Potassium / sodium (salt) ratio

[Mr. PC]

Bananas are very high in potassium, which I've read can be a problem in conjunction with low sodium diets.

[RRM]

Individual foods do not have to contain the right ratio for our body, because we get all the required nutrients from eating different foods.
For example: we get substantial amounts of vitamin C, beta-carotene and sugars from fruits,
and substantial amounts of protein, vitamin B12 and zinc from animal foods.
But that does not mean that fruits contain too little zinc, or that animal foods too little vitamin C.
It just means that you need a balanced diet of both fruits and animal foods.
Equally so, fruits are low in sodium, indeed, but animal foods are not.

Fruits are just low in sodium, and not high in potassium,
so that the potassium:sodium ratio in fruits is significantly higher, indeed.
Most fruits contain 2 or 3 mg sodium / 100 g., but bananas contain 1 mg,
so that their ratio is higher as well, naturally.

Potassium : sodium (sodium=1) in fruits

393 banana
322 brazil nuts
316 watermelon
227 walnuts
175 mandarin
168 avocado
158 peach
157 orange juice
139 apricot
131 raspberry
130 plums
126 orange
120 figs
82 pineapple
74 kiwi
60 pear
59 strawberries
48 apple
38 mango
21 dried figs
19 dried dates
17 muskmelon
11 coconut

But does that matter?
Does it have a significant impact on your dietary potassium:sodium ratio?
Probably not, as the sodium lacking (compared to other fruits: 10 mg per kilogram of bananas), is readily compensated by other foods,
because the amount is relatively small.
Egg yolk and salmon, for example, contain 51 mg sodium / 100 g.

Potassium : sodium (sodium=1) in some other foods

9.7 pheasant
7.5 horse meat
7.3 salmon
5.4 beef
4.8 turkey
4.3 lamb
4.3 chicken
4.2 mackerel
3.7 human milk
2.7 egg yolk
2.5 to 0.4 oysters

And if you feel your all over potassium:sodium ratio is still off,
you may add a pinch of salt to avocado, for example.
Dehydrating / drying fruits is also effective, as after dehydration the potassium:sodium ratio is about 6-fold lower.

[abicahsoul]

I was under the impression that Sodium is not an issue (nothing we really 'need' to have, or make sure we have.).
When you look at rehydration solutions (the kind you use to rehydrate e.g. when you have diarreah, vomit, high prolonged fever and sweating, and some also use it for training when losing a lot of water due to sweating..) it is always potassium and some kind of sugar.. no sodium..
As far as I have understood potassium is good for ya, in what way would it be bad?

[RRM]

I was under the impression that Sodium is not an issue (nothing we really 'need' to have, or make sure we have.).

Sure, we need it, but we dont need to make sure we have it, as we will.
In modern diets, sodium is widely over-represented. And in this diet, animal foods are a good source.
If blood sodium levels are low, aldosterone decreases the excretion of sodium in the urine.

As far as I have understood potassium is good for ya, in what way would it be bad?

Excess potassium would kill cells, damage gastric or intestinal mucosa and eventually cause heart failure,
and may also decrease the availability of vitamin B12,
but luckily excess potassium is readily deported, as it is moved passively. Bennett CM
So, no worries here, unless your kidneys (which control potassium excretion) are failing.
The pool of potassium in our cells is very large, about 30 times as large as the amount of potassium in our blood,
so that its very easy to maintain the right blood-potassium levels.

The potassium : sodium ratio is essential regarding the osmotic balance between cells and the interstitial fluid,
and their distribution is mediated by the Sodium/Potassium ATP pump, using energy to pump 3 sodium ions out of the cell
and 2 potassium ions into the cell, which creates an electrochemical gradient,
which is essential for nervous cells, for impulse transmission.

[panacea]

Just by eating potassium rich foods it will flush out excess sodium from your body.

[RRM]

Doesn't too much sodium lead to high blood pressure?

In people that already have hypertension, high sodium is associated with elevated blood pressure, indeed.
But its not just about sodium. Thats why the effect of reducing sodium intake in prehypertension is not that big.
Rats fed an early and long-term high-salt diet had only minor changes in blood pressure. cordaillat M et al
With a reduced dietary sodium intake, 11 long-term trials showed (in humans) only a small decrease in blood pressure (and only in median systolic and not diastolic). Dumler F
"the long-term impact of reduced salt intake on blood pressure... remains to be defined."
"The recent Trials of Hypertension Prevention follow-up study found ... small changes in blood pressure" Cook NR
The role of protein intake and various hormones are at least as important.
Excessive energy intake and obesity are major causes of hypertension. Savica V et al
Thats because excessive energy intake derails the regulatory processes that maintain the right levels.

She also said that exercise and a healthy diet were ways to reduce my blood pressure and keep it in the normal range.

The reported effects of exercise independent of weight loss on blood pressure are inconsistent.
The effect of weight loss by itself is greater.
Studies found no evidence of hypertension lowering effects of 'healthy diets' if not specifically designed to reduce hypertension (as DASH is). Toledo E et al

Just by eating potassium rich foods it will flush out excess sodium from your body.

Findings from controlled trials of increased potassium show only modest blood pressure lowering effects and are less conclusive. Hedayati SS et al

[Kasper]

What would be a healthy ratio of Potassium:Sodium?
I'm searching for the Na:K ratio of human milk. I read (read: quickly scanned) one study, and one interesting fact: "Milk sodium content was apparently independent of dietary sodium." The mean Na:K ratio of human milk was 0.52 in week 3.5-6 and after 20-32 weeks the mean value was 0.41.

Dehydrating / drying fruits is also effective, as after dehydration the potassium:sodium ratio is about 6-fold lower.

I don't understand how potassium can get lost by dehydration. How does this happen ?

[RRM]

"Milk sodium content was apparently independent of dietary sodium."

Yes, thats (more or less) true for many (essential) ingredients in breast milk.

The mean Na:K ratio of human milk was 0.52 in week 3.5-6 and after 20-32 weeks the mean value was 0.41.

The average levels in "Food Composition and Nutrition Tabels" for after 2 weeks are (in mg / 100g): 12.66 : 47.36, which is only 0.27
6-10 day post partum is 29 : 64, which is 0.45
2nd to 3rd day post partum is 54 : 64 (Na:K), which is 0.84
At least the trend is a decrease with time.

Dehydrating / drying fruits is also effective, as after dehydration the potassium:sodium ratio is about 6-fold lower.

I don't understand how potassium can get lost by dehydration. How does this happen ?

Good question. I dont know. I just noticed the results.