“Those that are trying to lose weight may want a higher protein intake to help with muscle retention,” he said. Physical activity also plays a huge role: If you’re lifting weights, that presents a need to increase your protein intake—same with cardio workouts, like treadmill training or a few rounds on your rowing machine.

There are diminishing returns when you consume too much protein, and he generally advises a maximum of 1.6 grams per kilogram of bodyweight. (Roughly five chicken thighs.) “Once you start getting above that level, the benefits are less certain,” he said.

Going past 2 grams of protein per kilogram of bodyweight, Mills said, also may contribute to increased fat stores, “because our bodies are not able to utilize a surplus amount of protein for fuel,” she said. Focusing too much on protein can also push other important things off our plate.

Since many protein sources are animal-based, they tend to be higher in fat than carbohydrate-containing foods, she added, which means upping protein can mean upping fat, “which can negatively affect cardiovascular health,” Mills said. And protein-at-all-costs can crowd out other valuable nutrients: “The more protein we consume, the less likely we are to consume a balanced amount of other food groups including carbohydrates, fruits, and vegetables, which are pertinent for energy, rich in fiber, vitamins, and help prevent against chronic diseases.”

While foods that contain all nine essential amino acids—also known as “complete proteins”—are typically consumed via meat, fish, dairy, and eggs, Mills noted that soy, quinoa, buckwheat, amaranth, chia seeds, hemp seeds, and nutritional yeast are all complete plant-based proteins.

And don’t let the name fool you. “Incomplete” proteins, like beans, peas, nuts, and vegetables, she said, “typically contain many of the vitamins and minerals our bodies require to function at an optimal level.”