What type of doctor would know about low potassium & low phosphorous issues?

[Neunistiva]

do you suffer from premenstrual related mood disorder?

I do have PMS but

1. All women in my family have it much worse than I do, and they are perfectly healthy

2. I think it's just one of the normal symptoms of ME/CFS because my PMS worsened as soon as I got ME/CFS almost a decade ago, and fT3 was normal back then

What did you have in mind?

 

[pattismith]

I do have PMS but

1. All women in my family have it much worse than I do, and they are perfectly healthy

2. I think it's just one of the normal symptoms of ME/CFS because my PMS worsened as soon as I got ME/CFS almost a decade ago, and fT3 was normal back then

What did you have in mind?

this is an abstract from a study I read, where premenstrual mood disorder can be secondary to some trauma in some cases, which is similar to PTSD, and it says:

"While the HPT-axis is not responsive to minor stress, it is responsive to severe traumatic stress (4). A number of studies in men with combat related post-traumatic stress disorder (PTSD) have documented elevated T3 concentrations, together with an increase in the T3/T4 ratio, an index of increased peripheral conversion of T4 to T3 (5–7). The clinical relevance of this HPT-axis pattern in combat-related PTSD is suggested by the correlation of elevated T3 concentrations with more severe PTSD symptoms"

I don't have PMS, but I suffered from some infantile trauma and the same study says that "in non-PMS women, a trauma history was associated with decreased T3 concentrations", and indeed I do have a low fT3...

 

[Neunistiva]

@pattismith Thay's interesting but I never suffered any trauma. Had a pretty uneventful life.

I don't know why I have elevated fT3, but recently I went from having all my lab results normal for years to having some contradictory test results like:

low vit D, low alkaline phosphatase, high fT3, low copper, low potassium, high phosphates...

and most of those things should influence the levels of others in the opposite direction than where they are (such as hypothyroidism, not hyper, is proportional to low alkaline phosphatase, as is high vit D levels etc) but I guess my body didn't get the memo.

 

[lafarfelue]

@pattismith that's really interesting. thanks for posting! I wouldn't be surprised about this being the case at all. I believe I've always had PMS and am now also starting to experience PMDD as my IUD wears off. I have childhood trauma and had multiple traumatic experiences (all of which have given me PTSD and then c-PTSD) within a few years prior to ME/CFS presenting itself fully. I'm adding more testing to my (very very very long) list of things to tackle next.

 

[pattismith]

@pattismith Thay's interesting but I never suffered any trauma. Had a pretty uneventful life.

I don't know why I have elevated fT3, but recently I went from having all my lab results normal for years to having some contradictory test results like:

low vit D, low alkaline phosphatase, high fT3, low copper, low potassium, high phosphates...

and most of those things should influence the levels of others in the opposite direction than where they are (such as hypothyroidism, not hyper, is proportional to low alkaline phosphatase, as is high vit D levels etc) but I guess my body didn't get the memo.

some other abormalities can trigger high fT3, for example inactivation of the MCT8 transporter (only genetic cases are known in studies, but we could assume that some auto-antibodies could block them as well)

https://www.sciencedirect.com/science/article/pii/S2213671118301486

or some antibodies against thyroid hormons can give false thyroid test result with high levels of T3 or T4.

Do you have antithyroglobulin antibodies?

 

[kangaSue]

Thanks for the info (I think! ) No, really, thank you. What sort of doctor would do this? a nephrologist?

I would start with your G.P. and have him listen for this murmur (actually called a bruit) and order a duplex doppler ultrasound test if suspicious to check out the blood flow situation. For a specialist, this is the territory of Vascular Surgeons as well as Nephrologists.

 

[Mary]

I would start with your G.P. and have him listen for this murmur (actually called a bruit) and order a duplex doppler ultrasound test if suspicious to check out the blood flow situation. For a specialist, this is the territory of Vascular Surgeons as well as Nephrologists.

Thanks so much! I doubt if my GP would be interested but could try to talk him into it. Actually I generally see a nurse practitioner. The last time I saw the MD in that office I had to wait over 2 hours past my appointment time to see him -probably closer to 2-1/2 hours- no excuse for this! Another woman waiting ahead of me ended up missing a ride or something because he was so late and no apology at all. So have a very hard time even thinking of going to see him - an appointment with him would be an entire day's expenditure of energy. And he's only a 10 minute drive away.

