Yes, there’s a test that measures diamine oxidase (DAO) levels in the blood. No, it’s probably not worth your time or money to get it done. (Wondering what DAO is? Start reading here and follow the links at the bottom of that post for more information.)
There are two issues. The first is there’s no well-established range of DAO levels. There’s speculation and you’ll find ranges listed, but they aren’t yet backed by solid science. Also, it’s not known whether the amount of DAO in your blood is indicative of how much is in your gut, which is where it really matters.
Genetic testing can show if you have mutations in the genes related to DAO production, but not how much you actually produce. While the test confirmed that I probably make insufficient amounts of DAO, dietary research, an elimination diet and testing DAO supplements were more informative.
The best way to find out if you’re low in DAO is to try taking the supplement. You can get small a bottle of the highest strength DAO for about $30. If you’re going for a high dose, use Histamine Block rather than Histame. (The Amazon link defaults to the more expensive 60 capsule bottle. Click on “30 Easy-To-Swallow Vegetarian Capsules” in the box below the “in stock” notice to choose the less expensive bottle).
It took about a month of playing with the amount of DAO I took and how long before meals to take it before I hit on the right set up for me. The label recommends taking two no more than 15 minutes before every meal. I’ve found each capsule covers about 400 calories, though I take more if I’m eating a high-histamine food, like fish. I currently take it about 8 minutes before eating (or even drinking coffee or herbal tea) and am sure to finish eating within 45 minutes. As you’ve read, the change was drastic once I hit on the right combination.
This was while eating a low-histamine diet, which I recommend trying. Even if you don’t, read the list of high-histamine foods and take extra DAO when you eat them. (Some of those foods are also high in tyramine, which has long thought to be a migraine trigger. DAO does not help process tyramine and there is no digestive enzyme that claims to.)
The capsules are expensive (about $1 each), so I initially felt a lot of pressure to take no more than I absolutely needed. For the sake of dietary variety, I’ve relaxed a bit and now err on the side of too much with foods I’m uncertain about. Other than pocketbook pain, I have no noticeable side effects. I thought heartburn was an issue for a while, but that has resolved (it was likely due to reintroducing fat after going so many months on a very low fat diet). I’ve been reassured that DAO is safe and that any that’s unused gets flushed right out. That’s why you have to take it before every time you eat — it doesn’t stick around.
I know many of you are hoping that DAO will help you as much as it has me. If you do decide to try it, play around with dosing and when you take it. If you get any relief from it, it might be another addition to your treatment plan. Every little bit adds up.
Still have questions? Please ask them in the comments or email me at kerrie[at]thedailyheadache[dot]com and I’ll try to answer them.