The quotation presents moderation as preferable to excess. By suggesting that people are less likely to regret eating too little than eating too much, Jefferson uses appetite as a practical example of self-restraint. The underlying idea is that avoiding excess can reduce the likelihood of later discomfort or regret, while encouraging deliberate control over immediate desires.

In Jefferson’s letter to Thomas Jefferson Smith, the saying appears among a broader set of practical rules for personal conduct. Its emphasis is therefore on character and discipline rather than on nutrition or medical guidance. Read in that context, the maxim promotes temperance: the habit of stopping short of excess and exercising judgement over appetite. More broadly, it reflects the letter’s recurring concern with moderation, prudence and the management of everyday impulses.