Couple of things come to mind.
1. This is a really busy time on the editorial page with so many bills before Congress and statehouses. If there's a way to tie the piece to something new happening right now, that could help. Perhaps the latest study or court case or FDA regulation. Best to lead with the newest info rather than the oldest.
2. You could also remove the proper names Nutrasweet, etc. and replace them with general verbiage -- non-plant-derived sweeteners found on grocery store shelves and restaurant tables.
3. If there are more recent studies to cite throughout, that will make your letter look more timely.
Hope something here help. And good luck.
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