Is watermelon good for kidney patients? Should you eat more watermelon if you have kidney disease? As with most answers in kidney nutrition, the answer is “it depends”. Read on to learn more about watermelon and it’s benefits for kidney health!
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Watermelon For Kidney Patients
As I always say, there is no single diet that is best for kidneys. A healthy kidney diet is very different based on your diagnosis, stage of kidney disease, labs and other medical history.
I’ll break down watermelon and kidney health into two big considerations: watermelon for kidney disease and kidney stones.
Watermelon and Kidney Disease
What about kidney disease? Is watermelon good for people with kidney disease?
In short, yes! Watermelon is good for kidney disease. Why is this?
Fruits & Veggies for Kidney Disease
The main reason why watermelon is good for kidney disease is that it is simply a fruit! People who eat plenty of fruits and vegetables tend to have better blood control, lower acid levels and slower progression of kidney disease. (1) It is a win-win!
Fruits and veggies are also packed with fiber! Of course, fiber helps keep you regular and prevents constipation. In kidney disease, constipation can be much more than a nuisance! Constipation may increase potassium levels and uremic toxins. (2) It has also been linked to a greater risk of end-stage kidney disease, heart disease and mortality. (2) So, watermelon can be a great way to add some extra fiber and help keep you regular!
Watermelon also has a ton of healthy vitamins and minerals like vitamin C and vitamin A. Watermelon also has a compound called “lycopene” in it, which has been linked to a lower risk of cancer. (3)
What About Potassium?
Some people with kidney disease need to limit how much potassium they eat. But, for others, a high potassium diet can be beneficial. Ultimately, people who have high blood potassium levels need to limit potassium.
Watermelon has a moderate amount of potassium in it. One cup of diced watermelon has 170mg of potassium. No matter what your potassium needs are, watermelon can fit into a kidney friendly plan for you!
Watermelon and Creatinine
Creatinine is measured in your blood. It is a marker of how well your kidneys are working. Creatinine is a key piece of the GFR (glomerular filtration rate) equation, which estimates your kidney function. A higher creatinine level may mean your kidneys are not working as well as they should.
Watermelon doesn’t have a direct impact on creatinine. Eating more watermelon will not reduce creatinine levels. However, eating a kidney friendly diet, that includes plenty of fruits and vegetables (including watermelon!), can help stop creatinine from going up.
Watermelon and Kidney Stones
Watermelon is also a good fruit to add to your diet if you suffer with kidney stones. In fact, one small study found that watermelon pulp reduced the crystallization of calcium and oxalate in rats. (4)
If you need to limit how much oxalate you eat, watermelon is also a good choice! One slice of watermelon only has 1mg of oxalate.
In general, eating plenty of fruits and vegetables is one of the most important things you can do to prevent kidney stones. (5) (6) Fruits and vegetables are packed with citrate and other powerful kidney stone inhibitors like phytate. (7) They can also help reduce the amount of acid in your urine, which can help prevent the most common types of kidney stones. (7)
Balanced Diet Above All Else
Great! So we know that watermelon is a good choice for nearly all kidney patients! Does this mean that you should start downing all the watermelon in sight? Of course not.
Watermelon is not necessarily any better for people with kidney disease compared to other fruits. Healthy eating is all about putting together well balanced meals and snacks, not eating one specific food.
It is much more important to focus on a variety of healthy fruits and vegetables for kidney health. Watermelon is only a piece of the puzzle!
Fruit & Diabetes
Is watermelon safe for people who have diabetes? Doesn’t it have a lot of sugar?
As all fruits, watermelon does have some sugar (or, carbohydrate) in it. But, healthy eating for diabetes is not about completely avoiding carbohydrate. Instead, it is all about getting carbohydrate from healthy foods like fruit, whole grains and dairy. It is also important to eat balanced meals that include protein, fiber and fat in addition to carbohydrate.
A Registered Dietitian can help you understand how to safely incorporate watermelon into any diabetes friendly eating plan!
Watermelon Kidney Cleanse
I found multiple recommendations online for watermelon kidney cleanses. Among other recommendations, most of these involve eating only watermelon for a few days. These watermelon kidney cleanses claim to do everything from ridding the body of toxins to improving kidney function.
There is ZERO research to suggest that a watermelon kidney cleanse will help kidneys. In fact, a watermelon cleanse could harm kidneys by causing severe dehydration. In addition, one whole watermelon has about 5,000mg of potassium. If you are prone to high potassium levels, this dose of potassium could cause irregular heart beats and even death. It is not unheard of for a watermelon kidney cleanse to recommend eating an entire watermelon.
As a reminder, there is no detox or cleanse that is supported by research. Your body doesn’t need help getting rid of toxins. The kidneys and liver do a great job of getting rid of waste.
Any nutrition recommendations that suggest removing an entire food group from your diet, even for a short amount of time, is a red flag. This is especially true for diets that suggest eating only one (or a handful) of foods. In addition to dehydration, these restrictive diets can cause malnutrition, low blood sugar, low blood pressure and other dangerous side effects. Ask your dietitian before starting any diet plan.