How is this a fact. It seems science writers have difficulty distinguishing between facts and evidence. It may be proper to say that based on the evidence and the current knowledge of the causes of cavities that it is probable that he had a high carb diet.
I'm not a dental expert but I know there are numerous factors including hereditary, fluoride in water and personal hygiene. How its possible for them to isolate these factors when they have only one subject leads me to believe that the statement only rises to the level of speculation and not even hypothetical and clearly not fact.
Or he may not have had ‘Dental’ as part of his employer’s healthcare plan.................