If you are self employed and the health insurance policy meets the following IRS requirements, you can deduct the premiums on Schedule C.
IRS requirements are:
1. The insurance plan must be established in your name or under your business name. It cannot be part of a group policy from another employer.
2. You cannot take the deduction for any month you were eligible to participate in any employer (including your spouse's) subsidized health plan at any time during that month, even if you did not actually participate.
See https://www.irs.gov/publications/p535/ch06.html#en_US_2015_publink1000208843 for more information.