Recent studies suggest that an intake of vitamin E in excess of that found naturally in a balanced diet may actually increase the risk of developing certain illnesses
A.
B. Recent studies suggest that taking vitamin E in excess of that found naturally in a balanced diet actually increases the risk of developing certain illnesses
C. Certain illnesses may be at a higher risk of development if vitamin E is taken in excess of a balanced diet, according to recent studies
D. According to recent studies, the intake of vitamin E, if in excess of that found naturally in a balanced diet, may actually increase developing certain illnesses
E. Vitamin E, recent studies suggest, if in excess of that found naturally in a balanced diet, may actually increase the development risk of certain illnesses
The correct answer is A. My question is, doesn't "that" lack an appropriate antecedent? If "that" = "[an] intake", the phrase would be "in excess of an intake found naturally in balanced diet...". It doesn't seem to me that an intake can be FOUND in a balanced diet.
Any thoughts?