As Helen Rosner wrote in the New Yorker (Feb 27,2020), “Yuzu is yuzu; there’s nothing else quite like it.” Yuzu has already become a popular international citrus fruit. If you have never experienced Yuzu, you are in for a treat. But could there be any health problems with Yuzu?
We know that grapefruit juice can dangerously raise blood levels of several drugs (statins, calcium channel blockers) because it inhibits enzymes that normally break down the drugs. There is also evidence that the same happens with the body's estrogen hormones, potentially increasing estrogen levels and the risk of breast cancer in women and erectile dysfunction in men. Could Yuzu do the same?
Yuzu is new to the West, and it takes up to ten years for a yuzu tree to fruit, but Yuzu juice is likely to be on grocery store shelves soon, the way lemon and lime juice are today.
Research to date points out some probable anti-oxidant, anti-inflammatory and cardioprotective properties similar to other citrus. In one study (2015 Japan) Yuzu inhibited platelet aggregation to a degree that would add to the effects of aspirin and other anti-platelet drugs.
The question of whether Yuzu contains the chemicals found in grapefruit (called furanocoumarins) that inhibit drug and hormone metabolism has not been fully answered. Japanese researchers showed in 2018 that lime pulp and zest contained the highest concentration of these substances, higher even than grapefruit, and another Japan study (2011) showed that Yuzu had very low activity of the same substances.
So, at the present time, Yuzu appears not to have the same risk as grapefruit or lime, but juice from Yuzu can inhibit platelets, which would account for some cardioprotective properties but also the potential for additive effect in those taking anti-platelet drugs.