Yes, I can find another doctor, only where I live, there are almost none to choose from who do more than basic drive-by medicine - blood sugar, cholesterol, etc.

What I want to know is, why can't we call the doctor's office, see how late they're running, and then arrive when they will actually be there to see us? But no, you have to sign in, and waste your time and energy sitting - otherwise you lose your place. Sorry @kangaSue! This has nothing to do with you, am just venting here.

 

[kangaSue]

@Mary Luckily for us in Australia, nurse practitioners aren't a thing yet so we get to see the MD at every visit.

 

[Tally]

@Mary Luckily for us in Australia, nurse practitioners aren't a thing yet so we get to see the MD at every visit.

It seems they are, although I don't know how prevalent it is

https://en.wikipedia.org/wiki/Nurse_practitioner#Australia

 

[CFS_for_19_years]

In the last couple of years I've also become aware that low phosphorous is an issue for me, causing sometimes severe fatigue. I first stumbled across the issue of low phosphorous when I started taking thiamine a few years ago, and after an initial boost in energy for a few days, developed severe fatigue. This was similar to what happened when I started taking methylfolate, only the methylfolate caused my potassium to tank, whereas with the thiamine, it was my phosphorous which tanked. I determined this empirically. The fatigue felt different than low potassium, and it resolved when I increased my phosphorous intake.

I believe both the potassium and phosphorous issues were related, at least initially, to refeeding syndrome. But they are continual and ongoing, which I find a little puzzling, though I know persons with ME/CFS can have trouble keeping intracellular levels of potassium where they should be. Perhaps the same is true of phosphorous?

Low phosphorus is rare since our food supply contains plenty of phosphorus. Are you sure you have confirmed low serum phosphorus? (NOT alkaline phosphatase, which is an enzyme). Kidney patients have to restrict phosphorus and in order to do so they must follow a strict diet.

I know we had a conversation about this earlier:

https://forums.phoenixrising.me/ind...gue-due-to-low-phosphorous.60181/#post-980881
Mary said: ↑
My alkaline phosphates level (part of comprehensive metabolic panel) a few years ago was low, but never flagged by anyone, and low alkaline phosphates can be caused by hypophosphatemia, as well as other things

I said: I think you mean alkaline phosphatase, an enzyme. See https://labtestsonline.org/tests/alkaline-phosphatase-alp

Low levels of ALP may be seen temporarily after blood transfusions or heart bypass surgery. A deficiency in zinc may cause decreased levels. A rare genetic disorder of bone metabolism called hypophosphatasia can cause severe, protracted low levels of ALP. Malnutrition or protein deficiency as well as Wilson disease could also be possible causes for lowered ALP.

Alkaline phosphatase is part of a routine complete metabolic panel and is sometimes abbreviated as ALK PHOS. A phosphate (phosphorus) test is usually ordered by itself (not a part of a panel) when your doctor suspects you could be at risk for having a low or high level.

If indeed you have low phosphorus (phosphate) and NOT low alkaline phosphatase, here is what you need to know:
https://www.merckmanuals.com/home/h...sphatemia-low-level-of-phosphate-in-the-blood

In chronic hypophosphatemia, the phosphate level in blood becomes low over time. Chronic hypophosphatemia usually develops because too much phosphate is excreted. Causes include the following:

• Hyperparathyroidism
  
  
• Chronic diarrhea
  
  
• Use of diuretics for a long time
  
  
• Use of large amounts of aluminum-containing antacids for a long time
  
  
• Use of large amounts of theophylline (used to treat asthma)

[...]
Symptoms of Hypophosphatemia
Symptoms occur only when the phosphate level in blood becomes very low. Muscle weakness develops, followed by stupor, coma, and death.

In mild chronic hypophosphatemia, the bones can weaken, resulting in bone pain and fractures. People may become weak and lose their appetite.

Edited to add:
https://labtestsonline.org/tests/phosphorus

• If there are no symptoms, how will I know if I have an abnormal phosphorus level?
  Abnormal phosphorus levels are usually detected because of the relationship with and effect on calcium levels. Calcium is routinely tested as part of the comprehensive metabolic panel (CMP) and basic metabolic panel (BMP), tests that are frequently ordered as part of a health exam. If you have an abnormal calcium level, your healthcare provider usually will check your phosphorus level.

