How late is "too late" to take protein at night?

That’s 2 well controlled studies in favor of eating much of your daily protein intake later in the day. However, these studies cannot tell us if it was the energy or just the protein timing that caused the positive effects.

Enter Jordan et al. (2010). These white-coat-wearing amigos compared two groups receiving a carbohydrate and a protein beverage at breakfast and about 10 hours after waking up and they measured nitrogen balance, a measure of daily protein balance and lean tissue growth. One group received the carbs at breakfast and the protein later in the day and the other group received the carbs later in the day and the protein at breakfast. The group receiving the protein later in the day had a significantly more positive nitrogen balance than the group receiving the protein at breakfast. Because the study authors controlled for carb and therefore energy timing, only the protein timing could have caused this difference. The most remarkable thing about this study is that the protein beverage only contained 15 grams of protein in a diet containing more than sufficient protein and still they found a significant effect.

Conclusion

Energy intake and macros are far from all that matters in a diet and can’t be considered strictly more important than nutrient timing. CRPT, the timing of your protein intake over the day, can aid both muscle gains during a bulk and muscle retention during a cut. It’s so important that it can make the difference between significant hypertrophy and complete stagnation. There is still much that needs clarification by future research, but all current evidence points in the direction that you should consume a significant amount of your daily protein intake later in the day. Whether energy timing also has an effect and what the optimal timing is remain uncertain at this point.

Let CRPT serve as an illustration that, even in a time where the strength community is getting back to basics, sometimes it’s the little things that make all the difference.

Take home message: Consume at least a single meal with a good portion of protein in the hours before going to sleep.

It depends on what time you fall asleep. Drinking a protein shake while sleeping could pose a potential choking hazard so I would recommend drinking it before sleeping. I would allow enough time between drinking a protein shake and sleeping that you're able to brush your teeth. Other than that, as late as you'd like.