Watercress, also known as watercress, is sweet and bitter in taste and cold in nature. Has the effects of clearing away dryness, moistening lung, resolving phlegm, relieving cough and inducing diuresis. It is a kind of health-care vegetable for benefiting the brain and keeping fit. Beef has the effects of invigorating the middle energizer, invigorating the spleen and stomach, strengthening bones and muscles, resolving phlegm and calming wind, and quenching thirst. Suitable for people with stagnation of qi, shortness of breath, weakness of muscles and bones, anemia and yellow complexion. So the two do not conflict and can be eaten together.

It is ok for diabetics to eat beef, because beef is mostly lean meat. There is "watercress lean broth" in the diabetic diet, which of course refers to watercress plus lean meat. But I think this kind of lean pork can be replaced by beef. People with diabetes should avoid eating greasy things, so beef is more suitable. Regarding the dietotherapy and treatment of diabetes, you should ask your attending doctor first, only he knows the patient's situation best.