Heterobasidiomycetes, including the jelly, rust and smut fungi; Previously the entire Basidiomycota were called Basidiomycetes, an invalid class level name coined in 1959 as a counterpart to the Ascomycetes, when neither of these taxa were recognized as divisions.
Too much of anything is bad is general rule of thumb. I found several articles which favour eating peppermint and detail side effects of over consumption. But in general there are some side effects of eating altoids and other mint gums. Mouth sores, headaches, stomach burns are few of them. Check out following links for more information. peppermint: Uses, Side Effects, Interactions and Warnings.
There are two great, natural treatments for anxiety-related stomach issues: Lemon balm has been used since the Middle Ages as a calming herb. Take 400 mgs twice daily to prevent your stomach from reacting to your worried thoughts, available in drugstores for about $4. You can also try iberogast, available in health food stores for around $20. Iberogast is a blend of plants and herbs, including caraway, chamomile, licorice, milk thistle and peppermint. Adding 20 drops to your water can sooth the receptors in your stomach when anxiety hits. Take an Integrative Approach to Worry: Focus on the Mind-Body Connection