A client who is taking an antibiotic develops diarrhea. As the client resumes a regular diet, the nurse offers yogurt and buttermilk, but also observes that the client has several small bruises. Which additional dietary change should the nurse offer?

The presence of multiple small bruises in a client who has been taking antibiotics and had diarrhea suggests vitamin K deficiency. The intestinal microbiome normally produces a significant portion of the body's vitamin K through bacterial synthesis. Broad-spectrum antibiotics disrupt this flora, and prolonged diarrhea further reduces absorption, both leading to reduced vitamin K availability. Vitamin K is essential for the synthesis of clotting factors II, VII, IX, and X; deficiency impairs coagulation and results in easy bruising and bleeding. Offering foods rich in vitamin K — such as dark leafy greens, broccoli, and cabbage — directly addresses this deficiency and supports clotting factor synthesis. Yogurt and buttermilk were already offered to replenish gut flora and address the diarrhea. Increased proteins rich in iron would address anemia from blood loss but not the underlying bruising mechanism. Potassium-rich fruits address electrolyte imbalances from diarrhea but do not resolve coagulopathy. Reduced cholesterol and fats is a long-term cardiovascular intervention with no relevance to bruising in this acute context. Vitamin K-rich foods are therefore the most appropriate additional dietary recommendation.