Eating too much protein will make your bones brittle
This statement is unfortunately plastered inside of nutrition textbooks. The first problem here is that “too much” is rather vague. Someone might hear this, think they are eating too much protein, and then cut out all protein at breakfast and lunch—bad idea! The other issue here is that the relationship between protein and your bones is complicated, as you also need to consider how much calcium you’re eating.
In order for your protein consumption to potentially have a negative impact on your skeleton, you’d need to be eating 2.5 times the recommended daily allowance for protein (that’s 171 to 190 grams if you’re following a 1,800- to 2,000-calories diet) and taking in less than 60 percent of your recommended calcium. As the chances of both of these are very slim, this “advice” is more a nutritional scare tactic used to get people to eat less protein and more carbs than anything else.