Passage Summary: Type B lipid profiles are riskier for heart disease than Type A. In a study, a low-fat diet helped Type B people lower their cholesterol but didn't change their profile. However, 40 percent of Type A people on the same diet actually switched to the riskier Type B profile.

Reasoning: N/A

Analysis: We must treat these experimental results as absolute facts. The most striking data point is that a significant portion of the 'low-risk' group (Type A) moved into the 'high-risk' group (Type B) after starting the diet. This suggests that for some individuals, a low-fat diet might actually increase the risk of heart disease by triggering a shift in lipid profiles. Look for an answer that synthesizes these facts without going beyond the data provided, specifically focusing on the unintended negative consequences for the Type A group.