Alopecia is an autoimmune disease. Studies show it is genetic. It has to be treated with immunosuppressant topical cream daily like Elidel. Plaquenil is an oral immunosuppressant. Plaquenil requires a baseline eye test before you start it. Scarring Alopecia & frontal fibrosing alopecia are not cured with diet. Having a good diet is generally good for everyone and a low inflammation diet of course is best. It does not cure alopecia. Alopecia like other autoimmune conditions flares up. During the flare apply steroids topically to calm the redness because if you don't those follicles are permanently lost. This is something that you have to keep up with if you want to slow down the progression. FFA can recede up to 6 in. Heat and sweat tend to exacerbate flares. No environmental factors have been shown to trigger the onset of FFA. Birth control, aspartame, sunscreen titanium oxide, and hepatitis B vaccines have been considered without conclusive results. FFA is often accompanied by one or two other autoimmune conditions as time goes on. Like rosacea, Hashimoto's, lupus, eczema, Meniere's disease, rheumatoid arthritis, Crohn's disease, sojourns, and there are many more. Adjunct treatment for hair regrowth is debatable. Minoxidil and Rogaine are often prescribed but they speed up the cycle of of hair falling out and regrowing and with FFA that hair may not regrow. My personal preference for stimulating new growth is a mixture of rosemary oil and rosehip seed oil 50/50. Apply at night it's a thin oil, gently massage into the scalp. You can Google the benefits of both oils. Neither minoxidil or rosemary oil are recommended as the only treatment for FFA, this is an adjunct treatment to immunosuppressants and intermittent application of steroids.

Genome-wide association study in frontal fibrosing alopecia identifies four susceptibility loci including HLA-B*07:02 | Nature Communications https://www.nature.com/articles/s41467-019-09117-w