Q. A few years ago I read that selenium was good for everyone and that Brazil nuts were high in selenium. Since I love Brazil nuts, I bought them regularly and ate about three a day. After a few months I began suffering severe leg cramps that woke me from a sound sleep every night. They lasted from ten to fifteen minutes with sharp pain no matter what I tried.
I had no idea what was causing them, so I decided to eliminate foods one by one from my regular diet. When I eliminated Brazil nuts, the cramps didn't occur. I experimented with them several times. Whenever I eliminated them, the leg cramps went away and when I ate even one, the cramps returned.
I'm not allergic to other kinds of nuts. Walnuts, pecans, almonds and cashews don't bother me. Is this reaction commonly known or just peculiar to me?
A. We have not heard of muscle cramps as a reaction to Brazil nuts. At first, we suspected that your regular Brazil nut consumption might have resulted in selenium toxicity. A half-dozen nuts have more than 500 micrograms of this mineral, above the tolerable daily limit of approximately 400 micrograms.
Symptoms of selenium overdose include hair loss, brittle nails, fatigue, rash, digestive upset, irritability and garlic odor on the breath. Since muscle cramps have not been previously reported as symptoms of excess selenium, we imagine this reaction is particular to you.