For the last week I've been eating lamb bone broth every day, but every time I eat it I feel really tired and need to take a nap. Luckily my office is at home so I can catch 40 winks but still... Last time I was napping was back when I was getting white bread energy crashes.

I'm actually sleeping pretty well and eating plenty of nutritious food (carbs, fat and protein). Any ideas why bone broth might be making me tired?