I used to have issues with edema. In my case, it was down to an inherited vascular insufficiency (think varicose veins), complicated by obesity and blood pressure issues.
The cure for me was a plant based diet that also avoids most processed foods and added oils. Obviously that helped with the blood pressure and (to an extent) the obesity. But the edema went away in a matter of just a few days.
As I understand the reason (and this is controversial -- lots of people disagree) too much dietary fat is detrimental to the texture of the cells that line your blood vessels. In extreme cases this used to be called "hardening of the arteries", especially when combined with vascular plaques which may or may not have to do with cholesterol consumption (although they are, literally, made of cholesterol). A plant based diet with less than 10% of its calories from fat (which is most of why it has to be plant based, as even the leanest animal foods tend to have more fat than this) has the effect of dilating your blood vessels and making the epithelial linings thereof more elastic and flexible. (In my case this has gotten so extreme that the phlebotomy nurse at my clinic struggles to take blood samples -- my blood vessels bounce and roll when she pokes them with the needle, making it hard for her to get a needle in one.)
I also vote for following Dr. Esselstyn's and Dr. Mcdougall's advice. I've been on their forums for years (and am mostly compliant to their diets) and have seen miraculous posts of health benefits from simple changes, re: heart issues/ edema. Best of luck to OP and I hope you find some relief from your problems.
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