 

[CFS_for_19_years]

But I read on wikipedia that leaving the blood sample at room temperature for a few hours can cause pseudohypokalemia. I am bedridden and nurse comes take my blood. It definitely takes it a few hours to get to the lab. Now I'm not even aure if I have low serum potassium or if it's just an artefact.

@Neunistiva - that's interesting about leaving blood samples at room temperature causing pseudohypokalemia. On blood work, my potassium is always low-normal. But I get symptoms of low potassium anyways and believe the problem is low intracellular potassium, as Richvank described here

Delayed centrifugation (separation of red cells from serum or plasma) of greater than 2 hours causes INCREASED serum potassium (hyperkalemia). Room temperature is the preferred condition for storage of blood samples prior to centrifuging. Cold or hot temperatures prior to separation of red cells from serum will cause INCREASED serum potassium (hyperkalemia).

Errors in Potassium Measurement: A Laboratory Perspective for the Clinician
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3662091/

Time
Delayed processing, results in exhaustion of available glucose to generate ATP. Since ATP fuels the sodium potassium pump and maintains the gradient across the cell membrane, failure of the pump results in leakage of potassium out of the cell, resulting in pseudohyperkalemia.
[...]

Temperature
Cold temperature inhibits the sodium potassium pump resulting in leakage of potassium. Higher temperatures initially decrease and then increase potassium concentrations, probably related to increased usage and exhaustion of glucose that generates adenosine triphosphate (ATP) for the sodium-potassium pump. Recommended temperature for specimen storage prior to testing is 15-25°C.[2] Specimens should not be stored between 2°C and 8°C, or above room temperature for more than 24 h.[2] Elevations in potassium more commonly observed in samples from doctors’ offices compared to inpatient or laboratory collections, attributed to changes in temperature that the sample is exposed to during transport in winter, have been dubbed “Seasonal Pseudohyperkalemia.”[11,12]

Elevated Serum Potassium Values
https://sci-hub.tw/10.1309/uepqum11wh9p8jny

Delays in Transport and Processing
Whenever there is a delay in specimen transport,
processing, or both, the probability of potassium release
from the cells increases. Laessig et al
have shown that the
serum potassium level increases after 2 hours from collec-
tion. If a delay is unavoidable, the serum should be separated
from the cells into another tube within 2 hours of collection
or, for tubes with a gel separator, the specimen should be
centrifuged before transport.

Transport Conditions
[...]
For conventional transport, the specimens should
be positioned in an upright (stopper-up) position to avoid
adherence of the RBCs to the tube closure and contamination
of the serum with RBCs. However, vertical placement of
tubes might not be possible when specimens are transported
off-site.
[...]
Specimen Storage Temperature
The storage temperature greatly affects potassium
results. Cold inhibits glycolysis, which provides energy for
the sodium-potassium pump that keeps potassium contained
within the cell; without enough energy, the pump activity
slows, which allows potassium to leak out of the cells.
Serum potassium levels increase significantly at tempera-
tures lower than 15°C.
To prevent problems, specimens
should not be kept at temperatures lower than 15°C
unless the serum previously has been transferred into a sepa-
rate tube. The NCCLS recommends that specimens obtained
for potassium testing not be stored at 2°C to 8°C before
centrifugation and separation of serum from the cells.
As is the case with low temperature, exposure of specimens to
temperatures higher than room temperature (22°C-25°C)
affects potassium testing results. Keeping the specimen for
24 hours at a temperature higher than room temperature
(30°C) increases the potassium level.

 

[Mary]

@Mary Luckily

Are you sure you have confirmed low serum phosphorus?

No, I have not confirmed this. As I've written before, I suspected hypophosphatemia after developing severe fatigue after starting to take thiamine. The thiamine initially boosted my energy markedly for 1 or 2 days, then severe fatigue hit. I suspected hypophosphatemia because of refeeding syndrome. Hypophosphatemia is the hallmark of refeeding syndrome. A similar pattern occurred when I started methylfolate - an initial boost in energy followed by severe fatigue, which turned out to be hypokalemia. The fatigue after methylfolate resolved after titrating up to 1000 mg potassium a day in divided doses and I've had to take potassium daily ever since. Actually I'd had symptoms of low potassium before starting the methylfolate but I never knew what it was until I learned about refeeding syndrome.

