doctor went over 5 pages of lab results from my fasting blood work last week.
She was pleased with my annual results and general health since starting Keto Oct 2014.
Well the Vit D level of >155 ng was well above the average of test results she said but agreed there is no hard science as to the idea levels. This is the same results as a year ago. I am taking 50K units daily with both MK4 and MK7 of K2. She said since my Magnesium and Calcium were normal as well as kidney function testing she saw no reason to change what I have been doing for two years now. I was negative for urine ketones which shows why urine test strips can be worthless for one living on ketones long term.
Dressed weight was 204 the two prior years and 200 today. As you know I track nothing but weigh twice most morning but do not record it any longer. Being to eat all that I want when I want it and maintain never happen before I started keto. Pre keto (Aug 2014) she said I weight 252 pounds.
Blood Glucose: 92 (pre keto it ran 105-115 fasting)
A1C: 5.1
Total Cholesterol: 306 down from 341 last year and 404 in 2015(9 months after started KETO).
HDL: 60
Trigs: 88
LDL: 228
I get the sense I am a rare bird in the clinic to be Rx med free and no health concerns to follow at age 67.
In 2014 they were trying to get me to start Enbrel injections for pain management because of my 7-8 pain levels which stay under a level of one 95% of the time. It all started out as a hunch if I would cut out food sources that contained added sugar and or any form of any grain that I could manage my pain without Enbrel injections. Today I spent the rest of the day working on restoring a 70 year old tractor like the one I played on when I was three years old and started driving when I was 5.
Life is great on all levels. The doctor actually stated she did not see any upcoming health concerns based on my current exam and labs so I am gunning for 110+ walking and talking the entire way. I wish more could see Keto/LCHF was about living and not just weight loss.
I love your updates Gale! I’m so happy you found your path to your best possible health.2 -
well I am worried , sept 12 is my doctor's appt and she always does A1c (3 months) and my morning BS have been awful , I am fasting 12 to 16 hours and only eating low carb and sometimes only eating 2 meals a day , but my morning BS's are anywhere from 110 to 140 This is not good , I have been doing this for months and last A1c was 6.1 and trust me that was good , the one before that was 9.1 , so I have been reading about this Dawn affect , BUT I don't know how to fix it , I ate more carbs at dinner last night and woke up to a 125 bs , still too high . what i read as well is NOT to start taking the lantus again at night because that would drop my sugar even lower at night and make me wake up even higher BS . So what to do ? MY doc is not a very talky talk kind of person , she basically says this is it , now do it and she walks out of the room doesn't give me time to talk about all this , that is why I am doing this all on my own. I just really hate I had my BS under control and waking up to almost perfect BS (for me) and now I am all over the place .
Doc always has me do a fasting Blood Sugar test in the morning . IF it was later in the day she will not do an A1c . she doesn't believe me if I say I haven't eaten . but that is because I am still fat , they never believe you when your fat !4 -
Hey, @tammyfranks2, just thinking out loud.... what if you woke earlier on the day you have your tests (but don't tell them that) - would your fasting BS be down a bit by the time you go to the lab and maybe also get the A1c??? I don't have any experience with this kind of thing, but maybe????2
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Maybe take a leisurely 15 minute walk about 2 hours before the test.2
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I've never had known issue with anything diabetes related but it seems one would need/want to find more of a long term fix versus doing something for 1 day to skew the test results.
I must be missing something....1 -
canadjineh wrote: »Hey, @tammyfranks2, just thinking out loud.... what if you woke earlier on the day you have your tests (but don't tell them that) - would your fasting BS be down a bit by the time you go to the lab and maybe also get the A1c??? I don't have any experience with this kind of thing, but maybe????
oh I get what you are saying and yes I can ....and yes if I am up for awhile and don't eat , it does drop some .0 -
I've never had known issue with anything diabetes related but it seems one would need/want to find more of a long term fix versus doing something for 1 day to skew the test results.
