Post-Transplant Nutrition: Protein, Fluids, Potassium, and Food Safety

Post-Transplant Nutrition: Protein, Fluids, Potassium, and Food Safety

Post-Transplant Nutrition: Protein, Fluids, Potassium, and Food Safety

Diet is one of many challenges that patients face post-transplant – the combination of requirements and restrictions can be difficult to navigate. To help, CareDx partnered with Molly Chanzis, a Registered Dietitian at New York-Presbyterian Weill Cornell Medical Center specializing in medical nutrition therapy and nutrition counseling specifically for transplant patients.

We hosted a webinar with Molly focused on diet and nutrition post-transplant; this article has been adapted from Molly’s presentation. We focus on the following topics:

  • Protein intake
  • Fluid intake
  • Potassium intake
  • Food safety

Protein Intake

One of the most common diet questions patients have after transplant is about protein. It’s something that’s usually emphasized both in the hospital and in the clinic setting because protein needs right after transplant are much higher than usual. They can be double your normal needs, or sometimes even a little bit more. The reason is your body is healing – you just had a really big surgery and protein helps the healing process. Patients are also often on high doses of steroids which also increase protein needs. So it can be challenging during this phase to get enough protein, especially if your appetite is limited or you have other procedures you need to do that are keeping you from eating.

Once you leave the hospital and your steroid dose decreases, your protein needs will go down to 1.2 to 1.5 grams of protein per kilogram of body. Then longer term, a few months to years after transplant, your protein needs are about 1 gram per kilogram of body weight.

You may be seeing all these numbers and thinking, what does that mean for me? I don’t even know my weight in kilograms. If you have your weight in pounds, divide by 2.2 to get your weight in kilograms. Then multiply it by the expected grams of protein per kilogram of body weight depending on your stage post-transplant.

Fluid Intake

Fluid intake is another big topic after transplant and it can be especially challenging if you had to restrict your intake before transplant. For example, many patients who were on dialysis or had liver disease with ascites and edema needed to be on a fluid restriction.

It can be really hard when you get your transplant and suddenly you’re being told you need to drink more because it’s been so ingrained in you for many years not to drink too much. So this can be a big learning curve.

Most people will need about two liters of fluids per day. This can vary depending on your size –  people on the smaller end may be able to get by with a little less, some bigger people might need more – but two liters (equivalent to 64oz or 8 cups) is a great place to start, and then your treatment team can certainly help you adjust from there based on how well you’re retaining fluid or how much urine you’re making.

Sugary fluids should be limited. Limit doesn’t mean never, it just means not all the time – not too much. Think soda, sweet tea, sweetened coffee, drinks and even juice. Even though juice is made from fruit, it contains a lot of sugar, so these things should really be consumed infrequently or in small portions. You’ll notice the juices they give you in the hospital are always small, four ounce cups. So that’s an example of what a serving could be. Other sweetened drinks try to drink more sparingly.

Caffeine is generally ok, Cornell recommends capping it around three cups of coffee a day. In this case, “cups” means the size of a small coffee cup, around a 6 ounce serving (not three Starbucks Ventis).

If you’re getting tired of water because everyone is telling you to drink so much of it, and your needs have gone up so much, there are ways that you can spice it up to make it a little more exciting. One way is just to add fresh fruit into water. Make sure that you wash it first, but you can put in sliced lemon, lime, orange, pineapple or cucumber. Even certain herbs can go nicely like mint.  Flavored seltzer water is also a great option.

So if the thought of drinking two plus liters of water in a day seems like a lot, consider some of these options.

Potassium Intake

Potassium is also a topic that comes up a lot, whether it’s low or high, because a lot of medications can affect potassium levels. A lot of kidney patients are already familiar with potassium because this is a nutrient that often needed to be restricted or avoided with kidney disease; recipients of other organs may not have ever had to think about potassium intake before.

Certain transplant medications such as tacrolimus and sulfamethoxazole can increase the levels of potassium in your blood. Others like diuretics can decrease it; so you could have high or low potassium depending on your specific situation.