The fatigue after starting the thiamine felt different, plus potassium did nothing for it. So I suspected refeeding syndrome again, suspected low phosphate, its hallmark, looked up foods high in phosphate, found dairy to be high, drank several glasses of kefir and that particular fatigue dissipated. But it recurs regularly and I've found I have to take a phosphate supplement several times a week, plus drink kefir occasionally and that resolves this particular fatigue.

I don't have blood work for all of this, which is why I did this thread. I would like to see a doctor to see what they can find out about my phosphate levels in particular. I may have phosphate diabetes which is supposed to affect some 10% of persons with ME/CFS. Or it may be something else. Yes, I had one abnormal alkaline phosphatase test which may have indicated low phosphate but I have not had a doctor to work on with this.

Do you know what type of doctor I should see? Maybe I do have hyperparathyroidism - this is the kind of thing I would like to find out but I don't know who to see.

 

[Mary]

@CFS_for_19_years - here's Wikipedia on hypophosphatemia, which states that refeeding syndrome is its chief cause: https://en.wikipedia.org/wiki/Hypophosphatemia

And here are symptoms listed in the same article. Some of these seem rather apt for ME/CFS:

• Muscle dysfunction and weakness – This occurs in major muscles, but also may manifest as: diplopia, low cardiac output, dysphagia, and respiratory depression due to respiratory muscle weakness.
• Mental status changes – This may range from irritability to gross confusion, delirium, and coma.
• White blood cell dysfunction, causing worsening of infections.
• Instability of cell membranes due to low adenosine triphosphate (ATP) levels – This may cause rhabdomyolysis with increased CPK, and also hemolytic anemia.
• Increased affinity for oxygen in the blood caused by decreased production of 2,3-BPG.
• Large pulp chambers in the teeth.

I think it's very likely that hypophosphatemia is not that uncommon in ME/CFS patients, only we have so many varying sources of fatigue, and this is so unusual, doctors don't look for it.

 

[kangaSue]

It seems they are, although I don't know how prevalent it is

https://en.wikipedia.org/wiki/Nurse_practitioner#Australia

The field of Midwifery would be the exception.

 

[BeADocToGoTo1]

Hi @Mary

I stumbled across this old thread based on the ALP discussion in another thread. In case it helps with this discussion and your situation, this is what I wrote there:

Absorption of B6 is complicated, involving phosphorylation and dephosphorylation, oxidation and reduction, amination and deamination, all primarily taking place in the jejunum and ileum portions of the small intestine. So any type of malabsorption or microbiome dysbiosis can also cause issues.

ALP, vitamins B2, B3, molybdenum, zinc and magnesium are all needed to absorb and utilize vitamin B6.

Low alkaline phosphatase ALP can be a sign of malnutrition, pointing to possible deficiencies in vitamins B, C, D, folic acid, zinc, protein, and phosphorous.

It might be worthwhile looking into any form of malabsorption and have a close look at your diet quality. My ALP was quite low before fixing microbiome dysbiosis, SIBO, Candida, taking pancreatic enzymes for exocrine pancreatic insufficiency and fixing nutrient deficiencies.

A more technical read on ALP (although most focus is often on too high a level) here:

https://www.ncbi.nlm.nih.gov/books/NBK459201/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5838368/

 

[BeADocToGoTo1]

Hi @Mary ,

One more thing to consider is that you had mentioned taking a substantial amount of vitamin D supplements. This can also have a negative effect. I had read a report that linked elevated ALP with D deficiency, so perhaps the reverse is also possible. Did you ever have your parathyroid checked, as this helps regulate calcium, vitamin D, and phosphorus levels in the body? These tests would include:

• calcium
• albumin (for corrected calcium calculation)
• ionized calcium (bound to other minerals)
• parathyroid hormone PTH
• osteocalcin (vitamin K dependent calcium binding protein)

Did you ever have phosphoserine metabolite show up in one of your tests, perhaps an OAT or Genova FMV?

 

[Mary]

It might be worthwhile looking into any form of malabsorption and have a close look at your diet quality. My ALP was quite low before fixing microbiome dysbiosis, SIBO, Candida, taking pancreatic enzymes for exocrine pancreatic insufficiency and fixing nutrient deficiencies.

