The basis for the predominant theory as to why rice and other grains, such as wheat, have played a prominent role in marriage ceremonies for centuries, is that they are fraught with symbolism of fertility and of prosperity. By throwing rice at the bride and groom at a wedding, guests symbolically wish them a lifetime full of these blessings.

Historically, in certain primitive tribal cultures, the mere act of supping on rice together bound a couple in matrimony, as eating this local food together implied their living together. In other cultures, the symbolic eating of rice together preceded a shower of rice over the married couple.

Perhaps the most curious use of rice in the wedding ceremony, was its use in some cultures not to unite the happy couple, but to feed the uninvited evil spirits who always attended the ceremony. The rationale behind this practice was to ward off evil, as well-fed evil spirits would bring no harm to the blissful couple.

In early Roman times, wheat was the grain of choice for the wedding ceremony, as wheat, not rice, symbolized fertility. The virginal bride carried a sheaf of wheat in her hand throughout the ceremony, or wore a garland of wheat in her hair. Instead of the bride tossing a bouquet, as is traditionally done today, wedding guests tossed grains of wheat at her, and young, single girls clambered for the grains that bounced off of the young bride, believing that these grains could ensure them a trip down the bridal path soon thereafter.

The wheat tossing custom fell by the wayside under the reign of Queen Elizabeth I of England, when the once airborne wheat instead was baked into small cakes, which the guests then crumbled and tossed over the bride's head. Even this tradition gave way to another, in which a large wheat cake was baked, then eaten, not tossed. Wedding guests, literally left empty-handed, had no recourse but to find a suitable substitute for the costly wheat cakes. They needed something to toss at the bride to reinstate themselves as active participants in the ceremony. The natural choice was none other than cheap, clean, white rice, and the tradition then born has stuck to this day.