Q: I have heard about taking nine raisins soaked in gin for osteoarthritis. Now I read that eating raisins will help reduce bathroom trips at night.

Can it be the same raisins? Then I can do it all at once.

A: We have not been able to find any research on either use for raisins, although some laboratory and animal studies show that grape-derived compounds can reduce inflammation (Journal of Medicinal Food, April 2014; Phytomedicine, Feb. 15, 2014).

You could try eating some raisins before you brush your teeth at bedtime to see if that reduces nighttime bathroom trips. That will also allow you to gauge whether you are getting any benefit against joint pain.

Q: I am interested in using cherries or cherry juice for blood pressure control, but I have a few questions about dosing. There are three different vendors of concentrated tart cherry juice at my local store. Each advises a different dosing of juice, from 2 tablespoons to 8 ounces of concentrated juice. (All advise mixing with something.) This is a large difference in dose.

What is the actual dose recommended? Is one dose in the morning enough, or should I be taking it twice a day?

I’d like to take dried tart cherries in my morning oatmeal (rather than juice) but I can’t find anything about an appropriate dose. For years, I’ve been adding a few dried cranberries to my oatmeal each morning to make it less boring. Do dried cranberries contain the same active ingredient as dried cherries? If so, what would be the effective dose of cranberries? My BP increases yearly, so I must not be taking enough.

A: Both tart cherries and cranberries appear to inhibit angiotensin converting enzyme (ACE). This means they work on the same pathway as several popular blood pressure pills, such as lisinopril.

Trying to determine the most effective dose of dried fruit or juice is challenging. One randomized controlled trial found that 480 milliliters (about 2 cups) of tart cherry juice daily lowered systolic blood pressure and LDL cholesterol (Food & Function, June 20, 2018). The only way to tell if such approaches are helpful for you would be to monitor your BP periodically throughout the day.

If you are interested in other natural approaches to controlling hypertension, you could consult our eGuide to Blood Pressure Solutions. It is available in the Health eGuides section at www.PeoplesPharmacy.com.

Q: Mosquitos love me. I used to go to a lake in Ontario for a couple of weeks each summer. The fishing was awesome, but the mosquitos were big and plentiful, and would bite me, leaving lots of raised welts that itched like crazy.

Then my aunt (an operating room nurse) told all of us to start taking vitamin B1 (100 mg once a day) for two weeks before we leave for Canada. It worked like a charm. Mosquitos would descend upon our boat and land on my bare skin and then take off without biting! I was able to enjoy fishing without being bitten once. I swear by the vitamin B1.

A: Vitamin B1 (thiamine) has been controversial as a mosquito repellent. Many people, like you, report benefit from oral doses. However, a study found no effectiveness (Journal of the American Mosquito Control Association, June 2005).

On the other hand, a tiny pilot study recently demonstrated that thiamine hydrochloride (vitamin B1) can be effective as a topical mosquito repellent (Biological and Pharmaceutical Bulletin, February 2020).