Hi @BeADocToGoTo1 - thanks for weighing in here! I have been extremely careful with my diet for over 20 years. I've been taking betaine HCL with pepsin for almost that long. Before I started the betaine HCL, I had a couple of different digestive issues: malabsorption, my gallbladder was inflamed or just not working right, and my liver got overloaded with toxins (I think primarily from chemical solvents I had had heavy exposure to on a job years ago). After doing a liver detox (which was rough) and starting to take betaine HCL with pepsin, my digestion improved enormously. It's in good shape. I was tested for SIBO almost 4 years ago and it was negative. I don't have symptoms of candida either. I don't have any digestive symptoms actually.

I only tested low in ALP once a few years ago. The rest of the time it's been in the normal range. I take a full complement of B vitamins and the other nutrients you mentioned.

Did you ever have your parathyroid checked, as this helps regulate calcium, vitamin D, and phosphorus levels in the body? These tests would include:

• calcium
• albumin (for corrected calcium calculation)
• ionized calcium (bound to other minerals)
• parathyroid hormone PTH
• osteocalcin (vitamin K dependent calcium binding protein)

Did you ever have phosphoserine metabolite show up in one of your tests, perhaps an OAT or Genova FMV?

I don't think I've had my parathyroid checked. And I have not had those other tests. Several months ago I bit the bullet and went to see an endo - my first. I wanted to talk to him about my low phosphate issue. I never got a chance. He told me ME/CFS was due to stress and that there will be no research done on it because it's not real. I tried to show him the research I'd brought and he wouldn't look at it. I tried to explain about refeeding syndrome and he cut me off and said that people in Auschwitz are the type of people who get refeeding syndrome.

I had wanted to talk to him about phosphate diabetes, after explaining about my low phosphate issues, but never got the chance.

So, when I get my energy together enough, there is another endo I want to see who I have to pay cash for, who is close to 2 hours away. It will be a physical ordeal to see him, but he is supposed to be very good. I just have not been able to bring myself to make that appointment. Just answering his questionnaire alone before making the appointment will take a fair amount of energy.

I'll make a note of all the tests you suggested - thank you! Your name is very apt here! We do have to know exactly what we're doing before we go see a doctor, and then also be lucky enough to hit upon one who will actually listen to us. Clueless doctors waste so much time, money and energy!

About vitamin D - I get my levels checked annually and they're always in the normal range so I don't think I have an excess vitamin D problem.

 

[BeADocToGoTo1]

Hi @Mary

Sorry about your endo experience. It is extremely hard to find a good one who is up to date and looks at things comprehensively. The first doc I went to when my health started to decline was also an endo, who completely misdiagnosed me and cost me many more years of decline. I truly hope this next one will be better for you.

But, I find that docs generally are more helpful when you come with a printed list of symptoms, a timeline or progression of symptoms, and recent test results, and do not mention ME/CFS or what you think it is at all. Presenting the symptoms and let them do the doctoring seems to work better for their ego. It is a no-win situation by starting with ME/CFS, as their training and medical board does not consider it treatable, if it even acknowledges it. The printing of bullet point lists also helped me remember everything I needed to come across without having to stress that I would forget a salient point during the appointment.

Vitamin D, K, Phosphorus and Calcium

The parathyroid tests are very standard, and every primary care physician or family doctor should be able to order them for you, under insurance coverage. Your parathyroid tries really hard to balance the calcium and phosphorus levels in the body, and vitamin D has an impact on the process.

Too much vitamin D supplementation (i.e. >400IU from pills for extended periods) when you are not deficient can have a negative impact on your body, including higher blood calcium levels, achiness, pains and even cancer. There was a large scale study done recently. Do you also take calcium supplements, as that was recently in a study as causing harm as well? Calcium through food was found to be great, but supplementation had adverse effects. Likely due to all the cofactors needed. Similar story with vitamin D. Since you are not deficient, are you still taking D?

I used to take 5000IU daily when deficient, but continued way too long, and it backfired. Now I instead go outside for a walk to have UV light and my cholesterol (7-dehydrocholesterol) be used to manufacture some endogenously, or I will have some cod liver oil or fish. No more pain from vitamin D supplements and better absorption that way.

