Could a high salt diet or high protein & fat (low carb) be to blame for my water retention?

Not entirely: The high salt would cause fluid retention in persons with heart or kidney disease. If healthy, you should not develop edema with this diet. It is important to note that high protein diet is not sure to be safe for kidneys for the long haul i. E. A year or more. If you have fluid retention, you need to have your kidneys and heart evaluated by your doctor.

Diet and water: Yes,high salt intake will promote fluid retention, particularly if your legs are in a dependent position most of the day and you are not exercising much; High protein and fat will not necessarily retain fluid, unless salt is a component. If you are dieting to lose weight, be sure to include exercise and be moderate with salt; put your legs up now and then.

Water retention: Almost certainly the high salt. I recommend the DASH Diet for low salt eatiing ISBN: 0-7434-1007-6 Kindle Book-13: 978-1-43914-059-8 OK with Dr and then start chap 9 exactly and your swelling will be gone in days if due to too much salt.