I must be missing something....
A1c go back 3 months so no just one day wouldn't make a difference , but at lease that morning it would be lower .and doc may not be so mean LOL1 -
Dawn Effect is just one of those things. My morning numbers are higher than I would like too. Every now and then mine will be ok, but I can't seem to find anything to predict it.
FWIW, my last fasting number at the doctor's office was 95. I had checked four hours or so before the appointment when I woke up. The average for the morning numbers in the previous week was probably 110.3 -
I'm not diabetic, but my understanding is that the Dawn Phenomenon should not impact A1C levels since it generally only boots BSG for a few hours.
There are some strategies for mitigating it here, not sure if these are things you have already tried:
https://blog.virtahealth.com/dawn-phenomenon/1 -
GaleHawkins wrote: »Today the doctor went over 5 pages of lab results from my fasting blood work last week.
She was pleased with my annual results and general health since starting Keto Oct 2014.
Well the Vit D level of >155 ng was well above the average of test results she said but agreed there is no hard science as to the idea levels. This is the same results as a year ago. I am taking 50K units daily with both MK4 and MK7 of K2. She said since my Magnesium and Calcium were normal as well as kidney function testing she saw no reason to change what I have been doing for two years now. I was negative for urine ketones which shows why urine test strips can be worthless for one living on ketones long term.
Dressed weight was 204 the two prior years and 200 today. As you know I track nothing but weigh twice most morning but do not record it any longer. Being to eat all that I want when I want it and maintain never happen before I started keto. Pre keto (Aug 2014) she said I weight 252 pounds.
Blood Glucose: 92 (pre keto it ran 105-115 fasting)
A1C: 5.1
Total Cholesterol: 306 down from 341 last year and 404 in 2015(9 months after started KETO).
HDL: 60
Trigs: 88
LDL: 228
I get the sense I am a rare bird in the clinic to be Rx med free and no health concerns to follow at age 67.
In 2014 they were trying to get me to start Enbrel injections for pain management because of my 7-8 pain levels which stay under a level of one 95% of the time. It all started out as a hunch if I would cut out food sources that contained added sugar and or any form of any grain that I could manage my pain without Enbrel injections. Today I spent the rest of the day working on restoring a 70 year old tractor like the one I played on when I was three years old and started driving when I was 5.
Life is great on all levels. The doctor actually stated she did not see any upcoming health concerns based on my current exam and labs so I am gunning for 110+ walking and talking the entire way. I wish more could see Keto/LCHF was about living and not just weight loss.
Such a great report. You have really taken control of your health issues.
Always great to catch up with your progress and new experiments when you do them.
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tammyfranks2 wrote: »well I am worried , sept 12 is my doctor's appt and she always does A1c (3 months) and my morning BS have been awful , I am fasting 12 to 16 hours and only eating low carb and sometimes only eating 2 meals a day , but my morning BS's are anywhere from 110 to 140 This is not good , I have been doing this for months and last A1c was 6.1 and trust me that was good , the one before that was 9.1 , so I have been reading about this Dawn affect , BUT I don't know how to fix it , I ate more carbs at dinner last night and woke up to a 125 bs , still too high . what i read as well is NOT to start taking the lantus again at night because that would drop my sugar even lower at night and make me wake up even higher BS . So what to do ? MY doc is not a very talky talk kind of person , she basically says this is it , now do it and she walks out of the room doesn't give me time to talk about all this , that is why I am doing this all on my own. I just really hate I had my BS under control and waking up to almost perfect BS (for me) and now I am all over the place .
Doc always has me do a fasting Blood Sugar test in the morning . IF it was later in the day she will not do an A1c . she doesn't believe me if I say I haven't eaten . but that is because I am still fat , they never believe you when your fat !
Sounds like you need a new doctor. A1c is for the past 3 months, what time of day the draw is taken is meaningless. Lots of people with non diabetic A1c levels can have an early morning fasting BS of over 100.1
