I take levothyroxine (T4) and metformin. Can I take NAD+ and resveratrol?

Hello, Miguel: In general terms, there are no known significant interactions between levothyroxine, metformin, NAD+ or resveratrol. However, this does not mean that these supplements are suitable for everyone. Levothyroxine should always be taken on an empty stomach, with water only, and it is advisable to wait at least 30-60 minutes before eating breakfast or taking any other medication or supplement so as not to reduce its absorption. As for NAD+ and resveratrol, although there is growing interest in their possible role in healthy ageing and cellular metabolism, the scientific evidence in humans is still limited and does not justify their universal use. If you decide to use them, my recommendation is to do so under medical supervision, especially if you have other conditions or take more medication. In addition, if you are on levothyroxine, it is advisable to have periodic thyroid function checks to confirm that the treatment remains effective. I hope this resolves your question. Kind regards.