There is no love sincerer than the love of food.

The saying contrasts romantic or moralized notions of love with the straightforward, dependable pull of appetite. “Love of food” is presented as “sincerer” because it is immediate, embodied, and largely free of self-deception: people may rationalize, perform, or idealize other kinds of love, but hunger and pleasure in eating are difficult to counterfeit. The humor lies in deflating lofty sentiment with something ordinary, while also hinting at a serious point: human motives are often grounded in material needs and pleasures. Read this way, the line satirizes social affectation and reminds us that the most reliable affections may be the simplest ones.