Even small increases in calcium in the blood can cause issues. High calcium in the blood can cause issues like high blood pressure, bone loss, and kidney damage.

Also fortified processed foods often contain synthetic vitamin D and calcium like certain cereals, juices and non/low fat milk, which can add another dose.

Vitamin K is also important in utilizing calcium for bone strengthening. So if you are deficient in K, it will play a part in this cycle, hence the osteocalcin test. A plain vitamin K test might also be worthwhile.

A more technical read on the parathyroid:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2486454/

 

[Mary]

Hi @BeADocToGoTo1 - thanks for all your suggestions re seeing a doctor. I'm sure you're right, but it rankles that I have to basically lie to try to get any help. The endo I'm going to see (finally made an appt this morning!) was recommended to me by someone who made great strides in recovering from ME/CFS, so I'm just going to be straight with him. You're right, any doctor could run the parathyroid tests. I just don't have a decent doctor to do it so am going to ask the endo about it. If he won't do the testing through Medicare, which would pay for it, then I will scrounge up someone to do it. I wonder if doctors have any clue what we go through in trying to find someone trustworthy and competent? Probably not.

And I want more than the standard parathyroid testing - I want someone to look into the possibility of phosphate diabetes, and your regular MD is just not going to know anything about this.

I don't take calcium supplements, though I used to, when it was the party line to take calcium. I learned a few years ago that the calcium was probably contributing to my insomnia. I do take a lot of magnesium however,.

I still take the 5000 iu of vitamin D and will request to get my vitamin D levels retested. I do get it checked every year and it is in the normal range. I can't go for a walk most days. Many days I can't even go outside. To be honest, I never go for a walk. If I have energy, then I have to use it for laundry or grocery shopping, etc., and then rest, rest, and rest some more. Once in awhile I go in the pool where I live and get a lot of vitamin D that way but can't really swim much, and each time I go in the pool I have to take a shower and wash my hair after, which takes a lot of energy, so it's a big undertaking.

I rarely eat processed food. I never eat cereal or drink milk. I do take vitamin K. Thanks again for all the info! I think I lucked out in getting an appt with the new endo the end of this month, 4 weeks from now. Will cross my fingers!

eta: In the article you linked above, it says that one of the causes of hypophosphatemia is "post feeding syndrome" - I assume they mean refeeding syndrome. This is the theory I'm going on. I first became aware of a phosphate deficiency when I started taking thiamine, got a boost in energy, followed by severe fatigue, which was relieved by kefir and a monosodium phosphate supplement, which enabled me to keep taking the thiamine.

 

[BeADocToGoTo1]

Hi Mary,

In case you had not seen this on some of the other threads, these short videos are worth watching. Dr. Phinney even briefly mentions refeeding in the 3rd one. Lots of good info on that site too.

https://blog.virtahealth.com/dr-stephen-phinney-ketosis-ketogenic-diets/

I started reading about the phosphate diabetes, since you had mentioned it. What struck me so far is that diabetes can cause low phosphate and low ALP. Perhaps it then causes a vicious cycle. It seems that too high a carb intake, too much insulin production, increased insulin resistance can impact phosphate levels. I really am starting to wonder how many ME/CFS sufferers have had low ALP (and many other symptoms) due to too much carbs in the diet for their bodies to handle, with subsequent chronic glycation of cells, systemic inflammation and oxidative stress. Of course just one piece in the big puzzle, but I think it also ties to what Dr. Neil McGregor is looking into with some of his metabolic research.

Do you keep track of blood glucose or ketones using a simple meter that uses a drop of blood to see the impact of your food? Do you know how many grams of carbs you eat or drink per meal and day? Have you had fasting A1c, C-peptide, insulin levels checked recently? Sometimes the level of carbs might seem low, especially compared with most everyone around us these days, but for your own body might still be too high. Do you have some high carb elements in your diet such as fruit, rice, potato, pasta, starch, bread, juices?

I remember you had mentioned trying a ketogenic diet a while back. Sometimes these diets will fail if it is done in extremes and unsustainable fashion. Have you tried doing it slowly, based on e.g. VirtaHealth (Dr. Phinney) or Primal (e.g. Mark Sisson, Dr. Peter Attia), which is sustainable?