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Dehydration Associated with LCHF

Listlad

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3,971
Type of diabetes
Prediabetes
Treatment type
Diet only
I have just started to adjust my diet by lowering the amount of carbs and increasing the fat. Not completely and utterly but in a transitional way. Coincidentally I have been waking earlier, feel particularly dehydrated, with red eyes and this morning constipation.

Is this normal for a low carb high fat approach?

Thanks for input into this.
 
I low carb bot am not a lover of fatty foods so am not particularly "high fat" but I haven't found that.

However I do eat a lot more veg than I used to (they have a high water content) and as I have never drunk much I try to remember to drink more.The extra veg also helps with constipation.

Have you changed anything else in your diet, exercise etc.
 
Carbohydrates help the body to retain water, and when you stop eating them you will lose more fluids. It is this loss that causes the rapid loss of excess pounds! Lovely though this is, you can become dehydrated until your body adjusts. It is important to get into the habit of drinking water throughout the day. I found that salty drinks lke Bovril helped, and there are many recpes for bone broth on line. These help to replace the minerals that you are losing. Contrary to current advice,you may need to add a bit more salt to your diet, until you get used to your new way of eating. I was plagued with headaches for the first couple of weeks, when I reduced carbs, but everything settled down and I take less salt again now.
 

If you are in metabolic ketosis then yes this can be a factor. My understanding is that it’s brought about predominantly by the kidneys trying to excrete sodium in urine. Likely you’ll be urinating more even if it’s only a small amount. Most people report that this goes away if they increase salt intake and drink plenty of water.
 
Not unusual. Carbs hold water. Without them it’s harder to hold water. I can certainly tell if my fluid intake isn’t as high as it could and should be. Easily solved by drinking more or eating fluid filled foods. It soon becomes the new normal
 
Not really. Just a halfway house shift over to LCHF. I have kept the same level of liquid intake too. So that might need to change.
 
Hi @Listlad, there is a condition labelled 'keto 'flu" where persons starting on the LCHF diet feel unwell. The pundits do think this is related to shifts of salts and fluids in the body and various remedies by low carbers are suggested like increased fluids, added salt to food and some suggest Magnesium tablets. The latter however might depend on what one's kidney function is like first?
Nausea was my most most troublesome symptom (? due to increase in ketones) with lethargy, irritability and lack of motivation close seconds.
As a T1D on an insulin pump, I only started in earnest with low carb intake (40 to 45 g carb per day including allowance of 50% for protein, 6 weeks ago.
I feel that I was through the worst of the keto 'flu and coming out of the "tunnel" after the second week but see below *.
I assume my body has now fully adapted (fingers crossed).
*Heatwave conditions in Australia through part of this time also knocked me about and I cannot be sure how much of my feeling unwell was down to the keto 'flu and how much to ambient temperatures.
I would certainly caution new starters to avoid summer time in Australia, that may not of course apply elsewhere.
Also see https://www.dietdoctor.com/lowcarb/com/keto/flu-side-effects
 
Thanks, I thought you guys and girls would know. And I did feel better after having a glass of sugar free orange squash.

Point noted about the salts. So I will have to look at that.
 
That’s it, so often their can be other root causes.
 
And....I suppose if one drops stuff like rice or pasta for example then they being full of water, will not be in the daily water intake tally.
 
Listlad said:
And....I suppose if one drops stuff like rice or pasta for example then they being full of water, will not be in the daily water intake tally.
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Water in vegetables help with fluid and fibre, and psyllium husk can give the extra fibre if need be for constipation I find without having to resort to prunes and the like. The vegetables can also provide the vitamin C which you otherwise miss out on when you stop fruit and the like.
 
I just earlier had a banana (potassium) but I gather it isn’t the best fruit to choose. Having drunk copious quantities of tea, cordial and water all day I feel less rough than I did this morning.


Have just read the DietDoc stuff. Thanks.
 
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Listlad said:
I just earlier had a banana (potassium) but I gather it isn’t the best fruit to choose. Having drunk copious quantities of tea, cordial and water all day I feel less rough than I did this morning.
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Mmm yes better sources of potassium to be had without an entire days carbs (and more for some) being used. I think lots use pink Himalayan salt. Me I just use sea salt. Not sure which ones that has but it seems to do the job and a blood test 3 months after I went keto showed potassium and magnesium ok so I’m getting it somewhere.

Great that the extra fluids are helping.
 

I try and steer away from salt from the blood pressure angle. I have high blood pressure too, unfortunately.

I did have a bacon butty this morning so there will be salt in that, I suspect.

And a slice of cheese. That has salt in.
 
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Get some rehydration salts from the chemist.

Don't need a whole sachet but I put some in my water bottle I drink from through the day. Sorted me right out.

Don't need it now.
 
Listlad said:
I try and steer away from salt from the blood pressure angle. I have high blood pressure too, unfortunately.

I did have a bacon butty this morning so there will be salt in that, I suspect.

And a slice of cheese. That has salt in.
Click to expand...

I don’t use much salt but I use Pink Himalayan salt when I do. I had, high blood pressure and was on two meds when I got my type 2 diagnosis. My BP has normalised and I was able dropped one of the meds. For the constipation I got with low carbing I just upped my intake of seeds
 
Where do you get Himalayan salt? I shall google it.

I shall try the seeds though @Rachox . I love prunes but I bet they are hi carb.



I just googled Himalayan salt and it is sodium chloride to the tune of 98% with the rest being auxiliary minerals. It will have been generated by evaporation from the seas back in the day, millions of years ago. My guess is that it has similar properties of regular table salt, but I am all ears on responses on that one.

Once upon a time the Himalayas were under water.
 
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