The reason is that the heart has to work over-time pumping blood to dispel heat, and cool summer foods increase the burden on the spleen. Bitter and sweet things stimulate the heart and the spleen, so they should be shunned to avoid "adding oil to the flames." That means cutting back on desserts, in particular.
因為夏天氣溫高，心臟必須「加班」輸送血液以散熱、調節體溫；而生冷食物也會增加脾胃負擔，因此屬「同性」的苦、甜就應少食，以免「火上加油」，使心及脾胃太過「激動」，像巧克力就少碰為妙。