Upper Intermediate Stories
The resin is collected from trees the way rubber is collected. Today manufacturers include sweeteners like cane or beet sugar or synthetic sweetener like aspartame. They also include glycerin vegetable oils as softeners.
The changing climate is making trees with the resins increasingly scarce so companies looking to synthetic substitutes.
Most commercial gums can swallowed without causing harm. They are not broken down by the digestive system simply pass along it.
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