It's easy to get answers about health and nutrition! Just send your question by email to [email protected] and Dr. Harlan will respond to selected questions of general interest. Answers will be posted in the Ask Dr. Gourmet newsletter (sign up now!) and archived in the Ask Dr. Gourmet section of the website.
I understand that vinegar may help lower blood sugar levels. Will lemon juice be just as helpful?
I love this sort of question because it lets me discuss how science works.
I have been skeptical about patients who come in and tell me that they are taking vinegar for their health. This is usually apple cider vinegar and it just seemed silly to me but I have also felt that this is like so many supplements - probably not harmful, but probably not helpful either.
However, it appears that this "silly" idea may have some merit. As I reported in a Health & Nutrition Bite back in 2009, vinegar might be helpful for controlling blood sugar. A small study but encouraging.
It seems a simple leap to say that it might be the acidic nature that is helping, and that lemon juice might be just as helpful, but we don't really know why the vinegar works. I have searched the literature and did not find a study that looked at this. We could reason that since vinegar helps control blood sugar, and both vinegar and lemon juice are acidic, so lemon juice also helps control blood sugar. Unfortunately, science doesn't work this way. Just because A = B and B = C, one can't make the leap that A = C.
That said, lemon juice is really good for you. Two tablespoons contains about 15 mg of Vitamin C (25% of the RDA). I love the bright fresh taste and lemon juice adds so much flavor without adding calories. So while it may not help control blood sugar in the same way as vinegar, it can help by adding bright, low calorie, high vitamin flavor.
Thanks for writing,
Timothy S. Harlan, MD, FACP