HK1 and hydrops fetalis: To investigate how diets impact on immunometabolism, enzymes and markers involved in critical metabolic pathways were analyzed using MetFlow, a flow cytometry‐based method achieving single cell‐level metabolic profiling with comparable robust performances to conventional approach like Seahorse experiments.[17] Hexokinase 1 (HK1) was validated as a readout of glycolysis,[17] a critical mediator of inflammatory responses, specifically those driven by T cells.[17, 18, 19, 20] In dLNs, HK1 was upregulated in HC‐derived T cells, as well as in cDCs, compared to HF (Figure 3E).