Some foods that are high in potassium include bananas, potatoes, sweet potatoes, and other kinds of root vegetables. Potassium is also found in plantains, tomato sauce, tomato juice, and in cooked dark leafy greens like cooked kale, spinach, and collard greens. Note that with the greens, you tend to eat a lot more when they’re cooked because they shrivel up. Coconut water also has a lot of potassium, as does orange juice and avocados.

One tip to add is the concept of leaching your potatoes. It really works for any kind of root vegetables, but if you cut it up into cubes, soak it in water overnight for 24 hours (the longer the better), a lot of the potassium will come out into the water, so it’s a way that you can enjoy these foods without getting as much potassium. Just make sure you dump out the water before you cook it –  if you involve that water in cooking, you’re still going to end up eating it.

And then a last thing to keep in mind is that while frustrating, a low potassium diet after transplant is usually (although not always) temporary.

Food Safety

Food safety is often a main focus at the hospital immediately after transplant because it’s not something patients have had to think about before. As a transplant recipient, food poisoning is something you have to be really aware of because your immune system is weaker after the transplant. This is ok, it’s weak on purpose so that your body doesn’t fight off your new organ, but you do have to be especially careful that you’re preparing food in safe ways and staying away from high risk foods that could potentially make you sick.


  • Fruits and vegetables always need to be washed
  • You cannot eat sprouts raw (not Brussel sprouts, but more like bean sprouts and alfalfa sprout)
  • Be very careful buying pre-cut fruit like watermelon or pineapple from the store or getting salads from restaurants. You never know if the people handling the food wash their hands or wash the produce before cutting it

As patients get further out from transplant, some of these things could be ok, but are definitely things to be careful with in the beginning.

Foods that interact with medications

And then there are a few different fruits that interact with tacrolimus: grapefruit, pomelo (if you’re not familiar, pomelos look like grapefruit, but are bigger and a little bit more green (they are in the same family), pomegranate (including pomegranate juice), star fruit, and Seville orange.

Dairy and meat

Any kind of dairy products that you eat (e.g. milk, yogurt, cheese, etc.) need to be pasteurized. This does not apply if the meal is fully cooked. So if you had a baked ziti in the oven for 45 minutes, you can guarantee that cheese is fully cooked and any bacteria was killed. But if you’re eating cheese and crackers or cheese cold in some way, it needs to be pasteurized.

Eggs also need to be fully cooked, so that means no runny yolks, no over easy and just looking out for any foods that might be made with raw eggs. For example, the traditional Caesar salad dressing recipe has raw eggs.

Meat and seafood need to be fully cooked. The temperature to which they need to be cooked to depends. The threshold, for example for poultry, is higher than that for red meat. Lunch meat, cold cuts or deli meat can pose a risk because of the slicer machine that they go through. The machine may not necessarily be washed or cleaned after every use. So lunch meats should be heated up before you eat them.

Spoilage and cleanliness

Another guideline to stay safe is avoiding buffets or any type of food that’s been sitting out for longer than two hours. This isn’t just buffet restaurants, but also applies to social gatherings where platters sit out for an extended period of time.

And even making sure your groceries are put away when you get home – don’t leave them out for more than two hours and make sure your leftovers after dinner are put away.

Finally, apply food safety in the kitchen by washing your hands, especially after you handle raw meat. Avoiding what’s called cross-contamination, for example, if you have some raw burgers on a plate and you’re going to grill them, don’t put the cooked ones back on the same plate, because you could get sick from that, so avoiding those types of scenarios.

For transplant-friendly recipes see

Nutrition requirements will vary based on individual patient circumstances. Always seek the advice of your physician or medical team with any questions you may have regarding your specific medical condition. The information is not intended or implied to be a substitute for professional medical advice from your healthcare provider. 


  1. Hasse, J. Matarese, L. Solid Organ Transplantation. The ASPEN Core Curriculum. ASPEN. 2017.
  3. Academy of Nutrition and Dietetics. Nutrition Care Manual®. 2020.
  4. USDA. Food Safety: A need to know guide for those at risk.