Hello and welcome to our family. If, by plant based diet, your doctor is suggesting that you avoid too much red meat (or four-legged animals), then I agree with that. Many of us have had to restrict our intake of protein rich foods, such as red meats. I try to eat strictly fish and fowl.
It is suggested that the best diet is the one recommended by the Heart Association. We are also told to avoid legumes, alfalfa sprouts, and many herbal medications. There is a sticky here that discusses diet options.
However, if your doctor is suggesting a holistic approach to treating your Lupus, then I would suggest that you find another doctor. As Tgal mentioned, there are no holistic treatments that are proven to lessen symptoms, cause remission, or cure Lupus. There is no cure for this disease and only proven medical treatments can lessen symptoms if taken with the appropriate lifestyle changes.
We are here to help you as much as we can. I wish you the very best!
Peace and Blessings
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