Can diet help?
Research does not suggest that diet can cure or prevent Hashimoto's disease.

However, one autoimmune disease will often occur alongside another. Studies suggest that some people may have hypothyroidism with low-level celiac disease. This implies that avoiding gluten may benefit some patient with hypothyroidism that stems from an autoimmune condition.

In another study of 83 patients, 75.9 percent were found to be lactose intolerant. After following a lactose-restricted diet for 8 weeks, participants experienced a significant decrease in blood levels of TSH.

Any changes to diet or use of a supplement, must, however, be discussed first with a physician.

From: Medical New Today, !/2/2018
Hashimoto's Thyroiditis: What You Need to Know
the whole issue is about thyroid
link: https://www.medicalnewstoday.com/articles/163729.php