14 Healthy Foods People With Kidney Issues Should Still Avoid
Kidneys are one of the vital organs in the
human body. Unfortunately, they are also among the most susceptible to
damage and often take the first hit from chronic diseases like
hypertension or serious infections, both bacterial and viral. Those who
have sustained kidney damage or suffer from chronic kidney disease
should watch their diet to keep their kidneys and prevent other adverse
health effects. Certain foods, even those considered healthy for most
people, should be avoided by those who have kidney problems. In this
article, we’ll explain which foods you ought to exclude from your diet
to protect your kidneys, and why it’s important to do so.
General Considerations and Tips
The kidneys play several important roles in human health, such as
filtering blood, regulating mineral levels, maintaining hormone levels,
and removing waste products. When they are damaged, all or some of these
functions are affected, and it might be more difficult for liquids,
excess minerals, and waste products to be eliminated from the body. This
is when diet regulation comes in, as it is capable of excluding certain
minerals and other nutrients typically processed by the kidneys and
prevent further damage.
In addition, choosing foods good for kidney health will help improve
kidney function. The extent to which you should limit certain foods will
depend on the severity of the kidney damage, with serious cases
requiring dialysis, a strict dietary regimen, and other medical
interventions you ought to discuss with a doctor. Earlier stages of the
disease, on the other hand, may require fewer dietary restrictions.
Some of the key dietary tips to keep in
mind are:
1. Limiting daily sodium intake to 2g or less.
This means avoiding added
salt, soy sauce, packaged foods, and fast foods, among other things.
Signs that your kidneys cannot filter out excess salt from your diet
include high blood pressure, swollen ankles, and shortness of breath. In
severe cases, fluids can build up in the heart and lungs.
2. Reducing Your Phosphorous Intake to about 1,000 mg a day.
Phosphorous
is essential for healthy bones and teeth, and it helps cells to repair
themselves, but excess levels of the minerals that don't get filtered
out by the kidneys may have the opposite effect and lead to an increased
risk of heart disease. This is why dark-colored sodas are not
recommended for people with damaged kidneys, as these often contain
phosphorous.
3. Watching Your Potassium Intake.
Potassium is another mineral
regulated by the kidneys. While it is important to keep your muscles
healthy, excessive levels of potassium (over 2,000 mg a day) in the
blood can lead to serious heart issues, so it is recommended to watch
your potassium level if you suffer from significant kidney damage.
Below, we list 14 generally healthy foods that contain a lot of sodium,
potassium, phosphorous, or other ingredients that can be harmful to
those suffering from kidney issues.
1. Bananas
Bananas are well known for their high
potassium levels, with just one medium fruit containing 422 mg of
potassium on average. If you want to keep your potassium intake below
2,000 mg a day, it may be difficult when eating this tropical fruit.
Other tropical fruits that also contain a lot of potassium are
pomegranates and coconut water, to name a few.
2. Spinach
It's not just spinach that can harm your
kidneys, other leafy greens like Swiss chard and beet greens have a
similar nutrient profile. Like bananas, these greens are high in
potassium, with 1 cup of the fresh greens containing up to 290 mg. In
addition, these greens contain a lot of oxalates, which can accumulate
in the kidneys and cause kidney stones, reducing the kidney function
even further.
Cooking spinach will not reduce its potassium content, and it can be
quite easy to consume a lot of it in cooked dishes that contain some
spinach (e.g. 1 cup of spinach reduces to just 2 tablespoons of cooked
spinach).
3. Certain Dried Fruit
Dried fruits are a common healthy snack,
with dietitians often recommending them instead of sweet treats.
However, many varieties of dried fruit can contain a lot of potassium in
a relatively small volume, so it's easy to increase the recommended
daily intake of potassium while snacking on dried fruit. For example,
just 2 pitted dates containing 334 mg of potassium. Other dried fruit
high in the mineral are prunes, raisins, and dried apricots.
The dried fruit most beneficial for those suffering from kidney problems
is dried cranberries, a 1/3 cup serving of which contains just 16 mg of
potassium.
4. Brown Rice
Brown rice is a whole grain that's quite
high in both potassium and phosphorous, with just one 1/2-cup serving of
cooked brown rice having 78 mg of potassium and 75 mg of phosphorus.
Processing reduces the amount of these minerals in rice, so the same
serving of white rice will contain just 35 mg of phosphorus and 29 mg of
potassium.
Still, white rice also contains less of the other nutrients, so instead
of replacing brown rice with white rice, it's better to opt for other
grains, such as buckwheat, bulgur, or couscous, that both have a much
lower phosphorus content and contain other beneficial ingredients. Keep
in mind that the popular grain, quinoa, is even higher in phosphorus and
potassium than brown rice, so it's not a good replacement.
