Piling on the protein could potentially also lead to a second type of kidney stone, says Dr. Kroll. Calcium oxalate stones make up about 80% of all kidney stones. They’re not directly caused by protein, purines, or uric acid, but rather by low levels of calcium.

“Sometimes, when someone switches to a predominantly protein-based diet, they may develop a deficiency of calcium as a result,” Dr. Kroll says. “They may be isolating the protein from dairy products, as in the case of whey, which doesn’t contain a lot of calcium. So those people are at increased risk for calcium stones.”

“That’s something that can be really, really painful, but it’s not just going to be from protein alone,” says King. If you’re consuming a lot of protein, just make sure you’re not neglecting calcium-rich foods like dairy products and leafy greens. It’s also worth finding out if kidney stones run in your family, King says. “Family history roughly doubles the risk.”

Reeking havoc

Unlike gout or kidney stones, which can be offset to a degree by things like hydration and calcium, bad breath is often an unavoidable by-product of excessive protein consumption. “The issue of bad breath is real,” says King. “People often assume it’s a hydration issue, when it’s actually metabolic.”

In the body, protein is broken down into nitrogen, and then subsequently into ammonia. This happens regardless of how much protein you eat. “It’s the normal process of protein metabolism,” says King. “But if you’re consuming protein in excess, you’re going to be smelling that ammonia on the breath.”

Bad breath, or halitosis, can also result from when high protein intake is paired with an especially low-carb diet. “When high protein is combined with very low carbohydrates, the body also produces acetone as a result of ketosis, which can smell like nail polish remover,” says King. “Depending on whether someone is consuming an excessively high amount of protein or high protein and low carb, you can get two different halitosis outcomes.”

In either of these cases, where bad breath originates in the gut, mints and gum are like Band-Aids for a bullet wound.

How to make gains without goutmaxxing

You don’t need as much protein as you think. Step one is to be mindful of how much protein you’re actually consuming each day. That way, you can make sure you’re getting enough protein to fuel your goals without letting things get out of hand. “Most people don’t need anywhere near the amount of protein they’re being sold,” says King. “No more than 40% of your caloric intake should come from protein,” adds Dr. Kroll. “There’s really no reason for a person to pack in more than 200 grams of protein per day. It’s like taking in too many vitamins. It’s just going into the toilet.”

Add lowering your risk of gout and kidney stones to the long list of reasons to stay hydrated, too. “Whatever form of protein you choose, increasing your water intake will potentially lead to a reduction and better excretion of uric acid,” says Dr. Kroll. Making sure that you’re drinking enough water each day can also help mitigate the gut health impact of a high-protein diet. “Heavy protein intake without adequate fiber and water disrupts gut function quickly,” says King. “Digestive issues like constipation, bloating, and GI discomfort are among the most common downsides I see.”