As a bodybuilder with one kidney, I often get asked the same questions from kidney cancer survivors or people with kidney health concerns about protein, exercising, supplements, and water. So, I decided to round all them up in one place.
Q: I want to get into bodybuilding, but I keep reading conflicting advice on how much protein to eat. What’s your take?
A: Here’s the thing: most coaches are wrong about protein’s impact on the kidneys—and so are most doctors. It’s true, research does show that you can eat a high protein diet (defined as 2 to 2.2 grams per bodyweight kg) without there being an impact on your kidneys—IF you do not have impaired kidney function.
If you do have normal function, you can get away with eating an exceedingly high protein diet—in the short term. But the line between normal and impaired can be easily crossed if you’re not paying attention to your health. And because kidneys are silent killers, you may not know you’ve done any damage until it’s too late. So, at the very least, be mindful of what you eat and stay on top of your labs.
Now, for people with reduced function, it’s a different—and more complicated—story. Studies (on humans, FYI) do show that eating a high protein diet can have slightly accelerate function decline. So, if you have impaired function, it may be beneficial to eat a low to moderate protein diet. That being said, many of these studies have been conducted with sedentary or lightly active adults.
And that’s where it gets complicated. If you are a highly active, muscular person with one kidney, you will need to eat more protein. Still less than the average athlete (who can pack in more than 2.2 g/kg a day), but more than a non-active adult with kidney problems. Yet, because current recs for protein intake do not account for activity level, your doctor may likely apply a blanket rule to your nutrition and recommend an amount that is WAY too low for someone pushing weight.
This is where I say, push back. Show your doctor the research that proves highly active people need more protein, and that RDA guidelines need to be updated to reflect current science. Advocate for personalized guidance based on your labs and your health and not on what some outdated rule says. Work WITH them to find the best middle ground for YOUR health.
Q: Do you mess with diuretics or mess with your water at all if you’re in prep?
A: No. I may cut down some on how much water I drink (from a gallon a day to roughly 80 ounces), but I do not deplete myself or use diuretics. One of the worst things you could do for your kidney/s is not drink enough water—even for a short period.
Q: My doctor told me I should only do cardio because weightlifting will hurt my kidneys. Is that true?
A: NO. To be fair, pushing WAY too hard in the gym could lead to rhabdomyolysis—when you create more injury to the muscle than your body can adapt to. And that can lead to kidney failure—as well as multiple organ failure. It’s a risk all bodybuilders take. So, no, you do not need to stay away from lifting. But you do need to be very mindful of your training—that’s where a good coach comes in.
Q: Are there any exercises we’re not allowed to do?
A: I wouldn’t say there are any exercises we’re not allowed to do. But I would say we need to be careful about engaging in contact/blood sports (MMA, football, Muay Thai, etc). Direct impact to your remaining kidneys can cause irreparable damage. So, be smart and protect yourself.
Q: What about protein powders and protein supplements?
A: It depends on your health and your goals. Personally, I do not use protein powders because many of them have high sodium content, and I eat a low sodium diet. (I need to be cognizant of where I get my mg from.) So, I opt to get my protein from natural sources (yogurt, egg whites, chicken, cottage cheese), and I recommend my clients first do the same.