Try karnay main koi haraj nahi.
Yeh aik myth hay. Women folks use this hearsay to stop over consumption of Imlee/tamarind by boys.
Modern research did not yeild any usefull chemical and medicinal properties of tamarind. This can only be used as a mild laxative.
During my school days I used to steal imlee, ambia/unripe mango etc from school bags of my girl classmates and had consumed tons of sour stuff as a teenager. Girls in Pakistan used to consume lot of sour things and would bring some to to school too just because of this notion that consumption of sour things will enhance their breasts.
I heard this a lot from my classmates and others in those days that consumption of sour things by boys is not good and the will end up have girl like love handles. But I have normal manly love handles. I still like to consume a lot of achar and chutney.
I am hapily married I have three kids two of them are boys and I use this myth when I see my boys over consuming sour candy. This consumption of tons of sour stuff had no effect on my manhood or shape of the body.