5. Oranges and Orange Juice
Like other tropical fruit, citrus fruit,
especially oranges and grapefruit, contain a lot of potassium, as do
their juices.
One orange or grapefruit both contain around 333 mg of potassium. Just
one 240 ml cup of orange juice contains even more - 473 mg of potassium,
which is more than a quarter of your daily intake of the mineral.
You can replace orange juice and the fruit itself, you can opt for
grape, apple, or cranberry juice and the respective fruit, all of which
are more beneficial for the kidneys.
6. Canned Foods
The main problem with canned foods when it comes to kidney health is the
high sodium content. Salt is necessary for preserving foods for a long
time, so there is no way to avoid it, especially if you're dealing with
canned soups or readymade meals. If you depend a lot on these foods,
it's best to choose the low-sodium varieties when shopping for canned
goods.
You can also rinse canned vegetables, like peas, beans, and tuna with
water before eating them, which can reduce the sodium content by 33–80%.
7. Seafood and Other Animal Sources of Protein
People with serious cases of kidney damage are often asked to reduce
their intake of animal protein, such as red meat and poultry, but
especially seafood, mainly because chronic kidney damage can reduce how
well the body can eliminate protein side products. Needless to say,
processed meats are off the table, too, as these typically contain way
too much salt even for people without any kidney problems. Dairy
products are likewise not recommended, as they contain phosphorous and
potassium in high quantities, and certain cheese varieties can also be
quite high in sodium.
Certain seafood varieties, such as mollusks, squid, and octopus can also
contain up to 85% of the recommended daily intake of phosphorous in
just one serving, so they can be quite difficult to incorporate into a
low-phosphorus diet. Also be wary of canned fish, which can be high in
salt content.
8. Apricots 
Apricots are another fruit people with a renal diet should best avoid,
since both dried and fresh apricots are quite high in potassium: 1 cup
of fresh apricots has 427 mg of potassium, on average. The same applies
to apricot juice or nectar, so we recommend opting for some of the
kidney-friendly juice substitutes we mentioned earlier.
9. Olives and Pickles
Fermented foods like kimchi, olives,
pickles, and sauerkraut can do amazing things for one's gut health, but
fermentation, unfortunately, requires the use of plenty of salt,
rendering these foods potentially harmful for people with kidney
problems. To put things in perspective, depending on the brine, 1 pickle
spear can sometimes contain as much as 300 mg of sodium, or even more.
Be wary of low-sodium varieties of pickled foods, too, as even these are
often unsafe for those on a renal diet.
10. Whole Wheat Bread
Normally, whole grain bread is considered a
healthier choice, but the same rule doesn't apply to those with damaged
kidneys. Like brown rice, whole wheat bread is made of whole grains,
which may contain a lot more beneficial nutrients and fiber than white
bread, but along with it also comes double the amount of potassium and
phosphorus, too.
Thus, those who are watching their potassium and phosphorus intake
should actually opt for white bread, which is somewhat counterintuitive.
You can also try other bread varieties that don't contain wheat, such
as cornbread but make sure to take sodium content into account, too, as
most bread varieties do contain a lot of salt.
11. Tomatoes
Tomatoes are another one of those staple
foods that are, unfortunately, unavailable to those on a renal diet
since they contain a lot of potassium: 1 cup of tomato sauce contains
over 900 mg of it. You can replace a tomato sauce with a roasted red
pepper sauce to go with pasta or other dishes, which offers
significantly less potassium per serving.
12. Certain Breakfast Cereals
Choosing a breakfast cereal can be a
daunting task for those with chronic kidney problems, as many cereal
varieties available on the market contain dangerously high levels of
potassium. In addition, a recent study conducted by the National Renal
Foundation also showed that many companies misrepresent potassium levels
in their products.
For this reason, opting for breakfast cereals made of corn or rice flour
is the safest choice for those suffering from kidney problems, as the
whole wheat or whole oatmeal choices typically contain more significant
potassium.
13. Potatoes and Sweet Potatoes
Potatoes and sweet potatoes are among the
most potassium-rich vegetables, with 1 medium baked potato offering 610
mg of potassium, a similar sweet potato containing only slightly less -
541 mg. Luckily, there is a trick that will help you reduce potassium
levels in potatoes and yams by 50%.
Soaking and boiling the vegetable will help reduce its potassium
content: simply cut the vegetable into thin pieces and soak for several
hours, and then boil them for at least 10 minutes. Do keep in mind that
you will still need to control the portion of the potatoes and yams you
consume, even if you soak them.
14. Avocados
The last, but definitely not the least item
on this list is the avocado - a constant feature in healthy recipes.
Unfortunately, avocados are also among the most potassium-rich foods,
period, containing more than double the amount of the mineral compared
to bananas. 1 cup of avocado contains 727 mg of potassium, more than a
third of the recommended daily intake for people with chronic kidney
damage, so try to stay away from them.