Guar gum needs to be thin enough to make it easier to pump. Then as it flows down the pipe, the fluid needs to gel up to support the proppant and flush it deep into the fractures. After that process, the gel has to break down so we can flow back and recover the fracking fluid, but leave the proppant behind. This requires a chemical process which produces then breaks the gel cross-linking at a predictable rate. Guar+boron+proprietary chemicals can accomplish both of these goals at once. Guar gum retards ice crystal growth nonspecifically by slowing mass transfer across the solid/liquid interface.
Guar gum or nutritional supplements containing them are consumed concomitantly with it, but this is less of a concern with guar gum than with various insoluble dietary fibers. Some studies have found guar gum to improve dietary glucose tolerance. Research has revealed the water-soluble fiber in it may help people with diabetes by slowing the absorption of sugars by the small intestine. Although the rate of absorption is reduced, the amount of sugar absorbed is the same overall. This may help diabetic patients by moderating glucose "spikes". Guar-based compounds, such as hydroxypropyl guar, have been in artificial tears to treat dry eye.