Can eating magnesium-rich foods make you sleepy?

People often report that magnesium supplements in the 200-400 mg range make them relaxed/sleepy and actually will target their supplementation around bedtime for this reason.

Does eating foods rich in magnesium have the same effect? I ask because nearly every day around lunch I will have a cavalcade of vegetables which usually includes 12 oz of spinach, 12 oz of cauliflower, and 12-16 oz of broccoli (or some variation of the three).

I’m wondering if all the magnesium (especially in the spinach) could be contributing to my afternoon slump/nap.